文献类型： 外文期刊

作者： Liang, Hongjie ¹ ; Li, Jinli ¹ ; Luo, Chaoxi ¹ ; Li, Jianhong ¹ ; Zhu, Fu-Xing ¹ ;

作者机构： 1.Huazhong Agr Univ, Coll Plant Sci & Technol, Wuhan 430070, Hubei, Peoples R China

2.Gansu Acad Agr Sci, Potato Res Inst, Lanzhou 730070, Gansu, Peoples R China

关键词： chemical; disease management; fruit; fungi; small fruits

期刊名称：PLANT DISEASE （ 影响因子：4.438； 五年影响因子：4.7 ）

ISSN： 0191-2917

年卷期： 2019 年 103 卷 8 期

页码：

收录情况： SCI

摘要： It is a common practice to add salicylhydroxamic acid (SHAM) into artificial medium in the in vitro sensitivity assay of fungal phytopathogens to the quinone outside inhibitor (QoI) fungicides. The rationale for adding SHAM is to inhibit fungal alternative oxidase, which is presumed to be inhibited by secondary metabolites of plants. Therefore, the ideal characteristics of SHAM should be almost nontoxic to phytopathogens and have no significant effect on control efficacy of fungicides. However, this study showed that the average effective concentration for 50% inhibition (EC50) of mycelial growth values of SHAM were 97.5 and 401.4 mu g/ml for Sclerotinia sclerotiorum and Botrytis cinerea, respectively. EC50 values of the three QoI fungicides azoxystrobin, kresoxim-methyl, and trifloxystrobin in the presence of SHAM at 20 and 80 mu g/ml for S. sclerotiorum and B. cinerea, respectively, declined by 52.7 to 78.1% compared with those without SHAM. For the dicarboximide fungicide dimethachlone, the average EC50 values in the presence of SHAM declined by 18.2% (P = 0.008) for S. sclerotiorum and 35.9% (P = 0.012) for B. cinerea. Pot experiments showed that SHAM increased control efficacy of the three QoI fungicides against the two pathogens by 43 to 83%. For dimethachlone, SHAM increased control efficacy by 134% for S. sclerotiorum and 86% for B. cinerea. Biochemical studies showed that SHAM significantly inhibited peroxidase activity (P = 0.024) of B. cinerea and esterase activity (P = 0.015) of S. sclerotiorum. The strong inhibitions of SHAM per se on mycelial growth of B. cinerea and S. sclerotiorum and significant influences on the sensitivity of the two pathogens to both the QoI fungicides and dimethachlone as well as inhibitions on peroxidase and esterase indicate that SHAM should not be added in the in vitro assay of sensitivity to the QoI fungicides.