Evaluation of biocontrol potential of some fungal decomposers of Sesbania aculeata L. Green manure against some soil-borne plant pathogens

Abstract

Aim: Soil borne phytopathogens are one of the major concern of today's agricultural system. In the present study, dominant fungal decomposers were selected and their potential as biological control agents was evaluated against some soil borne plantpathogens. Methodology: Effect of green manure amendment on the sclerotia viability of three soil-borne plant pathogens viz., Sclerotium rolfsii, Rhizoctonia solani and Sclerotinia sclerotiorum, effect of fungal decomposers on soil-borne phytopathogens in dual culture, effect of volatile and non-volatile metabolites of dominant fungal decomposers on the radial growth and sclerotia production of test pathogens were evaluated. Results: Green manure amendment resulted in reduced in sclerotia of S. rolfsii, R. solani and S. sclerotiorum by 40, 36 and 36.50%, respectively. In dual culture, the maximum growth inhibition of S. rolfsii, R. solani and S. sclerotiorum with Trichoderma harzianum were 49.95, 47.62 and 57.83%, respectively The maximum inhibition of S. rolfsii and S. sclerotiorum caused by the volatile metabolites produced by Trichoderma harzianum were 56.64 and 43.95%, whereas the maximum inhibition of R. solani was caused by volatile metabolites of Penicillium citrinum (44.96%). The maximum inhibition of S. rolfsii, R. solani and S. sclerotiorum through non-volatile metabolites of Trichoderma harzianum were 51.04,57.30 and 49.10%, respectively. The maximum reduction in sclerotia of S. rolfsii, R. solani and S. sclerotiorum with Trichoderma harzianum were 86.44, 88.54 and 88.20% respectively, under dual culture after 21 days of incubation. The maximum reduction in sclerotia of S. rolfsii, R. solani and S. sclerotiorum with Trichoderma harzianum were 95.42, 93.60 and 91.32%, respectively, under the effect of volatile metabolites after 21 days of incubation. The maximum reduction in sclerotia of S. rolfsii, R. solani and S. sclerotiorum with Trichoderma harzianum were 87.46, 79.74 and 85.10% respectively, under the effect of non-volatile metabolites after 21 days of incubation. Interpretation: All eight fungal decomposers effectively contribute in controlling the soil borne phytopathogens. Overall T harzianum, Aspergillus niger and Penicillium citrinum proved as potential bio-control agents against all soil borne plant pathogens viz., S. rolfsii, R. solani and S. sclerotiorum. © Triveni Enterprises, Lucknow (India).