Molecular cloning of a new cry2A-type gene from Bacillus thuringiensis strain Nn10 and its expression studies.

In the present study, eight indigenous Bacillus thuringiensis isolates of Western Ghats of India with more than 90% toxicity against Helicoverpa armigera were characterized for cry2A gene sub families. Seven of the eight isolates harboured cry2Aa, cry2Ab and cry2Ac genes alone and or in combination. Further, the indigenous cry2Aa gene(s) from Bacillus thuringiensis isolate Nn10 which showed 100% mortality against Helicoverpa armigera was cloned and expressed into recombinant Bt strains for management of resistance development in insects.

Codon usage bias.

Codon usage bias is the preferential or non-random use of synonymous codons, a ubiquitous phenomenon observed in bacteria, plants and animals. Different species have consistent and characteristic codon biases. Codon bias varies not only with species, family or group within kingdom, but also between the genes within an organism.

A novel Bacillus thuringiensis isolate toxic to cotton pink bollworm (Pectinophora gossypiella Saunders).

In this study, we report a novel indigenous Bacillus thuringiensis (Bt) isolate, T26, which showed spores and crystals under scanning electron microscope and pathogenicity against the pink bollworm (Pectinophora gossypiella Saunders) in artificial diet based bioassay. SDS-PAGE analysis of the spore-crystal mixture of the Bt isolate, T26 revealed presence of three major protein bands of approximate molecular weights of 80, 55 and 40 kDa. The draft genome assembly consists of 56 scaffolds with an entire draft genome size of 5,054,095 bp.

Genome sequencing of Bacillus thuringiensis isolate T414 toxic to pink bollworm (Pectinophora gossypiella Saunders) and its insecticidal genes.

Bacillus thuringiensis is a spore-forming bacterium that is pathogenic towards a range of insect and nematode species and had been widely used as a biopesticide. In this study, we present the morphological, molecular and genetic characteristics of an indigenous Bt isolate T414 which displayed an effective toxicity against Pectinophora gossypiella. Scanning electron microscopy revealed the presence of bipyramidal, spherical and cubic shaped protein crystals in its spore-crystal suspension.

A new observation on feeding behaviour of pink bollworm and its application in screening -resistant population.

The pink bollworm (PBW), (Saund.) does not feed on leaves in natural circumstances. We made an attempt with the first instar larva (5 days old) and found it eats the leaf in the absence of other foods.