Glass House Studies on Management of Groundnut Stem Rot using Trichoderma harzianum and Pseudomonas fluorescens

In the present investigation on “Efficacy of combined bioformulation of Pseudomonas fluorescens and Trichoderma spp. in the management of stem rot of groundnut”, six native rhizosphere isolates of Trichoderma spp. and five native rhizosphere isolates of P. fluorescens were isolated, screened for their biocontrol potential against Sclerotium rolfsii, incitants of stem rot of groundnut under in vitro condition. The potential isolates were further assessed in vivo in pot culture. Among six Trichoderma isolates tested, isolate GRT4 recorded highest mean inhibition (74.69%) followed by GRT2 (73.85%) which were on par with each other. Out of five isolates of P. fluorescens tested, isolate PF3 was superior with highest mean inhibition (40.93 %) which was significantly differed with the rest of the isolates. The efficacy of potential fungal antagonist Trichoderma isolate GRT4, bacterial antagonist PF4 was tested in pot culture against stem rot of groundnut. Among the twelve treatments imposed, treatment T10 i.e. seed treatment with P. fluorescens @ 10 g + Trichoderma spp. @ 8 g kg -1 of seed along with soil treatment with combined bioformulation @ 2 L + 80 kg of FYM + 5 kg of neem cake acre -1 was found to be superior as it recorded the highest germination percentage (93.33%), highest initial population (9.33), final population (8.33) and least per cent disease incidence of 11.11 per cent. This treatment also recorded maximum shoot length (25.28 cm), root length (30.79 cm) and maximum fresh and dry weights i.e. 11.35 g and 2.11 g, respectively when compared to other treatments.