Efficacy of Trichoderma asperellum and mycorrhizal fungi against root rot disease (Macrophomina phaseolina) in sesame

Abstract

Sesame is liable to be infected by various pathogenic fungi like leaf blight and root rot at all the stages of crop growth. Therefore, the present study was carried out to evaluate the effect of bio agents on managing the diseases. Seed treatment with Trichoderma asperellum @ 4 gm/kg of seed + soil application of Trichoderma asperellum (2.5 kg/ha) mixed with FYM @150 kg and VAM 10 kg as basal application resulted in minimum root rot incidence (14.87) and maximum per cent reduction of disease over control. Population of Trichoderma from rhizosphere of soil from different treatments by dilution plating technique. From these soil samples, Trichoderma was isolated and estimated on TSM medium by using dilution 104. The number of colonies of Trichoderma was 38.30 x 104 CFU and 21.48 x 104 CFU/g of soil from T1 where as in T2 the population was 02.24 x 103 CFU, 05.89 x 103 CFU, 16.68 x 103 CFU and 11.70 x 104 CFU/g of soil at 40 and 80 days after sowing when compared to control which is recorded to 12.98 x 10 4 CFU and 5.42 x 104 CFU/g of soil. The population density of AM enumerated by wet sieving and decanting method from rhizosphere of soil from different treatments. The number of AM spores was maximum in T1 with 42.14 and 35.87/100g of soil as compared to control with 15.66 and 13.27/100g of soil. The maximum seed yield of 678 kg/ha was observed in the effective treatment; whereas minimum seed yield of 446 kg/ha was observed in the control.