Culbreath A K, Stevenson K L, Brenneman T B
Professor, Department of Plant Pathology, The University of Georgia Coastal Plain Experiment Station, Tifton 31793-0748.
Associate Professor, Department of Plant Pathology, The University of Georgia, Athens 30602-7274.
Plant Dis. 2002 Apr;86(4):349-355. doi: 10.1094/PDIS.2002.86.4.349.
Recent registration of sterol biosynthesis inhibitor and strobilurin fungicides for control of early (Cercospora arachidicola) and late (Cercosporidium personatum) leaf spot diseases of peanut (Arachis hypogaea) has renewed interest in the potential for loss of disease control due to fungicide resistance. The objectives of this study were to use the systemic fungicide benomyl, the protectant fungicide chlorothalonil, and late leaf spot of peanut as a model system to compare fungicide application strategies for fungicide resistance management. Field experiments were conducted at Tifton and Plains, GA, in 1995 and 1996 to determine the effects of alternate applications, mixtures, and alternating block applications of chlorothalonil and benomyl compared with full-season applications of two rates of chlorothalonil and two rates of benomyl alone on late leaf spot of peanut and on the proportion of the pathogen population resistant to benomyl following the various regimes. Tank mix combinations of half rates of the two fungicides and alternations of the full rates of the two fungicides provided better (P ≤ 0.05) control of late leaf spot than full-season applications of either rate of benomyl alone, and were comparable to full rates of chlorothalonil alone. Neither tank mixes nor alternating sprays prevented an increase in the relative frequency of benomyl-resistant isolates compared with other treatments in which benomyl was used. Both mixtures and alternate applications of chlorothalonil and benomyl were effective for management of leaf spot in fields where benomyl alone did not provide season-long leaf spot control.
最近，用于防治花生早叶斑病（花生尾孢菌）和晚叶斑病（花生小球腔菌）的甾醇生物合成抑制剂和甲氧基丙烯酸酯类杀菌剂的登记，重新引发了人们对因抗药性导致病害防治失败可能性的关注。本研究的目的是以系统性杀菌剂苯菌灵、保护性杀菌剂百菌清以及花生晚叶斑病为模型系统，比较不同的杀菌剂施用策略对杀菌剂抗性管理的效果。1995年和1996年在佐治亚州的蒂夫顿和平原进行了田间试验，以确定百菌清和苯菌灵交替施用、混合施用以及交替分区施用，与单独以两种剂量全季施用百菌清和两种剂量全季施用苯菌灵相比，对花生晚叶斑病的影响，以及在不同处理方式后病原菌群体中对苯菌灵产生抗性的比例。两种杀菌剂半量的桶混组合以及两种杀菌剂全量的交替施用，对花生晚叶斑病的防治效果优于单独全季施用任一剂量的苯菌灵（P≤0.05），且与单独全量施用百菌清的效果相当。与使用苯菌灵的其他处理方式相比，无论是桶混组合还是交替喷雾处理，均未能阻止对苯菌灵产生抗性的分离株相对频率的增加。在单独使用苯菌灵无法实现全季叶斑病防治的田间，百菌清和苯菌灵的混合施用及交替施用对叶斑病的管理均有效。
