Management of Wheat Stem Rust (Puccinia graminis f.Sp. tritici) through Variety and Nitrogen Fertilizer Application rate in West Shoa Zone

Management of Wheat Stem Rust (Puccinia graminis f.Sp. tritici) through Variety and Nitrogen Fertilizer Application rate in West Shoa Zone | 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 Management of Wheat Stem Rust (Puccinia graminis f.Sp. tritici) through Variety and Nitrogen Fertilizer Application rate in West Shoa Zone Nigatu Gemechu, Alemayehu Chala, Jemal Tola, Garome Shifaraw This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7813373/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Wheat stem rust ( Puccinia graminis f.sp. tritici ) is a common fungal disease that causes significant yield reductions and grain quality deterioration. Therefore, this study was designed to investigate the efficiency of integrating different management strategies against stem rust (Sr) of wheat in the West Shoa zone during 2022/23 main growing season. A split-split plot design was used for field experiment using wheat varieties, the frequency of application of fungicides, and nitrogen fertilizer rates. The results of the field experiment revealed that a significant interaction effect of wheat variety, nitrogen fertilizer rate, and frequency of application of fungicides on disease intensity and wheat grain yield. The Wane wheat variety was found to be more resistant to stem rust, followed by Kingbird. Generally, the pressure of the disease increased with increasing nitrogen fertilizer rate from 100 to 200 kg ha − 1 . On the other hand, increasing the frequency of spraying of fungicides from 0 to 2 resulted in a lower disease pressure in all varieties. But, result is more pronounced on the susceptible wheat variety. The present findings confirmed that the role of integrated disease management may play in controlling stem rust epidemics. However, results should be verified through additional trials across agro ecologies and years. Disease progress epidemics fungicides integrated disease management rusts 1. INTRODUCTION 1.1. Back ground Wheat ( Triticum aestivum L.), with an annual global production of 772.6 million tons, is a staple food for more than 35% of the world’s population [ 1 ]. It is an important industrial and food grain, which ranks second among the most important cereal crops in the world after rice and is traded internationally [ 2 ]. It is grown from below sea level to elevations exceeding 3000 meters above sea level and at latitudes ranging from 30 ° and 60 ° N to 27 ° and 40 ° S [ 3 ]. Globally, China, India, and Russia are the largest wheat producers, while South Africa and Ethiopia are the largest wheat producers in sub-Saharan Africa (SSA) [ 4 ]. Attained average productivity is around 5 t ha- 1 with high variability between countries and regions [ 5 ]. In sub-Saharan African countries, wheat is also a strategic commodity, which generates farm income and improves the status of food security [ 6 , 7 , 8 ]. Wheat production in Ethiopia is largely carried out by small-scale farmers that rely on rainfed agriculture. Historically, Ethiopia's wheat yield oscillated between 1.1 and 1.8 t / ha for decades [ 9 ]. According to CSA [ 10 ] wheat was grown on a total area of 2.1 million hectares (1.7 million ha rainfed and 0.4 million ha irrigated) annually with a total production of 6.7 million tons of grain at an average productivity of 3.0 and 4.0 t/ha under rainfed and irrigated conditions, respectively, which is relatively less than the attainable yield of the crop. In SSA, including Ethiopia, complex and interactive effects of biotic and abiotic factors and socioeconomic challenges affect wheat production and productivity notably, in smallholder farming systems. Wheat diseases, such as stem rust caused by Puccinia graminis f.sp. tritici , stripe or yellow rust ( P . striiformis f.sp. tritici ) and leaf rust ( P . triticina ), and insect pests such as Russian wheat aphid ( Diuraphis noxia Mordvilko ) are among the critical biotic factors that affect wheat production in Ethiopia. Other major factors that contributed to low wheat yields in Ethiopia are a lack of access to improved varieties, backward agronomic practices, the use of marginal agricultural land, and terminal drought stress, among [ 11 , 12 ]. The occurrence and relative importance of those constraints vary in different agro-ecologies, and farmers may aware them differently, which affects the wheat breeding goals and hence varietal choices and adoption. It is crucial to assess individual farming systems, and farmers need to understand the prevailing factors and preferred attributes. These conditions affect the varietal choices of farmers, the design of the variety for a demand-led wheat breeding program, and the design of an effective disease control measure. Stem rust or black rust caused by ( Puccinia graminis f. sp. tritici ) is a serious wheat disease causing a decrease in wheat production in many areas of the world [ 13 ]. Stem rust occurs mainly in warm weather regions and can cause severe losses when epidemics occur [ 14 ].Rust fungi spread in the form of clonally produced dikaryotic urediospores, which can be dispersed by wind for thousands of kilometers from initial infection sites across different areas from continent to continent. Wheat rust epidemics can occur on a continental scale due to the widespread dispersal of urediospores [ 15 ]. Rust fungi are plant pathogens that pose a particularly high biosecurity threat because they can travel long distances, build up rapidly, and attack economically important plant species. The ability of rust pathogens to spread and build up rapidly also makes them extremely difficult to eradicate once introduced. Studies of rDNA sequence data have confirmed the long-held belief that P. graminis is a genetically variable complex species [ 16 , 17 ]. It comprises variants known as formae speciales (“special forms”; f. sp.), which are morphological identical but are specialized for different host species. 1.2. Statement of the Problem Wheat is among the most important staple food crops and a major diet that is consumed by more than 2.5 billion people worldwide [ 18 ]. In Ethiopia, wheat import has increased through years and in the last five years, Ethiopia imported on average 1.5 million tons of wheat at an average cost of 700 million dollars annually. The demand for wheat in Ethiopia has increased over the years due to rapid population growth and urbanization, which required a change in food preferences, which are easy and fast to prepare, such as bread, biscuits, pasta, noodles, and wheat flour porridge. This has forced Ethiopians to expand local wheat production as much as possible and look for alternatives that include changing food habits [ 19 ]. The increase in demand for wheat has presented an opportunity for greater wheat production in Ethiopia. In Ethiopia, even if the wheat area is large, the yield obtained per hectare is low compared to other countries. Low productivity is attributed to several factors, including an increase in the intensity of biotic stress (diseases and insect pests) and abiotic stress (drought and heat) and a slow rate of adoption of new agricultural technologies [ 20 ]. Therefore, understanding and prioritizing the main production constraints is crucial before embarking on the expansion of local wheat production.Despite the fact that the government started the wheat initiative in Ethiopia, the complex and interactive effects of biotic, abiotic and socioeconomic factors, particularly in smallholder farming systems, affect wheat production and productivity. Wheat stem rust caused by Puccinia graminis f.sp. tritici is among the critical biotic factors affecting wheat production in Ethiopia. Disease is a major threat to wheat production around the world [ 21 ] and can cause 100% yield losses in wide areas during epidemic years [ 22 ]. Yield loss due to stem rust in Ethiopia was estimated to reach 100% in susceptible wheat varieties at times of disease epidemics [ 23 ]. Due to its variability and diverse races, the management of rust disease has been difficult, and the disease continues to cause significant yield losses. In relation to this, there is frequent failure of resistant wheat varieties due to changes in pathogen virulence. Recurrent rust epidemics remain the main driver of the change in bread wheat varieties in Ethiopia. Massive wheat scaling projects implemented by ICARDA and CIMMYT in partnership with EIAR led to dramatic changes where old rust-prone wheat varieties such as Kubsa were replaced with newer rust-resistant wheat [ 19 ]. Varieties with a specific resistance gene usually remain effective only for a few years because the extreme selection pressure on the pathogen population with mutants results in a gain in virulence in the pathogen population for that particular gene. Due to sudden changes in stem rust race patterns, it is important to detect the resistance capacity of existing varieties. The frequent failure of resistant wheat varieties due to changes in pathogen virulence has increased the interest in chemical control of wheat rust for global food security [ 24 ]. The lack of knowledge and awareness about the nature of the disease and the inappropriate use of fungicides are also the main limitations, particularly for small-scale farmers. Farmers spray fungicides simply after they observe damaged crop, but plants may not show obvious disease symptoms until 7 to 15 days after infection. This means that after the spore is landed on the neighbor alternate host. The sprayed fungicide may protect the crop from disease for a given time, and after a time new epidemics can occur due to the repeating uredinial stage of the pathogen. Therefore, it is essential to evaluate the frequency of application of fungicides for effective and sustainable wheat rust management. Nitrogen (N) is the most important fertilizer element that determines the productivity of wheat. Previous research done on this area shows that nitrogen (N) is not only an important nutritional factor that promotes crop growth and increases crop yield but is also known to directly impact the severity of rust and powdery mildew disease [ 25 , 26 ]. Regardless of the importance and wide use of nitrogen fertilizers in wheat production, there is limited knowledge on its effect on the development of rust disease in Ethiopia. Therefore, it is important to assess the effect of nitrogen fertilizer on wheat stem rust. The current research was designed to develop an integrated wheat stem rust management strategy for the hot spot wheat production area of Ethiopia. 1.3. Specific objective To evaluate the effect of nitrogen fertilizer rates, fungicide frequencies and wheat varieties on wheat stem rust. 2. MATERIALS AND METHODS 2.1. Description of the study area The field experiment was conducted at the Ambo Agricultural Research Center (AARC) in West Shoa, Ethiopia, during the main cropping season 2022. The center was located at 08° 57'N latitude and 38° 07'E longitude, at an altitude of 2225 ma sl. The soil type is heavy clay (vertisol) with a pH of 7.8 for the most top soil (0–30 cm). The long-term total annual rain fall is 1115 mm, and the average minimum and maximum temperature are 11.7 and 25.5 o C , respectively. 2.2. Treatments, Experimental Design, and Field Management The field experiment included three varieties (Ogolcho, Kingbird, and Wane), a fungicide (Nativo R SC 300: tebuconazole 200g/l + trifloxystrobin 100g/l) in two application frequency i.e. 1 (once), and 2 (twice at 15 days interval) and three fertilizer rates (i.e. 100, 150 and 200kg nitrogen ha − 1 ). The fungicide was applied at a recommended rate of 0.75l / ha in 250 liters/ha of water using a manual knapsack sprayer. Varieties were selected based on their response to stem rust, with Ogolcho being susceptible, Kingbird moderately resistant, and Wane resistant. All varieties were seeded at the recommended rate of 150 kg seed ha − 1 and sowing date was July 5/2022. The experiment was laid out in a split-split- plot design with three replications. In the current study, fertilizer was assigned to the main plot, while fungicide frequency and varieties were assigned to the subplot and sub-subplots, respectively. This was done to minimize the risk of drifting fertilizers and fungicides. The total area of an experiment was 554m 2 (19.8m x 28m) with main plot size of 44.8m 2 (5.6m*8m) and sub-sub plot size 2.4m 2 . (1.2m x 2m). Sowing was carried out by manual drilling into 1.2 meters long of six rows with 0.2m space apart. Each plot (2.4 m 2 ) received 36g of seed. The distance between the sub-plots, main plots and blocks was 1m, 1.5m and 2m, respectively. The stem rust spreader rows (mixture of susceptible cultivars, Kubsa and Morocco) were planted perpendicular to all entries to facilitate inoculum accumulation and uniform dissemination. The TSP fertilizers were applied at the rate of 200 kg ha − 1 during planting while, UREA was applied at the knee stage of the crop before heading based on each treatment level. Weeds were controlled by hand weeding to make the wheat field free of weed. 2.3 Data Collected 2.3.1 Disease-related data To determine the response of wheat varieties to stem rust, data on disease incidence and severity were recorded on plot basis from the central four rows of the plot (1.6m 2 net area). In each plot, 10 plants were randomly selected and pre-tagged to record the severity of stem rust. The reactions of the varieties were scored 4 times in a 12 day interval starting from the onset of the disease and the associated symptoms. The incidence of stem rust was recorded as the proportion of wheat plants with symptoms and signs of stem rust. $$\:\text{D}\text{i}\text{s}\text{e}\text{a}\text{s}\text{e}\:\text{i}\text{n}\text{c}\text{i}\text{d}\text{e}\text{n}\text{c}\text{e}\:\left(\text{\%}\right)=\:\frac{\text{N}\text{u}\text{m}\text{b}\text{e}\text{r}\:\text{o}\text{f}\:\text{d}\text{i}\text{s}\text{e}\text{a}\text{s}\text{e}\text{d}\:\text{p}\text{l}\text{a}\text{n}\text{t}}{\:\text{T}\text{o}\text{t}\text{a}\text{l}\:\text{n}\text{u}\text{m}\text{b}\text{e}\text{r}\:\text{o}\text{f}\:\text{p}\text{l}\text{a}\text{n}\text{t}\:\text{a}\text{s}\text{s}\text{e}\text{s}\text{s}\text{e}\text{d}}*100$$ Disease severity was measured as a percentage of stem/leaf area covered by rust disease adopted by the modified Cobb scale (Peterson et al ., 1948). $$\:\text{D}\text{i}\text{s}\text{e}\text{a}\text{s}\text{e}\:\text{S}\text{e}\text{v}\text{e}\text{r}\text{i}\text{t}\text{y}\:\left(\text{\%}\right)=\:\frac{\text{A}\text{r}\text{e}\text{a}\:\text{o}\text{f}\:\text{s}\text{t}\text{e}\text{m}\:\text{a}\text{f}\text{f}\text{e}\text{c}\text{t}\text{e}\text{d}}{\:\text{T}\text{o}\text{t}\text{a}\text{l}\:\text{s}\text{t}\text{e}\text{m}\:\text{a}\text{r}\text{e}\text{a}\:\text{o}\text{f}\:\text{p}\text{l}\text{a}\text{n}\text{t}}*100$$ Coefficient of infection (CI) According to Saari and Wilcoxson [ 27 ], the average coefficient of infection (CI) was calculated by multiplying the constant value assigned to each type of reaction by the percentage severity. Constant values for the various reaction types varied (Table 1 ). Area under disease progress curve (AUDPC) Stem rust disease severity scores taken at different times were used to calculate the area under disease progress curve (AUPDC) of each treatment adopted from Wilcoxson et al . [ 28 ]. $$\:\text{A}\text{U}\text{D}\text{P}\text{C}={\sum\:}_{n=1}^{n-1}\:0.5\left(xi+1+xi\:\left)\right(ti+1+ti\right)$$ Where, x i =the average coefficient of infection of the ith record, Xi + 1 = the average coefficient of infection of the i + 1 record and t i + 1-ti = the number of days between the i th record and the i + 1 record, and n = number of observations. The type of reaction of wheat plants to stem rust was designated following the procedure proposed by Wilcoxson et al . [ 28 ] (Table 1 ). Table 1 Reaction type and values of the reaction type of wheat crop against wheat stem rust Reaction type Values of Reaction type Size of uredinial Resistant (R) 0.2 Small uredinial surrounded by small chlorosis or necrosis. Resistant to moderately resistant (R-MR) 0.4 Medium size uredinial surrounded by small chlorosis or necrosis. Moderately resistant (MR) 0.3 Small uredinial surrounded by medium chlorosis or necrosis. Moderately susceptible (MS) 0.8 Medium large compatible uredinial without chlorosis and necrosis Susceptible 1 Large, compatible uredinial without chlorosis and necrosis Wilcoxson et al . (1975). 