Chitrampalam P, Figuli P J, Matheron M E, Subbarao K V, Pryor B M
Division of Plant Pathology and Microbiology, Department of Plant Sciences, University of Arizona, Tucson 85721.
Department of Plant Pathology, University of California, Davis 95616.
Plant Dis. 2008 Dec;92(12):1625-1634. doi: 10.1094/PDIS-92-12-1625.
Field experiments were conducted over 2 years in Yuma County, AZ, and Imperial County, CA, to determine the efficacy of several biocontrol agents for the management of lettuce drop caused by Sclerotinia spp. Commercial formulations of Trichoderma harzianum (Plantshield, Supersivit), Gliocladium virens (Soilgard), Coniothyrium minitans (Contans), and Bacillus subtilis (Companion) were evaluated and compared with the chemical fungicide iprodione (Rovral) against Sclerotinia sclerotiorum and S. minor. A single application of biocontrol products or of Rovral did not reduce lettuce drop caused by either Sclerotinia species. However, two applications of Contans, one at planting and one at post-thinning, significantly reduced the incidence of lettuce drop caused by S. sclerotiorum and increased yield but had no effect on S. minor at both locations in both years. Two applications of other biocontrol products did not significantly reduce disease incidence despite medium to high recovery following application. In contrast, Contans was only sporadically recovered following application. In vitro fungicide sensitivity evaluation revealed that both Trichoderma and Gliocladium species were tolerant to iprodione, dicloran (Botran), and vinclozolin (Ronilan) up to 1,000 ppm a.i., whereas both Sclerotinia spp. and C. minitans were sensitive to all three fungicides above 1 ppm. In summary, Contans was the most effective treatment for the control of lettuce drop caused by S. sclerotiorum, but no treatment was effective against S. minor in the desert lettuce production systems.
在亚利桑那州尤马县和加利福尼亚州帝国县进行了为期两年的田间试验，以确定几种生物防治剂对防治由核盘菌属引起的生菜菌核病的效果。对哈茨木霉（Plantshield、Supersivit）、绿粘帚霉（Soilgard）、盾壳霉（Contans）和枯草芽孢杆菌（Companion）的商业制剂进行了评估，并与化学杀菌剂异菌脲（Rovral）针对核盘菌和小核盘菌进行了比较。单次施用生物防治产品或Rovral均未降低由任何一种核盘菌引起的生菜菌核病。然而，两次施用Contans，一次在种植时，一次在间苗后，显著降低了由核盘菌引起的生菜菌核病发病率并提高了产量，但在两年中两个地点对小核盘菌均无效果。其他生物防治产品两次施用后尽管施用后回收率中等至较高，但并未显著降低病害发病率。相比之下，Contans施用后仅偶尔能回收。体外杀菌剂敏感性评估显示，木霉属和粘帚霉属对高达1000 ppm a.i.的异菌脲、氯硝胺（Botran）和乙烯菌核利（Ronilan）均具有耐受性，而两种核盘菌属和盾壳霉对高于1 ppm的这三种杀菌剂均敏感。总之，Contans是防治由核盘菌引起的生菜菌核病最有效的处理方法，但在沙漠生菜生产系统中没有处理方法对小核盘菌有效。
