Identification Pathogen of Tobacco Seedling Wilt and Toxicity Test in Laboratory

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.