Nitrogen affects and genotypic variation in Cd absorption, translocation and chemical forms in wheat

Nitrogen affects and genotypic variation in Cd absorption, translocation and chemical forms in wheat | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Nitrogen affects and genotypic variation in Cd absorption, translocation and chemical forms in wheat Xiaoli Wu, Miao Liu, Ming Li, Shizhao Li, Tao Xiong, Chaosu Li, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5404240/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 6 You are reading this latest preprint version Abstract Reasonable nitrogen (N) and low grain cadmium (Cd) accumulators can effectively reduce grain Cd content in wheat; however, the underlying mechanism remains unclear. This study aimed to investigate N affects and genotypic variation in Cd absorption, translocation and chemical forms in low (Chuannong30) and high (Chuanmai88) grain-Cd-accumulating wheat. Pot experiment was arranged in a completely randomized design consisting of two-factors: two Cd levels (low, 0.5 mg∙kg -1 ; high, 1.5 mg∙kg -1 ) and six N treatments (0, 45, 90, 135, 180, 225 kg∙ha -1 ). The results showed that both cultivars can be grown in low-Cd soil under N fertilization rate of 180 kg∙ha -1 , without Cd toxicity issues; the low grain-Cd accumulating cultivars can be grown in high-Cd soil under fertilization rates < 135 kg∙ha -1 , without grain toxicity. Increasing N fertilization improved Cd absorption, translocation and distribution in both cultivars, with a higher effect observed in Chuanmai88, the lower grain Cd concentrations of Chuannong30 may be attributed to low root absorption and low Cd translocation from leaf to grain. N fertilization increased all Cd chemical forms (except residual-Cd) in the root and leaf in both cultivars, especially under high soil Cd condition, Cd fractions extracted by 80% ethanol were predominant in root and leaf of both cultivars and the concentrations and proportions were also higher in Chuanmai88 than in Chuannong30. Moreover, increasing N fertilization significantly decreased soil pH, increased soil Cd exchange capacity and soil Cd bioavailability, resulting in increased Cd accumulation in plants, Chuanmai88 promoted the activation of the Cd migration in the soil. cadmium food safety grain heavy metals nitrogen wheat Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Introduction Cadmium (Cd) is a serious toxic, non-essential element which is affecting approximately 7.75% of farmlands in China (Chen et al. 2024 ;). It is readily absorbed by crops and enters the food chain, and poses a severely threat to food safety (Zhang et al. 2024 ; EI Rasafi et al. 2022 ; Ali and Khan 2018 ). Wheat, as a one of most important crops worldwide, have been confirmed to have higher Cd accumulate ability than other corps, mainly via the roots transport to the aboveground parts where it accumulates in the grain, wheat grain-derived products are also a prime source of Cd in humans (Chen et al. 2023 ; Shi et al. 2020 ; FAO 2019; Rizwan et al. 2016 ). Consequently, it is of great significance to reduce the Cd absorption, translocation in wheat for ensuring human health. Importantly, Cd accumulation and absorption in wheat grains is affected by many factors, such as soil condition, atmospheric deposition, wheat cultivars and management practices (Liu et al. 2023 ; Ma et al. 2022 ; Liu et al. 2020 ). N fertilizers play a crucial role in crop growth and grain yield (Yang et al. 2020 ; Srivastava et al. 2019 ), N rate is closely related to Cd absorption and tolerance (Ye et al. 2022 ). Reasonable N fertilization management is a time-saving, environmental-friendly, cost-effective, and promising strategy to inhibit Cd absorption and alleviate Cd toxicity in wheat (Chen et al. 2024 ; Zhu et al. 2023 ; Khatun et al. 2022 ; Cheng et al. 2021 ; Yang et al. 2020 ), however, N fertilizer is often used in excess to increase yield, although this practice usually results in the production of Cd-contaminated crop in unpolluted soil (Yang et al. 2020 ). Lots of studies have exhibited the effect of N fertilizers on Cd uptake in wheat; great majority found a significantly positive relationship between grain Cd concentration and N fertilizer rate, the addition of various types of N fertilizers, for example calcium nitrate, urea, ammonium nitrate and ammonium-nitrogen, could prominently increase wheat grain Cd concentration (Cheng et al. 2021 ; Ata-UI-Karim et al. 2020 ; Svecnjak et al. 2013 ; Li et al. 2011 ; Perilli et al. 2010 ). Li et al. ( 2011 ) showed an increase in Cd concentration in wheat grains with increasing N rates, regardless of Cd concentration in both soil and grains. Increasing N rate enhances Cd accumulation and translocation from roots to aboveground parts and promotes Cd accumulation in grain (Larsson and Asp 2011 ). Furthermore, N fertilizer changes the Cd bio-available in soil and accumulation in wheat (Rizwan et al. 2016 ; Ishikawa et al. 2015 ; Li et al. 2013 ). Therefore, optimal N fertilization is vital to manage Cd bioavailability and accumulation in crops. Genotypic variations have been reported in Cd absorption, transportation, and accumulation abilities in wheat (Chiao et al. 2020 ; Yang et al. 2022 ). Low Cd accumulation cultivars of wheat can effectively decrease grain Cd content, which is a useful way to reduce the risk of people consumption (Yang et al. 2022 ). However, related mechanisms of Cd absorption in the wheat grains between cultivars still unclear (Xiao et al. 2020 ; Wang et al. 2024 ). Low Cd accumulation cultivars is related to heritable properties, such as reduced expression of transport proteins (Zhang et al. 2020 ; Lin et al. 2022a , b ), small root morphological (Liang et al., 2017 ), and less biomass (Liu et al. 2020 ). Kubo et al. ( 2016 ) exhibited that wheat have various mechanisms to inhibit Cd transportation to grains, and those mechanisms could be independent from biomass partitioning. Additionally, several researchers believed that chemical forms of Cd are closely associated with its accumulation absorption. Xiao et al. ( 2020 ) observed that the proportion of Cd in shoot soluble fraction in high Cd accumulation cultivars were prominently higher than these in low Cd accumulation cultivars. Rhizosphere bacteria influence soil Cd bioavailability and occupy the important position in plant response to Cd stress (Lopes et al. 2016 ). Overall, it is valuable to understand the mechanism of different Cd accumulation cultivars in response to varying soil N and Cd levels. Therefore, this study aimed to investigate the effect of N application rates on the growth, Cd uptake, translocation, and chemical forms in different Cd accumulation wheat cultivars under different Cd levels, and identify the best nitrogen application method for different cultivars. Materials and methods Study site and experimental materials Soil was sampled from the 0-20cm layer of a paddy rice field located in Guanghan City (31°69′N, 104°41′W; altitude 450 m), Sichuan Province, southwest China in July 2021. After soil air-drying and sieving through a 2-mm sieve, physical and chemical properties were measured. The soil properties were as follows: pH, 7.62; soil organic matter (SOM), 28.80 g∙kg − 1 ; cation exchange capacity (CEC), 7.12 mol∙kg − 1 ; total nitrogen (TN), 1.61 g∙kg − 1 ; total phosphorus (TP), 1.54 g∙kg − 1 ; total potassium (TK), 1.19 g∙kg − 1 ; total Cd, 0.501 mg∙kg − 1 ; available phosphorus (AP), 7.25 mg∙kg − 1 ; and available K (AK), 103.60 mg∙kg − 1 . Two cultivars with vary Cd uptake, Chuanmai88 and Chuannong30, were selected from 84 wheat cultivars conducted in our previous study (unpublished). Notably, the Cd concentration in Chuanmai88 grains (0.238 mg∙kg − 1 , DW) was 4.175-fold higher than that in Chuannong30 grains (0.057 mg∙kg − 1 , DW) when grown in Cd-contaminated soils. Therefore, Chuanmai88 and Chuannong30 were considered as Cd high and low Cd accumulation cultivars, respectively. Experiment design Pot trial was conducted under open-air conditions during two consecutive seasons (2021/2022 and 2022/2023). It was arranged in a completely randomized design consisting of two-factors: two Cd levels (0.5 and 1.5 mg∙kg − 1 soil as cadmium sulfate) and six N levels (0, 45, 90, 135,180, and 225 kg∙ha − 1 pure N as urea, as the basic fertilizer). Wheat seeds without disease and insects were selected and surface-sterilized into 10% H 2 O 2 (w/w) for 12 min, rinsed, then soaked in distilled water overnight, and germinated under room temperatures for 24 h. Pots were filled with 7 kg soil and 18 wheat seeds were sown per plastic pot. Each cultivar was replicated 10 times, making a total of 240 pots. After growing for 2.5 weeks, nine uniform seedlings were retained per pot. Basal fertilizers were added as phosphorus oxide (90 kg∙ha − 1 ) and potassium chloride (90 kg∙ha − 1 ) into soil. All pots were rearranged monthly. Soil sampling and physicochemical properties analysis At maturity, five pots of soil were sampled from the surface (0–20 cm). soil samples were passed through 0.15, 0.25-, and 2.0-mm sieves and stored in glass containers for physicochemical analysis after air-drying and manual grinding. Soil pH measurement refer to method of Khaliq et al. ( 2019 ). SOM were measured using potassium dichromate volumetric method (GB 9834–1988) and CEC were determined using hexamminecobalt trichloride solution (HJ 889–2017). Total Cd concentration was measured using inductively coupled plasma mass spectrometry (ICP-MS, Thermo Fisher Scientific iCAP RQ, USA). Available Cd concentrations were extracted with DTPA extracting solution under constant shaking for 2 h at a soil: water ratio of 1:20 (w/v). Cd fractions in the soil, including exchangeable Cd, carbonate–Cd, Fe–Mn pesticides–Cd, organic matter–Cd, and residual Cd, were refer to method of Li et al. ( 2022 ). Plant sampling and Cd concentration analysis At maturity, three pots were selected per treatment for plant sampling. Plants were extracted from the soil by manual and divided into the root, stem + sheath (stem), leaf, grain, rachis + husk (husk). All plant samples were stored at 105 °C for 25 min and dried at 70 °C to a constant weight for dry matter, then, the samples were ground, passed through a 0.15-mm sieve and stored in a plastic bag to measure for Cd concentration. For chemical forms of Cd in plant determination, plants were harvested from two pots per treatment at anthesis. Roots and leaves were washed using deionized water, followed by the immediate freezing of fresh plant samples in liquid N 2 for analysis. Chemical forms of Cd in roots and leaves were extracted stepwise with five extracts and in residues, according to the described by Xin et al ( 2014 ). Inorganic Cd (nitrate/nitrite, chloride, and aminophenol forms of Cd) were extracted with 80% ethanol. Water-soluble Cd (organic acid complexes and Cd(H 2 PO 4 ) 2 ) were extracted with dH 2 O. Cd integrated with pectate and protein was extracted with 1 M NaCl. Water-insoluble CdHPO 4 , Cd 3 (PO 4 ) 2 , and other Cd-phosphate complexes were extracted with 2% acetic acid (HAc). Cd oxalate was extracted with 0.6 M HCl. Cd in residues were also analyzed. Statistical analysis and data processing Calculation of bioconcentration factor (BCF) and transfer factor (TF) To investigate Cd uptake and translocation by plant, the BCF and TF was studied. BCF was calculated as the ratio of Cd concentration in plant organs to soil available Cd concentration. TF indicated the ability of Cd translocation, was defined as the ratio of Cd concentration in one organ to that in another organ. Cd accumulated in one organ was defined the cadmium concentration of one organ multiplied by the dry matter of that organ. Cd distribution in organ means Cd accumulated in one organ divided by cadmium accumulation in the whole plant. Statistical analysis All statistical analyses were performed using SAS8.0. Significant differences were determined using three-way analysis of variance (ANOVA), followed by Duncan’s multiple range test for multiple comparisons between different treatments and genotypes. Statistical significance was set at p < 0.05. Graphs were generated using MS Excel 2017 and R (version 3.3.1; R Development Core Team, Austria). Results Dry matter in different organs There were significant cultivar (C) and N level (N) effects for almost all traits, but no effect of Cd or related interactions for most traits (Table 1 ). Increase in soil Cd level to 1.5 mg∙kg − 1 had no effect on dry matter compare to the 0.5 mg∙kg − 1 Cd level. Chuannong30 had significantly higher root, leaf, and stem dry weights than Chuanmai88, although there was no significant difference in the total dry matter between cultivars, husk and grain weights were higher in Chuanmai88 than in Chuannong30 (Table 1 ). Additionally, the dry matter of all organs increased with increasing N fertilization rates until N rate reached 135 kg∙ha − 1 . Importantly, the highest grain yield was obtained in the N 180 treatment. Compared with those in the N 0 treatments, total dry matter weight increased by 32.36, 64.65, 70.69, 72.24, and 60.43% in the N 45 , N 90 , N 135 , N 180 , and N 225 , respectively. Table 1 Dry matter in different organs of wheat grown with different Cd and N level (g stem − 1 ) Item Root Leaf Stem Husk Grain Sum Cd 0.5 0.187 a 0.404 a 1.433 a 0.541 a 1.552a 4.216 a 1.5 0.184 a 0.404 a 1.435 a 0.554 a 1.564a 4.222 a C Chuanmai88 0.179 b 0.333 b 1.424 b 0.587 a 1.653 a 4.178 a Chuannong30 0.192 a 0.474 a 1.483 a 0.508 b 1.503 b 4.160 a N level N 0 0.164 de 0.308 d 1.055 e 0.364 d 0.887 e 2.778 d N 45 0.185 c 0.374 c 1.352 d 0.480 c 1.285 d 3.677 c N 90 0.198 b 0.458 a 1.643 a 0.599 b 1.629 c 4.574 b N 135 0.233 a 0.460 a 1.651 a 0.632 a 1.857 b 4.742 a N 180 0.178 cd 0.412 b 1.574 b 0.618 ab 1.957 a 4.785 a N 225 0.155 e 0.410 b 1.446 c 0.594 b 1.851 b 4.457 b Significant(F Value) Cd 0.0 0.1 1.0 3.8 1.8 1.1 C 6.6 * 436.1 *** 13.3 *** 94.7 *** 34.7 *** 0.1 Cd×C 5.7 * 1.6 0.8 5.8 * 0.6 1.3 N 30.4 *** 45.4 *** 126.4 *** 115.1 *** 177.6 *** 191.9 *** Cd×N 0.7 1.3 1.1 1.7 0.5 1.0 C×N 2.7 * 1.7 5.4 3.0 * 2.9 * 3.1 * Cd×V×N 2.4 * 3.3 3.9 2.3 0.9 2.6 * Different letters after data indicate significant differences between Cd treatments, cultivars and N levels at P < 0.05, respectively. * , ** and *** Significant at 0.05, 0.01 and 0.001 levels, respectively. Cd concentration, accumulation, and distribution in different organs Table 2 showed the Cd concentration and accumulation in different organs. We observed significant Cd, C, N level effects for almost all traits. Additionally, we observed a significant Cd×C interaction, except for Cd concentration in leaves and stems and accumulation in roots; a significant Cd×N interaction, except for Cd concentration in roots and stems; a significant C×N interaction, except for Cd concentration in stems and accumulation in roots and leaves; and a significant Cd×C×N interaction, except for Cd concentration in roots and accumulation in roots, stems, and leaves. Table 2 Cd concentrations and accumulations in different organs of Chuanmai88 and Chuannong30 grown with different Cd and N level Item Cadmium concentration (mg kg − 1 ) Cadmium accumulation (µg stem − 1 ) Root Leaf Stem Husk Grain Root Leaf Stem Husk Grain Cd 0.5 0.313 b 0.167 b 0.083 b 0.048 b 0.046 b 60.0 b 69.6 b 116.7 b 27.1 b 77.6 b 1.5 0.812 a 0.354 a 0.188 a 0.108 a 0.153 a 151.6 a 147.4 a 293.8 a 64.2 a 270.9 a C Chuanmai88 0.616 a 0.263 a 0.153 a 0.095 a 0.130 a 112.2 a 92.1 b 243.4 a 59.7 a 234.8 a Chuannong30 0.509 b 0.259 a 0.117 b 0.060 b 0.070 b 99.4 b 124.9 a 167.1 b 31.6 b 113.7 b N level N 0 0.531 d 0.197 f 0.093 e 0.053 e 0.065 f 86.2 d 63.3 d 107.1 d 20.9 f 55.6 e N 45 0.531 d 0.225 e 0.114 d 0.056 e 0.073 e 100.5 c 77.6 c 155.0 c 28.6 e 99.4 d N 90 0.537 cd 0.232 d 0.132 cd 0.073 d 0.094 d 132.8 a 113.1 b 219.0 b 43.0 d 164.4 c N 135 0.553 bc 0.285 c 0.145 bc 0.070 c 0.095 c 117.4 b 117.8 b 241.6 ab 49.3 c 211.2 b N 180 0.593 ab 0.304 b 0.153 ab 0.096 b 0.121 b 108.7 bc 140.4 a 253.6 a 60.5 b 249.2 a N 225 0.631 a 0.322 a 0.175 a 0.118 a 0.139 a 103.9 c 138.9 a 255.2 a 71.8 a 265.6 a Significant(F Value) Cd 2112.3 *** 721.7 *** 255.0 *** 739.4 *** 1832.6 *** 998.6 *** 386.9 *** 456.3 *** 617.2 *** 777.9 *** C 96.7 *** 0.3 30.3 *** 256.6 *** 658.8 *** 23.0 *** 66.0 *** 83.5 *** 346.2 *** 2025.5 *** Cd×C 23.4 *** 1.8 1.4 52.7 *** 156.6 *** 3.7 14.3 *** 4.6 * 92.8 *** 204.2 *** N 9.7 *** 29.3 *** 13.1 *** 86.8 *** 75.3 *** 18.2 *** 43.2 *** 35.1 *** 106.5 *** 246.4 *** Cd×N 1.8 9.2 *** 1.9 20.1 *** 21.0 *** 5.1 *** 8.4 *** 6.6 *** 20.4 *** 17.8 *** C×N 2.5 * 5.6 *** 1.5 15.2 *** 8.8 *** 1.0 1.4 3.6 ** 17.7 *** 72.9 *** Cd×V×N 1.4 5.9 *** 7.0 *** 3.9 ** 3.3 * 1.3 2.0 1.9 4.8 ** 3.2 * Different letters after data indicate significant differences between Cd treatments, cultivars and N levels at P leaf > stem > grain > husk, and Cd accumulations in Chuanmai88 and Chuannong30 were in the order of stem > grain > root > leaf > husk and stem > leaf > grain > root > husk, respectively. Cd concentration and accumulation in all the organs of both cultivars increased with increasing soil Cd levels. Grain Cd concentration in all treatments was less than 0.1 mg∙kg − 1 (Cd concentration threshold in wheat, China. Standard number: GB 2762–2017) at soil Cd level of 0.5 mg∙kg − 1 , while Cd concentration of Chuannong30 in the N 135 group was lower than the safety threshold at soil Cd level of 1.5 mg∙kg − 1 (Fig. 1 ). Chuanmai88 showed significantly higher Cd concentration and accumulation in all organs than Chuannong30, except in the leaves. Specifically, root, stem, husk, and grain Cd concentrations were higher in Chuanmai88 than in Chuannong30 by 11.80, 66.36, 46.68, and 105.88%, respectively, under at soil Cd level of 0.5 mg∙kg − 1 , and by 23.62, 39.06, 59.44, and 99.08%, respectively, at Cd level of 1.5 mg∙kg − 1 (Table S1 ). Similarly, Cd accumulation rates were higher in the roots, stems, husks, and grains of Chuanmai88 than in those of Chuannong30 by 14.16, 62.98, 62.42, and 119.51%, respectively, at soil Cd level of 0.5 mg∙kg − 1 , and by 12.73, 39.32, 94.62, and 124.16%, respectively, at Cd level of 1.5 mg∙kg − 1 . Regarding N levels, Cd concentration and accumulation in all organs increased significantly with increasing N levels. Compared with that in the N 0 group, grain Cd concentration increased by 17.82, 50.46, 68.26, 90.09, and 115.86%, in the N 45 , N 90 , N 135 , N 180 , and N 225 groups. Additionally, Cd accumulation in grains increased by 78.66, 195.56, 279.67, 348.03, and 377.42% in the N 45 , N 90 , N 135 , N 180 , and N 225 groups, respectively, compared with that in the N 0 group (Table S1 ). Correlation analysis revealed that the Cd concentrations of all organs were positively correlated, and the correlation coefficients between grain and other organs were in the order of stem > husk > root > leaf (Fig. S1 ). Furthermore, there were differences in the distribution of Cd among the different cultivars and organs (Fig. 2 ). Based on the average under varying soil Cd and N levels, the stem and grain of Chuanmai88 accounted for the highest proportion (34.22 and 28.43% respectively), followed by the root (15.97%), leaf (13.72%), and husk (7.67%). Additionally, the proportion Cd distribution in the grains increased with increasing N levels, whereas the roots and leaves showed the opposite trend. For Chuannong30, the proportion of total Cd in each organ was in the order of stem (26.76%) > leaf (26.23%) > root (21.29%) > grain (18.63%) > husk (6.16%). BCF and TF There was a significant N level and C effects for BCF in all organs (except cultivar effect for leaves), we also observed a significant Cd effect for BCF in leaves, husks, and grains; Cd × C interaction for BCF in leaves and stems, Cd × N interaction for BCF in grains, C × N interaction for BCF in husks and grains, and Cd × V × N interaction for BCF in stems and grains (Table 3 ). Table 3 BCF and transfer factors (TF) between different organs of Chuanmai88 and Chuannong30 grown with different Cd and N level Item BCF TF Leaf Stem Husk Grain Root Root-stem Stem-leaf Stem-husk Root-grain Husk-grain Leaf-grain Stem-grain Cd 0.5 0.991 a 0.513 a 0.292 a 0.278 b 1.906 a 0.250 a 1.746 b 0.759 a 0.142 b 0.953 b 0.265 b 0.674 b 1.5 0.784 b 0.483 a 0.251 b 0.333 a 1.896 a 0.241 a 4.038 a 0.661 b 0.192 a 1.577 a 0.449 a 1.023 a C Chuanmai88 0.887 a 0.542 a 0.327 a 0.391 a 1.981 a 0.281 a 1.709 b 0.576 b 0.209 a 1.461 a 0.468 a 0.778 b Chuannong30 0.888 a 0.454 b 0.216 b 0.220 b 1.761 b 0.203 b 2.447 a 0.871 a 0.125 b 1.070 b 0.246 b 0.920 a N level N 0 0.669 e 0.333 e 0.176 e 0.179 f 1.629 c 0.178 e 3.323 a 0.674 b 0.118 d 1.177 a 0.319 d 0.886 a N 45 0.722 d 0.375 e 0.197 de 0.220 e 1.727 bc 0.208 d 2.879 b 0.677 ab 0.136 d 1.292 a 0.335 cd 0.778 a N 90 0.824 c 0.462 d 0.240 cd 0.288 d 1.815 bc 0.243 c 2.855 b 0.701 ab 0.168 c 1.332 a 0.343 bc 0.826 a N 135 0.938 c 0.524 c 0.249 c 0.327 c 1.876 b 0.258 bc 2.813 b 0.747 ab 0.178 bc 1.341 a 0.367 ab 0.827 a N 180 1.039 b 0.612 b 0.339 b 0.375 b 2.031 ab 0.278 ab 2.783 b 0.732 ab 0.194 ab 1.239 a 0.369 ab 0.900 a N 225 1.133 a 0.684 a 0.428 a 0.444 a 2.148 a 0.287 a 2.700 b 0.766 a 0.207 a 1.211 a 0.398 a 0.875 a Significant(F Value) Cd 51.6 *** 2.9 20.8 *** 43.8 *** 3.5 3.5 24.9 *** 8.9 ** 176.5 *** 246.7 *** 350.8 *** 82.6 *** C 0.3 20.5 *** 133.0 *** 462.0 *** 13.5 *** 85.3 *** 419.9 *** 89.7 *** 495.8 *** 88.3 *** 494.7 *** 11.4 ** Cd×C 8.2 ** 26.7 *** 0.7 3.7 0.0 16.9 *** 8.3 ** 14.4 *** 0.1 0.5 41.8 *** 0.2 N 20.1 *** 33.2 *** 66.4 *** 102.3 *** 8.0 *** 13.7 *** 2.8 * 1.4 54.6 *** 1.8 5.2 *** 1.1 Cd×N 1.3 0.3 0.6 4.2 ** 0.6 0.3 0.7 0.6 1.0 2.4 2.7 * 2.2 C×N 0.8 0.9 10.2 *** 3.5 ** 0.7 2.1 1.7 1.5 1.7 5.6 *** 0.6 1.1 Cd×C×N 1.0 2.5 * 1.4 6.9 *** 1.2 1.2 0.8 1.7 1.6 4.0 ** 2.7 * 1.2 Different letters after data indicate significant differences between Cd treatments, cultivars and N levels at P leaf > stem > grain > husk (Table 3 ). An increase in soil Cd concentration decreased BCF in leaves and husks but increased it in grains. Chuanmai88 showed significantly higher BCF in all organs than Chuannong30, except in leaves. Additionally, the BCF of all organs increased with increasing N levels. Compared with that in the N 0 group, the BCF of the root of Chuanmai88 increased by 8.74, 12.70, 14.59, 27.21, and 37.12% in the N 45 , N 90 , N 135 , N 180 , and N 225 groups, and that of Chuannong30 increased by 3.26, 10.30, 16.07, 22.17, and 26.09%, respectively (Table S2 ). TF was used to measure Cd transport and redistribution between different organs (Table 3 ). Importantly, we observed significant Cd, C, Cd×C effects for TF in most organs. Specifically, there were differences in chelating ability, with the stem exhibiting the strongest Cd chelating ability, TF stem−leaf and TF husks−grain values were the highest. TF values increased between various organs with increasing soil Cd concentration, except for TF root−stem and TF stem−husk . Chuanmai88 showed higher TF root−stem , TF root−grain , TF husk−grain and TF leaf−grain values than Chuannong30. Additionally, TF values increased between various organs with increasing N levels, except for TF stem−leaf , TF rachis−grain and TF stem−grain . Grain Cd concentrations were extremely significantly positively correlated with TF root−grain , TF husk−grain and TF leaf−grain , with correlation coefficients of 0.84, 0.79, and 0.86, respectively. Cd concentrations in the grains were also significantly positively correlated with TF stem−grain (R = 0.47 * ) and significantly negatively correlated with TF stem−leaf and TF stem−husk (Fig. S2 ). Chemical forms of Cd in plant roots and leaves The concentrations of different chemical forms of Cd in the roots and leaves of Chuanmai88 and Chuannong30 under different Cd and N levels are shown in Fig. 3 and Fig. 4 . the concentrations of different chemical forms of Cd in all organs of the two cultivars increased with increasing soil Cd concentrations. On average, the 80% ethanol Cd fraction and residual fractions were predominant in all treatments, representing more than 90% of the total Cd in different organs. In contrast, the proportion of Cd extracted by any one of other four extracting agents was lower than 10% (Fig. 3 ). In leaves (Fig. 4 ), there was no significant difference ( p > 0.05) in the amount of Cd extracted by 80% ethanol, dH 2 O, and 2%Hac between cultivars following exposure to identical N levels at 0.5 mg∙kg − 1 Cd level, the concentrations of Cd extracted by 1 M NaCl and 0.6 M HCl were significantly higher in Chuanmai88 than in Chuannong30, especially under increasing N levels, while residual Cd fraction was higher in Chuanmnong30 than in Chuanmai88. At 1.5 mg∙kg − 1 Cd level, all chemical forms of Cd (except residual fraction) increased with increasing N levels, with remarkably higher concentrations of the Cd forms in Chuanmai88 than in Chuannong30, the proportions of different chemical forms of Cd in the two cultivars showed similar trends at different Cd levels. Moreover, the proportion of the ethanol fraction was highest, followed by the residual, dH 2 O, and the 2% Hac (lowest) fractions. Furthermore, all chemical forms, except residual Cd fraction, were higher in Chuanmai88 than in Chuannong30 (Fig. 3 ). In roots (Fig. 4 ), there was no significant difference in all the chemical forms (except residual-extracted) between cultivars and N levels at 0.5mg kg − 1 Cd level, while all chemical forms (except residual-extracted) increase with increasing of N levels at soil Cd level of 1.5 mg∙kg − 1 , whereas residual Cd fraction showed the opposite trend. the concentrations of 80% ethanol fraction, dH 2 O fraction, 1 M NaCl fraction, and 2% Hac fraction were significantly higher in Chuanmai88 than Chuannong30. Notably, the proportion of 80% ethanol fraction was the highest (79.78%), followed by that of the residual (12.39%), dH 2 O (5.47%), and 0.6 M HCl fractions (0.21%). All chemical forms, except residual Cd, were higher in Chuanmai88 than in Chuannong30 (Fig. 3 ). Soil pH, CEC, and available Cd concentration As shown in Fig. 5 (a), the pH of soils used in growing both cultivars showed a decrease with increasing soil Cd levels. Although soil pH was higher in the Chuannong30 group than in the Chuanmai88 group at all N levels, it showed a general decrease with increasing N levels. Compared with that in the N 0 group, the pH values of soils used in growing Chuannong30 and Chuanmai88 were significantly lower in the N 180 and N 90 , respectively. As shown in Fig. 5 (b), CEC showed significantly lower value at 0.5 mg∙kg − 1 Cd level than at 1.5 mg∙kg − 1 Cd level. Additionally, the CEC of soils using in growing both cultivars increased with increasing N fertilization rate. Generally, the Chuanmai88 had a higher CEC than did the Chuannong30. Soil available Cd increased with increasing N levels at both Cd levels (Fig. 5 c, d). Soil available Cd was higher in the Chuanmai88 than in the Chuannong30 under all treatment conditions. Correlation analysis showed that soil-available Cd was positively correlated with grain Cd content (Table S1 ). Cd species in soil Cd distribution is a criterion for assessing its mobility and toxicity in the soil environment. Figure 6 showed the percentage fractions of Cd species in the N and Cd treatments. At 0.5 mg∙kg − 1 Cd level, the concentrations of different Cd species were in the order of residual Cd (36.13%) > Fe-Mn oxide associated Cd (26.18%) > exchangeable Cd (14.34%) > carbonate associated Cd (12.02%) > organic matter associated Cd (11.33%). Exchangeable Cd and carbonate associated Cd increased with increasing N levels, there were no significant differences in Fe-Mn oxide associated Cd among the N levels, in contrast, organic matter associated Cd and residual Cd showed decreasing trend with increasing N levels. Chuanmai88 showed higher exchangeable Cd and carbonate associated Cd and lower residual Cd than Chuannong30. At soil Cd concentration of 1.5 mg∙kg − 1 , there was a remarkable increase in exchangeable Cd and carbonate-associated Cd and a decrease in residual Cd. Notably, the order of fractions from high to low was as follows: exchangeable Cd (33.93%) > Fe-Mn oxide associated Cd (27.79%) > residual Cd (14.12%) > carbonate associated Cd (13.37) > organic matter associated Cd (10.78%). Exchangeable and carbonate-associated Cd increased with increasing N levels, whereas Fe-Mn oxide-associated Cd, organic matter-associated Cd, and residual Cd showed a decreasing trend. Chuanmai88 showed higher exchangeable Cd and carbonate-associated Cd than Chuannong30. In contrast, Chuannong30 showed a higher proportion of the other Cd species than Chuanmai88. Discussion N fertilization can be effectively managed to reduce Cd contamination in the food chain. In this study, the Cd concentrations of wheat grain grown in soil polluted with Cd (0.5 mg∙kg − 1 ) were lower than the safety threshold. In contrast, only the low grain-Cd-accumulating cultivar Chuannong30 in the N 0 , N 45 , N 90 , and N 135 groups had safe Cd levels under soil Cd levels of 1.5 mg∙kg − 1 (Fig. 1 , Table S1 ). Both Cd levels did not affect wheat growth and grain yield, indicating that the amount of Cd had no toxic effects on plants. Wheat in the N 180 level had the highest grain yield (Table 1 , S1). Overall, these results indicate that improved wheat yield with safe Cd levels can be achieved in low-Cd soils under N fertilization rate of 180 kg∙ha − 1 N. Additionally, low grain-Cd-accumulating wheat varieties can safely be grown in soils with Cd concentration of 1.5 mg∙kg − 1 under N fertilization rates < 135 kg∙ha − 1 . However, further studies are necessary to examine whether wheat yield can be further increased by improving N use efficiency (Shan et al. 2023 ). Consistent with previous findings (Weng et al. 2012 ), plants grown in high Cd soil showed higher Cd accumulation in various organs, BCF in grains, TF root−grain value, and ethanol and dH 2 O Cd fractions, and lower residual Cd in roots and leaves. Additionally, increasing soil Cd reduced soil pH and increased soil available Cd and CEC. N is a vital nutrient for the plant physiological metabolism, growth, and development of plants, and alleviates the toxic effects of Cd stress (Gao et al. 2019 ). N fertilization significantly influences the absorption of Cd by crops (Yang et al. 2016 ). In the present study, N fertilization at 135–180 kg∙ha − 1 prominently enhanced grain yield under both low and high soil Cd levels (Table 1 ), Similarly, previous studies reported that increased N fertilization upregulated Cd absorption and accumulation in plants, with positive correlation observed between N fertilization rate and Cd accumulation (Fig. 1 and Table S1 ) (Li et al. 2011 ; Özkutlu et al. 2024). N fertilizer promotes crop nutritional status, improves crop growth, and increases soil ion exchange reactions, result in increased Cd accumulation in plants (Yang et al. 2020 ). Generally, Low grain Cd accumulators can uptake less Cd from the soil than high grain accumulators (Greger and Landberg 2008 ), this study reached a similar conclusion. Although Chuannong30 showed higher root, stem, and leaf dry matter than Chuanmai88, it had lower Cd concentrations in all organs (except in the leaves) (Table 2 ), therefore, Cd accumulation in various organs (except leaf) were higher in Chuanmai88. Cd concentrations in different organs of wheat cultivars varied under both Cd levels. Cd concentration in the organs was in the order of root > leaf > stem > grain > husk. High Cd concentration in the root (47.4–51.3%) indicates that only a fraction of the Cd was transported to the other tissues (Kunene et al. 2020 ). Although there was no significant difference in leaf Cd concentration between Chuannong30 and Chuanmai88, Chuannong30 had a higher leaf dry weight and Cd accumulation. High Cd accumulation in the leaves of Chuannong30 may be responsible for low Cd concentration in the grains. A previously study in rice also showed that transport from leaf to brown rice is the most important determinant of Cd concentration in grain (Luo et al. 2022 ). In addition, grain Cd concentration was significantly positively correlated with Cd concentration in different organs, indicating the close transport relationships among the different organs of wheat (Fig. S1 ) (Zhen et al. 2021 ; Liu et al. 2021 ; Wang et al. 