Nanoparticles for the control of lettuce bacterial leaf spot (Xanthomonas hortorum pv. vitians)

Nanoparticles for the control of lettuce bacterial leaf spot (Xanthomonas hortorum pv. vitians) | 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 Nanoparticles for the control of lettuce bacterial leaf spot (Xanthomonas hortorum pv. vitians) Natalia Martins Freitas, Anielle Cristine Almeida Silva, Nilvanira Donizete Tebaldi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6066801/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 6 You are reading this latest preprint version Abstract Lettuce bacterial leaf spot, caused by Xanthomonas hortorum pv. vitians is one important pathogen of lettuce. The use of nanoparticles offers a new approach to controlling the disease. The objective of this work was to investigate the use of nanoparticles in the control of lettuce bacterial leaf spot and in seed treatment. Nanoparticles toxicity was evaluated by determining the in vitro bacterial growth inhibition zone. Lettuce seeds were inoculated with the bacteria and treated with CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles, the percentages of bacteria detected in the seeds, seed germination and seedlings emergence were determined. For the control of bacterial leaf spot, CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles were sprayed on lettuce plants in the preventive and curative application. In the preventive application, CuO, NiO, ZnO:1Ag, ZnOCl:5Ag, water and copper were sprayed, after three days, the plants were inoculated with a bacterial suspension (10 8 CFU/mL). In the curative application, the plants were inoculated with the bacteria, and three days later sprayed with the nanoparticles. Disease severity was assessed and the area under the disease progress curve was calculated. ZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO nanoparticles inhibited bacterial growth in vitro . CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles did not reduce the bacterium in inoculated lettuce seeds and did not reduce the seed germination and seedling emergence. The preventive and curative application of CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles reduced the lettuce bacterial leaf spot severity. The nanoparticles are alternative to manage lettuce bacterial leaf spot. Detection Germination Lactuca sativa Seeds Severity Introduction Lettuce bacterial leaf spot, caused by Xanthomonas hortorum pv. vitians (Xcv) (Morinière et al. 2020 ), may cause significant production losses, especially under high moisture conditions and temperatures between 23 and 28°C (Robinson et al. 2006 ). The disease has a worldwide distribution (Koike and Gilbertson 2017) and has been described in Brazil (Malavolta Júnior et al., 2008 ; Tebaldi et al. 2015 ). Lettuce bacterial leaf spot symptoms are soaked, translucent and brown lesions, which become black, and may coalesce and expand along the leaf vein, depreciating its quality (Tebaldi et al. 2015 ). The bacteria survive in crop debris, irrigation water, weeds and dry leaves in the soil (Toussaint et al. 2012 ; Fayette et al. 2018 ). The bacteria can be disseminated from plant to plant with the irrigation water in greenhouse (Wellman-Desbians 1999 ) and transmitted by infected seed (Umesh et al. 1996 ; Sahin and Miller1997). Bacterial leaf spot is thought to be seedborne, however, several attempts to re-isolate the bacteria from commercial lots were unsuccessful (Carisse et al. 2000 ) and the bacteria can be an external contaminant of lettuce seed (Koike and Gilbertson 2017). Contaminated seeds are considered an important source of lettuce bacterial leaf spot inoculum (Fayette et al. 2018 ). The pathogen can be introduced into lettuce fields via planting of contaminated seed for direct-seeded crops or via contaminated/infected transplants (Koike and Gilbertson 2017). Disease management includes prevention strategies, such as the use of pathogen-free seed, rotating crop, avoiding the use of sprinkler irrigation, removing crop debris and weeds (Koike and Gilbertson 2017). However, there is no registered chemical products for the lettuce bacterial leaf spot control and in seed treatment in Brazil, and nanoparticles can be an innovative strategy to disease control. The nanoparticles show high efficacy as biocides, due to their size, surface/volume ratio, and interaction with microorganism membranes (Allaker 2010 ). The use of nanoparticles reduced the severity of tomato bacteria spot caused by Xanthomonas hortorum pv. gardneri (Fraga et al 2021 , Oliveira et al 2023 , Santos et al. 2024 ), reduced the severity of bacterial leaf streak caused by Xanthomonas vasicola pv. vasculorum and white spot caused by Pantoea ananatis in maize (Mamede et al. 2022 , Mamede et al. 2024 ). However, the use of nanoparticles has not been evaluated for the control of lettuce bacterial leaf spot and for seed treatment. Therefore, the objective of this work was to evaluate the use of nanoparticles doped with different elements to inhibit bacterial growth in vitro ; to evaluate the efficiency of nanoparticles in seed treatment for the control of bacteria, and their effect on seed germination and seedling emergence of lettuce; and the efficacy of nanoparticles in preventive and curative applications for the control of lettuce bacterial leaf spot. Material and Methods The assays were conducted at Laboratório de Bacteriologia Vegetal (LABAC), Laboratório de Sementes (LASEM) and in greenhouse of the Instituto de Ciências Agrárias (ICIAG), Universidade Federal Uberlândia (UFU), Minas Gerais, Brazil. The nanoparticles approximate size was 20 nm were synthesized at Laboratório de Novos Materiais Nanoestruturados e Funcionais, Instituto de Física, Universidade Federal de Alagoas, according to the method described by Silva et al. ( 2018 ). The bacterial isolate UFU E125 of Xanthomonas hortorum pv. vitians , preserved and maintained in the work collection of the LABAC, was grown using the 523 medium (Kado and Heskett 1970 ) at 28 ºC. After 48 h, the bacterial suspension was prepared using sterile, filtered water and adjusted to OD 550 = 0.5 (10 9 CFU/mL) using a spectrophotometer. Nanoparticles to inhibit bacterial growth in vitro To evaluate the inhibition of bacterial growth in vitro were evaluated CuO, FeO, MnO, NiO, ZnO, and ZnOCl nanoparticles; ZnO nanoparticles doped with silver (Ag), gold (Au), calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), molybdenum (Mo), and nickel (Ni); and ZnOCl doped with silver (Ag) and copper (Cu) at different concentrations of the doping element (Table 1 ). The nanoparticles were prepared using filtered, sterile water at 10 mg/mL concentration, and then serially diluted (10 − 1 to 10 − 2 ). In Petri dishes (8 cm) was added a basic layer of 2% agar-water medium and semi-solid nutrient medium (0.8%), supplemented with 10% bacterial suspension (10 9 CFU/mL). Then, six sterile filter paper disks (6 mm) were placed onto the culture medium and soaked with 10 µL of each nanoparticle solution, water (negative control), and 500 µg/mL of cephalaxin (positive control). Each of the treatments had three replicates. After incubation at 28 ºC for 48 hours, the diameter (cm) of the inhibition zones were measured using a slide gauge. The experiment was repeated one time. The experiment was performed in a completely randomized design, in a factorial scheme, with 64 nanoparticles (pure, and doped nanoparticles at different concentrations), in serial dilutions (ND, 10 − 1 , 10 − 2 ), and 2 additional treatments (water and cephalaxin), with three replicates. The data obtained were submitted to analysis of variance and the means were compared using the Scott-Knott, with a P value of 0.05, and using the Dunnett test, in the R software (R Core Team 2020). Bacteria detection in inoculated seeds treated with nanoparticles Curly lettuce seeds cv. Vera were disinfected with 70% alcohol for 30 seconds, and then in a 1% sodium hypochlorite solution for 3 minutes. Then, the seeds were washed in sterilized filtered water and dried on sterile filter paper, under laminar flow. For seed inoculation, the bacterium was cultured in 523 culture medium at 28ºC for 48 hours. Then, 2.5 mL of sterile glycerol and 2.5 mL of 2.4% gelatin were added to the bacterial growth and homogenized using a Drigalski tool. Then, 100 seeds were placed on each plate for 10 minutes. The seeds were removed and placed on sterile filter paper to dry under laminar flow. In total, 2,500 seeds were inoculated. Inoculated seeds were treated for 10 minutes with ZnO:1.0Ag, ZnOCl:5.0Ag; CuO and NiO nanoparticles solutions at 2.5 mg/mL, and water (control), then dried on sterile filter paper under laminar flow. The nanoparticles were selected according to their ability to inhibit the bacterial growth in vitro. The experiment was repeated one time. To detect the bacteria in the seeds, 100 seeds of each treatment were divided into 4 replicates of 25 seeds, which were placed in a Petri dish containing culture medium 523 supplemented with cycloheximide (0.1 mg/mL) and incubated at 28 ºC for 48 hours. The percentage of seed contaminated with the bacterium was evaluated, with the presence of yellow and mucoid colonies. The test was performed in a completely randomized design, 4 + 2 (4 NPs + 2 additional [inoculated, uninoculated]), with 4 replicates. The data obtained were submitted to analysis of variance and the means were compared by Scott-Knott test, with a P value of 0.05 and by Dunnett test, using the R software (R Core Team 2020). The germination test was performed according to the standard procedures (Brasil, 2009), using 200 seeds for each treatment, with 4 replicates of 50 seeds. The seeds were placed onto two sheets of blotting paper in the plastic gerbox-types boxes (11x11x5cm), and the paper was soaked with water amount, equivalent to 2.5 times the paper dry mass. The seeds were taken to the germinator at 20 ºC and under 24-h photoperiod. The first and the final count germination was on the 4th and 7th day, the results were expressed in germination percentage. The test was performed in a completely randomized design, in a 2 x 4 + 1 factorial scheme (2 seed inoculation [inoculated or uninoculated], 4 NPs + 1 additional [water]), with 4 replicates. The data obtained were submitted to analysis of variance and the means were compared by Scott-Knott test, with a P value of 0.05 and by Dunnett test, using the R software (R Core Team 2020). For seed emergence test, 200 seeds for each treatment, with 4 replicates of 50 seeds were sown in a styrofoam tray (25 cm x 25 cm) containing sterile sand. After 9 days the emerged seedlings were counted. The experimental design was conducted in a randomized block, in a 2 x 4 + 1 factorial scheme (2 seed inoculation [inoculated or uninoculated], 4 NPs + 1 additional [water]), with 4 replications. The data obtained were submitted to analysis of variance and the means were