Berber, İsmetAtalan, EkremÇökmüş, Cumhur2014-09-032014-09-032004Berber, İ., Atalan, E., Çökmüş, C. "The Influence of Pesticides on the Spore Viability, Toxin Stability and Larvicidal Activity of Bacillus sphaericus 2362 Strain", Fresenius Environmental Bulletin, Vol.13, No: 5, pp.424-429.http://www.psp-parlar.de/pdf/F_23_195_pp424_429.pdfhttps://hdl.handle.net/11486/525In this study, 12 different commercial pesticides, in-cluding 5 fungicides, 5 herbicides, 1 aphicide and 1 acari-cide, were investigated for their effects on spore viability, toxin stability and larvicidal activity of a mosquito patho-genic B. sphaericus 2362 strain. Minimal inhibitory con-centrations (MICs) of each pesticide were determined after 48 h incubation of B. sphaericus 2362 strain. Ac-cording to MIC results, all pesticides showed various inhibitory effects on the growth of the test bacterium. Particularly, the pesticides which contain TCA, hymexa-zol, copper sulphate, hexythiazox, 2,4-D Amine, copper inhibited spore germination significantly and bacterial growth even at the lowest tested concentrations. Our re-sults indicated that various commercial pesticides in dif-ferent concentrations reduced the spore viability signifi-cantly and heat-resistant spore numbers of B. sphaericus 2362 strain. In general, the pesticides decreased the spore numbers 104-105-fold compared to initial ones. Further-more, it was observed that the larvicidal activity was completely lost when it was grown at the concentration of MIC values or higher. Indeed, SDS-PAGE analysis con-firmed that the binary toxin proteins, 41.9 kDa and 51.4 kDa, were lost at the MIC values and higher concentra-tions although parasporal crystals did not disappear in the much lower pesticide concentration.enPesticidesB. sphaericus 2362Toxin stabilityLarvicidal activity and SDS-PAGEArticle