2.3.2 Yield and yield related data Plant height (PH) (cm) The height of 10 randomly sampled plants from the central rows of each plot was measured from the bases of the ground to the top of the spike excluding awns and the average of the ten observations will be used for analysis. The four central rows were harvested for grain and biomass yield from each plot, leaving the border to avoid border effects. The grain moisture content was adjusted to 12%. Data were collected on: Dry matter (biomass) The total weight of the above ground part including the grain. Thousand seeds weight (TSW) The weight of 1000 seeds was determined by carefully counting the grains; and weighing them using a sensitive balance. Grain Yield (GY/ha) The weight of all the kernels after harvesting was measured in grams per plot and converted into kg/ha for analysis. 2.4. Data Analysis The incidence, severity and AUDPC data from the disease were subjected to analysis of variance (ANOVA) using the R software package version 4.1.0. Least Significant Difference (LSD) at the 0.05 probability level was used for mean separation. 3. RESULT AND DISCUSSION 3.2.1. Final severity of stem rust There were significant differences (p < 0.01) differences in the final values of the rust stem rust severity (FRS) between the N rates, the varieties, and the frequencies of application of fungicides(Appendix Table 1). The highest final severity of stem rust of 77% was scored in the susceptible variety (Ogolcho) with 200 kg/ha of N fertilizer and no application of fungicide. The FRS was significantly reduced (to up to 0%) as a result of the application of the fungicide once and twice (tebuconazole 200g/lt + tryfloxystrobin 100g/l), across varieties and nitrogen fertilizer rates. An FRS of 52% was scored on the same variety (Ogolcho) with a fertilizer rate of 150kg / ha of N without fungicide protection. In plots that did not receive fungicide application, the lowest FRS (11.6%) was recorded in the Kingbird variety with 100kg N/ha (Table 2 ). The application of the fungicide did not cause significant variation in FRS in the moderately resistant Kingbird variety. Also, this variety reacted more or less the same or even better, in some cases, compared to the Wane variety, which is considered resistant to wheat stem rust. The current results suggest a differential response of wheat varieties to stem rust according to the rate of N fertilizer application and the frequencies of fungicide application. The present results were in agreement with the findings of previous work by several scholars who reported that the rate of disease progress depends on the resistance level of the host used during the growing period and the supplemented management options [ 29 , 30 ]. In the present work, varieties receiving 100 or 150 Kg N / ha together with a once or twice fungicide application had significantly lower FRS compared to 200KgN/ha and no fungicide application. The higher FRS in wheat varieties as a result of the highest N rate (200 kg / ha) could be linked to increased susceptibility as a result of plants becoming more succulent. Stakman and Aamodt [ 31 ] also concluded that the wall of plant fertilized with excess nitrogen is thinner than they normally would be and parasitic fungi therefore can penetrate more easily. Rust severity may be further increased by excessive nitrogen fertilization resulting in denser stands and delayed maturity [ 32 ]. In the same manner, wheat overfertilized with nitrogen especially when there was insufficient supply of potash or phosphorus, also nearly always was severely rusted. Stakman and Aamodt [ 31 ] have also demonstrated the effect of fertilizer on wheat infection by P. graminis . Similarly, wheat grown on an insufficiently fertilized soil could also suffer the greatest damage from stem rust. Therefore, the balance of soil nutrients is very important to improve wheat productivity, especially in areas of high disease pressure. Table 2 Effect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on final rust severity and coefficient of infection of wheat stem rust Final rust severity Coefficient of infection Nitrogen kg/ha Variety Fungicide Frequency Fungicide Frequency 0 Once Twice 0 Once Twice 200 Ogolcho 76.7 a 5 jk 5 jk 76.7 a 2 ij 5 ghi Kingbird 23.3 e 4 jk 0 l 16 d 1.6 ij 0 j Wane 33.3 c 10 hl 1.7 kl 13.3 de 10 ef 07 j 150 Ogolcho 51.67 b 6.67 ij 1.67 lk 51.67 b 6.66 ghi 1.7 ij Kingbird 13.3 gh 4j k 0 l 7.33 fgh 0.73 l 0 l Wane 18.3 f 5 jk 0 l 8.67 fg 2.67 jkl 0 l 100 Ogolcho 28.33 d 2.3 kl 1.7 kl 26.7 c 1.2 ij 0 j Kingbird 11.67 j 4 jk 0 l 4.7 hi 3.5 hij 0 j Wane 16.67 fg 5 jk 0 l 6.7 fgh 1.7 ij 0 j CV (%) 19.1 24.9 LSD (0.05) 3.8 3.8 LSD 0.05 = List of significant differences at%, CV = Coefficient of variation. Means with the same letter are not significantly different for each variable. Consistent with this study, Tadesse et al . [ 30 ]; Wubishet and Tamene [ 33 ] and Foster et al. [ 34 ] found that the integration of variety and fungicide application reduced disease levels and increased crop yield attributes. Phillip and Nathan [ 35 ] also noted similar results on wheat diseases that fungicide significantly reduced disease severity and increased yield parameters over the unsprayed plots. 3.2.2. Coefficient of infection The infection coefficient (CI) was significantly (p < 0.01 ) affected by the treatment combinations (Appendix Table 1). In general, CI of the stem rust in wheat varieties varied with the increase in the rate of fertilizer N and the decrease in the frequency of application of fungicides. Wheat plots that received the highest nitrogen fertilizer without fungicide spray had higher CI values that reached up to 76.7 in the susceptible variety (Ogolcho) (Table 2 ). In line with this, a significant effect of nitrogen fertilizer rate on CI was also evidenced by the study of Ali et al. [ 36 ]. 3.2.3. Area under stem rust progress curve Analysis of variance indicated that the interaction of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties showed significant differences (p < 0.01) in the area under the stem rust progress curve and the relative area under the stem rust progress curve (Appendix Table 1).The AUDPC values ranged from 5.3% days in the resistant variety (Wane) with 100kg N/ha on plot without fungicide to 1250% in days in the susceptible variety (Ogolcho) (200 kg N / ha) without fungicide while the moderately resistant Kingbird variety had intermediate AUDPC values of stem rust. In general, the AUDPC values of stem rust increased with increasing N fertilization rate and decreasing application of fungicides. As stated by Van der Planck [ 37 ], the disease progress curve was a better indicator of disease expression over time. Therefore, the selection of cultivars with lower AUDPC values is acceptable for practical purposes. In the present study, nitrogen fertilizer rate and fungicide frequency lacked consistently significant influence on moderately resistant variety (Kingbird) and resistant variety (Wane). In contrast, the susceptibility of the Ogolcho variety increased with the application of nitrogen fertilizer. Current results were in line with those of Viljanen-Rollinson et al . [ 38 ], who reported that the more resistant cultivars had very low AUDPCs and would probably not benefit from an application of fungicide to control wheat rust, unless the pathotypes present were highly virulent against these cultivars. The results obtained in the current work were also in agreement with the findings of Haggag et al. [ 39 ] that confirmed the effect of nitrogen fertilizer on susceptible variety. Phillip and Nathan [ 35 ] reported that the highest value of AUDPC for yellow and stem rust was due to the highest disease development in plots that did not spray with any combinations of crop varieties and fungicide applications; the moderately resistant varieties had the lowest AUDPC for yellow and stem rust diseases when supplemented with fungicide application. The work of Fleitas et al. [ 40 ] also revealed that plants that receive high N fertilization are more susceptible to leaf rust. However, the current findings contradicted the results of Stakman and Aamodt [ 31 ], who reported no fundamental changes in the degree of physiological resistance to stem rust when plants were supplied with nitrogen fertilizer. The less frequent sprays allowed the development of multiple levels of epidemics and were not effective in controlling the disease in Ogolcho, as the severity of stem rust is very high in this variety. These results reiterate the role of varietal resistance in determining the frequency and effectiveness of chemical sprays once rust has been established. Regarding the effect of fungicides, it has been reported that fungicides reduced subsequent disease progress on plant parts that were slightly infected at the time of fungicide application, but were not effective on plant parts that were heavily infected. Therefore, rust control strategy through fungicides must consider the time of onset, early detection of the disease, and early application of fungicides if economic control of the disease is intended [ 41 ]. 3.2.4. Relative area under stem rust progress curve The highest rAUDPC of 172.3, 88.2, 39.5 were recorded in unsprayed plots of the susceptible variety (Ogolcho) at nitrogen fertilizer levels of 200, 150, 100 kg / ha, respectively (Table 3 ). The significant effect of nitrogen fertilizer on rAUDPC was observed in only susceptible varieties, while the other two varieties showed significantly lower rAUDPC regardless of the N rate. Table 3 Effect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on area under stem rust progress curve and relative area under stem rust progress curve AUDPC rAUDPC Nitrogen kg/ha Variety Fungicide Frequency Fungicide Frequency 0 Once Twice 0 Once Twice 200 Ogolcho 1250a 277.9 c 231.3 cd 172.3 a 38.3 c 31.9 cd Kingbird 74.7 ef 69.1 ef 51.1 ef 10.3 f 9.5 f 7 ef Wane 68 ef 53 ef 30.1 ef 9.4 ef 7.3 ef 4.2 ef 150 Ogolcho 640 b 322.5 d 183.3 c 88.2 b 81.1 bc 25.3 d Kingbird 57.3 ef 22.3 ef 23.9 ef 7.9 ef 3.1 ef 3.3 ef Wane 91.3 e 20.7 ef 5.5 f 12.6 e 2.8 ef 0.8 f 100 Ogolcho 286.5 c 179.7 d 171.3 d 39.5 c 24.8 d 23.6 d Kingbird 37.3 ef 14.7 f 16.1 ef 5.1 ef 2 f 2.2 ef Wane 38.7 ef 18. ef 5.3 f 5.3 ef 2.5 ef 0.7 f CV (%) 27.4 27.4 LSD (0.05) 75.6 10.4 LSD 0.05 = List of significant differences in%, CV = Coefficient of variation, AUDPC = Area under disease progress curve, rAUDPC = relative area under disease progress curve. Means with the same letter are not significantly different for each variable. 3.3. Yield and yield related parameters 3.3.1. Plant Height and Biomass There was a significant difference (p < 0.05) in plant height between tested varieties, fertilizer rate, and frequency of application of fungicides (Appendix Table 2). The height of the plant ranged from 68.4 cm in the unsprayed Wane variety treated with 100kg/ha of nitrogen fertilizer to 96.6 cm in the Ogolcho variety treated with 200kg/ha of N fertilizer sprayed twice with Nativo R SC 300. The Kingbird variety had an intermediate plant height that was not significantly affected by the nitrogen fertilizer rate. The application of fungicides had a significant effect on the height of the susceptible wheat variety (Ogolcho), while no such effect was observed in the resistant (Wane) and moderately resistant (Kingbird) varieties (Table 4 ).There was a significant difference in dry biomass due to nitrogen level and variety, but the results were not consistent. Ogolcho and Kingbird recorded a higher biomass yield than Wane on sprayed plots with higher nitrogen fertilizer rates. A significant effect of the fungicide on the biomass of the plant was evident on the susceptible variety (Ogolcho). The highest biomass (11666.7 kg/ha) for Ogolcho variety was recorded from sprayed plots once and twice with higher fertilizer rates (Table 4 ). Table 4 Effect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on plant height and biomass yield under wheat stem rust epidemics Plant height (cm) Biomass yield (kg/ha) Nitrogen kg/ha Variety Fungicide Frequency Fungicide Frequency 0 Once Twice 0 Once Twice 200 Ogolcho 91.5 b 92.8 ab 96.6 a 10937.5 bc 11666.6 a 11666.6 a Kingbird 83.4 d − g 80.6 e − h 81.3 d − h 10937 a − c 11354 ab 10312 a − d Wane 79.6 gh 79 gh 80.1 f − h 9583.3 c − f 9791.6 c − f 9583.3 c − f 150 Ogolcho 89.8 bc 91.9 ab 93.2 ab 9687.5 c − f 10416 a − d 10104 b − e Kingbird 81.6 d − h 81 d − h 79.5 gh 10104 b − e 10625 a − c 10000 b − e Wane 81 d − h 83 d − g 79.5 gh 9166.6 d − g 8750 e − h 8750 e − h 100 Ogolcho 85 c − f 85.8 cd 85.7 c − e 8125 g − i 7708.3 h − j 8437.5 f − i Kingbird 82 d − h 82 d − h 77.3 hi 7083.3 i − k 7083.3 i − k 7916.6 g − j Wane 68.4 j 72.6 ij 73 ij 6666.6 jk 7291.6 ij 5833.3 k CV (%) 5.2 9 LSD (0.05) 3.8 1384.1 LSD 0.05 = List of significant different at %, CV = Coefficient of variation, PH = Plant height, BM = biomass. Means with the same letter are not significantly different for each variable. 3.3.2. Grain yield Wheat grain yield differed by nitrogen rate, fungicide application frequency and wheat varieties, although the results were not consistently significant (Appendix Table 2). The highest grain yield of 3627 kg/ha was obtained from the resistant variety Wane) with two fungicide sprays and the highest N fertilization rate (200kg/ha). On the other hand, the lowest wheat grain yield of 1393kg/ha was recorded from the Kingbird variety without fungicide spray and 100kgN/ha. Generally, wheat grain yield increased with fungicide sprays and N fertilization rate. But the difference in yield was not significant in many instances except between 100 and 200kgN/ha (Table 5 ). Table 5 Effect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on TSW and wheat yield under wheat stem rust epidemics Yield (kg/ha) Thousand seed weight (g) Nitrogen kg/ha Variety Fungicide Frequency Fungicide Frequency 0 Once Twice 0 Once Twice 200 Ogolcho 3271 cd 3610 ab 3624.2 a 38 f−i 44 a−d 46 ab Kingbird 2579 g−i 2723 f−h 2945 ef 38.7 f−i 37.1 g−j 37 g−j Wane 3320 bc 3515 a − c 3627 a 41 c−f 42.5 b−e 43 b−d 150 Ogolcho 3275 cd 3477 abc 3589 ab 41 d−g 44.2 a−d 47.3 a Kingbird 2479 g − i 2417.8 ij 2637 g − i 37 h−k 35 i − k 36.1 . 3 Wane 2553 g − i 2928.9 ef 3015 de 39.2 e−h 42.1 b−f 44.6 a−c 100 Ogolcho 2453 h − j 2676 f − i 2765 e−g 40.7 d−g 44.0 a−d 44.1 a−d Kingbird 1393 l 1859.3 k 1752 k 33.9 j−l 31.1 l 33 kl Wane 2174. 1j 2400.1 i 1752 k 39 e − h 41.5 c−f 42.5 b−e CV (%) 6.3 5.5 LSD (0.05) 290.7 3.7 LSD 0.05 = List of significant differences at%, CV = Coefficient of variation. Means with the same letter are not significantly different for each variable. The application of fungicides once to twice was effective in obtaining higher yields. Estimating yield loss by a disease is a prerequisite to develop strategies for disease control particularity through breeding objectives for disease resistance [ 42 ]. 