Prevalence and Pathogenicity of the Isolates of Fusarium oxysporum f.sp. lentis in Different lentil Grown Areas of Uttarakhand and Uttar Pradesh

Abstract

Background: Different lentil-growing regions in India have reported that the lentil wilt poses a serious threat to crop cultivation because it can result in 100 percent crop losses. The fungus Fusarium oxysporum f.sp. lentis is the pathogen responsible for the disease. This infection is carried through the seed and soil. Methods: To understand the current status of the wilt pathogen in the total of twenty-two lentil-growing areas in Uttarakhand and Uttar Pradesh, the present study was conducted over the course of the two consecutive years 2017-18 and 2018-19, to track the incidence and prevalence of the disease. Observations were made on the numbers of diseased plants and number of infected fields to record incidence and prevalence of the lentil wilt, repectively. Moreover, twenty two isolates were collected to examine the different spores, pathogenicity levels and degree of correlation between both of them. Result: The data showed that the pathogen was present in every area at 100 per cent prevalence, with a disease incidence within 6.22-26.25 per cent. Data derived from 100 per cent availability of the pathogen inoculum in all lentil-growing regions over the course of two years predicts the emergence of the wilt disease threat to the crop. The observations indicate that the pathogen’s inoculum level had increased as the incidence of the disease increased during the subsequent crop season. It was also observed that spore size somewhat affects the pathogenicity of the isolates.Therefore the present study was conducted to observe the impact of wilt pathogen on different lentil grown areas and to alarm the farmers about this emerging threat.