Quantitative estimation of aflatoxins produced by Aspergillus flavus in maize and their management

Isolates of Aspergillus flavus cultured from soil and seed samples of maize collected from different districts of Andhra Pradesh and Kolar district of Karnataka state were evaluated with potential fungal antagonist, Trichoderma viride isolate TIF-16 showed highest inhibition percentage (95.55) with high mycoparasitic activity. The seeds being colonized with A. flavus isolates were subjected to quantification of aflatoxins using High performance liquid chromatography (HPLC). The A.flavus isolate, AFT-16 produced highest B1 toxin level (4625.32 ppb) and AFT-19 produced highest B2 toxin level (5427.58 ppb), which are isolated from seed. From these studies, prevalence of both afB1 and afB2 toxins in one sample of infected maize kernels was documented. Treatment of maize plants with talc based formulation of T. viride significantly reduced A. flavus infection and production of aflatoxin in maize kernels. When the cobs were challenge-inoculated with A.flavus 3 days after application of T. viride, the aflatoxin content in maize kernels was decreased from 11.5 to 0.12 ppb.