Ramasamy Asokan

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The cotton bollworm, Helicoverpa armigera is a highly polyphagous pest infesting a number of economically important crops, annually causing enormous crop losses. Management of this pest is challenging over the years due to various factors including development of resistance to wide spectrum of chemical insecticides. RNA interference (RNAi) has tremendous(More)
Characterization, direct sequencing of the PCR amplicon and phylogenetic relationship was done to discover a novel Vip protein genes of the Bt isolates, to improve the prospects for insect control, more Vip proteins should be sought out and researched to predict their insecticidal activity. Characterization was based on direct sequencing of PCR amplicon(More)
The Western Ghats of Karnataka natural ecosystem are among the most diverse and is one of the eight hottest hotspots of biological diversity in the world, that runs along the western part of India through four states including Karnataka. Bacillus thuringiensis (Bt) strains were isolated from soils of Western Ghats of Karnataka and characterized by molecular(More)
Bacillus thuringiensis (Bt) strains were isolated from soil samples of Great Nicobar Islands, one of the “hottest biodiversity hotspots,” where no collection has been characterized previously. The 36 new Bt isolates were obtained from 153 samples analyzed by crystal protein production with light/phase-contrast microscopy, determination of cry gene profile(More)
The nucleotide sequence of M- and S-RNA segments of an Indian iris yellow spot virus (IYSV) were determined. Sequence comparisons showed that both of these sequences shared less than 95 % identity with those other known IYSV isolates. Phylogenetic analysis revealed that the S- and M-RNA sequences of known IYSV isolates clustered with those of the(More)
Reverse-transcription quantitative real-time PCR (RT-qPCR), a sensitive technique is being extensively employed in quantification of gene expression. However this requires normalization with suitable reference gene (RG) which is crucial in minimizing inter sample variations. Information regarding suitable RG is scarce in general and more so in insects,(More)
Applications to combat non-lepidopteran insects are not as common as applications against lepidopteran insects. The aim of the present work was to isolate and identify Bacillus thuringiensis isolates from soil samples using five approaches, viz., analysis of crystal protein production by microscopy; detection of cry gene content by PCR, SDS-PAGE profiling;(More)
Surveys were conducted between 2010 and 2013 in west coast and east coast belts of India for major sucking pests, Helopeltis spp. in cashew. It reveals that three species viz., H. antonii Signoret, H. bradyi Waterhouse and H. theivora Waterhouse spread over different host plants. H. antonii was noticed as the predominant species and collected from 14(More)