compared by the Scott-Knott, with a P value of 0.05 and by the Dunnett test, using the R software (R Core Team 2020). Preventive and curative applications of nanoparticles to control bacterial leaf spot in lettuce Seedling of curly lettuce cv. Vera were grown in a green-house and transplanted, in 500-mL pots containing a mixture of sand, vermiculite and soil (1:1:3). Plants at the three- to four-leaf stage, for assessing preventive application were sprayed until runoff with the nanoparticle solution (ZnO:1.0Ag, ZnOCl:5.0Ag; CuO, and NiO) at 2.5 mg/mL concentration, commercial copper (2 mg/mL), and water. After 3 days, the plants were inoculated with bacterial suspension (10 8 CFU/mL). Similarly, the plants used for assessing the curative application were inoculated with bacterial suspension and, after 3 days, were sprayed with treatment solutions described above. The plants were kept in the most chamber for 24 h, before and after inoculation. Both experiments were performed at the same time. Commercial copper contains 35% metallic Cu in the form of copper hydroxide [Cu(OH) 2 ]. Commercial copper at 2 mg/mL contains Cu at approximately 0.7 mg/mL. Disease severity was assessed at 3, 6, 9, 12, and 15 days after inoculation using a diagrammatic scale (Mello et al. 1997). The area under the disease progress curve (AUDPC) was calculated using the following formula: AUDPC = ∑ [(Y i + Y i+1 )/2] (t i+1 – t i ), in which Y is disease intensity; t is time (interval between assessments, in days), and I is the number of assessments made over time (Shaner and Finney 1977 ). The experimental design was randomized block, in a 2 x 5 + 1 factorial scheme, with 2 applications (preventive and curative), 5 products (4 nanoparticles and copper, + 1 additional - water), and 5 replicates. The data obtained were subjected to an analysis of variance, and the means were compared using the Scott-Knott test, with a P value of 0.05, and by Dunnett test, in the R software (R Core Team 2020). The experiment was repeated twice. Results ZnO and ZnOCl nanoparticles doped with different concentrations of Ag and Au, inhibited bacterial growth under undiluted (10 mg/mL) and diluted 10 − 1 (1 mg/mL) solutions (Table 1 ). ZnO nanoparticles doped with different concentrations of Ag: 0.07, 0.3, 0.7, 1, 3, 7, 9 and 11; Au: 0.5, 1, 3 and 5; ZnOCl doped with Ag: 1, 5 and 10; CuO and NiO inhibited bacterial growth at undiluted (10 mg/mL) solutions. The largest inhibition zone occurred to ZnO:3.0Ag nanoparticles (1.8 cm), statistically similar with the cephalexin (positive control, antibiotic) (2.0 cm). The nanoparticles of ZnO:0.07Ag, ZnO:0.3Ag, ZnO:3.0Ag, ZnO:7.0Ag, ZnO:9.0Ag, ZnO:11.0Ag, ZnOCl:5.0Ag and ZnOCl:10.0Ag inhibited bacterial growth at 10 − 1 dilution (1 mg/mL). Only the nanoparticles ZnO:7.0Ag and ZnO:9.0 Ag inhibited bacterial growth at the 10 − 2 (0.1 mg/mL) dilution. Table 1 Growth inhibition zone (cm) for Xanthomonas hortorum pv. vitians , treated with undiluted (10 mg/mL) and diluted (10 − 1 , 10 − 2 ) nanoparticles. Nanoparticles Undiluted 10 − 1 10 − 2 CuO 1.06 dA*+ 0.00 eB* 0,00 bB* FeO 0.00 gA* 0.00 eA* 0.00 bA* MnO 0.00 gA* 0.00 eA* 0.00 bA* NiO 0.80 fA*+ 0.00 eB* 0,00 bB* ZnO 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.07Ag 1.10 dA*+ 0.83 dB*+ 0.00 bC* ZnO:0.3Ag 1.16 cA*+ 1,06 cA*+ 0.00 bB* ZnO:0.7Ag 1.20 cA*+ 0.00 eB* 0.00 bB* ZnO:1.0Ag 1.40 bA*+ 0.00 eB* 0.00 bB* ZnO:3.0Ag 1.80 aA + 1.43 aB*+ 0.00 bC* ZnO:7.0Ag 1.16 cA*+ 1.23 bA*+ 0.86 aB*+ ZnO:9.0Ag 1.03 dA*+ 1.00 cA*+ 0.86 aB*+ ZnO:11.0Ag 1.23 cA*+ 1.06 cB*+ 0.00 bC* ZnO:0.1Au 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.5Au 1.03 dA*+ 0.00 eB* 0.00 bB* ZnO:1.0Au 1.33 bA*+ 0.00 eB* 0.00 bB* ZnO:3.0Au 1.40 bA*+ 0.00 eB* 0.00 bB* ZnO:5.0Au 0.93 eA*+ 0.00 eB* 0.00 bB* ZnO:10.0Au 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.1Ca 0.00 gA* 0.00 eA* 0.00 bA* ZnO:1.0Ca 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.4Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnO:1.0Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnO:4.0Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnO:8.0Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnO:12.0Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.1Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.5Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:1.0Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:3.0Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:5.0Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:7.0Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:9.0Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:11.0Fe 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.5K 0.00 gA* 0.00 eA* 0.00 bA* ZnO:1.0K 0.00 gA* 0.00 eA* 0.00 bA* ZnO:10.0K 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.5Mg 0.00 gA* 0.00 eA* 0.00 bA* ZnO:1.0Mg 0.00 gA* 0.00 eA* 0.00 bA* ZnO:5.0Mg 0.00 gA* 0.00 eA* 0.00 bA* ZnO:10.0Mg 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.02Mn 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.4Mn 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.8Mn 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.2Mn 0.00 gA* 0.00 eA* 0.00 bA* ZnO:12.0Mn 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.5Mo 0.00 gA* 0.00 eA* 0.00 bA* ZnO:1.0Mo 0.00 gA* 0.00 eA* 0.00 bA* ZnO:5.0Mo 0.00 gA* 0.00 eA* 0.00 bA* ZnO:10.0Mo 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.3Ni 0.00 gA* 0.00 eA* 0.00 bA* ZnO:0.7Ni 0.00 gA* 0.00 eA* 0.00 bA* ZnO:1.0Ni 0.00 gA* 0.00 eA* 0.00 bA* ZnO:7.0Ni 0.00 gA* 0.00 eA* 0.00 bA* ZnO:11,0Ni 0.00 gA* 0.00 eA* 0.00 bA* ZnOCl (Sw) 0.00 gA* 0.00 eA* 0.00 bA* ZnOCl:0.1Ag 0,00 gA* 0,00 eA* 0.00 bA* ZnOCl:1.0Ag 0.80 fA*+ 0,00 eB* 0,00 bB* ZnOCl:5.0Ag 0.80 fA*+ 0.86 dA*+ 0,00 bB* ZnOCl:10.0Ag 0,90 eA*+ 0.93 dA*+ 0,00 bB* ZnOCl:0.1Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnOCl:1.0Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnOCl:5.0Cu 0.00 gA* 0.00 eA* 0.00 bA* ZnOCl:10.0Cu 0.00 gA* 0.00 eA* 0.00 bA* Water (negative control) 0.00 Cephalaxin (positive control) 2.00 CuO (copper oxide), FeO (iron oxide), MnO (manganese oxide), NiO (nickel oxide), ZnO: (zinco oxide) doped with: Ag (silver), Au (gold), Ca (calcium), Cu (copper), Fe (iron), K (potassium), Mg (magnesium), Mn (manganese), Mo (molybdonium), Ni (nickel), ZnOCl (monohydrated zinc chloretum hydroxide or Simonkolleite) doped with: Ag (silver) and Cu (copper). Means followed by different uppercase letters in the row and lowercase letters in the column are significantly different, as determined using Scott-Knott test ( P = 0.05) *Differs by Dunnett's test when compared to cephalaxin (positive control) at 5%. +Differs by Dunnett's test when compared to water (negative control) at 5%. The pure ZnO and ZnOCl nanoparticles, ZnO doped with Ca, Cu, Fe, K, Mg, Mn, Mo, and Ni; ZnOCl doped with Cu; FeO, MnO and NiO nanoparticles, as well the water (negative control) did not inhibit bacterial growth. The bacterium was detected in 100% of the untreated inoculated seeds (water – positive control) (Table 2 ), not differing significantly from the inoculated seeds treated with CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles, ranging from 88 to 98%. No bacteria were detected in uninoculated seeds. Table 2 Detection of Xanthomonas hortorum pv. vitians in inoculated lettuce seeds and treated with different nanoparticles. Treatments Detection (%) CuO 88 a* NiO 98 a ZnO:1.0Ag 95 a ZnOCl:5.0Ag 96 a Water (inoculated, positive control) 100 a Water (uninoculated, negative control) 0.0 b CV (%) 8.07 Means followed by different lowercase letters in the column differ significantly, according to the Scott-Knott test (P = 0.05). *Differs by Dunnett's test when compared to water (uninoculated, negative control) at 5%. The germination and emergence percentage (Table 3 ) of lettuce seeds inoculated and treated with CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles did not differ significantly of the control (water), range from 99 to 100%, and 66 to 81%, respectively. Only NiO (93%) nanoparticle reduced the seed germination and seedling emergence. For uninoculated seeds, ZnOCl:5Ag reduced the seed germination (88%), differing from the other treatments. The germination percentage of inoculated and uninoculated seeds did not differ statistically when treated with CuO and NiO. The emergence percentage of inoculated seeds increased when treated with CuO, ZnO:1.0Ag and ZnOCl:5.0Ag compared with uninoculated seed. Table 3 Germination and emergence percentage of inoculated lettuce seeds, with Xanthomonas hortorum pv. vitians and treated with different nanoparticles. Germination (%) Emergence (%) Treatments Inoculated Uninoculated Inoculated Uninoculated CuO 100 aA 96 aA 70 aA 50 bB NiO 93 bA* 95 aA* 44 bB 64 aA ZnO:1.0Ag 100 aA 95 aB 66 aA 32 cB* ZnOCl:5.0Ag 99 aA* 88 bB* 81 aA 28 cB* Water (control) 100 a 100 a 58 a 48 a CV (% 3.10 17.06 Means followed by different lowercase letters in the column and uppercase letters in the row differ significantly according to the Scott-Knott test (P = 0.05) *Differs by Dunnett's test when compared to water (negative control) at 5%. The area under the disease progress curve (AUDPC), for lettuce bacterial leaf spot, using different nanoparticles showed no significant difference between the preventive and curative applications (Table 4 ). In the preventive application, CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles, and copper (30.6) significantly reduced the disease severity when compared to the water-untread control (252.9). In the preventive application, all treatments reduced the progress curve of lettuce bacterial leaf spot compared to the untreated control, reducing the disease severity. In the curative application, CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles, and copper significantly reduced the lettuce bacterial leaf spot severity. Table 4 Area under the disease progress curve for lettuce bacterial leaf spot, using different nanoparticles in preventive and curative application. Application Preventive Curative CuO 54.6 aA* 68.4 aA* NiO 64.2 aA 205.2 bB ZnO:1.0Ag 69.0 aA* 76.8 aA* ZnOCl:5.0Ag 34.8 aA* 71.4 aA* Copper 30.6 aA* 107.4 aB* Water (control) 252.9 b 249.9 b Media 84.4 A 129.9 A CV (%) 44.61 Means followed by lowercase letters in the column and uppercase letters in the row are significantly different, by the Scott-Knott test (P = 0.05). *Differs by Dunnett's test when compared to water (positive control) at 5%. Discussion This study showed the nanoparticles bactericidal potential of ZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO, to inhibit the bacterial growth of Xanthomonas hortorum pv. vitians . Similar results were observed in the growth inhibition of Xanthomonas hortorum pv. gardneri (Fraga et al. 2021 , Oliveira et al. 2023 ), Pantoea ananatis , Dickeya zeae , and Xanthomonas vasicola pv. vasculorum (Mamede et al. 2022 ; Mamede et al. 2024 ), using the same nanoparticles. Thus, the ZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO nanoparticles showed significant antibacterial property and can be used to bacterial control. ZnO:Ag, ZnO:Au, ZnOCl:Ag nanoparticles at 10 and 1 mg/mL concentrations, and CuO, and NiO nanoparticles at 10 mg/mL inhibited the growth of Xanthomonas hortorum pv. vitians. Only the ZnO and ZnOCl nanoparticles doped with gold (Au) and silver (Ag) (ZnO:Ag, ZnO:Au, ZnOCl:Ag) inhibited the bacterial growth showing the antibacterial activity. The silver ions antibacterial mechanism is due the, DNA losses its replication ability (Feng et al 2000 ), resulting in the ribossomal inactivation and in ATP production (Yamanaka et al. 2005 ). FeO, MnO, ZnO, ZnO:Ca, ZnO:Cu, ZnO:Fe, ZnO:K, ZnO:Mg, ZnO:Mn, ZnO:Mo, ZnO:Ni, ZnOCl, and ZnOCl:Cu nanoparticles did not inhibit bacterial growth. This indicates that the isolate UFU E125 of Xanthomonas hortorum pv. vitians is not sensitive to those nanoparticles. In this study the nanoparticles did not reduce the bacteria in inoculated lettuce seed, maybe due to the methodology used to inoculate the seeds, using glycerol and gelatin onto bacterial growth in Petri dishes. The seeds became completely involve with the bacteria and the nanoparticles were not enough to control them, other essays of lettuce seeds inoculation must be carried out to assess the inoculation efficacy for the control the bacteria. Pathogen-free seeds has become an important strategy for bacterial control, and nanoparticles have been shown promise in seed treatment for the control of Xanthomonas hortorum pv. gardneri in tomato seeds (Fraga et al., 2021 , Oliveira et al. 2023 ) and Alternaria alternata in wheat seeds (Duarte et al. 2022 ). In this study nanoparticles did not inhibit the seed germination and seedlings emergence of lettuce, as well as the seed of corn (Pokhrel and Dubey 2013 ), wheat (Feizi et al. 2013 ), tomato (Siddiqui and Al-Whaibi 2014 ; Fraga et al. 2021 , Oliveira et al. 2023 ), corn (Segatto et al. 2018 ), and cucumber (De La Rosa et al. 2013 ) treated with nanoparticles there was no reduction in the seed germination. Although the AUDPC for lettuce bacterial leaf spot using different nanoparticles did not differ in preventive and curative application, the preventive application showed less disease severity, possibly due to the formation of a protective barrier created by the nanoparticles in the leaf tissue, before inoculation, making it difficult for the bacteria to penetrate. Preventive application of ZnO nanoparticles to control bacterial speck caused by Pseudomonas syringae pv. tomato induced the defense mechanism of tomato plants, showing higher self-defense enzyme activity (Elsharkawy et al. 2020 ). Also, the preventive application of nanoparticles of ZnO:0.5Mo, ZnO:1K, and ZnO:1Mg reduce the tomato bacterial spot (Fraga et al. 2020). In this study, CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles reduced disease severity and showed potential for use in the management of lettuce bacterial leaf spot, since there are no products registered to control the disease in Brazil. Bacterial diseases are difficult to control, especially when already established in the field, and preventive measures are considered the most important approaches to avoid initial infection, and the use of nanoparticles can reduce lettuce bacterial leaf spot severity. Nanoparticles have shown beneficial effects in plants, activating defense mechanisms and micronutrient uptake (Cartwright et al. 2020 ). ZnO nanoparticles can interact with the bacterial surface or core, exhibiting distinct bactericidal mechanisms: altering the viscosity and structure of the cell membrane, increasing its permeability (Hou et al. 2018 ; Siddiqi et al. 2018 ), damaging the cell wall and allowing toxic compounds to enter the cytoplasm (Czyżowska and Barbasz, 2020 ), and inducing resistance in plants, protecting against the pathogens (Elsharkawy et al. 2020 ). ZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO nanoparticles inhibited the bacterial growth of Xanthomonas hortorum pv. vitians in vitro . CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles did not reduce the bacterium in inoculated lettuce seeds, and did not reduce the seed germination and seedling emergence. The preventive and curative application of CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag reduced the bacterial leaf spot severity. The nanoparticles showed promising to manage bacterial leaf spot in lettuce. Declarations Conflict of interest The authors declare no conflicts of interest. Funding CAPES and CNPq Author contribution NMF performed material preparation, data collection, analysis, and manuscript writing. NDT contributed to the study’s conception and design, and to the manuscript’s writing and revision. ACAS synthesized the nanocrystals. All authors approved the final manuscript. Acknowledgements The authors thank CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Brazil), and CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil) for providing a scholarship to NMF, and to NDT (Research Productivity, Grant 302875/2022-0), respectively, and are grateful to Lara Caroline Borges Moreira for her contribution to data collection. Data availability The authors declare that the data supporting the findings of this study are available upon request. References Allaker RP (2010) The use of nanoparticles to control oral biofilm formation. J Dent Res 89:1175–1186 Carisse O, Ouimet A, Toussaint V, Philion V (2000) Evaluation of the effect of seed treatments, bactericides, and cultivars on bacterial leaf spot of lettuce caused by Xanthomonas campestris pv. vitians . Plant Disease 84:295–299 Cartwright A, Jackson K, Morgan C, Anderson A, Britt DW (2020) A review of metal and metal-oxide nanoparticle coating technologies to inhibit agglomeration and increase bioactivity for agricultural applications. Agronomy 10:1018 Czyżowska A, Barbasz A (2020) A review: zinc oxide nanoparticles friends or enemies? Int J Environ Health Res 32:885–901 De La Rosa G, López-Moreno ML, Haro D, Botez CE, Peralta-Videa JR, Gardea-Torresdey JL (2013) Effects of ZnO nanoparticles in alfalfa, tomato, and cucumber at the germination stage: Root development and X-ray absorption spectroscopy studies. Pure Appl Chem 85:2161–2174 Duarte LC, Catão HCRM, Tebaldi ND (2022) Nanoparticles and photodynamic therapy in the treatment and control of Alternaria alternata in wheat seeds. Ciência e Agrotecologia 46:e005222 Elsharkawy M, Derbalah A, Hamza A, El-Shaer A (2020) Zinc oxide nanostructures as a control strategy of bacterial speck of tomato caused by Pseudomonas syringae in Egypt. Environ Sci Pollut Res 27:19049–19057 Fayette J, Jones JB, Pernezny K, Roberts PD, Raid R (2018) Survival of Xanthomonas campestris pv. vitians on lettuce in crop debris, irrigation water, and weeds in south Florida. Eur J Plant Pathol 151:341–353 Feizi H, Moghaddam PR, Shahtahmassebi N, Fotovat A (2013) Assessment of concentrations of nano and bulk iron oxide particles on early growth of wheat ( Triticum aestivum L). Annual Rev Res Biology 3:752–761 Feng QL, Wu J, Chen GQ, Cui FZ, Kim TN, Kim JO (2000) A mechanistic study of the antibacterial effect of silver ions on Escherichia coli and Staphylococcus aureus . J Biomed Mater Res 52:662–668 Fraga FS, Silva ACA, Dantas NO, Tebaldi ND, Luz JMQ (2021) Doped zinc-oxide nanocrystals for the control of tomato bacterial spot and Xanthomonas gardneri in seeds. Trop Plant Pathol 46:406–413 Hou J, Wu Y, Li X, Wei B, Li S, Wang X (2018) Toxic effects of different types of zinc oxide nanoparticles on algae, plants, invertebrates, vertebrates and microorganisms. Chemosphere 193:852–860 Kado CI, Heskett MG (1970) Selective media for isolation of Agrobacterium, Corynebacterium , Erwinia , Pseudomonas , and Xanthomonas . Phytopathology 60:969 – 76 Koide ST, Gilbertson RL (2017) Detection of Xanthomonas campestris pv. vitians in lettuce seeds. In: Fatmi MB, Walcott RR, Schaad NW (eds) Detection of plant-pathogenic bacteria in seed and other planting material. APS, St. Paul., pp 173–178 Malavolta Júnior VA, Beriam LOS, Almeida IMG, Rodrigues Neto J, Robbs CF (2008) Bactérias fitopatogênicas assinaladas no Brasil: Uma atualização. Summa Phytopathologica 34S:9–87 Mamede MC, Mota RP, Silva ACA, Tebaldi ND (2022) Nanoparticles in inhibiting Pantoea ananatis and control maize white spot. Ciência Rural 52:e20210481 Mamede MC, Silva ACA, Tebaldi ND (2024) Dickeya zeae, Pantoea ananatis , and Xanthomonas vasicola pv. vasculorum : control with the use of nanoparticles. Ciência e Agrotecnologia 48:e018423 Morinière L, Burlet A, Rosenthal ER, Nesme X, Portier P, Bull CT, Lavire C, Fischer-Le Saux M, Bertolla F (2020) Clarifying the taxonomy of the causal agent of bacterial leaf spot of lettuce through a polyphasic approach reveals that Xanthomonas cynarae Trébaol 2000 emend. Timilsina 2019 is a later heterotypic synonym of Xanthomonas hortorum Vauterin 1995. Systematic and Applied Microbiology 43:126087 Oliveira NS, Silva ACA, Tebaldi ND (2023) Simonkolleite nanoparticles for seed treatment and control of tomato bacterial spot caused by Xanthomonas hortorum pv. gardneri . Ciência e Agrotecnologia 47:e000623 Pokhrel LR, Dubey B (2013) Evaluation of developmental responses of two crop plants exposed to silver and zinc oxide nanoparticles. Sci Total Environ 452–453:321–332 R Core Team (2023) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria Robinson PE, Jones JB, Pernezny K (2006) Bacterial leaf spot of lettuce: Relationship of temperature to infection and potential host range of Xanthomonas campestris pv. vitians . Plant Disease 90:465–470 Sahin F, Miller SA (1997) Identification of the bacterial leaf spot pathogen of lettuce, Xanthomonas campestris pv. vitians , in Ohio, and assessment of cultivar resistance and seed treatment. Plant Disease 81:1443–1446 Santos LCM, Silva ACA, Tebaldi ND (2024) Nanocrystals spraying interval for the control of tomato bacterial spot caused by Xanthomonas hortorum pv. gardneri . Revista Ceres 71:e71018 Segatto C, Ternus R, Junges M, Mello JMM, Luz GL, Riella HG, Silva LL, Lajús CR, Fiori MA (2018) Adsorption and incorporation of the zinc oxide nanoparticles in seeds of corn: germination performance and antimicrobial protection. Int J Adv Eng Res Sci 5:2456–6495 Shaner G, Finney RE (1977) The effect of nitrogen fertilization on the expression of slow-mildewing resistance in Knox wheat. Phytopathology 66:1051–1056 Siddiqi KS, Husen A, Rao RAK (2018) A review on biosynthesis of silver nanoparticles and their biocidal properties. J Nanobiotechnol 16:14 Siddiqui MH, Al-Whaibi H (2014) Role of nano-SiO 2 in germination of tomato ( Lycopersicum esculentum seeds Mill). Saudi J Bioligical Sci 21:13–17 Silva ACA, Zóia MAP, Correia LIV, Azevedo FVPV, Paula AT, Maia LP, Carvalho LS, Carvalho LN, Costa MPC, Giaretta LC, Rodrigues RS, Ávila VM, Goulart LR, Dantas NO (2018) In: Celik TA (ed) Biocompatibility