Biofumigation based integrated disease management against Athelia rolfsii (syn. Sclerotium rolfsii Sacc.) induced collar rot disease of betelvine (Piper betle L.)

Collar rot of betelvine (Piper betle L.) is an important disease in India, caused by Athelia rolfsii (Curzi) C.C. Tu and Kimbr. (syn. Sclerotium rolfsii Sacc.) Management of this soil borne pathogen is highly challenging in the shade house (boroj) condition, where betelvine is grown as a perennial climber. As betel leaves are consumed raw, application of chemical fungicides is highly restricted to safeguard human health. The present study compared various integrated disease management packages by suitable combination of biofumigation, biocontrol and soil solarization strategies and evaluated the best package at farmers’ field condition. The treatment combination of “biofumigation with 0.7 kg m−2 green biomass of Indian mustard cv. Pusa Mahak” + “curing of soil by resting for 5 months in the form of heap followed by soil solarization for 30 days” + “biocontrol with 10 g m−2Trichoderma sp. T-Nam colonized whole rice grain” was found to be the most economical and effective disease management option with highest leaf yield in the experimental plot. This package resulted in 76.82% reduction in collar rot incidence, 29.94% increase in leaf yield and 41.45% increase in net income during March-June crop cycle, in farmers’ field condition, when compared to the Farmers’ Practice (soil drench with 4 L m−2 0.25% Blitox 50 W). Trichoderma was found to be highly tolerant to the biofumigation volatiles, which maintained a good soil population (32.78 × 103 CFU g−1 soil) in the farmers’ plots adopting integrated disease management. Biofumigation with Indian mustard and biocontrol with local isolate of Trichoderma offered an economical management of the collar rot disease in betelvine, without compromising the crop yield and the population of Trichoderma spp. in soil.