The present work was aimed to study the synthesis of silver nanoparticles (Ag NPs) using Tri-Sodium Citrate (TSC), stability study of synthesized Ag NPs and their characterization. Synthesis of Ag NPs has been carried out by maintaining different conditions such as TSC concentration (0.50, 1.00 and 1.50%), AgNO3 concentration (0.50, 1.00 and 1.50 mM) and stirring time (10, 15 and 20 min). The stability study of synthesized Ag NPs conducted for 30 days without adding any stabilizing agents. The characterization of synthesized Ag NPs was carried out for different parameters like particle size and zeta potential using particle size analyzer, absorbance peak by UV-Visible spectrophotometer, morphology by Scanning Electron Microscope (SEM), crystallinity by X-Ray Diffractometer (XRD) and material structural characteristics by Atomic Force Microscope (AFM). The stable chemically synthesized Ag NPs were obtained at C20 (AgNO3 concentration of 1.5 mM, TSC 1.5% and stirring time 20 min) (desirability 99.97%), with average particle size of 22.14 nm and average absorbance peak of 449.85 nm.

Parasitoids have the potential to suppress populations of their hosts and thus may play an important role in influencing the temporal and spatial dynamics of pest arthropods. Behavioural interactions between foraging females, collectively constituting 'mutual interference', can reduce host suppression. We use laboratory microcosms to assess the prevalence and consequences of mutual interference behaviour in a bethylid wasp, Goniozus nephantidis (Muesebeck) (Hymenoptera: Bethylidae), which is known to brood guard and to engage in agonistic contests for individual hosts and which is also an agent of biological pest control. We hold host and parasitoid numbers constant and vary the degree of female-female contact that can occur. Mutual interference is manifest in a considerable reduction in the number of offspring produced when females are not fully isolated from each other, due to effects operating at the early stages of offspring production. This mutual interference may contribute towards the limited degree of host population suppression achieved when some species of bethylids are deployed as agents of biological pest control and also has clear potential to influence the efficiency of mass rearing of parasitoids prior to field release.

Climate change in terms of increase in atmospheric carbon dioxide and temperature has impact on agriculture including insect pests that minimize the crop yields. To address these impacts, biological studies on aphid, Aphis gossypii Glover on Bt cotton was conducted for six generations during 2013-14 and 2014-15 under different climate change conditions. The results revealed that the biometry of aphid was influenced by increased carbon dioxide (550 ppm CO2) and temperature (rise in 2°C of the prevailing temperature). This was evidenced by decrease in nymphal developmental time (3.67 ± 0.21 days), longevity of adult (9.43 ± 0.41 days), increased fecundity (32.46 ± 0.95) and reduced life cycle (12.28 ± 0.23 days) in the elevated conditions (both 550 ppm CO2 with 32°C as well as in 550 ppm CO2 + 34°C). However, morphometry of aphid showed slight variations in all the treatments but, aphids under elevated conditions showed reduced body size which indicated that the fitness of aphid was effected in the enriched carbon dioxide (CO2) and temperature conditions.

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Biodiversity of stored grain insects is often neglected as many of the workers think that it has limited or no diversity as consumer tolerance towards insect pests in stored grains is zero. Survey was conducted in six districts of HyderabadKarnataka region to find out the diversity and insects infesting major stored pulses during 2014-15. Callasobruchus analis L., C. maculates F., C. chinensis L. and T. castaneum H. were insect pests observed in collected pulse samples. Dinarmus basalis R., D. vagabundus T.,Dinarmus sp. and Uscana sp. were the hymenopteran parasitoids on pulse beetle collected from the samples. Rank abundance showed that C. analis was dominant species found on stored pulses.

Entomopathogenic fungi viz. Metarizhium anisoplae and Beauveria bassiana are well characterized in respect to pathogenicity to several insects and have been used for biological control of agriculture pests worldwide. Despite their potential, several factors like low resistance to elevated temperature have hindered widespread adoption of fungi as part of biological control regimes. In this study, five isolates of B. bassiana (Bb 01, Bb 02, Bb 03, Bb 04 and Bb 05) and two isolates of M. anisoplae (Ma 01 and Ma 02) were evaluated for thermotolerance capacity and bioefficacy against third instar of Spodoptera litura. Among the isolates studied, Bb 04 recorded the higher temperature tolerance up to 34oC with mean spore germination of 35.00 percent and mean dry mycelial weight of 443.38 mg. Further, in the bioassay studies, Bb 04 caused significantly (@ P<0.01%) higher percent mortality of S. litura larva at 1×108 spores ml-1 on fifth day (80.00 %) with LT50 value of 4.08 days and LC50 value of 2.07×104 conidia ml-1 at five days. Investigation results indicated that BB 04 is a suitable EPF isolate for management of S. litura where higher temperature prevails.