Detection of Multiple Cry Genes in Bacillus thuringiensis Isolated from Different Soil Types in Zaria
A. Bello *
Department of Microbiology, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria.
I. M. Hussaini
Department of Microbiology, Faculty of Life Sciences, Ahmadu Bello University, Zaria, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Aims: To isolate and characterize Bacillus thuringiensis from different soil types within Zaria and screen them for the possession of cry genes.
Methodology: Soil samples were collected from different sites in Zaria. A total of twelve Bacillus thuringiensis strains were isolated from the different soil types. This isolates screen for the possession of cry1, cry2, cry3 and cry4 genes using Polymerase Chain Reaction.
Results: Eight of the 12 isolates showed the presence of at least one cry gene, while the remaining four showed none. Cry1 was the most frequently detected gene (58.88%), followed by cry2 (16.67%), while cry3 and cry4 had the least occurrence (8.33%). Isolate L3 had cry1 and cry2, L2 had cry1 and cry3 while isolate L1 had cry2 and cry4.
Conclusion: Bacillus thuringiensis isolates from different soil types in Zaria harbor possess cry genes and as such are potential biocontrol agents. The presence of multiple cry gene in one isolate is of entomological importance as it could have broad spectrum of toxicity against different pests.
Keywords: Cry gene, Bacillus thuringiensis, entomology, toxicity, biocontrol