Distribution of cry and cyt Genes among Indigenous Bacillus thuringiensis Isolates with Mosquitocidal Activity

Autor(es): Mahalakshmi, Ayyasamy; Sujatha, Kabilan; Kani, Poornima; Shenbagarathai, Rajaiah


Resumo: Bacillus thuringiensis strains isolated from Madurai, TamilNadu, India were evaluated for their mosquitocidal activity, as well as cry and cyt genes diversity. It revealed that 99% of the parasporal crystal morphology of these isolates was spherical in nature and a variable percentage (0% - 100%) of toxicity was observed against Culex quinquefasciatus and Aedes aegypti. PCR analysis revealed that 53% of the isolates were positive for the various cry and cyt genes tested, whereas 47% did not produce any PCR product for the cry gene analyzed. Diverse pattern of cry and cyt genes distribution was observed even in the isolates from the same sample. B. thuringienis subsp. LDC-9 showed three-fold higher toxicity against Culex quinquefasciatus than that of B. thuringiensis var israelensis which might be used as a potential strain to control mosquitoes in near future after field evaluation.


Palavras-Chave: Biological control; Nucleotide sequence; DNA; Polymerase chain reaction; Pest control; Toxicity; Strains; Aquatic insects; Public health; CRY protein; Spore crystals


Imprenta: Advances in Microbiology, V. 2, n. 3, p. 216-226, 2012.


Descritores: Aedes aegypti - DNA ; Aedes aegypti - Proteins ; Aedes aegypti - Public health


Data de publicação: 2012