番茄叶霉病菌对氟唑菌酰羟胺敏感基线的建立及氟唑菌酰羟胺田间防病效果评价

氟唑菌酰羟胺(pydiflumetofen)是一种新型SDHI类杀菌剂,目前在中国仅登记用于防治小麦赤霉病和油菜菌核病,为明确其对番茄叶霉病的防治潜力,测定了番茄叶霉病菌Passalora fulva不同发育阶段以及山东省不同地区采集的菌株对氟唑菌酰羟胺的敏感性,并验证了其田间防治效果.结果表明:氟唑菌酰羟胺对番茄叶霉...

Sensitivity baseline to pydiflumetofen in Passalorafulvaand control efficacy of pydiflumetofen against tomato leaf mold

Pydiflumetofen is a novel succinate dehydrogenase inhibitor (SDHI), which shows excellent inhibitory activity to many plant pathogens, such as Fusarium graminearum and Sclerotinia sclerotiorum. In this study, the sensitivity to pydiflumetofen of Passalora fulva strains collected from 8 cities in Shandong Province were tested by using mycelial growth rate method. In addition, the control efficacy of pydiflumetofen to tomato leaf mold were also investigated in field. The results showed that pydiflumetofen had strong inhibitory activity on three developmental stages of P. fulva, and the inhibitory activities on spore gemination and germ tube elongation were higher than that on mycelial growth. Inhibition rate of pydiflumetofen to spore gemination and germ tube elongation of P. fulva was over 50% at 0.10 μg/mL. The EC₅₀ values frequency distribution of 103 P. fulva isolates to pydiflumetofen on mycelial growth was a unimodal curve and could be regarded as the baseline sensitivity. The EC₅₀ values ranged from 0.04 to 1.74 μg/mL, with a mean of (0.67 ± 0.41) μg/mL. In field trials of two years, after the last application at the dose of 200 g a.i./hm2, the control efficacy of pydiflumetofen was above 80%, which was significantly higher than that of thiophanate-methyl (540 g a.i./hm2) and fluopyram (150 g a.i./hm2). This study provides data support for monitoring the resistance of tomato leaf mold to pydiflumetofen and for efficient controlling tomato leaf mold.