葡萄炭疽病菌对甲基硫菌灵、戊唑醇和醚菌酯的敏感性检测

采用菌丝生长法检测了78株采自浙江省杭州、嵊州和嘉兴 3地的葡萄炭疽病菌 Colletotrichum gloeosporioides 对甲基硫菌灵、戊唑醇和醚菌酯的敏感性。结果表明:供试病菌已对甲基硫菌灵产生了严重的抗药性,抗性频率为51.3%,且均为高水平抗药性菌株;78个供试菌株对戊唑醇的EC50值在0.04～21.56 μg/mL之间,平均为1.63 μg/mL,其中L-58菌株的敏感性最低,EC50值为21.6 μg/mL。旁路氧化酶抑制剂水杨肟酸(SHAM)处理对醚菌酯抑制葡萄炭疽病菌菌丝生长的活性表现出明显的增效作用:无SHAM存在时,醚菌酯抑制菌丝生长的EC50(EC50Q)值在0.03～436.55 μg/mL之间,平均为27.77 μg/mL;当SHAM的处理质量浓度为50 μg/mL时,EC50(EC50Q+S)值在0.01～15.20 μg/mL 之间,平均为4.40 μg/mL。旁路氧化的相对贡献值 F 最低为0,最高为155.47,平均为20.09。

Detection of sensitivity of grape anthracnose to thiophanate methyl, tebuconazole and kresoxim-methyl

Seventy eight isolates of Colletotrichum gloeosporioides collected from grapes in Hangzhou,Shengzhou and Jiaxing of Zhejiang Province were characterized for sensitivity to thiophanate methyl,tebuconazole and kresoxim-methyl by mycelial growth method.The results showed that the isolates had developed serious resistance to benzimidazole fungicides with resistance frequency of 51.3%,which belong to high level resistance.The EC50 values of tebuconazole,a demethylation inhibitor to the isolates ranged from 0.04 to 21.56 μg/mL with a mean value of 1.63 μg/mL.Among them,the isolate of L-58 showed the least sensitivity with EC50 value of 21.6 μg/mL.SHAM,a specific inhibitor of alternative oxidase,showed notable synergistic interaction with kresoxim-methyl against mycelial growth of C.gloeosporioides.In the absence of SHAM,the medium effective concentrations(EC50Q) inhibiting growth rate of the tested population by kresoxim-methyl ranged from 0.03 to 436.55 μg/mL,with an average value of 27.77 μg/mL.In the presence of 50 μg/mL SHAM,the EC50(EC50Q+S) ranged from 0.01 to15.20 μg/mL,with an average value of 4.40 μg/mL.The factor value(F=EC50Q/EC50Q+S) for the impact of alternative respiration on sensitivity to kresoxim-methyl ranged from 0 to 155.47,with an average of 20.09.