烤烟苗期枯萎病原菌鉴定及室内药剂毒力测定

Identification Pathogen of Tobacco Seedling Wilt and Toxicity Test in Laboratory

摘要: 为了解贵州安龙烤烟苗期枯萎病原菌种类，筛选防治该病害化学药剂，采用组织分离法对贵州安龙烟苗枯萎病发病组织进行病原分离，结合形态特征、rDNA-ITS序列比对鉴定病原菌，并进行致病性测定。选用6种药剂，采用生长速率法测定供试药剂对病原菌菌丝抑制率。结果表明，芬芳镰孢（Fusarium redolens）为引起烤烟枯萎病的病原菌；室内毒力测定表明，40%氟硅唑EC、42.4%唑醚·氟酰胺SC对烤烟枯萎病菌菌丝生长有较好的抑制作用。

Abstract: This paper identified the pathogen of tobacco seedling wilt occurred in Anlong County Guizhou Province in 2016 and screened fungicides for the control of the disease. The pathogen of tobacco seedling wilt was isolated by tissue separation method and identified by morphological characteristics and sequence analysis of the internal transcribed spacer region of the ribosomal DNA (rDNA-ITS). The pathogenicity of pathogen was determined. The growth rate method was used to determine the inhibition rate of mycelia on the pathogen by using 6 kinds of fungicides. The results showed that Fusarium redolens was the pathogen of tobacco seedling wilt. Laboratory virulence test showed that 40% flusiazole EC and 42.4% pyraclostrobin·fluxapyroxad SC could inhibit the mycelia growth of the pathogen.