3.3.3. Thousand Seed weight Analysis of variance revealed the significant effect (p < 0.01 ) of nitrogen rate, frequency of application of fungicides and wheat varieties on thousand seed weights (Appendix Table 2). Treatments with a two-time fungicide spray frequency had significantly higher thousand seed weights than once sprayed and untreated plots. The highest thousand seed weight of 47.3 g was recorded in the susceptible variety (Ogolcho) with two fungicide sprays and 150kgN/ha. On the other hand, the lowest thousand seed weight of 31g was recorded from the moderately resistant variety (Kingbird) with one fungicide spray and 100kgN/ha. Thousand seed weights (TSW) in untreated plots of highly N fertilizer rate plots ranged from 38g in susceptible variety (Ogolcho) to 41g in resistant variety (Wane). The TSW of the twice treated plot with highly fertilized plots ranged from 37 g in the moderately resistant variety (Kingbird) to 46 g and in the susceptible variety (Ogolcho). On the other hand, unsprayed plots fertilized with 150kgN/ha had a thousand seed weights of 37 on the moderately resistant variety and 41g and on the susceptible variety (Ogolcho) (Table 5 ). Regarding the frequency of fungicide spray, TSW in two sprayed plots varied from 33 g for the moderately resistant variety with 100kgN/ha to 47.3 g for the susceptible variety with 150kgN/ha. The susceptible variety Ogolcho sprayed once and twice with Nativo and treated with 200kg/ha had a better thousand seed weight and has a relatively equal grain yield with the resistant variety. Nzuve et al . [ 43 ] reported that stem rust significantly reduces TKW in wheat. He also indicated that the significant effect of stem rust on TKW is brought about by its effect on photosynthesis and subsequent grain filling. According to [ 44 , 45 , 46 ], the competition of rust fungi for photosynthates in grain filling would have increased importance in reducing the number and size of seeds in plants. In this study, no protected check plot was established for each treatment to obtain information to calculate yield loss. 4. CONCLUSION Wheat is one of the most important crops in Ethiopia and around the world. However, the crop is affected by abiotic and biotic constraints, of which stem rust caused by P. graminis f.sp. tritici is one. The results of the current field experiment revealed a significant effect of the variety of wheat, the rate of N fertilizer and the frequency of fungicides on the development of wheat stem rust, the yield and related parameters of wheat. Regardless of fungicide applications, stem rust was less severe in moderately resistant varieties (Kingbird) and resistant varieties (Wane) compared to susceptible varieties (Ogolcho). The less severe disease was mainly due to the inherent nature of the varieties to resist rust epidemics, although the weather conditions at the experiment site appeared to be conducive to the development of the disease. Similarly, current results demonstrated that stem rust epidemics were different at the three N fertilizer rates (ie 100, 150 and 200 kg/ha). High stem rust intensity was observed in unsprayed plots with a high nitrogen fertilizer rate and this may be due to the effect of N on disease through changes in canopy microclimate caused by increased canopy size. The unsprayed plots exhibited higher disease intensity rates, while twice the application of Nativo R SC 300 fungicides (tebuconazole 200g/lt + tryfloxystrobin 100g / l) ensured better control of the development of stem rust. The integrated management of stem rust through nitrogen fertilizer rate, wheat varieties and fungicide spray frequency was highly associated with disease parameters, yield and yield components. The wane had the highest yielder (3,627 kg / ha) supplemented with a higher N fertilizer rate (200kg/ha) and twice the fungicide spray. The Ogolcho variety resulted in the highest TSW (47g) when supplemented with an intermidate N fertilizer level and twice the application of fungicide.Variation in the genetic background of the varieties, nitrogen level, and frequency of fungicide applications could have resulted in differences in GY and TKW in this study. Based on the response to yield of the wheat varieties tested in the current experiment, the varieties performed best when treated with 200 N fertilizer applied with a twice the frequency of the fungicide (tebuconazole 200g/lt + tryfloxystrobin 100g/l) at a 15-day interval. On the basis of the results, the following recommendations are made: Further studies should be conducted on host resistance, fungicide application frequencies, and nitrogen fertilizer rate in multiple locations, years, and hot spot agro ecologies to stem rust to manage disease in a sustainable manner. There must also be a plan to establish integrated management of wheat stem rust. A preprint of this article has been published by Gemechu et al . (47) with https://www.researchsquare.com/article/rs-4293041/v1 Declarations Ethics Consent to participate Not applicable Ethics approval and consent to participate Consent for publication Not applicable Competing interests The authors declare there was no competing of interests. Clinical trial Not applicable Funding This work did not receive any fund. Author Contribution Conceptualization: Nigatu GemechuFormal analysis: Nigatu Gemechu & Garome ShifarawInvestigation: Nigatu GemechuMethodology: Nigatu GemechuSoftware: Garome Shifaraw & Nigatu GemechuSupervision: Alemayehu Chala & Jemal TolaValidation: Alemayehu Chala & Jemal TolaWriting – original draft: Nigatu GemechuWriting – review & editing: Garome Shifaraw, Alemayehu Chala & Jemal Tola Data Availability All data generated or analyzed during the study are included in this manuscript. References Statista. (2021). Worldwide mobile education app downloads from 1st quarter 2017 to 1st quarter 2020, by platform. Retrieved from https://www.statista.com/statistics/1128262/mobile-education-app-downloads worldwide-platfor ms-millions/. Falola A, Achem BA, Oloyede WO, Olawuyi GO. Determinants of commercial production of wheat in Nigeria: A case study of Bakura Local Government Area, Zamfara State. Trakia J Sci. 2017;1:15–4. Nuttonson MY. 1957. Wheat-climatic relationships and the use of phenology in ascertaining the thermal and photo-thermal requirements of wheat. USDA. 2019. USDA world markets and Trade Report. Accessed on December 15, 2019.Vanderplank J., 1963. Plant Diseases: epidemics and control. Academic Press, New York. Zegeye F, Alamirew B, Tolossa D. Analysis of wheat yield gap and variability in Ethiopia. Int J Agricultural Econ. 2020;4:89–98. Negassa A, Shiferaw B, Koo J, Sonder K, Smale M, Braun H, Gbegbelegbe S, ZheGuo D, Wood S, Payne T, Abeyo B. 2013. The potential for wheat production in Africa. Minot N, Warner J, Lemma S, Kasa L, Gashaw A, Rashid S. The wheat supply chain in Ethiopia: Patterns, trends, and policy options. Gates Open Research. 2019;3(174):174. Amentae TK, Hamo TK, Gebresenbet G, Ljungberg D. Exploring wheat value chain focusing on market performance, post-harvest loss, and supply chain management in Ethiopia: The case of Arsi to Finfinnee market chain. J Agric Sci. 2017;9(8):22. FAO. 2021. Food and Agricultural Organization of the United Nations (FAO): FAO Global Statistical Year book. http://www.fao.org/faostat/en/#data/QC . Meta data last certified Nov. 2017. CSA. 2022. Agricultural sample survey of area and production of major crops. Available from: https://www.statsethiopia.gov.et/ . Accessed 2022 Jul 15. Netsanat B, Shimelis H, Laing M. Appraisal of farmer’s wheat production constraints and breeding priorities in rust prone agro-ecologies of Ethiopia. Afr J Agric Res. 2017;12:944–52. Semahegn Y, Shimelis H, Laing M, Mathew I. Farmers’ preferred traits and perceived production constraints of bread wheat under drought-prone agro-ecologies of Ethiopia. Agric Food Secur. 2021;10:18. Roelfs AP. Estimated losses caused by rust in small grain cereals in the United States, 1918- . Volume 76. (Vol. 1356). Department of Agriculture, Agricultural Research Service; 1978. Leonard KJ, Szabo LJ. Pathogen profile: Stem rust of small grains and grasses caused by Pucciniagraminis . Mol Plant Pathol. 2005;6:99–111. Khan MH, Bukhari A, Dar ZA, Rizvi SM. 2013. Status and strategies in breeding for rust resistance in wheat. Zambino P, Szabo L. Phylogenetic relationships of selected cereal and grass rusts based on rDNA sequence analysis. Mycologia. 1993;85:401–14. Abbasi M, Goodwin S, Scholler M. Taxonomy, phylogeny, and distribution of Puccinia graminis, the black stem rust: new insights based on rDNA sequence data. Mycoscience. 2005;46:241–7. Bentley AR, Donovan J, Sonder K, Baudron F, Lewis JM, Voss R, Rutsaert P, Poole N, Kamoun S, Saunders DGO, Hodson D, Hughes DP, Negra C, Ibba MI, Snapp S, Sida TS, Jaleta M, Tesfaye K, Becker-Reshef I, Govaerts B. Near- to long-term measures to stabilize global wheat supplies and food security. Nat Food. 2022;1–4. https://doi.org/10.1038/s43016-022-00559- y . Wuletaw T, Wondwosen SH, Tafesse S, Zewdie B. 2022. Wheat Production and Breeding in Ethiopia: Retrospect and Prospects. Netsanet B, Getaneh W, Tsegab T, Berhanu B, Nigussie H. 2020. Survey and surveillance of wheat rusts in the major wheat growing areas of Ethiopia during 2017–2019.Pp 13–19. In D. Eshetu & G. Bedada, editors, Proceedings on the delivering genetic gain in wheat (DGGW) project closing workshop 120p. Ethiopian Institute of Agricultural Research. Kanti K, Rawal C, Rajdeep HD, Devanna JBN. Draft Genome of the Wheat Rust Pathogen ( Puccinia triticina ) Unravels Genome-Wide Structural Variations during Evolution. Genome Biology Evolution; 2016. Park RF. Stem rust of wheat in Australia. Australian J Agric Res. 2007;58:558–66. Bechere E, Kebede H, Belay G. Durum wheat in Ethiopia: An old crop in an ancient land. Institute of Biodiversity Conservation and Research (IBCR); 2000. p. 68. Rowell J. Chemical control of the cereal rusts. Annual Rev Phytopathol. 1968;6:243–62. Chen Y, Zhang F, Tang L, Zheng Y, Li Y, Christie P, Li L. Wheat powdery mildew and foliar N concentrations as influenced by N fertilization and belowground interactions with intercropped faba bean. Plant Soil. 2007;291:1–13. Devadas R, Simpfendorfer S, Backhouse D, Lamb DW. Effect of stripe rust on the yield response of wheat to nitrogen. Crop Journa. 2014;1 2:201–6. Saari E, Wilcoxson R. Plant disease situation of high yielding durum wheat in Asia and Africa. Annu Rev Phytopathol. 1974;2:49–68. Wilcoxson RD, Skovmand B, Atif AH. Evaluation of wheat cultivars ability to retard development of stem rust. Annual Appl Biology. 1975;80:275–81. Mercer PC, Ruddock A. Disease management of winter wheat with reduced doses of fungicides in Northern Ireland. Crop Prot. 2005;24:221–8. Tadesse W, Bishaw Z, Assefa S. Wheat production and breeding in sub-Saharan Africa: Challenges and opportunities in the face of climate change. Int J Clim Change Strateg Manag. 2019;11:696–715. Stakman EC, Aamodt OS. The effect of fertilizers on the development of stem rust of wheat. Journal Agricultural Research. 1924;27:341–79. Knott DR, Knott DR. 1989. Genetic analysis of resistance. Wheat Rusts—Breeding Resist pp.58–83. Wuletaw T, Wondwosen SH, Tafesse S, Zewdie B. 2022. Wheat Production and Breeding in Ethiopia: Retrospect and Prospects. Foster AJ, Lollato R, Vandeveer M, De Wolf ED. Value of Fungicide Application in Wheat Production in Southwest Kansas. Kans Agricultural Exp Stn Research Reports. 2017;3:5–8. Phillip NS, Nathan M. Evaluation of foliar fungicide programs in mid-Atlantic winter wheat production systems. Crop Prot. 2018;13:103–10. Ali S, Shah SJA, Raman IKH, Maqbool K, Ullah W. Partial resistance to yellow rust in introduced winter wheat germplasm at the north of Pakistan. Aust J Crop Sci. 2009;3(1):37. Van der Plank JE. 1963. Plant Diseases Epidemics and Control. New York & London. Viljanen-Rollinson SLH, Armour T, Cromey MG. Fungicide control of strip rust in wheat: Protection or eradication. New Z plant Prot. 2002;55:336–40. Haggag ME, Eweida MH, El-Sayed FF. The effect of nitrogen application on the development of rusts on wheat varieties. Acta Mycologica. 1976;12(2):191–4. Fleitas MC, Schierenbeck M, Gerard GS, Dietz JI, Golik SI, Campos PE, Simón MR. How leaf rust disease and its control with fungicides affect dough properties, gluten quality and loaf volume under different N rates in wheat. J Cereal Sci. 2018;80:119–27. Beard C, Jayasena K, Thomas G, Loughman R. Managing Stem Rust of Wheat. Plant Pathology, Department of Agriculture, Western Australia; 2004. Simmonds NW. 1988. Synthesis the strategy of rust resistance breeding N. W. Simmonds and S. Rajaram, editors, Breeding Strategies for Resistance to the Rusts of wheat. CIMMYT, Mexico. 119–136 P. Nzuve FM, Bhavani S, Tusiime G, Njau P, Wanyera R. 2012. Evaluation of bread wheat for both seedling and adult plant resistance to stem rust. African Journal of Plant Science 6:426– 432. Agrios GN. Plant Pathology. New York: Academic; 1988. Nigus M, Shimelis H, Mathew I, Abady S. Wheat production in the highlands of Eastern Ethiopia: opportunities, challenges and coping strategies of rust diseases. Acta Agriculturae Scand Sect B—Soil Plant Sci. 2022;72(1):563–75. Mengesha GG. 2020. Management of yellow rust (Puccinia striiformis f. sp. tritici) and stem rust (Puccinia graminis f. sp tritici) of bread wheat through host resistance and fungicide application in Southern Ethiopia. Cogent Food & Agriculture , 6 (1), p.1739493. Gemechu N, Chala A, Tola J, Shifaraw G. 2024. Management of wheat stem rut (Puccinia graminis f. Sp. Tritici) through variety and nitrogen fertilizer application rate in the west Shoazone. https://www.researchgate.net/publication/380121404_Management_of_wheat_stem_rut_Puccinia_graminis_fSp_Tritici_through_variety_and_nitrogen_fertilizer_application_rate_in_the_west_Shoa_zone Additional Declarations No competing interests reported. Supplementary Files AppendixTable.docx Cite Share Download PDF Status: Posted Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-7813373","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":560592172,"identity":"dfbb3761-ad1e-42d6-a3fd-61024b37e9a4","order_by":0,"name":"Nigatu Gemechu","email":"","orcid":"","institution":"Mattu University Bedele Campus","correspondingAuthor":false,"prefix":"","firstName":"Nigatu","middleName":"","lastName":"Gemechu","suffix":""},{"id":560592173,"identity":"90256edd-2d4a-470b-bd10-4d8441c8f7d5","order_by":1,"name":"Alemayehu Chala","email":"","orcid":"","institution":"Hawassa university, College of Agriculture","correspondingAuthor":false,"prefix":"","firstName":"Alemayehu","middleName":"","lastName":"Chala","suffix":""},{"id":560592174,"identity":"93fda2ac-7e84-4422-9c09-66f1d86aa9e3","order_by":2,"name":"Jemal Tola","email":"","orcid":"","institution":"Ethiopian Institute of Agricultural Research, Ambo Agricultural Research Center","correspondingAuthor":false,"prefix":"","firstName":"Jemal","middleName":"","lastName":"Tola","suffix":""},{"id":560592175,"identity":"f7d66a01-82f1-42ad-8522-aa0c56d51c0a","order_by":3,"name":"Garome Shifaraw","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBklEQVRIiWNgGAWjYDACCcaGD0hcGyBmbDxAQEvjDCRuGkhLAwEtDIzIWg6DSbxa5Gc3Nzb83GOXON/97MNHNyrO261tPwy0pcYmGpcWgzsHGxt7niUnbjyTbmycc+Z28rYziUAtx9JyG3BpkUhsf8BzgDl3Y0Mam3Ru2+1kswNALYwNh3FqkZ+R2Nj450B97sb+Z0At/84lm51/iF8Lw43ExmaeA4dz50uAbGk4YGd2g4AtBiAtMgeO12+QeMZsnHMsOcHsBtCWBDx+kZ+R/rDxzYFqY/n+NMbHOTV29mbn0x8++FBjg9thcOsOQOhEsMoEQsrB1kENtSdG8SgYBaNgFIwsAAB/22wY+NmEegAAAABJRU5ErkJggg==","orcid":"","institution":"Mattu University Bedele Campus","correspondingAuthor":true,"prefix":"","firstName":"Garome","middleName":"","lastName":"Shifaraw","suffix":""}],"badges":[],"createdAt":"2025-10-09 