山东临沭花生焦斑菌株多菌灵抗药性的研究

Resistance of peanut scorch spot pathogen Leptosphaerulina arachidicola to carbendazim in Linshu Shandong

从山东临沭花生田表现焦斑病症状的花生叶片上分离病原菌,对该地及其他地方采集的焦斑病病原菌进行r DNA-ITS区的核苷酸序列分析,测定多菌灵和其他杀菌剂对焦斑病菌的抑制能力,比较了不同焦斑病菌分离物在PSA培养基上的生长速率。结果表明,焦斑症状的病原菌为落花生小光壳菌（Leptosphaerulina arachidicola）。12株临沭分离物中3株对多菌灵具有抗药性,抗药性比例达25%。在PSA平板上,33.33～1 666.7mg/L的多菌灵对临沭多菌灵抗性分离物的抑菌率为9.4%～14.2%,3 333.3mg/L的多菌灵对抗性菌的抑菌率为45.2%。多菌灵抗性菌对20%戊唑醇＋烯肟菌胺悬浮剂,30%醚菌酯和70%代森联同样具有抗药性,但是对70%丙森锌可湿性粉剂、30%戊唑醇悬浮剂、25%代森锰锌＋8%三唑酮可湿性粉剂、丙环唑乳油等敏感。在PSA培养基上培养12d,临沭多菌灵抗性菌的生长速率曲线呈直线,与其他多菌灵敏感菌的生长速率无显著差异。

The pathogens of scorch spot disease were isolated from peanut leaves collected in Linshu,Shandong Province and other places. They were identified as Leptosphaerulina arachidicola by sequence analysis of genomic ITS region. 3 of 12 Linshu isolates were resistant to carbendazim on PSA medium containing 33. 3mg / L carbendazim,while other isolates were susceptible. Carbendazim resistant isolates could grow on PSA medium containing 3 333. 3mg / L carbendazim and were also resistant to 30% azoxystobin,20% tebuconazole ＋ hey oxime amine,and 70% polyram,but susceptible to 30% tebuconazole,10% difenoconazole,propiconazole,25% mancozeb ＋ 8% triazolene and 70% propineb. There was no significant difference in colony diameters between carbendazim resistant and susceptible isolates on PSA medium after 12 days.