2021 ; Huang et al. 2023 ). Cd transport from soil to crops can be divided into two processes: soil Cd transport to the roots, and Cd absorb by roots and translocation to aerial parts. BCF in grains can be used to estimate the Cd accumulation capacity of plants, and TF is used to evaluate Cd transport and redistribution between different organs (Bai et al. 2023 ). Li and Zhou ( 2019 ) reported variations in the BCF values for the safe production of wheat grains grown on Cd-polluted soil under different pH levels (pH < 7.5, BCF 7.5, BCF < 0.167). In the present study, N fertilization enhanced the BCF in all organs, with the BCF of the grains of Chuannong30 grown in high soil Cd conditions under N fertilization rates < 135 kg∙ha − 1 being < 0.333, further indicating that low grain-Cd-accumulating wheat can be grown in Cd contaminated soils under N fertilization rates < 135 kg∙ha − 1 , without Cd toxicity (Table 3 ). Additionally, there was no significant difference in the BCF of leaves between the two cultivars, indicating similar ability of leaves to accumulate Cd from the soil in both cultivars, however, the BCF in other organs of Chuanmai88 was significantly higher than those of Chuannong30, indicating a higher Cd accumulation capacity in Chuanmai88 (Table 3 ). Additionally, the higher TF root−stem , TF root−grain , TF husk−grain , and TF leaf−grain values of Chuanmai88 indicates that it should have a superior translocation ability (Table 3 ), contributing to a higher Cd accumulation in the grain. In contrast, the high TF stem−leaf and TF stem−husk values of Chuannong30 suggest low Cd translocation to the grain. Moreover, F leaf−grain , TF root−grain , TF husk−grain , and TF stem−grain values were remarkably positively correlated with grain Cd concentration and significantly negatively correlated with TF stem−leaf and TF stem−husk values (Fig. S2 ). with TF leaf−grain having the highest correlation with grain Cd concentration. Collectively, these results manifest that Cd transport from leaf to grain has an important impact on grain Cd concentration. Based on Cd distribution in different organs (Fig. 2 .), stems and grains showed the highest Cd accumulation in Chuanmai88, with grain Cd accumulation accounting for approximately 28.4% of total Cd accumulation. Additionally, stem and leaf showed the highest Cd accumulation in Chuannong30, with Cd accumulation in grain accounted for approximately 18.6% of the whole plant. Overall, these results indicate that Chuannong30 has a lower Cd absorption and translocation ability than Chuanmai88, with most translocated Cd being stored in roots and leaves. Furthermore, the chemical form of Cd in plants is directly related to its activity, toxicity, and migratory ability (Wang et al. 2015 ). Notably, ethanol and dH 2 O Cd fractions have a higher migratory ability and toxicity than other fractions (Weng et al. 2012 ), as confirm in this study (Fig. 3 ). N fertilization increased all chemical forms of Cd, except for residual Cd, which upregulated the translocation factor from the root to shoot, especially under soil Cd level of 1.5 mg∙kg − 1 (Fig. 4 ; Table 3 ). Increased N supply in high Cd concentrations can improve Cd absorption, accumulation and mobilization by affecting the expression of Cd-chelating N compounds (Yang et al. 2020 ). Although no significant difference was found in concentrations of all Cd forms between cultivars and N levels at 0.5 mg∙kg − 1 Cd level, there was a decrease in the proportion of the residual fraction and a significant increase in all other chemical forms in soils contaminated with Cd at 1.5 mg∙kg − 1 (Fig. 4 ). Additionally, the ethanol fraction occupied the largest proportion of Cd in all organs in both cultivars. Moreover, the proportions of high-mobility Cd extracted by 80%ethanol and dH 2 O were higher in the root of Chuanmai88 than that in Chuannong30 under all the treatments, which may have contributed to the high TF root−shoot value in Chuanmai88 (Table 3 ), ethanol and dH 2 O Cd fractions represent inorganic Cd, soluble Cd salts of organic acids and dihydric phosphates and which are more contaminate to plant cells. the result implies that Chuanmai88 has more free Cd ions, which may be transported to aboveground organs. An increase in N fertilizer improves the activation of roots and organic acid secretion, reduces soil pH, increases CEC soil Cd bioavailability (Fig. 5 ; Liu et al. 2015 ; Wen et al. 2017 ; Shan et al. 2023 ). Soil Cd bioavailability was lower in the Chuannong30 than in the Chuanmai88, especially in soils contaminated with Cd at 1.5 mg∙kg − 1 . the lower soil Cd bioavailable in the Chuannong30 could be attributed to the higher soil negative charge and pH value and lower CEC, which suppressed Cd adsorption by soil particles (Fig. 5 ; Hong et al. 2010 ; Seshadri et al. 2017 ); Soil pH is regarded a dominating factor controlling soil Cd availability, and CEC can evaluate the Cd adsorption ability of soils. Considering that increased soil pH is beneficial to the adsorption of Cd to metal binding sites and reduces the partition of Cd to soil solution (Bai et al. 2023 ), the change of pH may be closely related to soil acidification, ion exchange reaction, and plant physiological processes. Consistent with previous findings (Wang et al. 2021 ; Huang et al. 2023 ), grain Cd content was significantly positively correlated with soil Cd bioavailability (Fig. S1 ). In addition, high soil Cd levels was associated with increased Cd migration ability, decreased concentration of stable form of soil Cd, and increased Cd accumulation in crops (Fig. 6 ), the exchangeable fraction is considered as an primary indicator for estimating the harm of Cd contaminate and observed the most significant increase. Chuanmai88 showed higher exchangeable Cd and carbonate-associated Cd than Chuannong30, and Chuannong30 seemed less sensitive to N level than Chuanmai88 under both Cd levels (Fig. 6 ), indicating the cultivars with high cadmium content with the increase of soil N content promotes the activation of the cadmium migration in the soil, resulting in the accumulation of more Cd in plant. Conclusions Moderate increase in the application of N fertilizer (N 135 to N 180 ) improves grain yield and regulates grain Cd content in wheat. N fertilization reduced soil pH, increased CEC and soil Cd bioavailability, upregulated Cd uptake, accumulation, and translocation, and elevated the proportion of high-mobility Cd extracted by ethanol and dH 2 O. Moreover, there were significant differences in Cd absorption, translocation, chemical forms, and soil Cd bioavailability between the low- and high-Cd wheat cultivars, the low-Cd cultivar had lower Cd accumulation in the grain than the high-Cd cultivar, which may be attributed to several factors, including low Cd translocation from leaf to grain, the chemical form of Cd in the cultivar, lower proportions of ethanol and dH 2 O Cd fractions, and lower activation of the Cd migration in the soil. Declarations Ethics approval Not applicable. Consent to participate Not applicable. Consent for publication Not applicable. Competing interests The authors declare no competing interests. Funding This research was funded by the Sichuan Science and Technology Program of China (2022JDRC0033, 2022ZDZX0016, 2021YFYZ0005, 2024NSFSC1223), the China Agriculture Research System (CARS-3), the National Natural Science Foundation of China (32372226, 31972960 and 32001476), and Sichuan Academy of Agricultural Sciences Program (1 + 9KJGG010, 2022ZZCX007). Author contribution All authors contributed to the study conception Data availability Data will be made available on reasonable request. References Ali H, Khan E (2018) What are heavy metals? Long-standing controversy over the scientific use of the term ‘heavy metals’ – proposal of a comprehensive definition. Toxicol Environ Chem 100: 6–19. https://doi.org/10.1080/02772248.2017.1413652. 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Zhu Y, Wang Y, Zheng H, Xiang X, Wang H, Xie M, Liu H, Fang Z, Liu L, Du S (2023) N fertilizers promote abscisic acid-catabolizing bacteria to enhance heavy metal phytoremediation from metalliferous soils. Sci Total Environ 894: 164964. https://doi.org/10.1016/j.scitotenv.2023.164964. Supplementary Files Supplementarydata.docx Graphicalabstract.png Graphical Abstract Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Major Revision 27 Nov, 2024 Reviewers agreed at journal 19 Nov, 2024 Reviewers invited by journal 13 Nov, 2024 Editor invited by journal 08 Nov, 2024 Editor assigned by journal 07 Nov, 2024 First submitted to journal 06 Nov, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5404240","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":377877703,"identity":"4b8017c2-5be2-4666-b633-28d75a95b633","order_by":0,"name":"Xiaoli Wu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1UlEQVRIiWNgGAWjYJCCAwwMFjxAivFBQoUN0VokQFqYDR6cSSPaIgkQwSb5sO0QYbUGN3IMD/yokJDhbzy8rSKB7QADf3t3AgEtaQkHe85I8EgcOFZ2I4HnDoPEmbMb8Goxu5F84ABvmwSPAcMZsxsJEs8YDCRyCWlJbDj4F6qlIMHgMDFakg8chtnCkJBAhBb7M88SDstA/FIskXAgjYegXyTbc4w/vqmwseefcXjjx5//bOT423vxa0EAiQMGIIqHSOUgwN9gQILqUTAKRsEoGEkAAAq6Tg2oIIUMAAAAAElFTkSuQmCC","orcid":"","institution":"Sichuan Academy of Agricultural Sciences","correspondingAuthor":true,"prefix":"","firstName":"Xiaoli","middleName":"","lastName":"Wu","suffix":""},{"id":377877704,"identity":"3d4e3227-270b-424c-bde2-ec3186a82fd5","order_by":1,"name":"Miao Liu","email":"","orcid":"","institution":"Sichuan Academy of Agricultural Sciences","correspondingAuthor":false,"prefix":"","firstName":"Miao","middleName":"","lastName":"Liu","suffix":""},{"id":377877705,"identity":"3bb64690-65ec-4006-8498-8d12739086b0","order_by":2,"name":"Ming Li","email":"","orcid":"","institution":"Sichuan Academy of Agricultural Sciences","correspondingAuthor":false,"prefix":"","firstName":"Ming","middleName":"","lastName":"Li","suffix":""},{"id":377877706,"identity":"89631623-1fa6-4809-9829-df07cccd6428","order_by":3,"name":"Shizhao Li","email":"","orcid":"","institution":"Sichuan Academy of Agricultural Sciences","correspondingAuthor":false,"prefix":"","firstName":"Shizhao","middleName":"","lastName":"Li","suffix":""},{"id":377877707,"identity":"08dfc296-9f41-45db-a6c5-ead6782a0c83","order_by":4,"name":"Tao Xiong","email":"","orcid":"","institution":"Sichuan Academy of Agricultural Sciences","correspondingAuthor":false,"prefix":"","firstName":"Tao","middleName":"","lastName":"Xiong","suffix":""},{"id":377877708,"identity":"b495be81-45f4-47f1-9744-57d35e863a45","order_by":5,"name":"Chaosu Li","email":"","orcid":"","institution":"Sichuan Academy of Agricultural Sciences","correspondingAuthor":false,"prefix":"","firstName":"Chaosu","middleName":"","lastName":"Li","suffix":""},{"id":377877709,"identity":"49200a18-3cee-4312-b5da-dc7010c76d87","order_by":6,"name":"Yonglu Tang","email":"","orcid":"","institution":"Sichuan Academy of Agricultural Sciences","correspondingAuthor":false,"prefix":"","firstName":"Yonglu","middleName":"","lastName":"Tang","suffix":""}],"badges":[],"createdAt":"2024-11-06 16:02:16","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5404240/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5404240/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":71205170,"identity":"10d0639c-ea2d-4503-8d9b-2b7875ecdeb5","added_by":"auto","created_at":"2024-12-12 07:00:42","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":60540,"visible":true,"origin":"","legend":"\u003cp\u003eGrain yield and grain Cd concentration of Chuanmai88 and Chuannong30 grown with different Cd (a at 0.5 mg kg\u003csup\u003e-1\u003c/sup\u003e Cd level, b at 1.5 mg kg\u003csup\u003e-1\u003c/sup\u003e Cd level) and N levels. The orange indicates grain yield, the blue indicates grain Cd concentration. The red dashed line indicates the limit value of Cd content in the Chinese Food Safety Standards (Grain-Cd = 0.1 mg kg\u003csup\u003e-1\u003c/sup\u003e).\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/31ea62341b622d59cb21df5e.png"},{"id":71205175,"identity":"054b2e3d-d486-4e1a-86c9-79f8042e1a4e","added_by":"auto","created_at":"2024-12-12 07:00:42","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":53773,"visible":true,"origin":"","legend":"\u003cp\u003eDistribution of Cd in each organ of Chuanmai88 and Chuannong30 grown with different Cd and N level. Cadmium distribution in each organ represents the proportion of cadmium in this organ to the whole wheat plant.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/bf45ee374f45b22bca382441.png"},{"id":71205750,"identity":"057a4c27-73dc-42f8-b286-5ec7d20ccd20","added_by":"auto","created_at":"2024-12-12 07:08:42","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":64401,"visible":true,"origin":"","legend":"\u003cp\u003ePercentages of different chemical forms in leaf (a) and root (b) of Cd in Chuanmai88 and Chuannong30 grown with different Cd and N level.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/5f2d0d26e4b7c618cd555293.png"},{"id":71205172,"identity":"f873c469-349b-4ed4-a705-2e6818455438","added_by":"auto","created_at":"2024-12-12 07:00:42","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1055941,"visible":true,"origin":"","legend":"\u003cp\u003eConcentrations of different chemical forms of Cd in leaf and root in Chuanmai88 and Chuannong30 grown with different Cd and N levels. Different letters for each cultivar and Cd treatment mean significant differences among different N levels at p＜0.05.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/d69ea5cfacc13628d062941d.png"},{"id":71205173,"identity":"d70e3a8c-e033-418d-82f7-4f8fe477298b","added_by":"auto","created_at":"2024-12-12 07:00:42","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":77825,"visible":true,"origin":"","legend":"\u003cp\u003eSoil pH(a), CEC(b), and available Cd concentration (c at 0.5 mg kg\u003csup\u003e-1\u003c/sup\u003e Cd level, d at 1.5 mg kg\u003csup\u003e-1\u003c/sup\u003e Cd level) at maturity in different wheat cultivars. Different letters for each cultivar and Cd treatment mean significant differences among different N levels at p＜0.05.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/1f70da54ff53b791195d05ce.png"},{"id":71205178,"identity":"44a9e147-1c97-4454-9ffc-60a92937e3fb","added_by":"auto","created_at":"2024-12-12 07:00:42","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":44236,"visible":true,"origin":"","legend":"\u003cp\u003eSequential extraction of Cd in the soil at maturity in different wheat cultivars.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/038a0fd18980c11d33d9ab39.png"},{"id":71206839,"identity":"f132cbdc-44b7-44de-86d6-06a8d47a3dc3","added_by":"auto","created_at":"2024-12-12 07:16:44","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2305991,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/80c82363-eb01-4650-bc64-2098dff983bc.pdf"},{"id":71205174,"identity":"0c4188d7-2a23-4fbf-8cc9-fb68f3cf729c","added_by":"auto","created_at":"2024-12-12 07:00:42","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":97462,"visible":true,"origin":"","legend":"","description":"","filename":"Supplementarydata.docx","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/7b0de88dc0997cbf6bce8ea0.docx"},{"id":71205177,"identity":"aa047c6f-e2ae-4a13-a69f-8ddc04627580","added_by":"auto","created_at":"2024-12-12 07:00:42","extension":"png","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":146026,"visible":true,"origin":"","legend":"\u003cp\u003eGraphical Abstract\u003c/p\u003e","description":"","filename":"Graphicalabstract.png","url":"https://assets-eu.researchsquare.com/files/rs-5404240/v1/0cf02078e450633c21111502.png"}],"financialInterests":"","formattedTitle":"Nitrogen affects and genotypic variation in Cd absorption, translocation and chemical forms in wheat","fulltext":[{"header":"Introduction","content":"\u003cp\u003eCadmium (Cd) is a serious toxic, non-essential element which is affecting approximately 7.75% of farmlands in China (Chen et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2024\u003c/span\u003e;). It is readily absorbed by crops and enters the food chain, and poses a severely threat to food safety (Zhang et al. \u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; EI Rasafi et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Ali and Khan \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Wheat, as a one of most important crops worldwide, have been confirmed to have higher Cd accumulate ability than other corps, mainly via the roots transport to the aboveground parts where it accumulates in the grain, wheat grain-derived products are also a prime source of Cd in humans (Chen et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Shi et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; FAO 2019; Rizwan et al. \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Consequently, it is of great significance to reduce the Cd absorption, translocation in wheat for ensuring human health.