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With the help of life table construction, which derives the net-reproductive rate, mean time of generation and the survivorship curve, one can classify the insects into pest or as non-pest. This pa...

Silverleaf whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most notorious invasive insect pests, infesting more than 900 species of plants and spreading more than 200 viral diseases. This polyphagous agricultural pest harbours diverse bacterial communities in its gut, which perform multiple functions in whiteflies, including nutrient provisioning, amino acid biosynthesis, and virus transmission. The present exploratory study compares the bacterial communities associated with silverleaf whitefly infesting cassava, also known as cassava whitefly, collected from two different zones (zone P: plains; zone H: high ranges), from Kerala, India, using next-generation sequencing of 16S rDNA. The data sets for these two regions consisted of 1 321 906 and 690 661 high-quality paired-end sequences with mean length of 150 bp. Highly diverse bacterial communities were present in the sample, containing approximately 3513 operational taxonomic units (OTUs). Sequence analysis showed a marked difference in the relative abundance of bacteria in the populations. A total of 16 bacterial phyla, 27 classes, 56 orders, 91 families, 236 genera, and 409 species were identified from the P population, against 16, 31, 60, 88, 225, and 355, respectively, in the H population. Arsenophonus sp. (Enterobacteriaceae), which is important for virus transmission by whiteflies, was relatively abundant in the P population, whereas in the H population Bacillus sp. was the most dominant group. The association of whitefly biotypes and secondary symbionts suggests a possible contribution of these bacteria to host characteristics such as virus transmission, host range, insecticide resistance, and speciation.

Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae), a polyphagous agricultural pest of global importance, harbour diverse bacterial communities in its gut. We analysed the composition and diversity of gut bacteria using Illumina Next-Generation Sequencing of 16S ribosomal RNA amplicons. The data set consisted of 864,813 high-quality paired end sequences with mean length of 150 base pairs. Highly diverse bacterial communities were present in the sample containing approximately 2303 operational taxonomic units (OTUs). A total of 17 bacterial phyla, 34 classes, 84 orders, 173 families, 334 genera, and 707 species were identified from the sequence analysis. Actinobacteria was the most dominant groups, followed by Proteobacteria and Firmicutes . The search on function of different gut inhabiting bacteria of H. armigera revealed their role in nutrition, detoxification of lethal insecticide molecules, and defensive action against pathogens. Insecticidal toxin producing bacterial species were also found associated with the H. armigera gut .