عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Native Bacillus thuringiensis (Bt) strains were isolated from forest soils samples of different regions in Mazandaran province and some encoding genes (Cry1) for insecticidal crystal proteins were detected in the isolated Bt strains. A total of one hundred forty four Bacillus strains were isolated from 32 soil samples using selective inhibitory property of sodium acetate. Insecticidal crystal proteins were detected in 32.63% of the isolates following colonies culturing, specific staining and microscopic identification. Cry1 gene was recognized in seven isolates as consequence of molecular analysis of the strains. Gene content investigation was carried out to detecting four Cry1A (Aa, Ab, Ac and Ad), Cry1B, Cry1C, Cry1D, Cry1E, Cry1F, Cry1G, Cry1H, Cry1I, Cry1J and Cry1K genes by using 14 specific primers. Cry1Ac and Cry1I genes were detected in all isolates, but Cry1Aa, Cry1E and Cry1G were not found in all isolates. Based on the results, the described molecular procedure can be exploited for identification of the insecticide-proteins encoding genes.