Relative antagonistic effect of different isolates of Trichoderma viride and T. harzianum against Phytophthora capsici - a bell pepper pathogen

Isolates of Trichoderma viride and T. harzianum were tested for their myco-parasitic ability and relative antagonistic effect that showed all the Trichoderma isolates inhibited significantly the growth of the pathogen and it ranged from 62.73% ( T. viride 1) to 45.37% ( T. viride PDBC TV 23). Germination per cent ranged from 78.8 ( T. viride 3) to 98.9 ( T. viride PDBC TV 23) when treated with bio-agents, whereas in pathogen check it was only 73.3%. Maximum vigor index (547.3) was recorded in T. viride (PDBC TV 23), whereas in pathogen check it was 84.7 only. Fungicide treatment exhibited almost equal disease incidence and in pathogen check, it was as high as 68.9%, while minimum (16.7%) plant mortality was recorded in seeds treated with T. viride 1. In fungicidal treatment 33% plant mortality was recorded while in pathogen check it was highest (46.7%). The results obtained clearly indicated that the efficacy of different isolates of the same species also showed variation when tested against the same pathogen. Therefore, it may be concluded that before application in the field the potentiality of every strain of the bioagents should be tested against the target pathogen.