\u003c/p\u003e \u003cp\u003eImportantly, Cd accumulation and absorption in wheat grains is affected by many factors, such as soil condition, atmospheric deposition, wheat cultivars and management practices (Liu et al. \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Ma et al. \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Liu et al. \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). N fertilizers play a crucial role in crop growth and grain yield (Yang et al. \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Srivastava et al. \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2019\u003c/span\u003e), N rate is closely related to Cd absorption and tolerance (Ye et al. \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Reasonable N fertilization management is a time-saving, environmental-friendly, cost-effective, and promising strategy to inhibit Cd absorption and alleviate Cd toxicity in wheat (Chen et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2024\u003c/span\u003e; Zhu et al. \u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e2023\u003c/span\u003e; Khatun et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Cheng et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Yang et al. \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), however, N fertilizer is often used in excess to increase yield, although this practice usually results in the production of Cd-contaminated crop in unpolluted soil (Yang et al. \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Lots of studies have exhibited the effect of N fertilizers on Cd uptake in wheat; great majority found a significantly positive relationship between grain Cd concentration and N fertilizer rate, the addition of various types of N fertilizers, for example calcium nitrate, urea, ammonium nitrate and ammonium-nitrogen, could prominently increase wheat grain Cd concentration (Cheng et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Ata-UI-Karim et al. \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Svecnjak et al. \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Li et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2011\u003c/span\u003e; Perilli et al. \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). Li et al. (\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2011\u003c/span\u003e) showed an increase in Cd concentration in wheat grains with increasing N rates, regardless of Cd concentration in both soil and grains. Increasing N rate enhances Cd accumulation and translocation from roots to aboveground parts and promotes Cd accumulation in grain (Larsson and Asp \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2011\u003c/span\u003e). Furthermore, N fertilizer changes the Cd bio-available in soil and accumulation in wheat (Rizwan et al. \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e2016\u003c/span\u003e; Ishikawa et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Li et al. \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2013\u003c/span\u003e). Therefore, optimal N fertilization is vital to manage Cd bioavailability and accumulation in crops.\u003c/p\u003e \u003cp\u003eGenotypic variations have been reported in Cd absorption, transportation, and accumulation abilities in wheat (Chiao et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Yang et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). Low Cd accumulation cultivars of wheat can effectively decrease grain Cd content, which is a useful way to reduce the risk of people consumption (Yang et al. \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). However, related mechanisms of Cd absorption in the wheat grains between cultivars still unclear (Xiao et al. \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Wang et al. \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Low Cd accumulation cultivars is related to heritable properties, such as reduced expression of transport proteins (Zhang et al. \u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e2020\u003c/span\u003e; Lin et al. \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2022a\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003eb\u003c/span\u003e), small root morphological (Liang et al., \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2017\u003c/span\u003e), and less biomass (Liu et al. \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Kubo et al. (\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2016\u003c/span\u003e) exhibited that wheat have various mechanisms to inhibit Cd transportation to grains, and those mechanisms could be independent from biomass partitioning. Additionally, several researchers believed that chemical forms of Cd are closely associated with its accumulation absorption. Xiao et al. (\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e2020\u003c/span\u003e) observed that the proportion of Cd in shoot soluble fraction in high Cd accumulation cultivars were prominently higher than these in low Cd accumulation cultivars. Rhizosphere bacteria influence soil Cd bioavailability and occupy the important position in plant response to Cd stress (Lopes et al. \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Overall, it is valuable to understand the mechanism of different Cd accumulation cultivars in response to varying soil N and Cd levels.\u003c/p\u003e \u003cp\u003eTherefore, this study aimed to investigate the effect of N application rates on the growth, Cd uptake, translocation, and chemical forms in different Cd accumulation wheat cultivars under different Cd levels, and identify the best nitrogen application method for different cultivars.\u003c/p\u003e"},{"header":"Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eStudy site and experimental materials\u003c/h2\u003e \u003cp\u003eSoil was sampled from the 0-20cm layer of a paddy rice field located in Guanghan City (31\u0026deg;69\u0026prime;N, 104\u0026deg;41\u0026prime;W; altitude 450 m), Sichuan Province, southwest China in July 2021. After soil air-drying and sieving through a 2-mm sieve, physical and chemical properties were measured. The soil properties were as follows: pH, 7.62; soil organic matter (SOM), 28.80 g∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; cation exchange capacity (CEC), 7.12 mol∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; total nitrogen (TN), 1.61 g∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; total phosphorus (TP), 1.54 g∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; total potassium (TK), 1.19 g∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; total Cd, 0.501 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; available phosphorus (AP), 7.25 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e; and available K (AK), 103.60 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e.\u003c/p\u003e \u003cp\u003eTwo cultivars with vary Cd uptake, Chuanmai88 and Chuannong30, were selected from 84 wheat cultivars conducted in our previous study (unpublished). Notably, the Cd concentration in Chuanmai88 grains (0.238 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, DW) was 4.175-fold higher than that in Chuannong30 grains (0.057 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, DW) when grown in Cd-contaminated soils. Therefore, Chuanmai88 and Chuannong30 were considered as Cd high and low Cd accumulation cultivars, respectively.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eExperiment design\u003c/h3\u003e\n\u003cp\u003ePot trial was conducted under open-air conditions during two consecutive seasons (2021/2022 and 2022/2023). It was arranged in a completely randomized design consisting of two-factors: two Cd levels (0.5 and 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e soil as cadmium sulfate) and six N levels (0, 45, 90, 135,180, and 225 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e pure N as urea, as the basic fertilizer). Wheat seeds without disease and insects were selected and surface-sterilized into 10% H\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e2\u003c/sub\u003e (w/w) for 12 min, rinsed, then soaked in distilled water overnight, and germinated under room temperatures for 24 h. Pots were filled with 7 kg soil and 18 wheat seeds were sown per plastic pot. Each cultivar was replicated 10 times, making a total of 240 pots. After growing for 2.5 weeks, nine uniform seedlings were retained per pot. Basal fertilizers were added as phosphorus oxide (90 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and potassium chloride (90 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) into soil. All pots were rearranged monthly.\u003c/p\u003e\n\u003ch3\u003eSoil sampling and physicochemical properties analysis\u003c/h3\u003e\n\u003cp\u003eAt maturity, five pots of soil were sampled from the surface (0\u0026ndash;20 cm). soil samples were passed through 0.15, 0.25-, and 2.0-mm sieves and stored in glass containers for physicochemical analysis after air-drying and manual grinding. Soil pH measurement refer to method of Khaliq et al. (\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). SOM were measured using potassium dichromate volumetric method (GB 9834\u0026ndash;1988) and CEC were determined using hexamminecobalt trichloride solution (HJ 889\u0026ndash;2017).\u003c/p\u003e \u003cp\u003eTotal Cd concentration was measured using inductively coupled plasma mass spectrometry (ICP-MS, Thermo Fisher Scientific iCAP RQ, USA). Available Cd concentrations were extracted with DTPA extracting solution under constant shaking for 2 h at a soil: water ratio of 1:20 (w/v). Cd fractions in the soil, including exchangeable Cd, carbonate\u0026ndash;Cd, Fe\u0026ndash;Mn pesticides\u0026ndash;Cd, organic matter\u0026ndash;Cd, and residual Cd, were refer to method of Li et al. (\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2022\u003c/span\u003e).\u003c/p\u003e\n\u003ch3\u003ePlant sampling and Cd concentration analysis\u003c/h3\u003e\n\u003cp\u003eAt maturity, three pots were selected per treatment for plant sampling. Plants were extracted from the soil by manual and divided into the root, stem\u0026thinsp;+\u0026thinsp;sheath (stem), leaf, grain, rachis\u0026thinsp;+\u0026thinsp;husk (husk). All plant samples were stored at 105 \u0026deg;C for 25 min and dried at 70 \u0026deg;C to a constant weight for dry matter, then, the samples were ground, passed through a 0.15-mm sieve and stored in a plastic bag to measure for Cd concentration.\u003c/p\u003e \u003cp\u003eFor chemical forms of Cd in plant determination, plants were harvested from two pots per treatment at anthesis. Roots and leaves were washed using deionized water, followed by the immediate freezing of fresh plant samples in liquid N\u003csub\u003e2\u003c/sub\u003e for analysis. Chemical forms of Cd in roots and leaves were extracted stepwise with five extracts and in residues, according to the described by Xin et al (\u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2014\u003c/span\u003e). Inorganic Cd (nitrate/nitrite, chloride, and aminophenol forms of Cd) were extracted with 80% ethanol. Water-soluble Cd (organic acid complexes and Cd(H\u003csub\u003e2\u003c/sub\u003ePO\u003csub\u003e4\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e) were extracted with dH\u003csub\u003e2\u003c/sub\u003eO. Cd integrated with pectate and protein was extracted with 1 M NaCl. Water-insoluble CdHPO\u003csub\u003e4\u003c/sub\u003e, Cd\u003csub\u003e3\u003c/sub\u003e(PO\u003csub\u003e4\u003c/sub\u003e)\u003csub\u003e2\u003c/sub\u003e, and other Cd-phosphate complexes were extracted with 2% acetic acid (HAc). Cd oxalate was extracted with 0.6 M HCl. Cd in residues were also analyzed.\u003c/p\u003e\n\u003ch3\u003eStatistical analysis and data processing\u003c/h3\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003eCalculation of bioconcentration factor (BCF) and transfer factor (TF)\u003c/h2\u003e \u003cp\u003eTo investigate Cd uptake and translocation by plant, the BCF and TF was studied. BCF was calculated as the ratio of Cd concentration in plant organs to soil available Cd concentration. TF indicated the ability of Cd translocation, was defined as the ratio of Cd concentration in one organ to that in another organ. Cd accumulated in one organ was defined the cadmium concentration of one organ multiplied by the dry matter of that organ. Cd distribution in organ means Cd accumulated in one organ divided by cadmium accumulation in the whole plant.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eAll statistical analyses were performed using SAS8.0. Significant differences were determined using three-way analysis of variance (ANOVA), followed by Duncan\u0026rsquo;s multiple range test for multiple comparisons between different treatments and genotypes. Statistical significance was set at \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Graphs were generated using MS Excel 2017 and R (version 3.3.1; R Development Core Team, Austria).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003eDry matter in different organs\u003c/h2\u003e \u003cp\u003eThere were significant cultivar (C) and N level (N) effects for almost all traits, but no effect of Cd or related interactions for most traits (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Increase in soil Cd level to 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e had no effect on dry matter compare to the 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level. Chuannong30 had significantly higher root, leaf, and stem dry weights than Chuanmai88, although there was no significant difference in the total dry matter between cultivars, husk and grain weights were higher in Chuanmai88 than in Chuannong30 (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Additionally, the dry matter of all organs increased with increasing N fertilization rates until N rate reached 135 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Importantly, the highest grain yield was obtained in the N\u003csub\u003e180\u003c/sub\u003e treatment. Compared with those in the N\u003csub\u003e0\u003c/sub\u003e treatments, total dry matter weight increased by 32.36, 64.65, 70.69, 72.24, and 60.43% in the N\u003csub\u003e45\u003c/sub\u003e, N\u003csub\u003e90\u003c/sub\u003e, N\u003csub\u003e135\u003c/sub\u003e, N\u003csub\u003e180\u003c/sub\u003e, and N\u003csub\u003e225\u003c/sub\u003e, respectively.