05:53:27","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7813373/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7813373/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":98535705,"identity":"768722cf-cd27-44db-996f-197bd33f3106","added_by":"auto","created_at":"2025-12-18 16:45:30","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":70381,"visible":true,"origin":"","legend":"","description":"","filename":"NDfoodV41.docx","url":"https://assets-eu.researchsquare.com/files/rs-7813373/v1/aaea2ec7606ecc0c4e469089.docx"},{"id":98626431,"identity":"6327bd89-6a5f-40e2-99b7-d9f112f829f6","added_by":"auto","created_at":"2025-12-19 17:09:44","extension":"json","order_by":1,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":5807,"visible":true,"origin":"","legend":"","description":"","filename":"49f6d0844f1641dca8c8743c9f8abd54.json","url":"https://assets-eu.researchsquare.com/files/rs-7813373/v1/ada5e6d5f08d4823bb489864.json"},{"id":98535708,"identity":"63a439ea-843f-4140-863d-6f43e01ca6b8","added_by":"auto","created_at":"2025-12-18 16:45:31","extension":"xml","order_by":2,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":154839,"visible":true,"origin":"","legend":"","description":"","filename":"49f6d0844f1641dca8c8743c9f8abd541enriched.xml","url":"https://assets-eu.researchsquare.com/files/rs-7813373/v1/4220aedd62c489c783a4f978.xml"},{"id":98535707,"identity":"807c1774-a42d-4fe2-8504-ce094773e108","added_by":"auto","created_at":"2025-12-18 16:45:30","extension":"xml","order_by":3,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":153510,"visible":true,"origin":"","legend":"","description":"","filename":"49f6d0844f1641dca8c8743c9f8abd541structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7813373/v1/b5f7a49b234b3affbb91f519.xml"},{"id":98535709,"identity":"b6d5fecf-4916-433b-b5d3-759525bf78c7","added_by":"auto","created_at":"2025-12-18 16:45:31","extension":"html","order_by":4,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":161754,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7813373/v1/e4ff9cd72daae44821e4df34.html"},{"id":104781662,"identity":"98b966b9-4a57-4f43-a566-b269066f87e7","added_by":"auto","created_at":"2026-03-17 07:56:06","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1138806,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7813373/v1/5205fcc2-2771-43a9-814c-e769f9cf5cff.pdf"},{"id":98535704,"identity":"e043f6e2-2e1f-428b-a03f-8bfaf8d2c040","added_by":"auto","created_at":"2025-12-18 16:45:30","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":20600,"visible":true,"origin":"","legend":"","description":"","filename":"AppendixTable.docx","url":"https://assets-eu.researchsquare.com/files/rs-7813373/v1/23a86b5004bd0b96324c653a.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Management of Wheat Stem Rust (Puccinia graminis f.Sp. tritici) through Variety and Nitrogen Fertilizer Application rate in West Shoa Zone","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cdiv id=\"Sec2\" class=\"Section2\"\u003e \u003ch2\u003e1.1. Back ground\u003c/h2\u003e \u003cp\u003eWheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.), with an annual global production of 772.6\u0026nbsp;million tons, is a staple food for more than 35% of the world\u0026rsquo;s population [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. It is an important industrial and food grain, which ranks second among the most important cereal crops in the world after rice and is traded internationally [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. It is grown from below sea level to elevations exceeding 3000 meters above sea level and at latitudes ranging from 30 \u0026deg; and 60 \u0026deg; N to 27 \u0026deg; and 40 \u0026deg; S [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Globally, China, India, and Russia are the largest wheat producers, while South Africa and Ethiopia are the largest wheat producers in sub-Saharan Africa (SSA) [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Attained average productivity is around 5 t ha-\u003csup\u003e1\u003c/sup\u003e with high variability between countries and regions [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. In sub-Saharan African countries, wheat is also a strategic commodity, which generates farm income and improves the status of food security [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWheat production in Ethiopia is largely carried out by small-scale farmers that rely on rainfed agriculture. Historically, Ethiopia's wheat yield oscillated between 1.1 and 1.8 t / ha for decades [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. According to CSA [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e] wheat was grown on a total area of 2.1\u0026nbsp;million hectares (1.7\u0026nbsp;million ha rainfed and 0.4\u0026nbsp;million ha irrigated) annually with a total production of 6.7\u0026nbsp;million tons of grain at an average productivity of 3.0 and 4.0 t/ha under rainfed and irrigated conditions, respectively, which is relatively less than the attainable yield of the crop. In SSA, including Ethiopia, complex and interactive effects of biotic and abiotic factors and socioeconomic challenges affect wheat production and productivity notably, in smallholder farming systems. Wheat diseases, such as stem rust caused by \u003cem\u003ePuccinia graminis\u003c/em\u003e f.sp. \u003cem\u003etritici\u003c/em\u003e, stripe or yellow rust (\u003cem\u003eP\u003c/em\u003e. \u003cem\u003estriiformis\u003c/em\u003e f.sp. \u003cem\u003etritici\u003c/em\u003e) and leaf rust (\u003cem\u003eP\u003c/em\u003e. \u003cem\u003etriticina\u003c/em\u003e ), and insect pests such as Russian wheat aphid (\u003cem\u003eDiuraphis noxia\u003c/em\u003e Mordvilko\u003cem\u003e)\u003c/em\u003e are among the critical biotic factors that affect wheat production in Ethiopia. Other major factors that contributed to low wheat yields in Ethiopia are a lack of access to improved varieties, backward agronomic practices, the use of marginal agricultural land, and terminal drought stress, among [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The occurrence and relative importance of those constraints vary in different agro-ecologies, and farmers may aware them differently, which affects the wheat breeding goals and hence varietal choices and adoption. It is crucial to assess individual farming systems, and farmers need to understand the prevailing factors and preferred attributes. These conditions affect the varietal choices of farmers, the design of the variety for a demand-led wheat breeding program, and the design of an effective disease control measure.\u003c/p\u003e \u003cp\u003eStem rust or black rust caused by (\u003cem\u003ePuccinia graminis f. sp. tritici\u003c/em\u003e) is a serious wheat disease causing a decrease in wheat production in many areas of the world [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Stem rust occurs mainly in warm weather regions and can cause severe losses when epidemics occur [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].Rust fungi spread in the form of clonally produced dikaryotic urediospores, which can be dispersed by wind for thousands of kilometers from initial infection sites across different areas from continent to continent. Wheat rust epidemics can occur on a continental scale due to the widespread dispersal of urediospores [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Rust fungi are plant pathogens that pose a particularly high biosecurity threat because they can travel long distances, build up rapidly, and attack economically important plant species. The ability of rust pathogens to spread and build up rapidly also makes them extremely difficult to eradicate once introduced. Studies of rDNA sequence data have confirmed the long-held belief that \u003cem\u003eP. graminis\u003c/em\u003e is a genetically variable complex species [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. It comprises variants known as formae speciales (\u0026ldquo;special forms\u0026rdquo;; f. sp.), which are morphological identical but are specialized for different host species.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e1.2. Statement of the Problem\u003c/h2\u003e \u003cp\u003eWheat is among the most important staple food crops and a major diet that is consumed by more than 2.5\u0026nbsp;billion people worldwide [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. In Ethiopia, wheat import has increased through years and in the last five years, Ethiopia imported on average 1.5\u0026nbsp;million tons of wheat at an average cost of 700\u0026nbsp;million dollars annually. The demand for wheat in Ethiopia has increased over the years due to rapid population growth and urbanization, which required a change in food preferences, which are easy and fast to prepare, such as bread, biscuits, pasta, noodles, and wheat flour porridge. This has forced Ethiopians to expand local wheat production as much as possible and look for alternatives that include changing food habits [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. The increase in demand for wheat has presented an opportunity for greater wheat production in Ethiopia. In Ethiopia, even if the wheat area is large, the yield obtained per hectare is low compared to other countries. Low productivity is attributed to several factors, including an increase in the intensity of biotic stress (diseases and insect pests) and abiotic stress (drought and heat) and a slow rate of adoption of new agricultural technologies [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Therefore, understanding and prioritizing the main production constraints is crucial before embarking on the expansion of local wheat production.Despite the fact that the government started the wheat initiative in Ethiopia, the complex and interactive effects of biotic, abiotic and socioeconomic factors, particularly in smallholder farming systems, affect wheat production and productivity. Wheat stem rust caused by \u003cem\u003ePuccinia graminis\u003c/em\u003e f.sp. \u003cem\u003etritici\u003c/em\u003e is among the critical biotic factors affecting wheat production in Ethiopia. Disease is a major threat to wheat production around the world [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] and can cause 100% yield losses in wide areas during epidemic years [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eYield loss due to stem rust in Ethiopia was estimated to reach 100% in susceptible wheat varieties at times of disease epidemics [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Due to its variability and diverse races, the management of rust disease has been difficult, and the disease continues to cause significant yield losses. In relation to this, there is frequent failure of resistant wheat varieties due to changes in pathogen virulence. Recurrent rust epidemics remain the main driver of the change in bread wheat varieties in Ethiopia. Massive wheat scaling projects implemented by ICARDA and CIMMYT in partnership with EIAR led to dramatic changes where old rust-prone wheat varieties such as Kubsa were replaced with newer rust-resistant wheat [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. Varieties with a specific resistance gene usually remain effective only for a few years because the extreme selection pressure on the pathogen population with mutants results in a gain in virulence in the pathogen population for that particular gene. Due to sudden changes in stem rust race patterns, it is important to detect the resistance capacity of existing varieties.\u003c/p\u003e \u003cp\u003eThe frequent failure of resistant wheat varieties due to changes in pathogen virulence has increased the interest in chemical control of wheat rust for global food security [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. The lack of knowledge and awareness about the nature of the disease and the inappropriate use of fungicides are also the main limitations, particularly for small-scale farmers. Farmers spray fungicides simply after they observe damaged crop, but plants may not show obvious disease symptoms until 7 to 15 days after infection. This means that after the spore is landed on the neighbor alternate host. The sprayed fungicide may protect the crop from disease for a given time, and after a time new epidemics can occur due to the repeating uredinial stage of the pathogen. Therefore, it is essential to evaluate the frequency of application of fungicides for effective and sustainable wheat rust management. Nitrogen (N) is the most important fertilizer element that determines the productivity of wheat. Previous research done on this area shows that nitrogen (N) is not only an important nutritional factor that promotes crop growth and increases crop yield but is also known to directly impact the severity of rust and powdery mildew disease [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. Regardless of the importance and wide use of nitrogen fertilizers in wheat production, there is limited knowledge on its effect on the development of rust disease in Ethiopia. \u003cem\u003eTherefore, it is important to assess the effect of nitrogen fertilizer on wheat stem rust. The current research was designed to develop an integrated wheat stem rust management strategy for the hot spot wheat production area of Ethiopia.\u003c/em\u003e\u003c/p\u003e \u003cp\u003e \u003cb\u003e1.3. Specific objective\u003c/b\u003e \u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eTo evaluate the effect of nitrogen fertilizer rates, fungicide frequencies and wheat varieties on wheat stem rust.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"2. MATERIALS AND METHODS","content":"\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Description of the study area\u003c/h2\u003e \u003cp\u003eThe field experiment was conducted at the Ambo Agricultural Research Center (AARC) in West Shoa, Ethiopia, during the main cropping season 2022. The center was located at 08\u0026deg; 57'N latitude and 38\u0026deg; 07'E longitude, at an altitude of 2225 ma sl. The soil type is heavy clay (vertisol) with a pH of 7.8 for the most top soil (0\u0026ndash;30 cm). The long-term total annual rain fall is 1115 mm, and the average minimum and maximum temperature are 11.7 and 25.5\u003csup\u003eo\u003c/sup\u003eC\u003csup\u003e,\u003c/sup\u003e respectively.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Treatments, Experimental Design, and Field Management\u003c/h2\u003e \u003cp\u003eThe field experiment included three varieties (Ogolcho, Kingbird, and Wane), a fungicide (Nativo\u003csup\u003eR\u003c/sup\u003e SC 300: tebuconazole 200g/l\u0026thinsp;+\u0026thinsp;trifloxystrobin 100g/l) in two application frequency i.e. 1 (once), and 2 (twice at 15 days interval) and three fertilizer rates (i.e. 100, 150 and 200kg nitrogen ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e). The fungicide was applied at a recommended rate of 0.75l / ha in 250 liters/ha of water using a manual knapsack sprayer. Varieties were selected based on their response to stem rust, with Ogolcho being susceptible, Kingbird moderately resistant, and Wane resistant. All varieties were seeded at the recommended rate of 150 kg seed ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and sowing date was July 5/2022. The experiment was laid out in a split-split- plot design with three replications. In the current study, fertilizer was assigned to the main plot, while fungicide frequency and varieties were assigned to the subplot and sub-subplots, respectively. This was done to minimize the risk of drifting fertilizers and fungicides.