Bioactive compound of antifungal metabolite from Trichoderma harzianum mutant strain for the control of anthracnose of chili (Capsicum annuum L.).

摘要

The antifungal metabolite was purified from a mutant strain of Trichoderma harzianum T-156-co5 by a chromatography procedure. The chemical constituent of the antifungal metabolite was determined by 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopy. The NMR spectroscopic data showed that the antifungal compound was closely related to isoharziandione. The purified antifungal metabolite at concentrations of 50 and 100 mg L-1 was tested for the inhibition of spore germination of Colletotrichum capsici, a causal agent of anthracnose on chili (Capsicum annuum L. var. annuum). The result showed that both concentrations gave high percentages of inhibition, with 100 mg L-1 providing the highest efficacy of 83.4% compared with control 2 (sterilized water). Purified antifungal metabolite at 100 mg L-1 was also comparable with 100 mg L-1 benomyl in controlling anthracnose on detached chili fruits. The treatment with 100 mg L-1 gave the highest disease control efficacy of 89.9% compared with control 2, whereas 88.5% disease inhibition was observed in chili fruits treated with 100 mg L-1 benomyl. Control 1 (2% methanol) treatment showed only 6.4% disease inhibition.