STUDY ON A FOLIAR APPLICATION OF ACIBENZOLAR-S-METHYL TO INDUCE RESISTANCE TO ASIAN RUST IN SOYBEANS AND GRAY LEAF SPOT OF MAIZE

ABSTRACT Induced systemic resistance may present promising benefits for the management of various diseases of plants. In soybeans and corn this tactic could bring benefits such as reduction of damage and lower production costs. In order to evaluate the effects of the application of acibenzolar-S-methyl (ASM) on soybeans and corn for the control of Phakopsora pachyrhizi H. Sydow & P. Sydow and Cercospora spp. (C. zeae-maydis Tehon & Daniels, Zeina C. Crous & U. Braun and C. sorghi var. Maydis Everh & Ellis), four field experiments were conducted with these crops. In soybeans, the experiment was conducted in Maracaju/MS, Brazil, on the variety CD 219 RR with the application of 5 different treatments consisting of the spraying of herbicide, insecticides and fungicides with and without the association of ASM at different stages of the crop. In corn, 2 experiments were conducted in the 2008 off-season in Aral Moreira-MS (hybrid Somma) and Maracaju/MS (hybrid 2B710) with the application of ASM alone and in combination with azoxystrobin + cyproconazole at 2 different stages of plant development. Another test was conducted with corn in the summer of 2008/2009 with the hybrid AG 9040 in Maracaju/MS, also with the application of ASM alone and in combination with azoxystrobin + cyproconazole sprayed on up to 3 different stages of the corn plants. None of the experiments conducted showed benefits of using ASM either alone or in mixture with fungicides for the control of soybean rust and gray leaf spot in maize; only the use of chemical fungicides controlled the fungus, regardless of the addition of ASM.

摘要：诱导系统抗性在多种植物病害防控中具备良好应用前景。针对大豆与玉米，该策略可实现病害危害减轻与生产成本降低的效益。为评估活化酯（acibenzolar-S-methyl，ASM）喷施于大豆、玉米以防控亚洲大豆锈菌（Phakopsora pachyrhizi H. Sydow & P. Sydow）及尾孢菌属（Cercospora spp.，包含玉米灰斑病菌C. zeae-maydis Tehon & Daniels、玉米尾孢菌Zeina C. Crous & U. Braun及高粱尾孢玉米变种C. sorghi var. Maydis Everh & Ellis）的防控效果，研究针对两种作物共开展4项田间试验。大豆试验于巴西南马托格罗索州马卡尤（Maracaju/MS）开展，供试品种为CD 219 RR，设置5种处理方案，涵盖除草剂、杀虫剂、杀菌剂单施，以及分别在作物不同生育阶段与活化酯复配的喷施处理。玉米试验共3项：2008年季闲期，分别在南马托格罗索州阿拉尔莫雷拉（Aral Moreira-MS，供试杂交种为Somma）与马卡尤（Maracaju/MS，供试杂交种为2B710）各开展1项试验，处理设置为活化酯单施及与嘧菌酯+环丙唑醇复配，施药时期设为2个植株发育阶段；2008/2009年夏季，于马卡尤（Maracaju/MS）开展另一项玉米试验，供试杂交种为AG 9040，同样设置活化酯单施及与嘧菌酯+环丙唑醇复配的处理，施药最多覆盖3个玉米植株发育阶段。所有试验均未显示活化酯单施或与杀菌剂复配可有效防控大豆锈病及玉米灰斑病；仅单用化学杀菌剂可实现病原菌防控，添加活化酯无额外增效效果。