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDry matter in different organs of wheat grown with different Cd and N level (g stem\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eItem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRoot\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLeaf\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eStem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHusk\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eGrain\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSum\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.187 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.404 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.433 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.541 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.552a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.216 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.184 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.404 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.435 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.554 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.564a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.222 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChuanmai88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.179 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.333 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.424 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.587 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.653 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.178 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChuannong30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.192 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.474 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.483 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.508 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.503 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.160 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eN level\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.164 de\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.308 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.055 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.364 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.887 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.778 d\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e45\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.185 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.374 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.352 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.480 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.285 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.677 c\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e90\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.198 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.458 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.643 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.599 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.629 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.574 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e135\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.233 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.460 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.651 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.632 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.857 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.742 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e180\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.178 cd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.412 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.574 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.618 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.957 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.785 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e225\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.155 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.410 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.446 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.594 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.851 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.457 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eSignificant(F Value)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.6\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e436.1\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e94.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e34.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.8\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e126.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e115.1\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e177.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e191.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.0\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.9\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.1\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;V\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.4\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.6\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003eDifferent letters after data indicate significant differences between Cd treatments, cultivars and N levels at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05, respectively. \u003csup\u003e*\u003c/sup\u003e, \u003csup\u003e**\u003c/sup\u003eand \u003csup\u003e***\u003c/sup\u003e Significant at 0.05, 0.01 and 0.001 levels, respectively.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003eCd concentration, accumulation, and distribution in different organs\u003c/h2\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e showed the Cd concentration and accumulation in different organs. We observed significant Cd, C, N level effects for almost all traits. Additionally, we observed a significant Cd\u0026times;C interaction, except for Cd concentration in leaves and stems and accumulation in roots; a significant Cd\u0026times;N interaction, except for Cd concentration in roots and stems; a significant C\u0026times;N interaction, except for Cd concentration in stems and accumulation in roots and leaves; and a significant Cd\u0026times;C\u0026times;N interaction, except for Cd concentration in roots and accumulation in roots, stems, and leaves.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eCd concentrations and accumulations in different organs of Chuanmai88 and Chuannong30 grown with different Cd and N level\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"11\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eItem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e \u003cp\u003eCadmium concentration (mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"5\" nameend=\"c11\" namest=\"c7\"\u003e \u003cp\u003eCadmium accumulation (\u0026micro;g stem\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRoot\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLeaf\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eStem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eHusk\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eGrain\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eRoot\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eLeaf\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eStem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003eHusk\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eGrain\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.313 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.167 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.083 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.048 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.046 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e60.0 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e69.6 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e116.7 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e27.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e77.6 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.812 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.354 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.188 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.108 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.153 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e151.6 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e147.4 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e293.8 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e64.2 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e270.9 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChuanmai88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.616 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.263 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.153 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.095 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.130 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e112.2 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e92.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e243.4 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e59.7 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e234.8 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChuannong30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.509 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.259 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.117 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.060 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.070 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e99.4 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e124.9 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e167.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e31.6 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e113.7 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eN level\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.531 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.197 f\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.093 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.053 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.065 f\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e86.2 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e63.3 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e107.1 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e20.9 f\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e55.6 e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e45\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.531 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.225 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.114 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.056 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.073 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e100.5 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e77.6 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e155.0 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e28.6 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e99.4 d\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e90\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.537 cd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.232 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.132 cd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.073 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.094 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e132.8 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e113.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e219.0 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e43.0 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e164.4 c\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e135\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.553 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.285 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.145 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.070 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.095 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e117.4 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e117.8 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e241.6 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e49.3 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e211.2 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e180\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.593 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.304 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.153 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.096 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.121 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e108.7 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e140.4 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e253.6 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e60.5 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e249.2 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e225\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.631 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.322 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.175 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.118 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.139 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e103.9 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e138.9 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e255.2 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e71.8 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e265.6 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"6\" nameend=\"c6\" namest=\"c1\"\u003e \u003cp\u003eSignificant(F Value)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2112.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e721.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e255.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e739.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1832.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e998.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e386.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e456.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e617.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e777.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e96.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e30.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e256.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e658.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e23.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e66.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e83.5\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e346.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e2025.5\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e23.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e52.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e156.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e14.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.6\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e92.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e204.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e29.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13.1\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e86.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e75.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e43.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e35.1\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e106.5\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e246.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e20.1\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e21.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e5.1\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e6.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e20.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e17.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.5\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e15.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e3.6\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e17.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e72.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;V\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.9\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.3\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e4.8\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e3.2\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"11\"\u003eDifferent letters after data indicate significant differences between Cd treatments, cultivars and N levels at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05, respectively. \u003csup\u003e*\u003c/sup\u003e, \u003csup\u003e**\u003c/sup\u003eand \u003csup\u003e***\u003c/sup\u003e Significant at 0.05, 0.01 and 0.001 levels, respectively.