Effcacy of different biological control agents against major postharvest pathogens of grapes under room temperature storage conditions

Abstract

Grapes were treated post harvest with a variety of biological agents to determine their effcacy in reducing yield loss. The agents Pseudomonas, Bacillus, Trichoderma and yeast isolates were individually screened against a number of postharvest pathogens including Aspergillus carbonarius, Penicillum expansum, and Fusarium moniliforme. B. subtilis strains EPC-8 and EPCO-16 showed high mycelial growth suppression of A. carbonarius and P. expansum  in vitro. The fungal antagonist Trichoderma viride strain (Tv Tvm) was the most effective, inhibiting mycelial growth by 88.8 per cent. The biological control agents were tested in pre, post and combined inoculation studies against postharvest pathogens of grapes.  In the pre inoculation, B. subtilis (EPC-8) reduced the disease incidence of A. carbonarius causing rot, T. harzianum (Th Co) was effective against P. expansum, and T. viride (Tv Tvm) was effective against F. moniliforme. The same trend of effectiveness was also found in the post-inoculation and combined inoculation tests.