\u003c/p\u003e \u003cp\u003eThe total area of an experiment was 554m\u003csup\u003e2\u003c/sup\u003e (19.8m x 28m) with main plot size of 44.8m\u003csup\u003e2\u003c/sup\u003e (5.6m*8m) and sub-sub plot size 2.4m\u003csup\u003e2\u003c/sup\u003e. (1.2m x 2m). Sowing was carried out by manual drilling into 1.2 meters long of six rows with 0.2m space apart. Each plot (2.4 m\u003csup\u003e2\u003c/sup\u003e) received 36g of seed. The distance between the sub-plots, main plots and blocks was 1m, 1.5m and 2m, respectively. The stem rust spreader rows (mixture of susceptible cultivars, Kubsa and Morocco) were planted perpendicular to all entries to facilitate inoculum accumulation and uniform dissemination. The TSP fertilizers were applied at the rate of 200 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e during planting while, UREA was applied at the knee stage of the crop before heading based on each treatment level. Weeds were controlled by hand weeding to make the wheat field free of weed.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Data Collected\u003c/h2\u003e \u003cdiv id=\"Sec8\" class=\"Section3\"\u003e \u003ch2\u003e2.3.1 Disease-related data\u003c/h2\u003e \u003cp\u003eTo determine the response of wheat varieties to stem rust, data on disease incidence and severity were recorded on plot basis from the central four rows of the plot (1.6m\u003csup\u003e2\u003c/sup\u003e net area). In each plot, 10 plants were randomly selected and pre-tagged to record the severity of stem rust. The reactions of the varieties were scored 4 times in a 12 day interval starting from the onset of the disease and the associated symptoms.\u003c/p\u003e \u003cp\u003e \u003cb\u003eThe incidence of stem rust\u003c/b\u003e was recorded as the proportion of wheat plants with symptoms and signs of stem rust.\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:\\text{D}\\text{i}\\text{s}\\text{e}\\text{a}\\text{s}\\text{e}\\:\\text{i}\\text{n}\\text{c}\\text{i}\\text{d}\\text{e}\\text{n}\\text{c}\\text{e}\\:\\left(\\text{\\%}\\right)=\\:\\frac{\\text{N}\\text{u}\\text{m}\\text{b}\\text{e}\\text{r}\\:\\text{o}\\text{f}\\:\\text{d}\\text{i}\\text{s}\\text{e}\\text{a}\\text{s}\\text{e}\\text{d}\\:\\text{p}\\text{l}\\text{a}\\text{n}\\text{t}}{\\:\\text{T}\\text{o}\\text{t}\\text{a}\\text{l}\\:\\text{n}\\text{u}\\text{m}\\text{b}\\text{e}\\text{r}\\:\\text{o}\\text{f}\\:\\text{p}\\text{l}\\text{a}\\text{n}\\text{t}\\:\\text{a}\\text{s}\\text{s}\\text{e}\\text{s}\\text{s}\\text{e}\\text{d}}*100$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003eDisease \u003cb\u003eseverity\u003c/b\u003e was measured as a percentage of stem/leaf area covered by rust disease adopted by the modified Cobb scale (Peterson \u003cem\u003eet al\u003c/em\u003e., 1948).\u003cdiv id=\"Equb\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equb\" name=\"EquationSource\"\u003e\n$$\\:\\text{D}\\text{i}\\text{s}\\text{e}\\text{a}\\text{s}\\text{e}\\:\\text{S}\\text{e}\\text{v}\\text{e}\\text{r}\\text{i}\\text{t}\\text{y}\\:\\left(\\text{\\%}\\right)=\\:\\frac{\\text{A}\\text{r}\\text{e}\\text{a}\\:\\text{o}\\text{f}\\:\\text{s}\\text{t}\\text{e}\\text{m}\\:\\text{a}\\text{f}\\text{f}\\text{e}\\text{c}\\text{t}\\text{e}\\text{d}}{\\:\\text{T}\\text{o}\\text{t}\\text{a}\\text{l}\\:\\text{s}\\text{t}\\text{e}\\text{m}\\:\\text{a}\\text{r}\\text{e}\\text{a}\\:\\text{o}\\text{f}\\:\\text{p}\\text{l}\\text{a}\\text{n}\\text{t}}*100$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eCoefficient of infection (CI)\u003c/strong\u003e \u003cp\u003eAccording to Saari and Wilcoxson [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], the average coefficient of infection (CI) was calculated by multiplying the constant value assigned to each type of reaction by the percentage severity. Constant values for the various reaction types varied (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eArea under disease progress curve (AUDPC)\u003c/strong\u003e \u003cp\u003eStem rust disease severity scores taken at different times were used to calculate the area under disease progress curve (AUPDC) of each treatment adopted from Wilcoxson \u003cem\u003eet al\u003c/em\u003e. [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv id=\"Equc\" class=\"Equation\"\u003e \u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equc\" name=\"EquationSource\"\u003e\n$$\\:\\text{A}\\text{U}\\text{D}\\text{P}\\text{C}={\\sum\\:}_{n=1}^{n-1}\\:0.5\\left(xi+1+xi\\:\\left)\\right(ti+1+ti\\right)$$\u003c/div\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003eWhere, x\u003csub\u003ei\u003c/sub\u003e=the average coefficient of infection of the ith record, Xi\u0026thinsp;+\u0026thinsp;1\u0026thinsp;=\u0026thinsp;the average coefficient of infection of the i\u0026thinsp;+\u0026thinsp;1 record and t i\u0026thinsp;+\u0026thinsp;1-ti\u0026thinsp;=\u0026thinsp;the number of days between the i\u003csup\u003eth\u003c/sup\u003e record and the i\u0026thinsp;+\u0026thinsp;1 record, and n\u0026thinsp;=\u0026thinsp;number of observations.\u003c/p\u003e \u003cp\u003eThe type of reaction of wheat plants to stem rust was designated following the procedure proposed by Wilcoxson \u003cem\u003eet al\u003c/em\u003e. [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e] (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\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\u003eReaction type and values of the reaction type of wheat crop against wheat stem rust\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReaction type\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eValues of Reaction type\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSize of uredinial\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eResistant (R)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSmall uredinial surrounded by small chlorosis or necrosis.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eResistant to moderately resistant (R-MR)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eMedium size uredinial surrounded by small chlorosis or necrosis.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModerately resistant (MR)\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\u003eSmall uredinial surrounded by medium chlorosis or necrosis.\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eModerately susceptible (MS)\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\u003eMedium large compatible uredinial without chlorosis and necrosis\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSusceptible\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLarge, compatible uredinial without chlorosis and necrosis\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eWilcoxson \u003cem\u003eet al\u003c/em\u003e. (1975).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003e2.3.2 Yield and yield related data\u003c/h2\u003e \u003cp\u003e \u003cstrong\u003ePlant height (PH) (cm)\u003c/strong\u003e \u003cp\u003eThe height of 10 randomly sampled plants from the central rows of each plot was measured from the bases of the ground to the top of the spike excluding awns and the average of the ten observations will be used for analysis.\u003c/p\u003e \u003c/p\u003e \u003cp\u003eThe four central rows were harvested for grain and biomass yield from each plot, leaving the border to avoid border effects. The grain moisture content was adjusted to 12%. Data were collected on:\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eDry matter (biomass)\u003c/strong\u003e \u003cp\u003eThe total weight of the above ground part including the grain.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eThousand seeds weight (TSW)\u003c/strong\u003e \u003cp\u003eThe weight of 1000 seeds was determined by carefully counting the grains; and weighing them using a sensitive balance.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eGrain Yield (GY/ha)\u003c/strong\u003e \u003cp\u003eThe weight of all the kernels after harvesting was measured in grams per plot and converted into kg/ha for analysis.\u003c/p\u003e \u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Data Analysis\u003c/h2\u003e \u003cp\u003eThe incidence, severity and AUDPC data from the disease were subjected to analysis of variance (ANOVA) using the R software package version 4.1.0. Least Significant Difference (LSD) at the 0.05 probability level was used for mean separation.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. RESULT AND DISCUSSION","content":"\u003cdiv id=\"Sec12\" class=\"Section3\"\u003e \u003cdiv class=\"Heading\"\u003e3.2.1. Final severity of stem rust\u003c/div\u003e \u003cp\u003eThere were significant differences \u003cem\u003e(p\u0026thinsp;\u0026lt;\u0026thinsp;0.01)\u003c/em\u003e differences in the final values of the rust stem rust severity (FRS) between the N rates, the varieties, and the frequencies of application of fungicides(Appendix Table\u0026nbsp;1). The highest final severity of stem rust of 77% was scored in the susceptible variety (Ogolcho) with 200 kg/ha of N fertilizer and no application of fungicide. The FRS was significantly reduced (to up to 0%) as a result of the application of the fungicide once and twice (tebuconazole 200g/lt\u0026thinsp;+\u0026thinsp;tryfloxystrobin 100g/l), across varieties and nitrogen fertilizer rates. An FRS of 52% was scored on the same variety (Ogolcho) with a fertilizer rate of 150kg / ha of N without fungicide protection. In plots that did not receive fungicide application, the lowest FRS (11.6%) was recorded in the Kingbird variety with 100kg N/ha (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The application of the fungicide did not cause significant variation in FRS in the moderately resistant Kingbird variety. Also, this variety reacted more or less the same or even better, in some cases, compared to the Wane variety, which is considered resistant to wheat stem rust. The current results suggest a differential response of wheat varieties to stem rust according to the rate of N fertilizer application and the frequencies of fungicide application. The present results were in agreement with the findings of previous work by several scholars who reported that the rate of disease progress depends on the resistance level of the host used during the growing period and the supplemented management options [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn the present work, varieties receiving 100 or 150 Kg N / ha together with a once or twice fungicide application had significantly lower FRS compared to 200KgN/ha and no fungicide application. The higher FRS in wheat varieties as a result of the highest N rate (200 kg / ha) could be linked to increased susceptibility as a result of plants becoming more succulent. Stakman and Aamodt [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] also concluded that the wall of plant fertilized with excess nitrogen is thinner than they normally would be and parasitic fungi therefore can penetrate more easily. Rust severity may be further increased by excessive nitrogen fertilization resulting in denser stands and delayed maturity [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. In the same manner, wheat overfertilized with nitrogen especially when there was insufficient supply of potash or phosphorus, also nearly always was severely rusted. Stakman and Aamodt [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e] have also demonstrated the effect of fertilizer on wheat infection by \u003cem\u003eP. graminis\u003c/em\u003e. Similarly, wheat grown on an insufficiently fertilized soil could also suffer the greatest damage from stem rust. Therefore, the balance of soil nutrients is very important to improve wheat productivity, especially in areas of high disease pressure.\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\u003eEffect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on final rust severity and coefficient of infection of wheat stem rust\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eFinal rust severity\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eCoefficient of infection\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eNitrogen kg/ha\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariety\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e76.7\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5\u003csup\u003ejk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003csup\u003ejk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e76.7\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5\u003csup\u003eghi\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23.3\u003csup\u003ee\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003csup\u003ejk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e16\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.6\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0\u003csup\u003ej\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e33.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10\u003csup\u003ehl\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.7\u003csup\u003ekl\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13.3\u003csup\u003ede\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e07\u003csup\u003ej\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e150\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51.67\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.67\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.67\u003csup\u003elk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e51.67\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.66\u003csup\u003eghi\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.7\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e13.3\u003csup\u003egh\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4j\u003csup\u003ek\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0 \u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7.33\u003csup\u003efgh\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.73\u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0 \u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18.3\u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5\u003csup\u003ejk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0 \u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.67\u003csup\u003efg\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.67\u003csup\u003ejkl\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0 \u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e28.33\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.3\u003csup\u003ekl\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.7\u003csup\u003ekl\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e26.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.2\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0\u003csup\u003ej\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11.67\u003csup\u003ej\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4\u003csup\u003ejk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.7\u003csup\u003ehi\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.5\u003csup\u003ehij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0\u003csup\u003ej\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e16.67\u003csup\u003efg\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5\u003csup\u003ejk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6.7\u003csup\u003efgh\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.7\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0\u003csup\u003ej\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCV \u003csub\u003e(%)\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003e19.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e24.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLSD\u003csub\u003e(0.05)\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e3.