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAs shown in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and S1, Cd concentration in wheat organs were in the order of root\u0026thinsp;\u0026gt;\u0026thinsp;leaf\u0026thinsp;\u0026gt;\u0026thinsp;stem\u0026thinsp;\u0026gt;\u0026thinsp;grain\u0026thinsp;\u0026gt;\u0026thinsp;husk, and Cd accumulations in Chuanmai88 and Chuannong30 were in the order of stem\u0026thinsp;\u0026gt;\u0026thinsp;grain\u0026thinsp;\u0026gt;\u0026thinsp;root\u0026thinsp;\u0026gt;\u0026thinsp;leaf\u0026thinsp;\u0026gt;\u0026thinsp;husk and stem\u0026thinsp;\u0026gt;\u0026thinsp;leaf\u0026thinsp;\u0026gt;\u0026thinsp;grain\u0026thinsp;\u0026gt;\u0026thinsp;root\u0026thinsp;\u0026gt;\u0026thinsp;husk, respectively. Cd concentration and accumulation in all the organs of both cultivars increased with increasing soil Cd levels. Grain Cd concentration in all treatments was less than 0.1 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Cd concentration threshold in wheat, China. Standard number: GB 2762\u0026ndash;2017) at soil Cd level of 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, while Cd concentration of Chuannong30 in the N\u003csub\u003e135\u003c/sub\u003e group was lower than the safety threshold at soil Cd level of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Chuanmai88 showed significantly higher Cd concentration and accumulation in all organs than Chuannong30, except in the leaves. Specifically, root, stem, husk, and grain Cd concentrations were higher in Chuanmai88 than in Chuannong30 by 11.80, 66.36, 46.68, and 105.88%, respectively, under at soil Cd level of 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and by 23.62, 39.06, 59.44, and 99.08%, respectively, at Cd level of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). Similarly, Cd accumulation rates were higher in the roots, stems, husks, and grains of Chuanmai88 than in those of Chuannong30 by 14.16, 62.98, 62.42, and 119.51%, respectively, at soil Cd level of 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and by 12.73, 39.32, 94.62, and 124.16%, respectively, at Cd level of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. Regarding N levels, Cd concentration and accumulation in all organs increased significantly with increasing N levels. Compared with that in the N\u003csub\u003e0\u003c/sub\u003e group, grain Cd concentration increased by 17.82, 50.46, 68.26, 90.09, and 115.86%, in the N\u003csub\u003e45\u003c/sub\u003e, N\u003csub\u003e90\u003c/sub\u003e, N\u003csub\u003e135\u003c/sub\u003e, N\u003csub\u003e180\u003c/sub\u003e, and N\u003csub\u003e225\u003c/sub\u003e groups. Additionally, Cd accumulation in grains increased by 78.66, 195.56, 279.67, 348.03, and 377.42% in the N\u003csub\u003e45\u003c/sub\u003e, N\u003csub\u003e90\u003c/sub\u003e, N\u003csub\u003e135\u003c/sub\u003e, N\u003csub\u003e180\u003c/sub\u003e, and N\u003csub\u003e225\u003c/sub\u003e groups, respectively, compared with that in the N\u003csub\u003e0\u003c/sub\u003e group (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). Correlation analysis revealed that the Cd concentrations of all organs were positively correlated, and the correlation coefficients between grain and other organs were in the order of stem\u0026thinsp;\u0026gt;\u0026thinsp;husk\u0026thinsp;\u0026gt;\u0026thinsp;root\u0026thinsp;\u0026gt;\u0026thinsp;leaf (Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFurthermore, there were differences in the distribution of Cd among the different cultivars and organs (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Based on the average under varying soil Cd and N levels, the stem and grain of Chuanmai88 accounted for the highest proportion (34.22 and 28.43% respectively), followed by the root (15.97%), leaf (13.72%), and husk (7.67%). Additionally, the proportion Cd distribution in the grains increased with increasing N levels, whereas the roots and leaves showed the opposite trend. For Chuannong30, the proportion of total Cd in each organ was in the order of stem (26.76%)\u0026thinsp;\u0026gt;\u0026thinsp;leaf (26.23%)\u0026thinsp;\u0026gt;\u0026thinsp;root (21.29%)\u0026thinsp;\u0026gt;\u0026thinsp;grain (18.63%)\u0026thinsp;\u0026gt;\u0026thinsp;husk (6.16%).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003eBCF and TF\u003c/h2\u003e \u003cp\u003eThere was a significant N level and C effects for BCF in all organs (except cultivar effect for leaves), we also observed a significant Cd effect for BCF in leaves, husks, and grains; Cd \u0026times; C interaction for BCF in leaves and stems, Cd \u0026times; N interaction for BCF in grains, C \u0026times; N interaction for BCF in husks and grains, and Cd \u0026times; V \u0026times; N interaction for BCF in stems and grains (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eBCF and transfer factors (TF) between different organs of Chuanmai88 and Chuannong30 grown with different Cd and N level\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"13\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eItem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"5\" nameend=\"c6\" namest=\"c2\"\u003e \u003cp\u003eBCF\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"7\" nameend=\"c13\" namest=\"c7\"\u003e \u003cp\u003eTF\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLeaf\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eStem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHusk\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eGrain\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eRoot\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eRoot-stem\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eStem-leaf\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003eStem-husk\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003eRoot-grain\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c11\"\u003e \u003cp\u003eHusk-grain\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c12\"\u003e \u003cp\u003eLeaf-grain\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c13\"\u003e \u003cp\u003eStem-grain\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"13\" nameend=\"c13\" namest=\"c1\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.991 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.513 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.292 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.278 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.906 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.250 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.746 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.759 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.142 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.953 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.265 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.674 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.784 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.483 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.251 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.333 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.896 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.241 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.038 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.661 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.192 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.577 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.449 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e1.023 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"13\" nameend=\"c13\" namest=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChuanmai88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.887 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.542 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.327 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.391 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.981 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.281 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.709 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.576 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.209 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.461 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.468 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.778 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eChuannong30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.888 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.454 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.216 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.220 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.761 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.203 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.447 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.871 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.125 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.070 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.246 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.920 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"13\" nameend=\"c13\" namest=\"c1\"\u003e \u003cp\u003eN level\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e0\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.669 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.333 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.176 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.179 f\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.629 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.178 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.323 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.674 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.118 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.177 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.319 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.886 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e45\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.722 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.375 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.197 de\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.220 e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.727 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.208 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.879 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.677 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.136 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.292 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.335 cd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.778 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e90\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.824 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.462 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.240 cd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.288 d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.815 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.243 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.855 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.701 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.168 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.332 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.343 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.826 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e135\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.938 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.524 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.249 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.327 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.876 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.258 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.813 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.747 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.178 bc\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.341 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.367 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.827 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e180\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.039 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.612 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.339 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.375 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.031 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.278 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.783 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.732 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.194 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.239 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.369 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.900 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003csub\u003e225\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.133 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.684 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.428 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.444 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.148 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.287 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.700 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.766 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.207 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.211 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.398 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.875 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"13\" nameend=\"c13\" namest=\"c1\"\u003e \u003cp\u003eSignificant(F Value)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e51.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e43.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e24.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e8.9\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e176.5\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e246.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e350.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e82.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20.5\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e133.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e462.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13.5\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e85.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e419.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e89.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e495.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e88.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e494.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e11.4\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;C\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.2\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e26.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e16.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8.3\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e14.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e41.8\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eN\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20.1\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e66.4\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e102.3\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.0\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e13.7\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.8\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e54.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e1.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e5.