江苏垦区小麦赤霉病菌对多菌灵的抗性监测及其替代杀菌剂的防病效果

近年来的调查结果表明,江苏垦区小麦赤霉病菌群体中抗多菌灵菌株的频率逐年上升,多菌灵防效逐年下降,部分农场采用多菌灵防治几乎失效。为了筛选替代多菌灵的药剂,我们在白马湖等6个农场对几种新杀菌剂进行了田间药效试验。结果表明,25%氰烯菌酯SC、40%叶菌唑SC和25%丙硫菌唑WP在所有农场都有较好的防治效果,其中25%丙硫菌唑WP对小麦赤霉病的防治效果最好,在所有农场其防效都超过80%,防治后乳熟期和成熟期病穗率变化不大。40%叶菌唑SC、25%丙硫菌唑WP以及25%氰烯菌酯SC和43%戊唑醇SC混用有显著增产作用,并能大幅度降低籽粒中DON含量。作者认为赤霉病的防治应立足种植抗(耐)病品种,扬花期选用有效杀菌剂适期进行防治。氰烯菌酯、叶菌唑和丙硫菌唑可作为多菌灵的替代药剂。

Resistance monitoring of Fusarium asiaticum to carbendazim in Jiangsu state farms and the efficacy of alternative fungicides to wheat scab

Previous studies showed that the resistance frequency of Fusarium asiaticum isolates to carbendazim in Jiangsu state farms had increased in the field since 2012. The efficacy of carbendazim for controlling wheat scab had declined severely and even no control efficacy in some areas. In order to screen fungicides alternative to carbendazim, field trials were conducted in Baimahu farm and other five farms with several new fungicides. The results showed that phenamacril 25% SC, metconazole 40% SC andprothioconazole 25% WP had a higher efficacy, prothioconazole 25% WP had the best and most stable effect on wheat scab with the efficacy of above 80% in all farms, and there was no significant difference in disease incidence between milk and mature stage of wheat. Metconazole 40% SC, prothioconazole 25% WP and mixture of phenamacril 25% SC and tebuconazole 43% SC sprayed at anthesis stage reduced DON content and increased wheat yield significantly. The authors suggested that the strategy for wheat scab control should depend on culturing resistant or tolerant wheat varieties and spraying effective fungicides alternately at anthesis stage of wheat. Metconazole, prothioconazole and phenamacril can be used as alternatives to carbendazim.