of doped semiconductors nanocrystals and nanocomposites. Cytotoxicity, InTech, pp 149–161 Tebaldi ND, Martins OM, Mota LCBM (2015) Ocorrência de Xanthomonas campestris pv. vitians em alface, em Minas Gerais. Summa Phytopathologica 41:321 Toussaint V, Benoit DL, Carisse O (2012) Potential of weed species to serve as a reservoir for Xanthomonas campestris pv. vitians , the causal agent of bacterial leaf spot of lettuce. Crop Prot 41:64–70 Umesh KC, Koike ST, Gilbertson RL (1996) Association of Xanthomonas campestris pv. vitians with lettuce seed. Phytopathology 86:S3 Wellman-Desbians E (1999) Dissemination of Xanthomonas campestris pv. vitians during lettuce transplant production. Phytopathology 89:S84 Yamanaka M, Hara K, Kudo J (2005) Bactericidal actions of a silver ion solution on Escherichia coli , studied by energy-filtering transmission electron microscopy and proteomic analysis. Appl Environ Microbiol 71:7589–7593 Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 10 Mar, 2025 Reviewers invited by journal 07 Mar, 2025 Editor invited by journal 05 Mar, 2025 Editor assigned by journal 04 Mar, 2025 First submitted to journal 28 Feb, 2025 Editorial decision: Major revisions 28 Feb, 2025 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-6066801","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":425541408,"identity":"b143f7ef-26e9-4d00-aa7e-cdaf45d4367f","order_by":0,"name":"Natalia Martins Freitas","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Natalia","middleName":"Martins","lastName":"Freitas","suffix":""},{"id":425541409,"identity":"80b83d31-5dfa-4f06-adb0-247618c9c683","order_by":1,"name":"Anielle Cristine Almeida Silva","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Anielle","middleName":"Cristine Almeida","lastName":"Silva","suffix":""},{"id":425541410,"identity":"4517f032-7ca8-44b3-b687-72e02c9ca2d3","order_by":2,"name":"Nilvanira Donizete Tebaldi","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABAUlEQVRIie3PsUoDMRzH8X/4Q2+JdP0fx+kr5LihPfBh7OIktG4OIjkO0snOJwg+g5tjSkCXgi/QRQ46VRAEQUQxaSnFIWfHDvkOIcsnPwIQCu1jiNKetL4D9JmKJLwB6BbCNgQdIaa4ZnUrgRWBLZF00k56EVP0+dAfdmV32owuKZ3Ey6ziMB/6SFExFV/PqKg1Yl4/Uq6SM0cWhfQQYVglDhQJ0NhJeIcGlvQaDkb4VhzJvi050hh98R9L4plbaSVl41aEXUF7GSjiO5DUksxgntxM7F/46Xl5KxZ+8mz09FVdicOn8uV99HGc3o3NvVxezL1kG/596n8QCoVCIX+/s1hQWGb5mhcAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0001-6983-9718","institution":"Universidade Federal de Uberlândia","correspondingAuthor":true,"prefix":"","firstName":"Nilvanira","middleName":"Donizete","lastName":"Tebaldi","suffix":""}],"badges":[],"createdAt":"2025-02-19 20:20:37","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6066801/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6066801/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":78257836,"identity":"bc479c2f-f62c-48c0-bca0-7fa54320948e","added_by":"auto","created_at":"2025-03-11 11:07:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":768938,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6066801/v1/1b32e8be-665f-47f5-92d1-8454aa6a4df1.pdf"}],"financialInterests":"","formattedTitle":"Nanoparticles for the control of lettuce bacterial leaf spot (Xanthomonas hortorum pv. vitians)","fulltext":[{"header":"Introduction","content":"\u003cp\u003eLettuce bacterial leaf spot, caused by \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e (Xcv) (Morini\u0026egrave;re et al. \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), may cause significant production losses, especially under high moisture conditions and temperatures between 23 and 28\u0026deg;C (Robinson et al. \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). The disease has a worldwide distribution (Koike and Gilbertson 2017) and has been described in Brazil (Malavolta J\u0026uacute;nior et al., \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2008\u003c/span\u003e; Tebaldi et al. \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2015\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eLettuce bacterial leaf spot symptoms are soaked, translucent and brown lesions, which become black, and may coalesce and expand along the leaf vein, depreciating its quality (Tebaldi et al. \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). The bacteria survive in crop debris, irrigation water, weeds and dry leaves in the soil (Toussaint et al. \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2012\u003c/span\u003e; Fayette et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). The bacteria can be disseminated from plant to plant with the irrigation water in greenhouse (Wellman-Desbians \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e1999\u003c/span\u003e) and transmitted by infected seed (Umesh et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e1996\u003c/span\u003e; Sahin and Miller1997). Bacterial leaf spot is thought to be seedborne, however, several attempts to re-isolate the bacteria from commercial lots were unsuccessful (Carisse et al. \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2000\u003c/span\u003e) and the bacteria can be an external contaminant of lettuce seed (Koike and Gilbertson 2017). Contaminated seeds are considered an important source of lettuce bacterial leaf spot inoculum (Fayette et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). The pathogen can be introduced into lettuce fields via planting of contaminated seed for direct-seeded crops or via contaminated/infected transplants (Koike and Gilbertson 2017).\u003c/p\u003e \u003cp\u003eDisease management includes prevention strategies, such as the use of pathogen-free seed, rotating crop, avoiding the use of sprinkler irrigation, removing crop debris and weeds (Koike and Gilbertson 2017). However, there is no registered chemical products for the lettuce bacterial leaf spot control and in seed treatment in Brazil, and nanoparticles can be an innovative strategy to disease control.\u003c/p\u003e \u003cp\u003eThe nanoparticles show high efficacy as biocides, due to their size, surface/volume ratio, and interaction with microorganism membranes (Allaker \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2010\u003c/span\u003e). The use of nanoparticles reduced the severity of tomato bacteria spot caused by \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003egardneri\u003c/em\u003e (Fraga et al \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, Oliveira et al \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2023\u003c/span\u003e, Santos et al. \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), reduced the severity of bacterial leaf streak caused by \u003cem\u003eXanthomonas vasicola\u003c/em\u003e pv. \u003cem\u003evasculorum\u003c/em\u003e and white spot caused by \u003cem\u003ePantoea ananatis\u003c/em\u003e in maize (Mamede et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2022\u003c/span\u003e, Mamede et al. \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). However, the use of nanoparticles has not been evaluated for the control of lettuce bacterial leaf spot and for seed treatment.\u003c/p\u003e \u003cp\u003eTherefore, the objective of this work was to evaluate the use of nanoparticles doped with different elements to inhibit bacterial growth \u003cem\u003ein vitro\u003c/em\u003e; to evaluate the efficiency of nanoparticles in seed treatment for the control of bacteria, and their effect on seed germination and seedling emergence of lettuce; and the efficacy of nanoparticles in preventive and curative applications for the control of lettuce bacterial leaf spot.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cp\u003eThe assays were conducted at Laborat\u0026oacute;rio de Bacteriologia Vegetal (LABAC), Laborat\u0026oacute;rio de Sementes (LASEM) and in greenhouse of the Instituto de Ci\u0026ecirc;ncias Agr\u0026aacute;rias (ICIAG), Universidade Federal Uberl\u0026acirc;ndia (UFU), Minas Gerais, Brazil. The nanoparticles approximate size was 20 nm were synthesized at Laborat\u0026oacute;rio de Novos Materiais Nanoestruturados e Funcionais, Instituto de F\u0026iacute;sica, Universidade Federal de Alagoas, according to the method described by Silva et al. (\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2018\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe bacterial isolate UFU E125 of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e, preserved and maintained in the work collection of the LABAC, was grown using the 523 medium (Kado and Heskett \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e1970\u003c/span\u003e) at 28 \u0026ordm;C. After 48 h, the bacterial suspension was prepared using sterile, filtered water and adjusted to OD\u003csub\u003e550\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;0.5 (10\u003csup\u003e9\u003c/sup\u003e CFU/mL) using a spectrophotometer.\u003c/p\u003e \u003cp\u003e \u003cb\u003eNanoparticles to inhibit bacterial growth\u003c/b\u003e \u003cb\u003ein vitro\u003c/b\u003e\u003c/p\u003e \u003cp\u003eTo evaluate the inhibition of bacterial growth \u003cem\u003ein vitro\u003c/em\u003e were evaluated CuO, FeO, MnO, NiO, ZnO, and ZnOCl nanoparticles; ZnO nanoparticles doped with silver (Ag), gold (Au), calcium (Ca), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), molybdenum (Mo), and nickel (Ni); and ZnOCl doped with silver (Ag) and copper (Cu) at different concentrations of the doping element (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The nanoparticles were prepared using filtered, sterile water at 10 mg/mL concentration, and then serially diluted (10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e to 10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e).\u003c/p\u003e \u003cp\u003eIn Petri dishes (8 cm) was added a basic layer of 2% agar-water medium and semi-solid nutrient medium (0.8%), supplemented with 10% bacterial suspension (10\u003csup\u003e9\u003c/sup\u003e CFU/mL). Then, six sterile filter paper disks (6 mm) were placed onto the culture medium and soaked with 10 \u0026micro;L of each nanoparticle solution, water (negative control), and 500 \u0026micro;g/mL of cephalaxin (positive control). Each of the treatments had three replicates. After incubation at 28 \u0026ordm;C for 48 hours, the diameter (cm) of the inhibition zones were measured using a slide gauge. The experiment was repeated one time.\u003c/p\u003e \u003cp\u003eThe experiment was performed in a completely randomized design, in a factorial scheme, with 64 nanoparticles (pure, and doped nanoparticles at different concentrations), in serial dilutions (ND, 10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e), and 2 additional treatments (water and cephalaxin), with three replicates. The data obtained were submitted to analysis of variance and the means were compared using the Scott-Knott, with a \u003cem\u003eP\u003c/em\u003e value of 0.05, and using the Dunnett test, in the R software (R Core Team 2020).