Identification of root rot pathogen in Hubei cigar tobacco

In order to clarify the pathogen causing root rot in Hubei cigar tobacco, diseased plant samples were collected from Danjiangkou, Enshi and Yichang regions, which are the main producing areas of Hubei cigar tobacco. The pathogen was isolated by conventional tissue isolation method, and its pathogenicity was verified by indoor inoculation of soil containing pathogen, and morphological identification and molecular biological identification were carried out. The results showed that the colonies of Fusarium on PDA medium were white to flesh-pink, and in some of them, the color deepened at a later stage and the mycelium was floccose. The conidia were typically sickle-shaped, the macroconidia were mostly septate, colorless, and sickle-shaped. Most of the microconidia were aseptate, elliptic or fusiform. Phylogenetic analysis based on ITS and EF-1α sequences identified Fusarium oxysporum and Fusarium solani as the main pathogens causing root rot in Hubei cigar tobacco.