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期 刊 ：植物保护学报 2011年

关键词：辣椒疫霉菌；双炔酰菌胺；敏感性；交互抗性；遗传稳定性；

Keywords:Phytophthora capsici, mandipropamid, sensitivity, cross resistance, stability of heredity,

摘 要 ：采用菌丝生长速率法测定了不同地区115个辣椒疫霉菌株对双炔酰菌胺的敏感性,同时测定了紫外诱导和药剂驯化的10个抗性突变体及其4个亲本菌株对双炔酰菌胺、烯酰吗啉、甲霜灵、嘧菌酯和霜脲氰的敏感性。山东青州、寿光和河北定兴、藁城4地辣椒疫霉菌株均对双炔酰菌胺较敏感,且敏感性差异不显著。不同抗性水平菌株对5种药剂的敏感性测定和相关性分析结果显示,双炔酰菌胺与其它几类药剂之间均不存在交互抗性。10个抗性突变体继代培养11代后,8个抗性突变体抗药性不能稳定遗传;2个抗性突变体抗药性不仅能够稳定遗传,且EC₅₀值维持在很高水平,分别为1 429.524 μg/mL和6 872.476 μg/mL,因此,双炔酰菌胺的连续使用有利于抗药群体的发展。

Abstract:The sensitivities of 115 isolates of Phytophthora capsici collected from different regions to mandipropamid were tested by measuring mycelial growth rate. Ten resistant-mutants and 4 sensitive isolates to mandipropamid were used to study its cross resistance with dimethomorph, metalaxyl, azoxystrobin and cymoxanil by comparing their sensitivity to diverse active mechanism fungicides. The results showed that there were no significant differences among the EC₅₀ of mandipropamid to isolates from Qingzhou, Shouguang, Dinxing and Gaocheng regions, and all those isolates were more sensitive to mandipropamid. The linear regression showed that there were no cross resistances between mandipropamid and other diverse active mechanism fungicides. After 11 successive incubation, the sensitivities of 2 of 10 resistant-mutants to mandipropamid could maintain their resistance inheritable stability with the EC₅₀ of 1429.524μg/mL and 6872.476μg/mL respectively, but the other 8 could not maintain it. Our results indicated that the continuous use of mandipropamid was beneficial to development of resistance populations.

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