Stimulating of Biodegradation of Oxamyl Pesticide by Low Dose Gamma Irradiated Fungi

Abstract

This investigation has been conducted to study the possibility of stimulating Trichoderma spp with low dose gamma radiation for biodegradation of Oxamyl pesticides. Fungi strains capable for biodegradation of oxamyl are identified as Trichoderma spp., including T. harzianum, T. viride, Aspergillus niger, Fusarium oxysporum and Penicillium cyclopium. The results indicated that Trichoderma spp. used Oxamyl as source of carbon and nitrogen and possesses enzyme(s), which acts on amide and ester bond in Oxamyl structure. Degradation of oxamyl was 72.5% within 10 days of incubation by T. harzianum strain. It is very important to note that degradation of oxamyl 82.05% within 10 days of incubation by T. viride strain. This indicated that the isolates of Trichoderma spp. were potentially useful for oxamyl bioremediation. The biomass of Trichoderma spp strain were increased and reached its maximum at 250 Gy by 21.97 and 40.0 when using Trichoderma spp., as well as T. viride, respectively. As a general trends the gamma radiation over than 0.25 KGr reduce the growth of Trichoderma spp by 50.27 and 38.13, using Trichoderma spp. as well as T. viride, respectively.