Phenotypic and Pathogenic Variability in Fusarium Wilt Pathogen Isolated from Bundelkhand Region.

Abstract

Fusarium wilt is one of the most severe disease of chickpea crop caused by Fusarium Oxysporum f. sp ciceri (FOC). Which is a soil born pathogen and can stay for prolonged period in soil even in absence of favourable conditions. Moreover many research reports have been observed showing a great variation in Fusarium pathogenicity among pathogen isolates from chickpea rhizosphere. Because of which identification of pathogenic and non-pathogenic strains of wilt pathogen has been a big challenge so far and, has been difficult in development and selection of resistant variety for fusarium wilt management strategies. The possible solution is to study phenotypic and pathogenic variability in the Fusarium pathogen. Therefore, in the current research FOC isolates, isolated from two districts of Bundelkhand region and studied their phenotypic and pathogenic variability. Colony characteristics of Fusarium wilt pathogen such as shape, margin, texture etc. were observed for FOC identification. To study the phenotypic and pathogenic variability, FOC isolates were categorised based on the culture pigmentation and further tested their pathogenicity. Pigmentation of FOC isolates have a wide range includes cottony white, white with ting of orange and white with violet and pale-yellow pigmentation. Macro and microconidia with resting spores (Chlamydospores) were also observed. Pathogenic variability of FOC isolates was measured by pathogenicity test on JG-62 cultivar. Total seventeen FOC isolates were studied, Out of which five FOC isolates were found highly pathogenic, whereas only one isolate was found weakly pathogenic, rest FOC isolates were moderately pathogenic. Hence our results confirmed that all the isolates of Fusarium Oxysporum f. sp. ciceri have reported great variation in their both phenotypic as well as pathogenic variability, and the results are steppingstone for further building research in breeding and management strategies of fusarium wilt.