author(s)
Mahadeva Swamy HM, Selvakumar G, Asokan R, Nagalakshmi G, Soumya BR and Abraham Verghese

abstract
A new full-length Bacillus thuringiensis cry1I type gene was isolated from the mango leaf webber (Orthaga exvinacea) that was naturally infested. And its sequence of nucleotides was determined. The new Cry1I protein's deduced amino acid sequence is identical with Cry1b (94%) and Cry1Ia (89%) toxins. NCBI GenBank's accession number was given to the nucleotide sequence of the new cry1I gene: KJ437512 (partial) and KJ437513, showing 93-99 percent homology with Cry1I toxins genes previously published. Bt_MLB_Cry1I 3D toxin homology model was developed, despite low sequence identity with its structural homologues, Cry1I not only resembles the previously reported Cry toxin structures but also shares the typical five conserved amino acid residue blocks and subsequently evaluates the 3D model using bioinformatics tools. Mixtures of spores/inclusions of the Bt-_MLB_Cry1I were tested for their toxicity against adults of brinjal ash weevil Myllocerus subfasciatus (Coleoptera: Curculionidae). In accordance with standard reference strains, adult mortality rates caused by spore and crystalline inclusion are 100 percent. The observed 100% mango leaf webber infestation to Bt in natural condition is a rare report indicating naturally high strain anti-lepidopterone activity. The increase in the number of Bt collections has resulted in an increase in the discovery of new Bt isolates with insecticide activity against a variety of insects or with increased insecticide activity. The current study has extended the potential for the management of Coleopteran pests to collect promising Bt isolates from naturally infected insect pests from different origins.