\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eBacteria detection in inoculated seeds treated with nanoparticles\u003c/h2\u003e \u003cp\u003eCurly lettuce seeds cv. Vera were disinfected with 70% alcohol for 30 seconds, and then in a 1% sodium hypochlorite solution for 3 minutes. Then, the seeds were washed in sterilized filtered water and dried on sterile filter paper, under laminar flow.\u003c/p\u003e \u003cp\u003eFor seed inoculation, the bacterium was cultured in 523 culture medium at 28\u0026ordm;C for 48 hours. Then, 2.5 mL of sterile glycerol and 2.5 mL of 2.4% gelatin were added to the bacterial growth and homogenized using a Drigalski tool. Then, 100 seeds were placed on each plate for 10 minutes. The seeds were removed and placed on sterile filter paper to dry under laminar flow. In total, 2,500 seeds were inoculated.\u003c/p\u003e \u003cp\u003eInoculated seeds were treated for 10 minutes with ZnO:1.0Ag, ZnOCl:5.0Ag; CuO and NiO nanoparticles solutions at 2.5 mg/mL, and water (control), then dried on sterile filter paper under laminar flow. The nanoparticles were selected according to their ability to inhibit the bacterial growth \u003cem\u003ein vitro.\u003c/em\u003e The experiment was repeated one time.\u003c/p\u003e \u003cp\u003eTo detect the bacteria in the seeds, 100 seeds of each treatment were divided into 4 replicates of 25 seeds, which were placed in a Petri dish containing culture medium 523 supplemented with cycloheximide (0.1 mg/mL) and incubated at 28 \u0026ordm;C for 48 hours. The percentage of seed contaminated with the bacterium was evaluated, with the presence of yellow and mucoid colonies. The test was performed in a completely randomized design, 4\u0026thinsp;+\u0026thinsp;2 (4 NPs\u0026thinsp;+\u0026thinsp;2 additional [inoculated, uninoculated]), with 4 replicates. The data obtained were submitted to analysis of variance and the means were compared by Scott-Knott test, with a \u003cem\u003eP\u003c/em\u003e value of 0.05 and by Dunnett test, using the R software (R Core Team 2020).\u003c/p\u003e \u003cp\u003eThe germination test was performed according to the standard procedures (Brasil, 2009), using 200 seeds for each treatment, with 4 replicates of 50 seeds. The seeds were placed onto two sheets of blotting paper in the plastic gerbox-types boxes (11x11x5cm), and the paper was soaked with water amount, equivalent to 2.5 times the paper dry mass. The seeds were taken to the germinator at 20 \u0026ordm;C and under 24-h photoperiod. The first and the final count germination was on the 4th and 7th day, the results were expressed in germination percentage. The test was performed in a completely randomized design, in a 2 x 4\u0026thinsp;+\u0026thinsp;1 factorial scheme (2 seed inoculation [inoculated or uninoculated], 4 NPs\u0026thinsp;+\u0026thinsp;1 additional [water]), with 4 replicates. The data obtained were submitted to analysis of variance and the means were compared by Scott-Knott test, with a \u003cem\u003eP\u003c/em\u003e value of 0.05 and by Dunnett test, using the R software (R Core Team 2020).\u003c/p\u003e \u003cp\u003eFor seed emergence test, 200 seeds for each treatment, with 4 replicates of 50 seeds were sown in a styrofoam tray (25 cm x 25 cm) containing sterile sand. After 9 days the emerged seedlings were counted. The experimental design was conducted in a randomized block, in a 2 x 4\u0026thinsp;+\u0026thinsp;1 factorial scheme (2 seed inoculation [inoculated or uninoculated], 4 NPs\u0026thinsp;+\u0026thinsp;1 additional [water]), with 4 replications. The data obtained were submitted to analysis of variance and the means were compared by the Scott-Knott, with a \u003cem\u003eP\u003c/em\u003e value of 0.05 and by the Dunnett test, using the R software (R Core Team 2020).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003ePreventive and curative applications of nanoparticles to control bacterial leaf spot in lettuce\u003c/h3\u003e\n\u003cp\u003eSeedling of curly lettuce cv. Vera were grown in a green-house and transplanted, in 500-mL pots containing a mixture of sand, vermiculite and soil (1:1:3). Plants at the three- to four-leaf stage, for assessing preventive application were sprayed until runoff with the nanoparticle solution (ZnO:1.0Ag, ZnOCl:5.0Ag; CuO, and NiO) at 2.5 mg/mL concentration, commercial copper (2 mg/mL), and water. After 3 days, the plants were inoculated with bacterial suspension (10\u003csup\u003e8\u003c/sup\u003e CFU/mL). Similarly, the plants used for assessing the curative application were inoculated with bacterial suspension and, after 3 days, were sprayed with treatment solutions described above. The plants were kept in the most chamber for 24 h, before and after inoculation. Both experiments were performed at the same time. Commercial copper contains 35% metallic Cu in the form of copper hydroxide [Cu(OH)\u003csub\u003e2\u003c/sub\u003e]. Commercial copper at 2 mg/mL contains Cu at approximately 0.7 mg/mL.\u003c/p\u003e \u003cp\u003eDisease severity was assessed at 3, 6, 9, 12, and 15 days after inoculation using a diagrammatic scale (Mello et al. 1997). The area under the disease progress curve (AUDPC) was calculated using the following formula: AUDPC = \u0026sum; [(Y\u003csub\u003ei\u003c/sub\u003e + Y\u003csub\u003ei+1\u003c/sub\u003e)/2] (t\u003csub\u003ei+1\u003c/sub\u003e \u0026ndash; t\u003csub\u003ei\u003c/sub\u003e), in which Y is disease intensity; t is time (interval between assessments, in days), and I is the number of assessments made over time (Shaner and Finney \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e1977\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eThe experimental design was randomized block, in a 2 x 5\u0026thinsp;+\u0026thinsp;1 factorial scheme, with 2 applications (preventive and curative), 5 products (4 nanoparticles and copper, + 1 additional - water), and 5 replicates. The data obtained were subjected to an analysis of variance, and the means were compared using the Scott-Knott test, with a \u003cem\u003eP\u003c/em\u003e value of 0.05, and by Dunnett test, in the R software (R Core Team 2020). The experiment was repeated twice.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eZnO and ZnOCl nanoparticles doped with different concentrations of Ag and Au, inhibited bacterial growth under undiluted (10 mg/mL) and diluted 10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e (1 mg/mL) solutions (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). ZnO nanoparticles doped with different concentrations of Ag: 0.07, 0.3, 0.7, 1, 3, 7, 9 and 11; Au: 0.5, 1, 3 and 5; ZnOCl doped with Ag: 1, 5 and 10; CuO and NiO inhibited bacterial growth at undiluted (10 mg/mL) solutions. The largest inhibition zone occurred to ZnO:3.0Ag nanoparticles (1.8 cm), statistically similar with the cephalexin (positive control, antibiotic) (2.0 cm). The nanoparticles of ZnO:0.07Ag, ZnO:0.3Ag, ZnO:3.0Ag, ZnO:7.0Ag, ZnO:9.0Ag, ZnO:11.0Ag, ZnOCl:5.0Ag and ZnOCl:10.0Ag inhibited bacterial growth at 10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e dilution (1 mg/mL). Only the nanoparticles ZnO:7.0Ag and ZnO:9.0 Ag inhibited bacterial growth at the 10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e (0.1 mg/mL) dilution.\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\u003eGrowth inhibition zone (cm) for \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e, treated with undiluted (10 mg/mL) and diluted (10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e) nanoparticles.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNanoparticles\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eUndiluted\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e10\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCuO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.06 dA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFeO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMnO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.80 fA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.07Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.10 dA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.83 dB*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bC*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.3Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.16 cA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1,06 cA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.7Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.20 cA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.40 bA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:3.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.80 aA +\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.43 aB*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bC*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:7.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.16 cA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.23 bA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.86 aB*+\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:9.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.03 dA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.00 cA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.86 aB*+\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:11.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.23 cA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.06 cB*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bC*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.1Au\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.5Au\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.03 dA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Au\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.33 bA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:3.0Au\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.40 bA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:5.0Au\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.93 eA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:10.0Au\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.1Ca\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Ca\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.4Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:4.0Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:8.0Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:12.0Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.1Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.5Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:3.0Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:5.0Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:7.0Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:9.0Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:11.0Fe\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.5K\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0K\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:10.0K\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.5Mg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Mg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:5.0Mg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:10.0Mg\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.02Mn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.4Mn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.8Mn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.2Mn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:12.0Mn\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.5Mo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Mo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:5.0Mo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:10.0Mo\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.3Ni\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:0.7Ni\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Ni\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:7.0Ni\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:11,0Ni\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl (Sw)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:0.1Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:1.