山药炭疽病病原菌的分离鉴定及其室内毒力测定

Isolation and identification of pathogen of yam anthracnose and laboratory test of virulence

为了明确湖南双峰青树坪山药炭疽病的病原菌种类及筛选适合的化学药剂,将采集的山药炭疽病病样通过组织分离法结合形态学和分子生物学分析对分离菌株进行分离鉴定,采用喷雾接种法测定致病性,采用菌丝生长速率法测定4种化学药剂对山药炭疽病的毒力。结果表明,引起该地区的山药炭疽病病原菌是胶孢炭疽菌(Colletotrichum gloeosporioides);5%己唑醇悬浮剂、10%苯醚甲环唑水分散粒剂、32.5%苯甲嘧菌酯悬浮剂3种化学药剂对山药炭疽病病原菌均具有较好的抑菌效果;山药炭疽病菌对药剂32.5%苯甲嘧菌酯悬浮剂最为敏感,其EC_(50)为0.0204 mg·L^(-1)。试验结果可为山药炭疽病害的防治提供参考。

In order to identify of pathogenic species and screen suitable chemical agents for the anthracnose disease of Hunan Shuangfeng Qingshuping Yam.The collected samples of Yam anthracnose were separated and identified by tissue separation method combined with morphology and molecular biology.The pathogenicity was determined by spray inoculation method,and the virulence of 4 chemical agents to Yam anthracnose was determined by mycelium growth rate method.The results indicate that the pathogen causing Yam anthracnose in the region is Colletotrichum gloeosporioides.The chemical agents of 5%hexaconazole SC,10%difenoconazole WG and 32.5%benzoyl-azoxystrobin SC had good antibacterial effect on the pathogen of Yam anthracnose,among which the pathogen of Yam anthracnose was most sensitive to 32.5%benzoyl-azoxystrobin SC,with its EC_(50) value of 0.0204 mg·L^(-1).This can provide reference for the prevention and control of anthracnose disease.