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eLSD\u003csub\u003e0.05\u003c/sub\u003e= List of significant differences at%, CV\u0026thinsp;=\u0026thinsp;Coefficient of variation. Means with the same letter are not significantly different for each variable.\u003c/p\u003e \u003cp\u003eConsistent with this study, Tadesse \u003cem\u003eet al\u003c/em\u003e. [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]; Wubishet and Tamene [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e] and Foster \u003cem\u003eet al.\u003c/em\u003e [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e] found that the integration of variety and fungicide application reduced disease levels and increased crop yield attributes. Phillip and Nathan [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e] also noted similar results on wheat diseases that fungicide significantly reduced disease severity and increased yield parameters over the unsprayed plots.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section3\"\u003e \u003cdiv class=\"Heading\"\u003e3.2.2. Coefficient of infection\u003c/div\u003e \u003cp\u003eThe infection coefficient (CI) was significantly \u003cem\u003e(p\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/em\u003e) affected by the treatment combinations (Appendix Table\u0026nbsp;1). In general, CI of the stem rust in wheat varieties varied with the increase in the rate of fertilizer N and the decrease in the frequency of application of fungicides. Wheat plots that received the highest nitrogen fertilizer without fungicide spray had higher CI values that reached up to 76.7 in the susceptible variety (Ogolcho) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). In line with this, a significant effect of nitrogen fertilizer rate on CI was also evidenced by the study of Ali \u003cem\u003eet al.\u003c/em\u003e [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section3\"\u003e \u003cdiv class=\"Heading\"\u003e3.2.3. Area under stem rust progress curve\u003c/div\u003e \u003cp\u003eAnalysis of variance indicated that the interaction of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties showed significant differences \u003cem\u003e(p\u0026thinsp;\u0026lt;\u0026thinsp;0.01)\u003c/em\u003e in the area under the stem rust progress curve and the relative area under the stem rust progress curve (Appendix Table\u0026nbsp;1).The AUDPC values ranged from 5.3% days in the resistant variety (Wane) with 100kg N/ha on plot without fungicide to 1250% in days in the susceptible variety (Ogolcho) (200 kg N / ha) without fungicide while the moderately resistant Kingbird variety had intermediate AUDPC values of stem rust. In general, the AUDPC values of stem rust increased with increasing N fertilization rate and decreasing application of fungicides. As stated by Van der Planck [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e], the disease progress curve was a better indicator of disease expression over time. Therefore, the selection of cultivars with lower AUDPC values is acceptable for practical purposes.\u003c/p\u003e \u003cp\u003eIn the present study, nitrogen fertilizer rate and fungicide frequency lacked consistently significant influence on moderately resistant variety (Kingbird) and resistant variety (Wane). In contrast, the susceptibility of the Ogolcho variety increased with the application of nitrogen fertilizer. Current results were in line with those of Viljanen-Rollinson \u003cem\u003eet al\u003c/em\u003e. [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e], who reported that the more resistant cultivars had very low AUDPCs and would probably not benefit from an application of fungicide to control wheat rust, unless the pathotypes present were highly virulent against these cultivars. The results obtained in the current work were also in agreement with the findings of Haggag \u003cem\u003eet al.\u003c/em\u003e [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e] that confirmed the effect of nitrogen fertilizer on susceptible variety. Phillip and Nathan [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e] reported that the highest value of AUDPC for yellow and stem rust was due to the highest disease development in plots that did not spray with any combinations of crop varieties and fungicide applications; the moderately resistant varieties had the lowest AUDPC for yellow and stem rust diseases when supplemented with fungicide application. The work of Fleitas \u003cem\u003eet al.\u003c/em\u003e [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e] also revealed that plants that receive high N fertilization are more susceptible to leaf rust. However, the current findings contradicted the results of Stakman and Aamodt [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e], who reported no fundamental changes in the degree of physiological resistance to stem rust when plants were supplied with nitrogen fertilizer. The less frequent sprays allowed the development of multiple levels of epidemics and were not effective in controlling the disease in Ogolcho, as the severity of stem rust is very high in this variety. These results reiterate the role of varietal resistance in determining the frequency and effectiveness of chemical sprays once rust has been established. Regarding the effect of fungicides, it has been reported that fungicides reduced subsequent disease progress on plant parts that were slightly infected at the time of fungicide application, but were not effective on plant parts that were heavily infected. Therefore, rust control strategy through fungicides must consider the time of onset, early detection of the disease, and early application of fungicides if economic control of the disease is intended [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec15\" class=\"Section3\"\u003e \u003cdiv class=\"Heading\"\u003e3.2.4. Relative area under stem rust progress curve\u003c/div\u003e \u003cp\u003eThe highest rAUDPC of 172.3, 88.2, 39.5 were recorded in unsprayed plots of the susceptible variety (Ogolcho) at nitrogen fertilizer levels of 200, 150, 100 kg / ha, respectively (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The significant effect of nitrogen fertilizer on rAUDPC was observed in only susceptible varieties, while the other two varieties showed significantly lower rAUDPC regardless of the N rate.\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\u003eEffect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on area under stem rust progress curve and relative area under stem rust progress curve\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eAUDPC\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003erAUDPC\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eNitrogen kg/ha\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariety\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1250a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e277.9\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e231.3\u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e172.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e38.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e31.9\u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e74.7\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e69.1\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e51.1\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e10.3\u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9.5\u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e53\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e30.1\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9.4\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.3\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.2\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e150\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e640\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e322.5\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e183.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e88.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e81.1\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e25.3\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e57.3\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.3\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e23.9 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7.9\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.1\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.3 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e91.3\u003csup\u003ee\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e20.7\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.5\u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e12.6\u003csup\u003ee\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.8\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.8\u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e286.5 \u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e179.7\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e171.3\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e39.5 \u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e24.8 \u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e23.6 \u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e37.3 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e14.7 \u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e16.1 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.1 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2 \u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.2 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e38.7 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e18.\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.3 \u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.3 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.5 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.7 \u003csup\u003ef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCV (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003e27.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e27.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLSD\u003csub\u003e(0.05)\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003e75.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e10.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eLSD\u003csub\u003e0.05\u003c/sub\u003e= List of significant differences in%, CV\u0026thinsp;=\u0026thinsp;Coefficient of variation, AUDPC\u0026thinsp;=\u0026thinsp;Area under disease progress curve, rAUDPC\u0026thinsp;=\u0026thinsp;relative area under disease progress curve. Means with the same letter are not significantly different for each variable.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003e3.3. Yield and yield related parameters\u003c/h2\u003e \u003cdiv id=\"Sec17\" class=\"Section3\"\u003e \u003ch2\u003e3.3.1. Plant Height and Biomass\u003c/h2\u003e \u003cp\u003eThere was a significant difference \u003cem\u003e(p\u0026thinsp;\u0026lt;\u0026thinsp;0.05)\u003c/em\u003e in plant height between tested varieties, fertilizer rate, and frequency of application of fungicides (Appendix Table\u0026nbsp;2). The height of the plant ranged from 68.4 cm in the unsprayed Wane variety treated with 100kg/ha of nitrogen fertilizer to 96.6 cm in the Ogolcho variety treated with 200kg/ha of N fertilizer sprayed twice with Nativo\u003csup\u003eR\u003c/sup\u003e SC 300. The Kingbird variety had an intermediate plant height that was not significantly affected by the nitrogen fertilizer rate. The application of fungicides had a significant effect on the height of the susceptible wheat variety (Ogolcho), while no such effect was observed in the resistant (Wane) and moderately resistant (Kingbird) varieties (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).There was a significant difference in dry biomass due to nitrogen level and variety, but the results were not consistent. Ogolcho and Kingbird recorded a higher biomass yield than Wane on sprayed plots with higher nitrogen fertilizer rates. A significant effect of the fungicide on the biomass of the plant was evident on the susceptible variety (Ogolcho). The highest biomass (11666.7 kg/ha) for Ogolcho variety was recorded from sprayed plots once and twice with higher fertilizer rates (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eEffect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on plant height and biomass yield under wheat stem rust epidemics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003ePlant height (cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eBiomass yield (kg/ha)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eNitrogen kg/ha\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVariety\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e91.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e92.8\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e96.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e10937.5\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11666.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e11666.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e83.4\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;g\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80.6\u003csup\u003ee\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e81.3\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e10937\u003csup\u003ea\u0026thinsp;\u0026minus;\u0026thinsp;c\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11354\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10312\u003csup\u003ea\u0026thinsp;\u0026minus;\u0026thinsp;d\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e79.6\u003csup\u003egh\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e79\u003csup\u003egh\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e80.1\u003csup\u003ef\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9583.3\u003csup\u003ec\u0026thinsp;\u0026minus;\u0026thinsp;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9791.6\u003csup\u003ec\u0026thinsp;\u0026minus;\u0026thinsp;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9583.3\u003csup\u003ec\u0026thinsp;\u0026minus;\u0026thinsp;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e150\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e89.8\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e91.9\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e93.2\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9687.5\u003csup\u003ec\u0026thinsp;\u0026minus;\u0026thinsp;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10416\u003csup\u003ea\u0026thinsp;\u0026minus;\u0026thinsp;d\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10104\u003csup\u003eb\u0026thinsp;\u0026minus;\u0026thinsp;e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e81.6\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e79.5\u003csup\u003egh\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e10104\u003csup\u003eb\u0026thinsp;\u0026minus;\u0026thinsp;e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10625\u003csup\u003ea\u0026thinsp;\u0026minus;\u0026thinsp;c\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10000\u003csup\u003eb\u0026thinsp;\u0026minus;\u0026thinsp;e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e81\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;g\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e79.5\u003csup\u003egh\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9166.6\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;g\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8750\u003csup\u003ee\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8750\u003csup\u003ee\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e85\u003csup\u003ec\u0026thinsp;\u0026minus;\u0026thinsp;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e85.8\u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e85.7\u003csup\u003ec\u0026thinsp;\u0026minus;\u0026thinsp;e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8125\u003csup\u003eg\u0026thinsp;\u0026minus;\u0026thinsp;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7708.3\u003csup\u003eh\u0026thinsp;\u0026minus;\u0026thinsp;j\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8437.5\u003csup\u003ef\u0026thinsp;\u0026minus;\u0026thinsp;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e82\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e82\u003csup\u003ed\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e77.3\u003csup\u003ehi\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7083.3\u003csup\u003ei\u0026thinsp;\u0026minus;\u0026thinsp;k\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7083.3\u003csup\u003ei\u0026thinsp;\u0026minus;\u0026thinsp;k\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7916.6\u003csup\u003eg\u0026thinsp;\u0026minus;\u0026thinsp;j\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68.4\u003csup\u003ej\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.6\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e73\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6666.6\u003csup\u003ejk\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7291.6\u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5833.3\u003csup\u003ek\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCV \u003csub\u003e(%)\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003e\u003cb\u003e5.2\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003e9\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLSD\u003csub\u003e(0.05)\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003e\u003cb\u003e3.8\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003e1384.