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Domain swapping and generation of chimeric insecticidal crystal protein is an emerging area of insect pest management. The lepidopteran insect pest, gram pod borer (Helicoverpa armigera H.) wreaks havoc to chickpea crop affecting production. Lepidopteran insects were reported to be controlled by Bt (cryI) genes. We designed a plant codon optimized chimeric Bt gene (cry1Aabc) using three domains from three different cry1A genes (domains I, II, and III from cry1Aa, cry1Ab, and cry1Ac, respectively) and expressed it under the control of a constitutive promoter in chickpea (cv. DCP92-3) to assess its effect on gram pod borer. A total of six transgenic chickpea shoots were established by grafting into mature fertile plants. The in vitro regenerated (organogenetic) shoots were selected based on antibiotic kanamycin monosulfate (100 mg/L) with transformation efficiency of 0.076%. Three transgenic events were extensively studied based on gene expression pattern and insect mortality across generations. Protein expression in pod walls, immature seeds and leaves (pre- and post-flowering) were estimated and expression in pre-flowering stage was found higher than that of post-flowering. Analysis for the stable integration, expression and insect mortality (detached leaf and whole plant bioassay) led to identification of efficacious transgenic chickpea lines. The chimeric cry1Aabc expressed in chickpea is effective against gram pod borer and generated events can be utilized in transgenic breeding program.

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Field experiments were carried out in pigeonpea during Kharif 2014 to Kharif 2017 for Maruca vitrata Fabricius management through farmscaping approach with 7 different border crops (5 leguminous crops; 2 non-leguminous crops) and a sole crop. The M. vitrata larval webbing per plant was lowest and per cent decrease in webbing/plant over sole crop was highest in sorghum (2.05 and 60.95) as border crop followed by pearl millet (3.29 and 37.39). The highest mean number of Coccinella septumpunctata per plant (0.77), Cheilomenes sexmaculata per plant (0.85/plant) and spiders (0.76/plant) was recorded from sorghum as border crop with pigeonpea. The highest percent increase in above said natural enemies over sole crop was also recorded from sorghum as border crop treatment (755.6, 844.4 and 660). The highest pigeonpea yield (730.72 kg/ha) and per cent yield gain (65.81%) was also recorded with sorghum treatment. Among 5 weather parameters tested, day length (1.53) and relative humidity (-0.12) were found to influence the M. vitrata population significantly and its incidence was recorded from 41st SMW to 47th SMW.

Climate change is inflicting a huge impact in all the corners of biosphere. The insects, one of the early inhabitants of the biosphere are well known for their co-evolution with the plants and adaptation to the diverse environments. The power of flight makes the insect community to occupy new habitats and hence insect migration is one of the predominant areas for investigation in the perspective of climate change. The insect migration is a complex science that involves thorough understanding of insect bio-ecology along with knowledge of meteorology, aerodynamics, remote sensing and climatology. The various abiotic parameters that influence the insect migration and the effects of these parameters under the changing climatic scenario are discussed in this paper