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.80 fA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0,00 eB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:5.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.80 fA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.86 dA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:10.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0,90 eA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.93 dA*+\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0,00 bB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:0.1Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:1.0Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:5.0Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:10.0Cu\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.00 gA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00 eA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.00 bA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWater (negative control)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCephalaxin (positive control)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eCuO (copper oxide), FeO (iron oxide), MnO (manganese oxide), NiO (nickel oxide), ZnO: (zinco oxide) doped with: Ag (silver), Au (gold), Ca (calcium), Cu (copper), Fe (iron), K (potassium), Mg (magnesium), Mn (manganese), Mo (molybdonium), Ni (nickel), ZnOCl (monohydrated zinc chloretum hydroxide or Simonkolleite) doped with: Ag (silver) and Cu (copper).\u003c/p\u003e \u003cp\u003eMeans followed by different uppercase letters in the row and lowercase letters in the column are significantly different, as determined using Scott-Knott test (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.05)\u003c/p\u003e \u003cp\u003e*Differs by Dunnett's test when compared to cephalaxin (positive control) at 5%.\u003c/p\u003e \u003cp\u003e+Differs by Dunnett's test when compared to water (negative control) at 5%.\u003c/p\u003e \u003cp\u003eThe pure ZnO and ZnOCl nanoparticles, ZnO doped with Ca, Cu, Fe, K, Mg, Mn, Mo, and Ni; ZnOCl doped with Cu; FeO, MnO and NiO nanoparticles, as well the water (negative control) did not inhibit bacterial growth.\u003c/p\u003e \u003cp\u003eThe bacterium was detected in 100% of the untreated inoculated seeds (water \u0026ndash; positive control) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e), not differing significantly from the inoculated seeds treated with CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles, ranging from 88 to 98%. No bacteria were detected in uninoculated seeds.\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\u003eDetection of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e in inoculated lettuce seeds and treated with different nanoparticles.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDetection (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCuO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e88 a*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e98 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e95 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:5.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e96 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWater (inoculated, positive control)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWater (uninoculated, negative control)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.0 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eCV (%) 8.07\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\u003eMeans followed by different lowercase letters in the column differ significantly, according to the Scott-Knott test (P\u0026thinsp;=\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e*Differs by Dunnett's test when compared to water (uninoculated, negative control) at 5%.\u003c/p\u003e \u003cp\u003eThe germination and emergence percentage (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) of lettuce seeds inoculated and treated with CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles did not differ significantly of the control (water), range from 99 to 100%, and 66 to 81%, respectively. Only NiO (93%) nanoparticle reduced the seed germination and seedling emergence. For uninoculated seeds, ZnOCl:5Ag reduced the seed germination (88%), differing from the other treatments. The germination percentage of inoculated and uninoculated seeds did not differ statistically when treated with CuO and NiO. The emergence percentage of inoculated seeds increased when treated with CuO, ZnO:1.0Ag and ZnOCl:5.0Ag compared with uninoculated seed.\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\u003eGermination and emergence percentage of inoculated lettuce seeds, with \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e and treated with different nanoparticles.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eGermination (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003eEmergence (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eInoculated\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eUninoculated\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003eInoculated\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003eUninoculated\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCuO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100 aA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e96 aA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e70 aA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e50 bB\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e93 bA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95 aA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e44 bB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e64 aA\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100 aA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e95 aB\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e66 aA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e32 cB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:5.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e99 aA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e88 bB*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e81 aA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e28 cB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWater (control)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e100 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e100 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e58 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e48 a\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\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e3.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c6\" namest=\"c5\"\u003e \u003cp\u003e17.06\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\u003eMeans followed by different lowercase letters in the column and uppercase letters in the row differ significantly according to the Scott-Knott test (P\u0026thinsp;=\u0026thinsp;0.05)\u003c/p\u003e \u003cp\u003e*Differs by Dunnett's test when compared to water (negative control) at 5%.\u003c/p\u003e \u003cp\u003eThe area under the disease progress curve (AUDPC), for lettuce bacterial leaf spot, using different nanoparticles showed no significant difference between the preventive and curative applications (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). In the preventive application, CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles, and copper (30.6) significantly reduced the disease severity when compared to the water-untread control (252.9). In the preventive application, all treatments reduced the progress curve of lettuce bacterial leaf spot compared to the untreated control, reducing the disease severity. In the curative application, CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles, and copper significantly reduced the lettuce bacterial leaf spot severity.\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\u003eArea under the disease progress curve for lettuce bacterial leaf spot, using different nanoparticles in preventive and curative application.\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\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eApplication\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePreventive\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eCurative\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCuO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e54.6 aA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e68.4 aA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNiO\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e64.2 aA\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e205.2 bB\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnO:1.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e69.0 aA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e76.8 aA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eZnOCl:5.0Ag\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e34.8 aA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e71.4 aA*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCopper\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e30.6 aA*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e107.4 aB*\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eWater (control)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e252.9 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e249.9 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMedia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e84.4 A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e129.9 A\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003eCV (%) 44.61\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\u003eMeans followed by lowercase letters in the column and uppercase letters in the row are significantly different, by the Scott-Knott test (P\u0026thinsp;=\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e*Differs by Dunnett's test when compared to water (positive control) at 5%.