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eLSD\u003c/em\u003e \u003csub\u003e \u003cem\u003e0.05\u003c/em\u003e \u003c/sub\u003e \u003cem\u003e= List of significant different at %, CV\u0026thinsp;=\u0026thinsp;Coefficient of variation, PH\u0026thinsp;=\u0026thinsp;Plant height, BM\u0026thinsp;=\u0026thinsp;biomass. Means with the same letter are not significantly different for each variable.\u003c/em\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section3\"\u003e \u003ch2\u003e3.3.2. Grain yield\u003c/h2\u003e \u003cp\u003eWheat grain yield differed by nitrogen rate, fungicide application frequency and wheat varieties, although the results were not consistently significant (Appendix Table\u0026nbsp;2). The highest grain yield of 3627 kg/ha was obtained from the resistant variety Wane) with two fungicide sprays and the highest N fertilization rate (200kg/ha). On the other hand, the lowest wheat grain yield of 1393kg/ha was recorded from the Kingbird variety without fungicide spray and 100kgN/ha. Generally, wheat grain yield increased with fungicide sprays and N fertilization rate. But the difference in yield was not significant in many instances except between 100 and 200kgN/ha (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eEffect of nitrogen fertilizer rate, fungicide application frequencies, and bread wheat varieties on TSW and wheat yield under wheat stem rust epidemics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"10\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003eYield (kg/ha)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003eThousand seed weight (g)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eNitrogen kg/ha\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c3\" namest=\"c2\" rowspan=\"2\"\u003e \u003cp\u003eVariety\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003eFungicide Frequency\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003eOnce\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003eTwice\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e200\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3271\u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3610\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3624.2 \u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e38 \u003csup\u003ef\u0026minus;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e44 \u003csup\u003ea\u0026minus;d\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e46 \u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2579 \u003csup\u003eg\u0026minus;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2723 \u003csup\u003ef\u0026minus;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2945\u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e38.7 \u003csup\u003ef\u0026minus;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e37.1 \u003csup\u003eg\u0026minus;j\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e37 \u003csup\u003eg\u0026minus;j\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3320\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3515\u003csup\u003ea\u0026thinsp;\u0026minus;\u0026thinsp;c\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3627 \u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e41 \u003csup\u003ec\u0026minus;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e42.5 \u003csub\u003eb\u0026minus;e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e43 \u003csup\u003eb\u0026minus;d\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e150\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3275 \u003csup\u003ecd\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3477\u003csup\u003eabc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3589\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e41 \u003csup\u003ed\u0026minus;g\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e44.2 \u003csup\u003ea\u0026minus;d\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e47.3 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2479\u003csup\u003eg\u0026thinsp;\u0026minus;\u0026thinsp;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2417.8 \u003csup\u003eij\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2637\u003csup\u003eg\u0026thinsp;\u0026minus;\u0026thinsp;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e37 \u003csup\u003eh\u0026minus;k\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e35\u003csup\u003ei\u0026thinsp;\u0026minus;\u0026thinsp;k\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e36.1 .\u003csup\u003e3\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2553\u003csup\u003eg\u0026thinsp;\u0026minus;\u0026thinsp;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2928.9 \u003csup\u003eef\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3015\u003csup\u003ede\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e39.2 \u003csup\u003ee\u0026minus;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e42.1 \u003csup\u003eb\u0026minus;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e44.6 \u003csup\u003ea\u0026minus;c\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003e100\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eOgolcho\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2453\u003csup\u003eh\u0026thinsp;\u0026minus;\u0026thinsp;j\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2676\u003csup\u003ef\u0026thinsp;\u0026minus;\u0026thinsp;i\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2765 \u003csup\u003ee\u0026minus;g\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e40.7 \u003csup\u003ed\u0026minus;g\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e44.0 \u003csup\u003ea\u0026minus;d\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e44.1 \u003csup\u003ea\u0026minus;d\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eKingbird\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1393\u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1859.3 \u003csup\u003ek\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1752\u003csup\u003ek\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e33.9 \u003csup\u003ej\u0026minus;l\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e31.1 \u003csup\u003el\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e33 \u003csup\u003ekl\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eWane\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2174.\u003csup\u003e1j\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2400.1\u003csup\u003ei\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1752\u003csup\u003ek\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e39\u003csup\u003ee\u0026thinsp;\u0026minus;\u0026thinsp;h\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e41.5 \u003csup\u003ec\u0026minus;f\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e42.5 \u003csup\u003eb\u0026minus;e\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCV \u003csub\u003e(%)\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e\u003cb\u003e6.3\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c10\" namest=\"c7\"\u003e \u003cp\u003e\u003cb\u003e5.5\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eLSD\u003csub\u003e(0.05)\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e\u003cb\u003e290.7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c9\" namest=\"c7\"\u003e \u003cp\u003e\u003cb\u003e3.7\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"1\" nameend=\"c10\" namest=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eLSD\u003c/em\u003e \u003csub\u003e \u003cem\u003e0.05\u003c/em\u003e \u003c/sub\u003e \u003cem\u003e= List of significant differences at%, CV\u0026thinsp;=\u0026thinsp;Coefficient of variation. Means with the same letter are not significantly different for each variable.\u003c/em\u003e \u003c/p\u003e \u003cp\u003eThe application of fungicides once to twice was effective in obtaining higher yields. Estimating yield loss by a disease is a prerequisite to develop strategies for disease control particularity through breeding objectives for disease resistance [\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section3\"\u003e \u003ch2\u003e3.3.3. Thousand Seed weight\u003c/h2\u003e \u003cp\u003eAnalysis of variance revealed the significant effect \u003cem\u003e(p\u0026thinsp;\u0026lt;\u0026thinsp;0.01\u003c/em\u003e) of nitrogen rate, frequency of application of fungicides and wheat varieties on thousand seed weights (Appendix Table\u0026nbsp;2). Treatments with a two-time fungicide spray frequency had significantly higher thousand seed weights than once sprayed and untreated plots. The highest thousand seed weight of 47.3 g was recorded in the susceptible variety (Ogolcho) with two fungicide sprays and 150kgN/ha. On the other hand, the lowest thousand seed weight of 31g was recorded from the moderately resistant variety (Kingbird) with one fungicide spray and 100kgN/ha. Thousand seed weights (TSW) in untreated plots of highly N fertilizer rate plots ranged from 38g in susceptible variety (Ogolcho) to 41g in resistant variety (Wane). The TSW of the twice treated plot with highly fertilized plots ranged from 37 g in the moderately resistant variety (Kingbird) to 46 g and in the susceptible variety (Ogolcho). On the other hand, unsprayed plots fertilized with 150kgN/ha had a thousand seed weights of 37 on the moderately resistant variety and 41g and on the susceptible variety (Ogolcho) (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eRegarding the frequency of fungicide spray, TSW in two sprayed plots varied from 33 g for the moderately resistant variety with 100kgN/ha to 47.3 g for the susceptible variety with 150kgN/ha. The susceptible variety Ogolcho sprayed once and twice with Nativo and treated with 200kg/ha had a better thousand seed weight and has a relatively equal grain yield with the resistant variety. Nzuve \u003cem\u003eet al\u003c/em\u003e. [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e] reported that stem rust significantly reduces TKW in wheat. He also indicated that the significant effect of stem rust on TKW is brought about by its effect on photosynthesis and subsequent grain filling. According to [\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e, \u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e, \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e], the competition of rust fungi for photosynthates in grain filling would have increased importance in reducing the number and size of seeds in plants. In this study, no protected check plot was established for each treatment to obtain information to calculate yield loss.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e"},{"header":"4. CONCLUSION","content":"\u003cp\u003eWheat is one of the most important crops in Ethiopia and around the world. However, the crop is affected by abiotic and biotic constraints, of which stem rust caused by \u003cem\u003eP. graminis f.sp. tritici\u003c/em\u003e is one. The results of the current field experiment revealed a significant effect of the variety of wheat, the rate of N fertilizer and the frequency of fungicides on the development of wheat stem rust, the yield and related parameters of wheat. Regardless of fungicide applications, stem rust was less severe in moderately resistant varieties (Kingbird) and resistant varieties (Wane) compared to susceptible varieties (Ogolcho). The less severe disease was mainly due to the inherent nature of the varieties to resist rust epidemics, although the weather conditions at the experiment site appeared to be conducive to the development of the disease. Similarly, current results demonstrated that stem rust epidemics were different at the three N fertilizer rates (ie 100, 150 and 200 kg/ha). High stem rust intensity was observed in unsprayed plots with a high nitrogen fertilizer rate and this may be due to the effect of N on disease through changes in canopy microclimate caused by increased canopy size. The unsprayed plots exhibited higher disease intensity rates, while twice the application of Nativo\u003csup\u003eR\u003c/sup\u003e SC 300 fungicides (tebuconazole 200g/lt\u0026thinsp;+\u0026thinsp;tryfloxystrobin 100g / l) ensured better control of the development of stem rust.\u003c/p\u003e \u003cp\u003eThe integrated management of stem rust through nitrogen fertilizer rate, wheat varieties and fungicide spray frequency was highly associated with disease parameters, yield and yield components. The wane had the highest yielder (3,627 kg / ha) supplemented with a higher N fertilizer rate (200kg/ha) and twice the fungicide spray. The Ogolcho variety resulted in the highest TSW (47g) when supplemented with an intermidate N fertilizer level and twice the application of fungicide.Variation in the genetic background of the varieties, nitrogen level, and frequency of fungicide applications could have resulted in differences in GY and TKW in this study. Based on the response to yield of the wheat varieties tested in the current experiment, the varieties performed best when treated with 200 N fertilizer applied with a twice the frequency of the fungicide (tebuconazole 200g/lt\u0026thinsp;+\u0026thinsp;tryfloxystrobin 100g/l) at a 15-day interval. On the basis of the results, the following recommendations are made:\u003c/p\u003e \u003cp\u003e \u003cul\u003e \u003cli\u003e \u003cp\u003eFurther studies should be conducted on host resistance, fungicide application frequencies, and nitrogen fertilizer rate in multiple locations, years, and hot spot agro ecologies to stem rust to manage disease in a sustainable manner.\u003c/p\u003e \u003c/li\u003e \u003cli\u003e \u003cp\u003eThere must also be a plan to establish integrated management of wheat stem rust.