Management of wilt disease of lentil through bio control agents and organic amendments in Rajasthan

Abstract

Lentil (Lens culinaris M) has gained importance in various parts of Rajasthan as potential pulses crop. This crop suffers from many diseases among which vascular wilt of lentil caused by Fusarium oxysporum f. sp. lentis, has become a thoughtful trouble in recent years in Rajasthan and in other lentil growing parts of India, resulting heavy yield losses. Systematic studies in laboratory, cage house and field trials were conducted (2016-17 to 2017-18) to controlling wilt of lentil. Laboratory experiments were carried out in Completely Randomized design with four replications and field trials were carried out consecutively during 2016-17 and 2017-2018 crop season in Randomized block design (RBD) with four replications using L9-12 a susceptible cultivar. In In Vitro, bio efficacy of selected bio agents, maximum 81.33 per cent mycelial growth inhibition of pathogen was recorded in Trichoderma harzianum (local isolate) and minimum mycelial growth inhibition 55.00 per cent was recorded in Bacillus subtillus. In In vivo condition, effect of selected bio agents and organic amendments on disease incidence, percent disease control, pathogen spore in per gram soil and yield ha-1 of lentil was recorded. Application of Trichoderma harzianum (Local isolate) @ 6g/Kg seed was found most effective with maximum seed germination 91.95 and 90.62 per cent, lowest disease incidence of 24.22 and 25.39 per cent and higher pooled mean grain yield 774.31 kg/ha over check during 2016-17 and 2017-18, respectively. Among organic amendments maximum disease control 42.02% per cent, minimum average disease incidence 36.33 per cent and minimum pathogen spores (1.3x104 per gram soil) were observed in neem cake amendment followed by poultry manure and Vermicompost amendments. This indicates that these treatments have significant role in biologically based management strategies for controlling Fusarium wilt disease under organic mode of lentil cultivation in Rajasthan