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study showed the nanoparticles bactericidal potential of ZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO, to inhibit the bacterial growth of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e. Similar results were observed in the growth inhibition of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003egardneri\u003c/em\u003e (Fraga et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, Oliveira et al. \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), \u003cem\u003ePantoea ananatis\u003c/em\u003e, \u003cem\u003eDickeya zeae\u003c/em\u003e, and \u003cem\u003eXanthomonas vasicola\u003c/em\u003e pv. \u003cem\u003evasculorum\u003c/em\u003e (Mamede et al. \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Mamede et al. \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), using the same nanoparticles. Thus, the ZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO nanoparticles showed significant antibacterial property and can be used to bacterial control.\u003c/p\u003e \u003cp\u003eZnO:Ag, ZnO:Au, ZnOCl:Ag nanoparticles at 10 and 1 mg/mL concentrations, and CuO, and NiO nanoparticles at 10 mg/mL inhibited the growth of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians.\u003c/em\u003e Only the ZnO and ZnOCl nanoparticles doped with gold (Au) and silver (Ag) (ZnO:Ag, ZnO:Au, ZnOCl:Ag) inhibited the bacterial growth showing the antibacterial activity. The silver ions antibacterial mechanism is due the, DNA losses its replication ability (Feng et al \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e2000\u003c/span\u003e), resulting in the ribossomal inactivation and in ATP production (Yamanaka et al. \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e2005\u003c/span\u003e). FeO, MnO, ZnO, ZnO:Ca, ZnO:Cu, ZnO:Fe, ZnO:K, ZnO:Mg, ZnO:Mn, ZnO:Mo, ZnO:Ni, ZnOCl, and ZnOCl:Cu nanoparticles did not inhibit bacterial growth. This indicates that the isolate UFU E125 of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e is not sensitive to those nanoparticles.\u003c/p\u003e \u003cp\u003eIn this study the nanoparticles did not reduce the bacteria in inoculated lettuce seed, maybe due to the methodology used to inoculate the seeds, using glycerol and gelatin onto bacterial growth in Petri dishes. The seeds became completely involve with the bacteria and the nanoparticles were not enough to control them, other essays of lettuce seeds inoculation must be carried out to assess the inoculation efficacy for the control the bacteria. Pathogen-free seeds has become an important strategy for bacterial control, and nanoparticles have been shown promise in seed treatment for the control of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003egardneri\u003c/em\u003e in tomato seeds (Fraga et al., \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, Oliveira et al. \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2023\u003c/span\u003e) and \u003cem\u003eAlternaria alternata\u003c/em\u003e in wheat seeds (Duarte et al. \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e2022\u003c/span\u003e). In this study nanoparticles did not inhibit the seed germination and seedlings emergence of lettuce, as well as the seed of corn (Pokhrel and Dubey \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2013\u003c/span\u003e), wheat (Feizi et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2013\u003c/span\u003e), tomato (Siddiqui and Al-Whaibi \u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Fraga et al. \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, Oliveira et al. \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2023\u003c/span\u003e), corn (Segatto et al. \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), and cucumber (De La Rosa et al. \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e2013\u003c/span\u003e) treated with nanoparticles there was no reduction in the seed germination.\u003c/p\u003e \u003cp\u003eAlthough the AUDPC for lettuce bacterial leaf spot using different nanoparticles did not differ in preventive and curative application, the preventive application showed less disease severity, possibly due to the formation of a protective barrier created by the nanoparticles in the leaf tissue, before inoculation, making it difficult for the bacteria to penetrate. Preventive application of ZnO nanoparticles to control bacterial speck caused by \u003cem\u003ePseudomonas syringae\u003c/em\u003e pv. \u003cem\u003etomato\u003c/em\u003e induced the defense mechanism of tomato plants, showing higher self-defense enzyme activity (Elsharkawy et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). Also, the preventive application of nanoparticles of ZnO:0.5Mo, ZnO:1K, and ZnO:1Mg reduce the tomato bacterial spot (Fraga et al. 2020). In this study, CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles reduced disease severity and showed potential for use in the management of lettuce bacterial leaf spot, since there are no products registered to control the disease in Brazil.\u003c/p\u003e \u003cp\u003eBacterial diseases are difficult to control, especially when already established in the field, and preventive measures are considered the most important approaches to avoid initial infection, and the use of nanoparticles can reduce lettuce bacterial leaf spot severity. Nanoparticles have shown beneficial effects in plants, activating defense mechanisms and micronutrient uptake (Cartwright et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). ZnO nanoparticles can interact with the bacterial surface or core, exhibiting distinct bactericidal mechanisms: altering the viscosity and structure of the cell membrane, increasing its permeability (Hou et al. \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Siddiqi et al. \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e2018\u003c/span\u003e), damaging the cell wall and allowing toxic compounds to enter the cytoplasm (Czyżowska and Barbasz, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2020\u003c/span\u003e), and inducing resistance in plants, protecting against the pathogens (Elsharkawy et al. \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO nanoparticles inhibited the bacterial growth of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians in vitro\u003c/em\u003e. CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles did not reduce the bacterium in inoculated lettuce seeds, and did not reduce the seed germination and seedling emergence. The preventive and curative application of CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag reduced the bacterial leaf spot severity. The nanoparticles showed promising to manage bacterial leaf spot in lettuce.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eConflict of interest\u003c/h2\u003e \u003cp\u003eThe authors declare no conflicts of interest.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e \u003cp\u003eCAPES and CNPq\u003c/p\u003e\u003ch2\u003eAuthor contribution\u003c/h2\u003e \u003cp\u003eNMF performed material preparation, data collection, analysis, and manuscript writing. NDT contributed to the study\u0026rsquo;s conception and design, and to the manuscript\u0026rsquo;s writing and revision. ACAS synthesized the nanocrystals. All authors approved the final manuscript.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e \u003cp\u003eThe authors thank CAPES (Coordena\u0026ccedil;\u0026atilde;o de Aperfei\u0026ccedil;oamento de Pessoal de N\u0026iacute;vel Superior, Brazil), and CNPq (Conselho Nacional de Desenvolvimento Cient\u0026iacute;fico e Tecnol\u0026oacute;gico, Brazil) for providing a scholarship to NMF, and to NDT (Research Productivity, Grant 302875/2022-0), respectively, and are grateful to Lara Caroline Borges Moreira for her contribution to data collection.\u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e \u003cp\u003eThe authors declare that the data supporting the findings of this study are available upon request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAllaker RP (2010) The use of nanoparticles to control oral biofilm formation. J Dent Res 89:1175\u0026ndash;1186\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCarisse O, Ouimet A, Toussaint V, Philion V (2000) Evaluation of the effect of seed treatments, bactericides, and cultivars on bacterial leaf spot of lettuce caused by \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e. Plant Disease 84:295\u0026ndash;299\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCartwright A, Jackson K, Morgan C, Anderson A, Britt DW (2020) A review of metal and metal-oxide nanoparticle coating technologies to inhibit agglomeration and increase bioactivity for agricultural applications. Agronomy 10:1018\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCzyżowska A, Barbasz A (2020) A review: zinc oxide nanoparticles friends or enemies? Int J Environ Health Res 32:885\u0026ndash;901\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDe La Rosa G, L\u0026oacute;pez-Moreno ML, Haro D, Botez CE, Peralta-Videa JR, Gardea-Torresdey JL (2013) Effects of ZnO nanoparticles in alfalfa, tomato, and cucumber at the germination stage: Root development and X-ray absorption spectroscopy studies. Pure Appl Chem 85:2161\u0026ndash;2174\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDuarte LC, Cat\u0026atilde;o HCRM, Tebaldi ND (2022) Nanoparticles and photodynamic therapy in the treatment and control of \u003cem\u003eAlternaria alternata\u003c/em\u003e in wheat seeds. Ci\u0026ecirc;ncia e Agrotecologia 46:e005222\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eElsharkawy M, Derbalah A, Hamza A, El-Shaer A (2020) Zinc oxide nanostructures as a control strategy of bacterial speck of tomato caused by \u003cem\u003ePseudomonas syringae\u003c/em\u003e in Egypt. Environ Sci Pollut Res 27:19049\u0026ndash;19057\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFayette J, Jones JB, Pernezny K, Roberts PD, Raid R (2018) Survival of \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e on lettuce in crop debris, irrigation water, and weeds in south Florida. Eur J Plant Pathol 151:341\u0026ndash;353\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFeizi H, Moghaddam PR, Shahtahmassebi N, Fotovat A (2013) Assessment of concentrations of nano and bulk iron oxide particles on early growth of wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L). Annual Rev Res Biology 3:752\u0026ndash;761\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFeng QL, Wu J, Chen GQ, Cui FZ, Kim TN, Kim JO (2000) A mechanistic study of the antibacterial effect of silver ions on \u003cem\u003eEscherichia coli\u003c/em\u003e