\u003c/p\u003e \u003c/li\u003e \u003c/ul\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eA preprint of this article has been published by Gemechu\u003c/b\u003e \u003cb\u003eet al\u003c/b\u003e. \u003cb\u003e(47) with\u003c/b\u003e \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.researchsquare.com/article/rs-4293041/v1\u003c/span\u003e\u003cspan address=\"https://www.researchsquare.com/article/rs-4293041/v1\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eEthics Consent to participate\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eEthics approval and consent to participate\u003c/b\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eConsent for publication\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eCompeting interests\u003c/strong\u003e \u003cp\u003eThe authors declare there was no competing of interests.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eClinical trial\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eThis work did not receive any fund.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eConceptualization: Nigatu GemechuFormal analysis: Nigatu Gemechu \u0026amp; Garome ShifarawInvestigation: Nigatu GemechuMethodology: Nigatu GemechuSoftware: Garome Shifaraw \u0026amp; Nigatu GemechuSupervision: Alemayehu Chala \u0026amp; Jemal TolaValidation: Alemayehu Chala \u0026amp; Jemal TolaWriting \u0026ndash; original draft: Nigatu GemechuWriting \u0026ndash; review \u0026amp; editing: Garome Shifaraw, Alemayehu Chala \u0026amp; Jemal Tola\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eAll data generated or analyzed during the study are included in this manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eStatista. (2021). Worldwide mobile education app downloads from 1st quarter 2017 to 1st quarter 2020, by platform. Retrieved from \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.statista.com/statistics/1128262/mobile-education-app-downloads worldwide-platfor\u003c/span\u003e\u003cspan address=\"https://www.statista.com/statistics/1128262/mobile-education-app-downloads worldwide-platfor\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e ms-millions/.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFalola A, Achem BA, Oloyede WO, Olawuyi GO. Determinants of commercial production of wheat in Nigeria: A case study of Bakura Local Government Area, Zamfara State. Trakia J Sci. 2017;1:15\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNuttonson MY. 1957. Wheat-climatic relationships and the use of phenology in ascertaining the thermal and photo-thermal requirements of wheat.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUSDA. 2019. USDA world markets and Trade Report. Accessed on December 15, 2019.Vanderplank J., 1963. Plant Diseases: epidemics and control. Academic Press, New York.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZegeye F, Alamirew B, Tolossa D. Analysis of wheat yield gap and variability in Ethiopia. Int J Agricultural Econ. 2020;4:89\u0026ndash;98.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNegassa A, Shiferaw B, Koo J, Sonder K, Smale M, Braun H, Gbegbelegbe S, ZheGuo D, Wood S, Payne T, Abeyo B. 2013. The potential for wheat production in Africa.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMinot N, Warner J, Lemma S, Kasa L, Gashaw A, Rashid S. The wheat supply chain in Ethiopia: Patterns, trends, and policy options. Gates Open Research. 2019;3(174):174.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAmentae TK, Hamo TK, Gebresenbet G, Ljungberg D. Exploring wheat value chain focusing on market performance, post-harvest loss, and supply chain management in Ethiopia: The case of Arsi to Finfinnee market chain. J Agric Sci. 2017;9(8):22.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFAO. 2021. Food and Agricultural Organization of the United Nations (FAO): FAO Global Statistical Year book. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.fao.org/faostat/en/#data/QC\u003c/span\u003e\u003cspan address=\"http://www.fao.org/faostat/en/#data/QC\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. Meta data last certified Nov. 2017.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCSA. 2022. Agricultural sample survey of area and production of major crops. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.statsethiopia.gov.et/\u003c/span\u003e\u003cspan address=\"https://www.statsethiopia.gov.et/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. Accessed 2022 Jul 15.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNetsanat B, Shimelis H, Laing M. Appraisal of farmer\u0026rsquo;s wheat production constraints and breeding priorities in rust prone agro-ecologies of Ethiopia. Afr J Agric Res. 2017;12:944\u0026ndash;52.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSemahegn Y, Shimelis H, Laing M, Mathew I. Farmers\u0026rsquo; preferred traits and perceived production constraints of bread wheat under drought-prone agro-ecologies of Ethiopia. Agric Food Secur. 2021;10:18.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRoelfs AP. Estimated losses caused by rust in small grain cereals in the United States, \u003cem\u003e1918-\u003c/em\u003e. Volume 76. (Vol. 1356). Department of Agriculture, Agricultural Research Service; 1978.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eLeonard KJ, Szabo LJ. Pathogen profile: Stem rust of small grains and grasses caused by \u003cem\u003ePucciniagraminis\u003c/em\u003e. Mol Plant Pathol. 2005;6:99\u0026ndash;111.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKhan MH, Bukhari A, Dar ZA, Rizvi SM. 2013. Status and strategies in breeding for rust resistance in wheat.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eZambino P, Szabo L. Phylogenetic relationships of selected cereal and grass rusts based on rDNA sequence analysis. Mycologia. 1993;85:401\u0026ndash;14.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbbasi M, Goodwin S, Scholler M. Taxonomy, phylogeny, and distribution of Puccinia graminis, the black stem rust: new insights based on rDNA sequence data. Mycoscience. 2005;46:241\u0026ndash;7.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBentley AR, Donovan J, Sonder K, Baudron F, Lewis JM, Voss R, Rutsaert P, Poole N, Kamoun S, Saunders DGO, Hodson D, Hughes DP, Negra C, Ibba MI, Snapp S, Sida TS, Jaleta M, Tesfaye K, Becker-Reshef I, Govaerts B. Near- to long-term measures to stabilize global wheat supplies and food security. Nat Food. 2022;1\u0026ndash;4. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1038/s43016-022-00559- y\u003c/span\u003e\u003cspan address=\"10.1038/s43016-022-00559- y\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWuletaw T, Wondwosen SH, Tafesse S, Zewdie B. 2022. Wheat Production and Breeding in Ethiopia: Retrospect and Prospects.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNetsanet B, Getaneh W, Tsegab T, Berhanu B, Nigussie H. 2020. Survey and surveillance of wheat rusts in the major wheat growing areas of Ethiopia during 2017\u0026ndash;2019.Pp 13\u0026ndash;19. In D. Eshetu \u0026amp; G. Bedada, editors, Proceedings on the delivering genetic gain in wheat (DGGW) project closing workshop 120p. Ethiopian Institute of Agricultural Research.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKanti K, Rawal C, Rajdeep HD, Devanna JBN. Draft Genome of the Wheat Rust Pathogen (\u003cem\u003ePuccinia triticina\u003c/em\u003e) Unravels Genome-Wide Structural Variations during Evolution. Genome Biology Evolution; 2016.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePark RF. Stem rust of wheat in Australia. Australian J Agric Res. 2007;58:558\u0026ndash;66.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBechere E, Kebede H, Belay G. Durum wheat in Ethiopia: An old crop in an ancient land. Institute of Biodiversity Conservation and Research (IBCR); 2000. p. 68.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRowell J. Chemical control of the cereal rusts. Annual Rev Phytopathol. 1968;6:243\u0026ndash;62.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eChen Y, Zhang F, Tang L, Zheng Y, Li Y, Christie P, Li L. Wheat powdery mildew and foliar N concentrations as influenced by N fertilization and belowground interactions with intercropped faba bean. Plant Soil. 2007;291:1\u0026ndash;13.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDevadas R, Simpfendorfer S, Backhouse D, Lamb DW. Effect of stripe rust on the yield response of wheat to nitrogen. Crop Journa. 2014;1 2:201\u0026ndash;6.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSaari E, Wilcoxson R. Plant disease situation of high yielding durum wheat in Asia and Africa. Annu Rev Phytopathol. 1974;2:49\u0026ndash;68.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWilcoxson RD, Skovmand B, Atif AH. Evaluation of wheat cultivars ability to retard development of stem rust. Annual Appl Biology. 1975;80:275\u0026ndash;81.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMercer PC, Ruddock A. Disease management of winter wheat with reduced doses of fungicides in Northern Ireland. Crop Prot. 2005;24:221\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTadesse W, Bishaw Z, Assefa S. Wheat production and breeding in sub-Saharan Africa: Challenges and opportunities in the face of climate change. Int J Clim Change Strateg Manag. 2019;11:696\u0026ndash;715.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eStakman EC, Aamodt OS. The effect of fertilizers on the development of stem rust of wheat. Journal Agricultural Research. 1924;27:341\u0026ndash;79.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKnott DR, Knott DR. 1989. Genetic analysis of resistance. Wheat Rusts\u0026mdash;Breeding Resist pp.58\u0026ndash;83.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWuletaw T, Wondwosen SH, Tafesse S, Zewdie B. 2022. Wheat Production and Breeding in Ethiopia: Retrospect and Prospects.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFoster AJ, Lollato R, Vandeveer M, De Wolf ED. Value of Fungicide Application in Wheat Production in Southwest Kansas. Kans Agricultural Exp Stn Research Reports. 2017;3:5\u0026ndash;8.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePhillip NS, Nathan M. Evaluation of foliar fungicide programs in mid-Atlantic winter wheat production systems. Crop Prot. 2018;13:103\u0026ndash;10.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAli S, Shah SJA, Raman IKH, Maqbool K, Ullah W. Partial resistance to yellow rust in introduced winter wheat germplasm at the north of Pakistan. Aust J Crop Sci. 2009;3(1):37.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVan der Plank JE. 1963. Plant Diseases Epidemics and Control. New York \u0026amp; London.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eViljanen-Rollinson SLH, Armour T, Cromey MG. Fungicide control of strip rust in wheat: Protection or eradication. New Z plant Prot. 2002;55:336\u0026ndash;40.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHaggag ME, Eweida MH, El-Sayed FF. The effect of nitrogen application on the development of rusts on wheat varieties. Acta Mycologica. 1976;12(2):191\u0026ndash;4.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFleitas MC, Schierenbeck M, Gerard GS, Dietz JI, Golik SI, Campos PE, Sim\u0026oacute;n MR. How leaf rust disease and its control with fungicides affect dough properties, gluten quality and loaf volume under different N rates in wheat. J Cereal Sci. 2018;80:119\u0026ndash;27.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBeard C, Jayasena K, Thomas G, Loughman R. Managing Stem Rust of Wheat. Plant Pathology, Department of Agriculture, Western Australia; 2004.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSimmonds NW. 1988. Synthesis the strategy of rust resistance breeding N. W. Simmonds and S. Rajaram, editors, Breeding Strategies for Resistance to the Rusts of wheat. CIMMYT, Mexico. 119\u0026ndash;136 P.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNzuve FM, Bhavani S, Tusiime G, Njau P, Wanyera R. 2012. Evaluation of bread wheat for both seedling and adult plant resistance to stem rust. \u003cem\u003eAfrican Journal of Plant Science 6:426\u0026ndash; 432.\u003c/em\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAgrios GN. Plant Pathology. New York: Academic; 1988.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNigus M, Shimelis H, Mathew I, Abady S. Wheat production in the highlands of Eastern Ethiopia: opportunities, challenges and coping strategies of rust diseases. Acta Agriculturae Scand Sect B\u0026mdash;Soil Plant Sci. 2022;72(1):563\u0026ndash;75.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMengesha GG. 2020. Management of yellow rust (Puccinia striiformis f. sp. tritici) and stem rust (Puccinia graminis f. sp tritici) of bread wheat through host resistance and fungicide application in Southern Ethiopia. \u003cem\u003eCogent Food \u0026amp; Agriculture\u003c/em\u003e, \u003cem\u003e6\u003c/em\u003e(1), p.1739493.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGemechu N, Chala A, Tola J, Shifaraw G. 2024. Management of wheat stem rut (Puccinia graminis f. Sp. Tritici) through variety and nitrogen fertilizer application rate in the west Shoazone.\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.researchgate.net/publication/380121404_Management_of_wheat_stem_rut_Puccinia_graminis_fSp_Tritici_through_variety_and_nitrogen_fertilizer_application_rate_in_the_west_Shoa_zone\u003c/span\u003e\u003cspan address=\"https://www.researchgate.net/publication/380121404_Management_of_wheat_stem_rut_Puccinia_graminis_fSp_Tritici_through_variety_and_nitrogen_fertilizer_application_rate_in_the_west_Shoa_zone\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Disease progress, epidemics, fungicides, integrated disease management, rusts","lastPublishedDoi":"10.21203/rs.3.rs-7813373/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7813373/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eWheat stem rust (\u003cem\u003ePuccinia graminis f.sp. tritici\u003c/em\u003e) is a common fungal disease that causes significant yield reductions and grain quality deterioration. Therefore, this study was designed to investigate the efficiency of integrating different management strategies against stem rust (Sr) of wheat in the West Shoa zone during 2022/23 main growing season. A split-split plot design was used for field experiment using wheat varieties, the frequency of application of fungicides, and nitrogen fertilizer rates. The results of the field experiment revealed that a significant interaction effect of wheat variety, nitrogen fertilizer rate, and frequency of application of fungicides on disease intensity and wheat grain yield. The Wane wheat variety was found to be more resistant to stem rust, followed by Kingbird. Generally, the pressure of the disease increased with increasing nitrogen fertilizer rate from 100 to 200 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e. On the other hand, increasing the frequency of spraying of fungicides from 0 to 2 resulted in a lower disease pressure in all varieties. But, result is more pronounced on the susceptible wheat variety. The present findings confirmed that the role of integrated disease management may play in controlling stem rust epidemics. However, results should be verified through additional trials across agro ecologies and years.\u003c/p\u003e","manuscriptTitle":"Management of Wheat Stem Rust (Puccinia graminis f.Sp. tritici) through Variety and Nitrogen Fertilizer Application rate in West Shoa Zone","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-18 16:45:24","doi":"10.21203/rs.3.rs-7813373/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"92bb950e-bc5c-41a8-b58c-bb9e030027a4","owner":[],"postedDate":"December 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-14T05:39:50+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-18 16:45:24","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7813373","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7813373","identity":"rs-7813373","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}