Antifungal activity of propyl disulphide from neem against Lasiodiplodia theobromae and Neofusicoccum parvum causing stem end rot in mango.

Abstract

To investigate the antifungal effect of the neem extract volatile propyl disulphide against the fungal plant pathogens. Postharvest pathogens were isolated and identified as Lasiodiplodia theobromae and Neofusicoccum parvum causing the stem end rot of mango fruit. Antifungal activity of propyl disulphide at different concentrations was determined in comparison with ethanol and distilled water. Both diffusion assays were effective in controlling the mycelial growth of the tested fungi. The high coefficient of determination (R2 , 0·970-0·997) of the growth curves indicated the good fit of the experimental data to the Gompertz growth model. Propyl disulphide significantly (P≤0·05) decreased the mycelial growth during the stationary phase (A) and increased the lag phase (λ) than both control (ethanol and distilled water). This compound can potentially be applied to other tropical and subtropical fruits for the successful control of postharvest losses of fresh produce. This is the first report of propyl disulphide from neem extract against plant pathogens and could be beneficial for effective microbial decay prevention in food industries.