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Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) is an invasive alien pest native to the Americas, and it was introduced in the state of Karnataka, India in the year 2018. They cause severe economic damage to the maize crop, which significantly decreases the quality and quantity of the crop's yield. The microbiota of fall armyworm could play important roles in their growth, development and environmental adaptation to their host plants or animals and not much is known about the microbiota of FAW in India. Even though bacterial communities in S. frugiperdaare inadequately studied, therefore, a study was undertaken on the microbial communities associated with the gut of S. frugiperda collected randomly from twelve different locations in the eastern part of India under laboratory conditions. The results revealed that the two bacterial phyla, namely, proteobacteria and firmicutes, were predominantly present in the larval gut of S. frugiperda. However, analyses at the genus level revealed that despite the high genus-level diversity between samples, there were 9 different genera observed. Interestingly, we found two bacterial genera, i.e., Kluyvera and Yokenella, which may be new findings from the eastern part of India and were not reported earlier from any other countries. On the other hand, analyses at the species level revealed that a total of thirty-three (33) species were found from the 12 samples of S. frugiperda collected from different locations. Among the 33 species, Enterococcusgroup genera were most abundant across the FAW gut samples collected, followed by Klebsiella sp. and Enterobacter sp. and a small proportion of Raoultella, Citrobacter, Leclercia and Pantoea.

Studies were taken up to monitor the seasonal occurrence of whitefly population in cotton as well as its insecticidal management under field conditions of Institutional Research Farm, Institute of Agriculture, Visva-Bharati, Sriniketan, during the kharif season of 2018-19. Population reduction of whitefly was done with eight insecticides having different molecular composition and one untreated check. The experiment was drawn in a Randomised Block Design with three replications. The occurrence of whitefly was noticed during the fourth week of July (0.2 whitefly per plant) which continued till late December. Highest whitefly population was found during fourth week of September (12.24 Whitefly per plant). Correlation studies of whitefly population and abiotic factors suggested that whitefly population was significantly correlated with maximum temperature at 1% level of significance. Among the different insecticides tested for population reduction of whitefly in Bt cotton it was noticed that combination product of Imidacloprid 6% + Lambda Cyhalothrin 4%SL @ 500 ml/ha and 450 ml/ha proved most effective and gave 94.15% and 93.81% pest population reduction after second spray imposition respectively.

A field study was undertaken in the Institutional Research Farm, Institute of Agriculture, Visva-Bharati, Sriniketan to evaluate the seasonal incidence and population variation of red cotton bug with respect to weather conditions and its insecticidal management during kharif, 2018-19. Experiments were conducted in a Randomized Block Design (RBD) with three replications having nine different insecticidal treatments including one untreated control. Red cotton bug population was recorded from Second week of August and continued till harvest with a peak population Peak population at Second week of November. Multivariate correlation studies showed that the red cotton bug population was significantly positively correlated with Temperature Gradient and significantly negatively correlated with Relative Humidity and Rainfall. Among the different insecticides tested combination of Imidacloprid 6% + Lambda Cyhalothrin 4% SL @ 500 ml/ha proved most effective and giving 71.14% and 94.84% pest population reduction in two consecutive treatment imposition.