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4.2\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e2.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e2.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e2.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eC\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10.2\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.5\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e5.6\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCd\u0026times;C\u0026times;N\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.5\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6.9\u003csup\u003e***\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e1.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4.0\u003csup\u003e**\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e2.7\u003csup\u003e*\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e1.2\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"13\"\u003eDifferent letters after data indicate significant differences between Cd treatments, cultivars and N levels at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05, respectively. \u003csup\u003e*\u003c/sup\u003e, \u003csup\u003e**\u003c/sup\u003eand \u003csup\u003e***\u003c/sup\u003e Significant at 0.05, 0.01 and 0.001 levels, respectively.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe BCF of the organs followed the order of root\u0026thinsp;\u0026gt;\u0026thinsp;leaf\u0026thinsp;\u0026gt;\u0026thinsp;stem\u0026thinsp;\u0026gt;\u0026thinsp;grain\u0026thinsp;\u0026gt;\u0026thinsp;husk (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). An increase in soil Cd concentration decreased BCF in leaves and husks but increased it in grains. Chuanmai88 showed significantly higher BCF in all organs than Chuannong30, except in leaves. Additionally, the BCF of all organs increased with increasing N levels. Compared with that in the N\u003csub\u003e0\u003c/sub\u003e group, the BCF of the root of Chuanmai88 increased by 8.74, 12.70, 14.59, 27.21, and 37.12% in the N\u003csub\u003e45\u003c/sub\u003e, N\u003csub\u003e90\u003c/sub\u003e, N\u003csub\u003e135\u003c/sub\u003e, N\u003csub\u003e180\u003c/sub\u003e, and N\u003csub\u003e225\u003c/sub\u003e groups, and that of Chuannong30 increased by 3.26, 10.30, 16.07, 22.17, and 26.09%, respectively (Table \u003cspan refid=\"MOESM2\" class=\"InternalRef\"\u003eS2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTF was used to measure Cd transport and redistribution between different organs (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Importantly, we observed significant Cd, C, Cd\u0026times;C effects for TF in most organs. Specifically, there were differences in chelating ability, with the stem exhibiting the strongest Cd chelating ability, TF\u003csub\u003estem\u0026minus;leaf\u003c/sub\u003e and TF\u003csub\u003ehusks\u0026minus;grain\u003c/sub\u003e values were the highest. TF values increased between various organs with increasing soil Cd concentration, except for TF\u003csub\u003eroot\u0026minus;stem\u003c/sub\u003e and TF\u003csub\u003estem\u0026minus;husk\u003c/sub\u003e. Chuanmai88 showed higher TF\u003csub\u003eroot\u0026minus;stem\u003c/sub\u003e, TF\u003csub\u003eroot\u0026minus;grain\u003c/sub\u003e, TF\u003csub\u003ehusk\u0026minus;grain\u003c/sub\u003e and TF\u003csub\u003eleaf\u0026minus;grain\u003c/sub\u003e values than Chuannong30. Additionally, TF values increased between various organs with increasing N levels, except for TF\u003csub\u003estem\u0026minus;leaf\u003c/sub\u003e, TF\u003csub\u003erachis\u0026minus;grain\u003c/sub\u003e and TF\u003csub\u003estem\u0026minus;grain\u003c/sub\u003e.\u003c/p\u003e \u003cp\u003eGrain Cd concentrations were extremely significantly positively correlated with TF\u003csub\u003eroot\u0026minus;grain\u003c/sub\u003e, TF\u003csub\u003ehusk\u0026minus;grain\u003c/sub\u003e and TF\u003csub\u003eleaf\u0026minus;grain\u003c/sub\u003e, with correlation coefficients of 0.84, 0.79, and 0.86, respectively. Cd concentrations in the grains were also significantly positively correlated with TF\u003csub\u003estem\u0026minus;grain\u003c/sub\u003e (R\u0026thinsp;=\u0026thinsp;0.47\u003csup\u003e*\u003c/sup\u003e) and significantly negatively correlated with TF\u003csub\u003estem\u0026minus;leaf\u003c/sub\u003e and TF\u003csub\u003estem\u0026minus;husk\u003c/sub\u003e (Fig. \u003cspan refid=\"MOESM2\" class=\"InternalRef\"\u003eS2\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003eChemical forms of Cd in plant roots and leaves\u003c/h2\u003e \u003cp\u003eThe concentrations of different chemical forms of Cd in the roots and leaves of Chuanmai88 and Chuannong30 under different Cd and N levels are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e. the concentrations of different chemical forms of Cd in all organs of the two cultivars increased with increasing soil Cd concentrations. On average, the 80% ethanol Cd fraction and residual fractions were predominant in all treatments, representing more than 90% of the total Cd in different organs. In contrast, the proportion of Cd extracted by any one of other four extracting agents was lower than 10% (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eIn leaves (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e), there was no significant difference (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05) in the amount of Cd extracted by 80% ethanol, dH\u003csub\u003e2\u003c/sub\u003eO, and 2%Hac between cultivars following exposure to identical N levels at 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level, the concentrations of Cd extracted by 1 M NaCl and 0.6 M HCl were significantly higher in Chuanmai88 than in Chuannong30, especially under increasing N levels, while residual Cd fraction was higher in Chuanmnong30 than in Chuanmai88. At 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level, all chemical forms of Cd (except residual fraction) increased with increasing N levels, with remarkably higher concentrations of the Cd forms in Chuanmai88 than in Chuannong30, the proportions of different chemical forms of Cd in the two cultivars showed similar trends at different Cd levels. Moreover, the proportion of the ethanol fraction was highest, followed by the residual, dH\u003csub\u003e2\u003c/sub\u003eO, and the 2% Hac (lowest) fractions. Furthermore, all chemical forms, except residual Cd fraction, were higher in Chuanmai88 than in Chuannong30 (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eIn roots (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e), there was no significant difference in all the chemical forms (except residual-extracted) between cultivars and N levels at 0.5mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level, while all chemical forms (except residual-extracted) increase with increasing of N levels at soil Cd level of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, whereas residual Cd fraction showed the opposite trend. the concentrations of 80% ethanol fraction, dH\u003csub\u003e2\u003c/sub\u003eO fraction, 1 M NaCl fraction, and 2% Hac fraction were significantly higher in Chuanmai88 than Chuannong30. Notably, the proportion of 80% ethanol fraction was the highest (79.78%), followed by that of the residual (12.39%), dH\u003csub\u003e2\u003c/sub\u003eO (5.47%), and 0.6 M HCl fractions (0.21%). All chemical forms, except residual Cd, were higher in Chuanmai88 than in Chuannong30 (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003eSoil pH, CEC, and available Cd concentration\u003c/h2\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e(a), the pH of soils used in growing both cultivars showed a decrease with increasing soil Cd levels. Although soil pH was higher in the Chuannong30 group than in the Chuanmai88 group at all N levels, it showed a general decrease with increasing N levels. Compared with that in the N\u003csub\u003e0\u003c/sub\u003e group, the pH values of soils used in growing Chuannong30 and Chuanmai88 were significantly lower in the N\u003csub\u003e180\u003c/sub\u003e and N\u003csub\u003e90\u003c/sub\u003e, respectively.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAs shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e(b), CEC showed significantly lower value at 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level than at 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level. Additionally, the CEC of soils using in growing both cultivars increased with increasing N fertilization rate. Generally, the Chuanmai88 had a higher CEC than did the Chuannong30.\u003c/p\u003e \u003cp\u003eSoil available Cd increased with increasing N levels at both Cd levels (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003ec, d). Soil available Cd was higher in the Chuanmai88 than in the Chuannong30 under all treatment conditions. Correlation analysis showed that soil-available Cd was positively correlated with grain Cd content (Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003eCd species in soil\u003c/h2\u003e \u003cp\u003eCd distribution is a criterion for assessing its mobility and toxicity in the soil environment. Figure\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e showed the percentage fractions of Cd species in the N and Cd treatments. At 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level, the concentrations of different Cd species were in the order of residual Cd (36.13%)\u0026thinsp;\u0026gt;\u0026thinsp;Fe-Mn oxide associated Cd (26.18%)\u0026thinsp;\u0026gt;\u0026thinsp;exchangeable Cd (14.34%)\u0026thinsp;\u0026gt;\u0026thinsp;carbonate associated Cd (12.02%)\u0026thinsp;\u0026gt;\u0026thinsp;organic matter associated Cd (11.33%). Exchangeable Cd and carbonate associated Cd increased with increasing N levels, there were no significant differences in Fe-Mn oxide associated Cd among the N levels, in contrast, organic matter associated Cd and residual Cd showed decreasing trend with increasing N levels. Chuanmai88 showed higher exchangeable Cd and carbonate associated Cd and lower residual Cd than Chuannong30. At soil Cd concentration of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, there was a remarkable increase in exchangeable Cd and carbonate-associated Cd and a decrease in residual Cd. Notably, the order of fractions from high to low was as follows: exchangeable Cd (33.93%)\u0026thinsp;\u0026gt;\u0026thinsp;Fe-Mn oxide associated Cd (27.79%)\u0026thinsp;\u0026gt;\u0026thinsp;residual Cd (14.12%)\u0026thinsp;\u0026gt;\u0026thinsp;carbonate associated Cd (13.37)\u0026thinsp;\u0026gt;\u0026thinsp;organic matter associated Cd (10.78%). Exchangeable and carbonate-associated Cd increased with increasing N levels, whereas Fe-Mn oxide-associated Cd, organic matter-associated Cd, and residual Cd showed a decreasing trend. Chuanmai88 showed higher exchangeable Cd and carbonate-associated Cd than Chuannong30. In contrast, Chuannong30 showed a higher proportion of the other Cd species than Chuanmai88.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eN fertilization can be effectively managed to reduce Cd contamination in the food chain. In this study, the Cd concentrations of wheat grain grown in soil polluted with Cd (0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) were lower than the safety threshold. In contrast, only the low grain-Cd-accumulating cultivar Chuannong30 in the N\u003csub\u003e0\u003c/sub\u003e, N\u003csub\u003e45\u003c/sub\u003e, N\u003csub\u003e90\u003c/sub\u003e, and N\u003csub\u003e135\u003c/sub\u003e groups had safe Cd levels under soil Cd levels of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). Both Cd levels did not affect wheat growth and grain yield, indicating that the amount of Cd had no toxic effects on plants. Wheat in the N\u003csub\u003e180\u003c/sub\u003e level had the highest grain yield (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, S1). Overall, these results indicate that improved wheat yield with safe Cd levels can be achieved in low-Cd soils under N fertilization rate of 180 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e N. Additionally, low grain-Cd-accumulating wheat varieties can safely be grown in soils with Cd concentration of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e under N fertilization rates\u0026thinsp;\u0026lt;\u0026thinsp;135 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. However, further studies are necessary to examine whether wheat yield can be further increased by improving N use efficiency (Shan et al. \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Consistent with previous findings (Weng et al. \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), plants grown in high Cd soil showed higher Cd accumulation in various organs, BCF in grains, TF\u003csub\u003eroot\u0026minus;grain\u003c/sub\u003e value, and ethanol and dH\u003csub\u003e2\u003c/sub\u003eO Cd fractions, and lower residual Cd in roots and leaves. Additionally, increasing soil Cd reduced soil pH and increased soil available Cd and CEC.\u003c/p\u003e \u003cp\u003eN is a vital nutrient for the plant physiological metabolism, growth, and development of plants, and alleviates the toxic effects of Cd stress (Gao et al. \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2019\u003c/span\u003e). N fertilization significantly influences the absorption of Cd by crops (Yang et al. \u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). In the present study, N fertilization at 135\u0026ndash;180 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e prominently enhanced grain yield under both low and high soil Cd levels (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e), Similarly, previous studies reported that increased N fertilization upregulated Cd absorption and accumulation in plants, with positive correlation observed between N fertilization rate and Cd accumulation (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and Table\u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e) (Li et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2011\u003c/span\u003e; \u0026Ouml;zkutlu et al. 2024). N fertilizer promotes crop nutritional status, improves crop growth, and increases soil ion exchange reactions, result in increased Cd accumulation in plants (Yang et al. \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Generally, Low grain Cd accumulators can uptake less Cd from the soil than high grain accumulators (Greger and Landberg \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2008\u003c/span\u003e), this study reached a similar conclusion. Although Chuannong30 showed higher root, stem, and leaf dry matter than Chuanmai88, it had lower Cd concentrations in all organs (except in the leaves) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), therefore, Cd accumulation in various organs (except leaf) were higher in Chuanmai88. Cd concentrations in different organs of wheat cultivars varied under both Cd levels. Cd concentration in the organs was in the order of root\u0026thinsp;\u0026gt;\u0026thinsp;leaf\u0026thinsp;\u0026gt;\u0026thinsp;stem\u0026thinsp;\u0026gt;\u0026thinsp;grain\u0026thinsp;\u0026gt;\u0026thinsp;husk. High Cd concentration in the root (47.4\u0026ndash;51.3%) indicates that only a fraction of the Cd was transported to the other tissues (Kunene et al. \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Although there was no significant difference in leaf Cd concentration between Chuannong30 and Chuanmai88, Chuannong30 had a higher leaf dry weight and Cd accumulation. High Cd accumulation in the leaves of Chuannong30 may be responsible for low Cd concentration in the grains. A previously study in rice also showed that transport from leaf to brown rice is the most important determinant of Cd concentration in grain (Luo et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). In addition, grain Cd concentration was significantly positively correlated with Cd concentration in different organs, indicating the close transport relationships among the different organs of wheat (Fig.