EFFECT OF SOME BIOAGENTS ON INHIBITING TOXINS PRODUCED BY ASPERGILLUS FLAVUS IN PEANUT PODS

Two different beneficial microorganisms namely Trichoderma harzianum and Bacillus subtilis were used under laboratory conditions to evaluate their antagonistic effects against Aspergillus flavus. T. harzianum and B. subtilis were formulated as powder each 1 gm contains 30x10^6 c.f.u, then used as pod dressing treatment to study their effect on inhibiting toxins produced by Aspergillus flavus during storage under room condition. Powder formula of both organisms was applied at three different rates and in three different numbers of application. These treatments were done with artificially infested peanut pods stored under room conditions for three months. Obtained data showed that both bioagents inhibit linear growth of A. flavus. T. harzianum gave better antagonistic effect and gave 77.7% reduction in linear growth whereas B. sublilis gave only 66.66%. All treatments reduced the different four types of Aflatoxins, produced by A. flavus in peanut pods. T. harzianum gave the best result in reducing the amount of toxins and 87.8% reduction in toxins production was observed whereas B, subtilis gave only 76.18% reduction compare with the control treatment. Positive correlation between storage periods of peanut pods and reduction of toxin was observed in case of treatment of peanut pods with both antagonistic agents. Regarding number of applications, treated peanut pods with T. harzianum once gave best result when compared with application for two or three times. On the contrary applying B. subtilis for two or three times showed more efficacy in reducing amount of toxins produced by A. flavus. Data also showed that dose of (20gm) T. harzianum or B. subtilis formula/1 kg of pods was the most effective dose in reducing the amount of toxins. Positive correlation between increasing period of storage up to three months and percentage of reduction in toxin producing by A. flavus was also noticed.