Race profiling of Fusarium oxysporum f. sp. lentis causing wilt in lentil

Abstract

Lentil wilt caused by Fusarium oxysporum f. sp. lentis (Fol) is prevalent in lentil growing areas worldwide including India. Eighty-nine lentil genotypes were screened during 2012–2013 against virulent isolate of the pathogen (FLS 75) to constitute a set of differential cultivars for race/pathotype determination. The wilt incidence was highly variable ranging from 6.7 to 92.9% and 7 genotypes were found resistant, 3 moderately resistant and remaining were susceptible. Considering the reactions, genetic background and area of cultivation, 10 genotypes namely, JL 3, L 4149, PL 4, PL 101, DPL 62, K 75, MC 6, L 6183, Sehore 74-3 and Vidhokar local were selected as differential cultivars for race/pathotype profiling. The virulence of 50 Fol isolates was analysed on these differentials in 2013–2014 and 2014–2015. The isolates belonging to different regions of the country showed marked variability with respect to incidence ranging from 0 to 100% but the reaction patterns were more or less same in both the years. Based on the resistant and susceptible reactions on the differential cultivars, the isolates were grouped into eight races/pathotypes and differential cultivar for each race/pathotype was identified. Apart from standardizing a set of differential cultivars for Fol, the present study also reported the existence of races of Fol from India which was lacking earlier which will benefit in developing race specific wilt resistant lentil cultivars and help in identification of races/pathotypes prevalent in other lentil growing countries around the world.