Vegetos

Abstract

The biocontrol fungi, Trichoderma spp. are the most important biocontrol agent and have been used extensively worldwide for the management of various plant pathogens. Twenty isolates of Trichoderma (T. harzianum, T. viride and T. hamatum) were isolated from rhizosphere of different crops and location of Andaman district, Andaman and Nicobar Island and tested in vitro against sclerotium rolfsii causing stem rot of brinjal. In vitro test of these antagonist against test pathogen under non-volatile condition revealed that all isolates significantly inhibited the S. rolfsii in vitro (>80% inhibition), but the isolates Th-CARI1 to Th-CARI5 was most effective in parasitizing the test pathogen with >90% inhibition. Under volatile condition there was a significant variation in the percentage inhibition (16.7% - 61%). PCR-RFLP amplified fragments with ITS1 and ITS4 primer of these isolates showed clear difference among the Trichoderma isolates with overall 69% similarity. However the Trichoderma isolates Thr-1, Tv-3, GH4-1 and Thr 1(2) were found 90% similarity.