controlling of aflatoxin B1 using Oyster fungus )Pleurotus ostreatus( in Basil plant (Ocimum basilicum

The study was carried out at Faculty of Agriculture, University of Kufa from March to August 2018 to detect the ability of Aspergillus flavus isolates to produce aflatoxin B1 and to determine the effect of Pleurotus ostreatus in reducing of Aflatoxin B1 produced by A. flavus. The results showed presente of three species of fungi including A. flavus, Aspergillus niger and Penicillium spp. It was found that there was a significant domunion of A. flavus followed by A.niger and Penicillium spp. Their frequency rates were 63.88%, 22.22% and 13.88%, respectively. However, appearance rates of these isolates were 70%, 40% and 20%, respectively. Ammonia detection test showed that there were 15 out of 23 isolates of A. flavus have ability to produce Aflatoxin B1, with a rate of 65.21%. However, layer chromatography (TLC) test showed only 10 out of 23 isolates of A. flavus were able to produce Aflatoxin B1, with a rate of 43.47%. The present results also showed that adding of P. ostreatus significantly affected the logarithmic number of A. flavus spores which was 5.74 (5.6 x 105spore / g) in the treatment of 5 ml A. flavus + 15 g P. ostreatus. In addition, P. ostreatus has capacity to reduce the Aflatoxin B1 produced by A. flavus. Spectrophotometer results showed that the treatments of 5 ml A. flavus + 15 g P.ostreatus, 10 ml A. flavus + 15 g P.ostreatusand 15 ml A. flavus + 15 g P.ostreatus significantly reduced the percentage of produced Aflatoxin B1 (84.5%, 84.4%, 88.3%), compared to the treatment of A. flavus + 10 g P.ostreatus which gave about 69.8% reduction rate