author(s)
Shahram Aramideh, Shahram Mirfakhraei, Abbas Hosseinzadeh, Akbar Ghassemi-Kahrizeh, Leila Eslampour, Sepideh Khalilolahi, Samira Mahinfar and Lachin Mokhtarnezhad

abstract
Distribution and diversity of cry genes in Bacillus thuringiensis isolates from different ecological regions of West-Azerbaijan province of Iran were studied. Determination of cry (cry1, cry2, cry3, cry4, cry7, cry9 and cry11) genes was based on polymerase chain reaction (PCR). Forty-eight strains were isolated from 744 different samples. Strains containing cry1 genes were the most abundant, 93.75%. B. thuringiensis strains harboring cry7 and cry2 genes represented 4.16% and 76.16% of the strains. Cry3, cry4, cry9, and cry11 genes were found in 50%, 45.83%, 12.68% and 18.75% of the strains, respectively. The 48 isolates were tested against Culex pipiens L., Plodia interpunctella (Hübner) and Tribolium confusum (Jacquelin du Val) larvae. Four isolates (8.33%) exhibited high toxicity against C. pipiens, 16 strains (30%) against P. interpunctella and 4 strains (8.33%) against T. confusem larvae.