Evaluation of Trichoderma spp. and Fungicides in the Management of Collar Rot of Gerbera Incited by Sclerotium rolfsii

An extensive study was undertaken to manage the most vigorous, polyphagous pathogen Sclerotium rolfsii causing collar rot disease in Gerbera by utilizing nine commercial fungicides and eight novel Trichoderma spp. Under in vitro conditions, there was 61.11 per cent reduction of pathogen (S. rolfsii) by T. harzianum NVTH2 and T. viride TV1 over control and was followed by T. citrinoviride NVTC1, T. citrinoviride NVTC2 and T. asperellum NVTA1 with per cent inhibition of 55.55, 54.44 and 53.33 respectively. On the other hand, commercial fungicides, tebuconazole 50%+ trifloxystrobin 25%, tebuconazole 250 EC, propioconazole 25% EC, fenamidone 10%+ mancozeb 50%WG and propineb 70WP reduced the growth of S. rolfsii to an extent of 100 per cent inhibition in all the tested concentrations. Combination of most effective Trichoderma spp. and fungicides had resulted in the best treatment T2 against the collar rot pathogen of Gerbera under protected cultivation