2021年春季,从湖南省怀化市中方县正清制药青风藤基地和湖南农业大学试验基地分别采集青风藤叶枯病病叶,利用组织分离法获得病原菌,并进行柯赫氏法则验证。借助形态学鉴定和分子系统学分析,明确青风藤叶枯病病原为交链隔孢(Alternaria alternata)。利用菌丝生长速率法对5种药剂(95%苯醚甲环唑、98%咪鲜胺、96%己唑醇、96.5%丙硫菌唑、98%嘧菌酯)进行筛选,结果显示95%苯醚甲环唑抑菌效果最好,EC50为0.043 6 mg/L;98%嘧菌酯抑菌效果最差,EC50值为8.447 3 mg/L。
In the spring of 2021, the Caulis sinomenii leaves with leaf blight were collected from the Zhengqing Pharmaceutical Base in Zhongfang County, Huaihua City, Hunan Province, and from the experimental farm of Hunan Agricultural University. The pathogen was isolated by tissue separation method and verified by Koch’s rule. The pathogen was identified as Alternaria alternata(A. alternata) by morphological and molecular phylogenetic identification. The mycelium growth rate method was used to determine the inhibition effect of 5 agents(95% Difenoconazole, 98% Prochloraz, 96% Hexaconazole, 96.5% Prothioconazole and 98% Azoxystrobin) to the pathogen, and the result showed that 95% Difenoconazole exhibited the best inhibitory effect with the EC50 of 0.043 6 mg/L, while 98% Azoxystrobin has the worst control effect with the EC50 of 8.447 3 mg/L.