and \u003cem\u003eStaphylococcus aureus\u003c/em\u003e. J Biomed Mater Res 52:662\u0026ndash;668\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFraga FS, Silva ACA, Dantas NO, Tebaldi ND, Luz JMQ (2021) Doped zinc-oxide nanocrystals for the control of tomato bacterial spot and \u003cem\u003eXanthomonas gardneri\u003c/em\u003e in seeds. Trop Plant Pathol 46:406\u0026ndash;413\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eHou J, Wu Y, Li X, Wei B, Li S, Wang X (2018) Toxic effects of different types of zinc oxide nanoparticles on algae, plants, invertebrates, vertebrates and microorganisms. Chemosphere 193:852\u0026ndash;860\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKado CI, Heskett MG (1970) Selective media for isolation of Agrobacterium, \u003cem\u003eCorynebacterium\u003c/em\u003e, \u003cem\u003eErwinia\u003c/em\u003e, \u003cem\u003ePseudomonas\u003c/em\u003e, and \u003cem\u003eXanthomonas\u003c/em\u003e. Phytopathology 60:969\u0026thinsp;\u0026ndash;\u0026thinsp;76\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKoide ST, Gilbertson RL (2017) Detection of \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e in lettuce seeds. In: Fatmi MB, Walcott RR, Schaad NW (eds) Detection of plant-pathogenic bacteria in seed and other planting material. APS, St. Paul., pp 173\u0026ndash;178\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMalavolta J\u0026uacute;nior VA, Beriam LOS, Almeida IMG, Rodrigues Neto J, Robbs CF (2008) Bact\u0026eacute;rias fitopatog\u0026ecirc;nicas assinaladas no Brasil: Uma atualiza\u0026ccedil;\u0026atilde;o. Summa Phytopathologica 34S:9\u0026ndash;87\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMamede MC, Mota RP, Silva ACA, Tebaldi ND (2022) Nanoparticles in inhibiting \u003cem\u003ePantoea ananatis\u003c/em\u003e and control maize white spot. Ci\u0026ecirc;ncia Rural 52:e20210481\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMamede MC, Silva ACA, Tebaldi ND (2024) \u003cem\u003eDickeya zeae, Pantoea ananatis\u003c/em\u003e, and \u003cem\u003eXanthomonas vasicola\u003c/em\u003e pv. \u003cem\u003evasculorum\u003c/em\u003e: control with the use of nanoparticles. Ci\u0026ecirc;ncia e Agrotecnologia 48:e018423\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eMorini\u0026egrave;re L, Burlet A, Rosenthal ER, Nesme X, Portier P, Bull CT, Lavire C, Fischer-Le Saux M, Bertolla F (2020) Clarifying the taxonomy of the causal agent of bacterial leaf spot of lettuce through a polyphasic approach reveals that \u003cem\u003eXanthomonas cynarae\u003c/em\u003e Tr\u0026eacute;baol 2000 emend. Timilsina 2019 is a later heterotypic synonym of \u003cem\u003eXanthomonas hortorum\u003c/em\u003e Vauterin 1995. Systematic and Applied Microbiology 43:126087\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eOliveira NS, Silva ACA, Tebaldi ND (2023) Simonkolleite nanoparticles for seed treatment and control of tomato bacterial spot caused by \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003egardneri\u003c/em\u003e. Ci\u0026ecirc;ncia e Agrotecnologia 47:e000623\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003ePokhrel LR, Dubey B (2013) Evaluation of developmental responses of two crop plants exposed to silver and zinc oxide nanoparticles. Sci Total Environ 452\u0026ndash;453:321\u0026ndash;332\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eR Core Team (2023) R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRobinson PE, Jones JB, Pernezny K (2006) Bacterial leaf spot of lettuce: Relationship of temperature to infection and potential host range of \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e. Plant Disease 90:465\u0026ndash;470\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSahin F, Miller SA (1997) Identification of the bacterial leaf spot pathogen of lettuce, \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e, in Ohio, and assessment of cultivar resistance and seed treatment. Plant Disease 81:1443\u0026ndash;1446\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSantos LCM, Silva ACA, Tebaldi ND (2024) Nanocrystals spraying interval for the control of tomato bacterial spot caused by \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003egardneri\u003c/em\u003e. Revista Ceres 71:e71018\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSegatto C, Ternus R, Junges M, Mello JMM, Luz GL, Riella HG, Silva LL, Laj\u0026uacute;s CR, Fiori MA (2018) Adsorption and incorporation of the zinc oxide nanoparticles in seeds of corn: germination performance and antimicrobial protection. Int J Adv Eng Res Sci 5:2456\u0026ndash;6495\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eShaner G, Finney RE (1977) The effect of nitrogen fertilization on the expression of slow-mildewing resistance in Knox wheat. Phytopathology 66:1051\u0026ndash;1056\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSiddiqi KS, Husen A, Rao RAK (2018) A review on biosynthesis of silver nanoparticles and their biocidal properties. J Nanobiotechnol 16:14\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSiddiqui MH, Al-Whaibi H (2014) Role of nano-SiO\u003csub\u003e2\u003c/sub\u003e in germination of tomato (\u003cem\u003eLycopersicum esculentum\u003c/em\u003e seeds Mill). Saudi J Bioligical Sci 21:13\u0026ndash;17\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSilva ACA, Z\u0026oacute;ia MAP, Correia LIV, Azevedo FVPV, Paula AT, Maia LP, Carvalho LS, Carvalho LN, Costa MPC, Giaretta LC, Rodrigues RS, \u0026Aacute;vila VM, Goulart LR, Dantas NO (2018) In: Celik TA (ed) Biocompatibility of doped semiconductors nanocrystals and nanocomposites. Cytotoxicity, InTech, pp 149\u0026ndash;161\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTebaldi ND, Martins OM, Mota LCBM (2015) Ocorr\u0026ecirc;ncia de \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e em alface, em Minas Gerais. Summa Phytopathologica 41:321\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eToussaint V, Benoit DL, Carisse O (2012) Potential of weed species to serve as a reservoir for \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e, the causal agent of bacterial leaf spot of lettuce. Crop Prot 41:64\u0026ndash;70\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eUmesh KC, Koike ST, Gilbertson RL (1996) Association of \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e with lettuce seed. Phytopathology 86:S3\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWellman-Desbians E (1999) Dissemination of \u003cem\u003eXanthomonas campestris\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e during lettuce transplant production. Phytopathology 89:S84\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYamanaka M, Hara K, Kudo J (2005) Bactericidal actions of a silver ion solution on \u003cem\u003eEscherichia coli\u003c/em\u003e, studied by energy-filtering transmission electron microscopy and proteomic analysis. Appl Environ Microbiol 71:7589\u0026ndash;7593\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"tropical-plant-pathology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tppa","sideBox":"Learn more about [Tropical Plant Pathology](https://www.springer.com/journal/40858)","snPcode":"40858","submissionUrl":"https://www.editorialmanager.com/tppa","title":"Tropical Plant Pathology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Detection, Germination, Lactuca sativa, Seeds, Severity","lastPublishedDoi":"10.21203/rs.3.rs-6066801/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6066801/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eLettuce bacterial leaf spot, caused by \u003cem\u003eXanthomonas hortorum\u003c/em\u003e pv. \u003cem\u003evitians\u003c/em\u003e is one important pathogen of lettuce. The use of nanoparticles offers a new approach to controlling the disease. The objective of this work was to investigate the use of nanoparticles in the control of lettuce bacterial leaf spot and in seed treatment. Nanoparticles toxicity was evaluated by determining the \u003cem\u003ein vitro\u003c/em\u003e bacterial growth inhibition zone. Lettuce seeds were inoculated with the bacteria and treated with CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles, the percentages of bacteria detected in the seeds, seed germination and seedlings emergence were determined. For the control of bacterial leaf spot, CuO, NiO, ZnO:1.0Ag and ZnOCl:5.0Ag nanoparticles were sprayed on lettuce plants in the preventive and curative application. In the preventive application, CuO, NiO, ZnO:1Ag, ZnOCl:5Ag, water and copper were sprayed, after three days, the plants were inoculated with a bacterial suspension (10\u003csup\u003e8\u003c/sup\u003e CFU/mL). In the curative application, the plants were inoculated with the bacteria, and three days later sprayed with the nanoparticles. Disease severity was assessed and the area under the disease progress curve was calculated. ZnO:Ag, ZnO:Au, ZnOCl:Ag, CuO, and NiO nanoparticles inhibited bacterial growth \u003cem\u003ein vitro\u003c/em\u003e. CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles did not reduce the bacterium in inoculated lettuce seeds and did not reduce the seed germination and seedling emergence. The preventive and curative application of CuO, ZnO:1.0Ag, and ZnOCl:5.0Ag nanoparticles reduced the lettuce bacterial leaf spot severity. The nanoparticles are alternative to manage lettuce bacterial leaf spot.\u003c/p\u003e","manuscriptTitle":"Nanoparticles for the control of lettuce bacterial leaf spot (Xanthomonas hortorum pv. vitians)","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-11 10:51:28","doi":"10.21203/rs.3.rs-6066801/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2025-03-10T14:16:15+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-03-07T10:38:19+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Tropical Plant Pathology","date":"2025-03-05T11:27:45+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-03-04T17:55:01+00:00","index":"","fulltext":""},{"type":"submitted","content":"Tropical Plant Pathology","date":"2025-02-28T16:12:53+00:00","index":"","fulltext":""},{"type":"decision","content":"Major revisions","date":"2025-02-28T12:32:38+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"tropical-plant-pathology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"tppa","sideBox":"Learn more about [Tropical Plant Pathology](https://www.springer.com/journal/40858)","snPcode":"40858","submissionUrl":"https://www.editorialmanager.com/tppa","title":"Tropical Plant Pathology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"90a38379-6257-4052-8d24-5b9bacbed7e7","owner":[],"postedDate":"March 11th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-11-12T11:45:55+00:00","versionOfRecord":[],"versionCreatedAt":"2025-03-11 10:51:28","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6066801","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6066801","identity":"rs-6066801","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}