\u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e) (Zhen et al. \u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Liu et al. \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Wang et al. \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Huang et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eCd transport from soil to crops can be divided into two processes: soil Cd transport to the roots, and Cd absorb by roots and translocation to aerial parts. BCF in grains can be used to estimate the Cd accumulation capacity of plants, and TF is used to evaluate Cd transport and redistribution between different organs (Bai et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Li and Zhou (\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) reported variations in the BCF values for the safe production of wheat grains grown on Cd-polluted soil under different pH levels (pH\u0026thinsp;\u0026lt;\u0026thinsp;7.5, BCF\u0026thinsp;\u0026lt;\u0026thinsp;0.333; pH\u0026thinsp;\u0026gt;\u0026thinsp;7.5, BCF\u0026thinsp;\u0026lt;\u0026thinsp;0.167). In the present study, N fertilization enhanced the BCF in all organs, with the BCF of the grains of Chuannong30 grown in high soil Cd conditions under N fertilization rates\u0026thinsp;\u0026lt;\u0026thinsp;135 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e being \u0026lt;\u0026thinsp;0.333, further indicating that low grain-Cd-accumulating wheat can be grown in Cd contaminated soils under N fertilization rates\u0026thinsp;\u0026lt;\u0026thinsp;135 kg∙ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, without Cd toxicity (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Additionally, there was no significant difference in the BCF of leaves between the two cultivars, indicating similar ability of leaves to accumulate Cd from the soil in both cultivars, however, the BCF in other organs of Chuanmai88 was significantly higher than those of Chuannong30, indicating a higher Cd accumulation capacity in Chuanmai88 (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Additionally, the higher TF\u003csub\u003eroot\u0026minus;stem\u003c/sub\u003e, TF\u003csub\u003eroot\u0026minus;grain\u003c/sub\u003e, TF\u003csub\u003ehusk\u0026minus;grain\u003c/sub\u003e, and TF\u003csub\u003eleaf\u0026minus;grain\u003c/sub\u003e values of Chuanmai88 indicates that it should have a superior translocation ability (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), contributing to a higher Cd accumulation in the grain. In contrast, the high TF\u003csub\u003estem\u0026minus;leaf\u003c/sub\u003e and TF\u003csub\u003estem\u0026minus;husk\u003c/sub\u003e values of Chuannong30 suggest low Cd translocation to the grain. Moreover, F\u003csub\u003eleaf\u0026minus;grain\u003c/sub\u003e, TF\u003csub\u003eroot\u0026minus;grain\u003c/sub\u003e, TF\u003csub\u003ehusk\u0026minus;grain\u003c/sub\u003e, and TF\u003csub\u003estem\u0026minus;grain\u003c/sub\u003e values were remarkably positively correlated with grain Cd concentration and significantly negatively correlated with TF\u003csub\u003estem\u0026minus;leaf\u003c/sub\u003e and TF\u003csub\u003estem\u0026minus;husk\u003c/sub\u003e values (Fig.\u003cspan refid=\"MOESM2\" class=\"InternalRef\"\u003eS2\u003c/span\u003e). with TF\u003csub\u003eleaf\u0026minus;grain\u003c/sub\u003e having the highest correlation with grain Cd concentration. Collectively, these results manifest that Cd transport from leaf to grain has an important impact on grain Cd concentration. Based on Cd distribution in different organs (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.), stems and grains showed the highest Cd accumulation in Chuanmai88, with grain Cd accumulation accounting for approximately 28.4% of total Cd accumulation. Additionally, stem and leaf showed the highest Cd accumulation in Chuannong30, with Cd accumulation in grain accounted for approximately 18.6% of the whole plant. Overall, these results indicate that Chuannong30 has a lower Cd absorption and translocation ability than Chuanmai88, with most translocated Cd being stored in roots and leaves.\u003c/p\u003e \u003cp\u003eFurthermore, the chemical form of Cd in plants is directly related to its activity, toxicity, and migratory ability (Wang et al. \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). Notably, ethanol and dH\u003csub\u003e2\u003c/sub\u003eO Cd fractions have a higher migratory ability and toxicity than other fractions (Weng et al. \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e2012\u003c/span\u003e), as confirm in this study (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). N fertilization increased all chemical forms of Cd, except for residual Cd, which upregulated the translocation factor from the root to shoot, especially under soil Cd level of 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e; Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Increased N supply in high Cd concentrations can improve Cd absorption, accumulation and mobilization by affecting the expression of Cd-chelating N compounds (Yang et al. \u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Although no significant difference was found in concentrations of all Cd forms between cultivars and N levels at 0.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e Cd level, there was a decrease in the proportion of the residual fraction and a significant increase in all other chemical forms in soils contaminated with Cd at 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). Additionally, the ethanol fraction occupied the largest proportion of Cd in all organs in both cultivars. Moreover, the proportions of high-mobility Cd extracted by 80%ethanol and dH\u003csub\u003e2\u003c/sub\u003eO were higher in the root of Chuanmai88 than that in Chuannong30 under all the treatments, which may have contributed to the high TF\u003csub\u003eroot\u0026minus;shoot\u003c/sub\u003e value in Chuanmai88 (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), ethanol and dH\u003csub\u003e2\u003c/sub\u003eO Cd fractions represent inorganic Cd, soluble Cd salts of organic acids and dihydric phosphates and which are more contaminate to plant cells. the result implies that Chuanmai88 has more free Cd ions, which may be transported to aboveground organs.\u003c/p\u003e \u003cp\u003eAn increase in N fertilizer improves the activation of roots and organic acid secretion, reduces soil pH, increases CEC soil Cd bioavailability (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e; Liu et al. \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2015\u003c/span\u003e; Wen et al. \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Shan et al. \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e2023\u003c/span\u003e). Soil Cd bioavailability was lower in the Chuannong30 than in the Chuanmai88, especially in soils contaminated with Cd at 1.5 mg∙kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. the lower soil Cd bioavailable in the Chuannong30 could be attributed to the higher soil negative charge and pH value and lower CEC, which suppressed Cd adsorption by soil particles (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e; Hong et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2010\u003c/span\u003e; Seshadri et al. \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2017\u003c/span\u003e); Soil pH is regarded a dominating factor controlling soil Cd availability, and CEC can evaluate the Cd adsorption ability of soils. Considering that increased soil pH is beneficial to the adsorption of Cd to metal binding sites and reduces the partition of Cd to soil solution (Bai et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), the change of pH may be closely related to soil acidification, ion exchange reaction, and plant physiological processes. Consistent with previous findings (Wang et al. \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Huang et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), grain Cd content was significantly positively correlated with soil Cd bioavailability (Fig. \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). In addition, high soil Cd levels was associated with increased Cd migration ability, decreased concentration of stable form of soil Cd, and increased Cd accumulation in crops (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e), the exchangeable fraction is considered as an primary indicator for estimating the harm of Cd contaminate and observed the most significant increase. Chuanmai88 showed higher exchangeable Cd and carbonate-associated Cd than Chuannong30, and Chuannong30 seemed less sensitive to N level than Chuanmai88 under both Cd levels (Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e), indicating the cultivars with high cadmium content with the increase of soil N content promotes the activation of the cadmium migration in the soil, resulting in the accumulation of more Cd in plant.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eModerate increase in the application of N fertilizer (N\u003csub\u003e135\u003c/sub\u003e to N\u003csub\u003e180\u003c/sub\u003e) improves grain yield and regulates grain Cd content in wheat. N fertilization reduced soil pH, increased CEC and soil Cd bioavailability, upregulated Cd uptake, accumulation, and translocation, and elevated the proportion of high-mobility Cd extracted by ethanol and dH\u003csub\u003e2\u003c/sub\u003eO. Moreover, there were significant differences in Cd absorption, translocation, chemical forms, and soil Cd bioavailability between the low- and high-Cd wheat cultivars, the low-Cd cultivar had lower Cd accumulation in the grain than the high-Cd cultivar, which may be attributed to several factors, including low Cd translocation from leaf to grain, the chemical form of Cd in the cultivar, lower proportions of ethanol and dH\u003csub\u003e2\u003c/sub\u003eO Cd fractions, and lower activation of the Cd migration in the soil.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003cstrong\u003eEthics approval\u003c/strong\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent to participate\u003c/strong\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConsent for publication\u003c/strong\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eCompeting interests\u003c/strong\u003e \u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis research was funded by the Sichuan Science and Technology Program of China (2022JDRC0033, 2022ZDZX0016, 2021YFYZ0005, 2024NSFSC1223), the China Agriculture Research System (CARS-3), the National Natural Science Foundation of China (32372226, 31972960 and 32001476), and Sichuan Academy of Agricultural Sciences Program (1\u0026thinsp;+\u0026thinsp;9KJGG010, 2022ZZCX007).\u003c/p\u003e\u003ch2\u003eAuthor contribution\u003c/h2\u003e \u003cp\u003eAll authors contributed to the study conception\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e \u003cp\u003eData will be made available on reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAli H, Khan E (2018) What are heavy metals? 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Environ Pollut 340: 122792. https://doi.org/10.1016/j.envpol.2023.122792.\u003c/li\u003e\n\u003cli\u003eZhang L, Gao C, Chen C, Zhang W, Huang X, Zhao F (2020) Overexpression of rice OsHMA3 in wheat greatly decreases cadmium accumulation in wheat grains. Environ Sci Technol 54 (16): 10100\u0026ndash;10108. https://doi.org/10.1021/acs. est.0c02877.\u003c/li\u003e\n\u003cli\u003eZhen S, Shuai H, Xu C, L, G, Zhu X, Zhang Q, Zhu Q, N\u0026uacute;\u0026tilde;nez-Delgado A, CondeCid M, Zhou Y, Huang D (2021) Foliar application of Zn reduces Cd accumulation in grains of late rice by regulating the antioxidant system, enhancing Cd chelation onto cell wall of leaves, and inhibiting Cd translocation in rice. Sci Total Environ 770: 145302. https://doi.org/10.1016/j.scitotenv.2021.145302.\u003c/li\u003e\n\u003cli\u003eZhu Y, Wang Y, Zheng H, Xiang X, Wang H, Xie M, Liu H, Fang Z, Liu L, Du S (2023) N fertilizers promote abscisic acid-catabolizing bacteria to enhance heavy metal phytoremediation from metalliferous soils. Sci Total Environ 894: 164964. https://doi.org/10.1016/j.scitotenv.2023.164964.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"environmental-science-and-pollution-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"espr","sideBox":"Learn more about [Environmental Science and Pollution Research](https://www.springer.com/journal/11356)","snPcode":"11356","submissionUrl":"https://submission.nature.com/new-submission/11356/3","title":"Environmental Science and Pollution Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"cadmium, food safety, grain, heavy metals, nitrogen, wheat","lastPublishedDoi":"10.21203/rs.3.rs-5404240/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5404240/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eReasonable nitrogen (N) and low grain cadmium (Cd) accumulators can effectively reduce grain Cd content in wheat; however, the underlying mechanism remains unclear. This study aimed to investigate N affects and genotypic variation in Cd absorption, translocation and chemical forms in low (Chuannong30) and high (Chuanmai88) grain-Cd-accumulating wheat. Pot experiment was arranged in a completely randomized design consisting of two-factors: two Cd levels (low, 0.5 mg∙kg\u003csup\u003e-1\u003c/sup\u003e; high, 1.5 mg∙kg\u003csup\u003e-1\u003c/sup\u003e) and six N treatments (0, 45, 90, 135, 180, 225 kg∙ha\u003csup\u003e-1\u003c/sup\u003e). The results showed that both cultivars can be grown in low-Cd soil under N fertilization rate of 180 kg∙ha\u003csup\u003e-1\u003c/sup\u003e, without Cd toxicity issues; the low grain-Cd accumulating cultivars can be grown in high-Cd soil under fertilization rates \u0026lt; 135 kg∙ha\u003csup\u003e-1\u003c/sup\u003e, without grain toxicity. Increasing N fertilization improved Cd absorption, translocation and distribution in both cultivars, with a higher effect observed in Chuanmai88, the lower grain Cd concentrations of Chuannong30 may be attributed to low root absorption and low Cd translocation from leaf to grain. N fertilization increased all Cd chemical forms (except residual-Cd) in the root and leaf in both cultivars, especially under high soil Cd condition, Cd fractions extracted by 80% ethanol were predominant in root and leaf of both cultivars and the concentrations and proportions were also higher in Chuanmai88 than in Chuannong30. Moreover, increasing N fertilization significantly decreased soil pH, increased soil Cd exchange capacity and soil Cd bioavailability, resulting in increased Cd accumulation in plants, Chuanmai88 promoted the activation of the Cd migration in the soil.\u003c/p\u003e","manuscriptTitle":"Nitrogen affects and genotypic variation in Cd absorption, translocation and chemical forms in wheat","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-12 07:00:36","doi":"10.21203/rs.3.rs-5404240/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major Revision","date":"2024-11-28T04:51:42+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-11-19T12:04:41+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-11-14T00:35:23+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Environmental Science and Pollution Research","date":"2024-11-08T13:23:54+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-11-08T04:10:00+00:00","index":"","fulltext":""},{"type":"submitted","content":"Environmental Science and Pollution Research","date":"2024-11-06T22:10:30+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"environmental-science-and-pollution-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"espr","sideBox":"Learn more about [Environmental Science and Pollution Research](https://www.springer.com/journal/11356)","snPcode":"11356","submissionUrl":"https://submission.nature.com/new-submission/11356/3","title":"Environmental Science and Pollution Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"da3b5980-1261-49a6-8dc9-6637f8810e27","owner":[],"postedDate":"December 12th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2024-12-12T07:00:36+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-12 07:00:36","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5404240","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5404240","identity":"rs-5404240","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}