Performance evaluation of a novel dustable powder formulation of Trichoderma viride for seed treatment against Fusarium wilt in chickpea

摘要

Fusarium wilt is a devastating fungal disease of chickpea responsible for severe yield losses. Products for biological control present a preferred option to combat with this disease but suffer due to quality issue. In the present work, composition of a novel dustable powder for seed treatment containing Trichoderma viride spores (DS2) was optimized assessed w.r.t. physicochemical properties and bio-efficacy in vivo against Fusarium oxysporum f. sp. ciceris . Dual culture assay based screening of five strains of T. viride namely, ITCC 6889, ITCC 7204, ITCC 7764, ITCC 7847, ITCC 8276 revealed the highest potency (91.16 inhibition) of ITCC 7764 strain, which was used as the active ingredient biomass for development of the dustable powder formulation for dry seed treatment (DS) (1 w/w). Physico-chemical characteristics using standard (CIPAC) methods registered the free flowing character of the optimized formulation (DS2) with slightly acidic character (6.50) and apparent density of 0.732 g cm~(−3). In-vivo bio-efficacy assessment of the DS formulation as chickpea seed coat revealed significant inhibitory influence of DS2 on the growth and development of the pathogen. The germination of DS2 treated seeds was superior at all the test doses relative to the commercial fungicide and the talc based T. viride formulation. The highest germination percentage was recorded in case of DS applied at RD with nominal value of 93.33, as compared to 80.33 and 83.33 in case of carbendazim and talc based formulations respectively. The percent wilting incidence of chickpea plants in DS treatment was 3.33, 6.67 and 13.33 at recommended, double of recommended and 1/2 of recommended dosages of DS2, respectively, the damage being significantly lesser than that in the commercial fungicide carbendazim (50WP) as well as the talc formulation (2 Dust) treatments.