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Mosquitoes, Aedes aegypti L. and Anopheles gambiae G. are very important insect vectors for transmission of infectious diseases like dengue and malaria. Extensive use of insecticides provided rapid control of these insect vectors but gradually they have developed insecticide resistance. Target site insensitivity is one the main reasons for insecticide resistance development. Development of new insecticides targeting different target sites can be a useful approach for management of insecticide resistance in insect pests. Chorion peroxidase inhibitors have been predicted by using computer aided drug designing (CAAD) approach. 3D structure of chorion peroxidase of A. aegypti and A. gambiae was predicted by using I-TASSER and refined by 3Drefine and GalaxyWEB servers. Ligand binding sites were predicted by using 3DLigandSite, RaptorX and COACH servers. Ligands/Inhibitor compounds were obtained from literature and drug bank. Protein-ligand docking was performed by AutoDock Vina. The compounds with low binding energy and good interactions were selected for both species. Pharmacophore models were generated by using LigandScout. Screening of zinc library was performed against the features of designed pharmacophores. Top ten compounds with best pharmacophore fit score for each species were selected for docking with chorion peroxidase. Protein ligand interactions were determined through LIGPLOT. One lead compound showing lowest binding energy and best interactions was selected for each species, i.e., ZINC04581496 (A. aegypti) and ZINC15675298 (A. gambiae). Protein-Protein interaction was studied by STRING database to find the co-expressing proteins in network of chorion peroxidase. Ten interaction partners were found for A. aegypti while five for A. gambiae. These pharmacophore models may provide theoretical basis for designing effective insecticides for A. aegypti and A. gambiae control. The efficacy of computationally predicted lead molecules can be confirmed by testing in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Stored cereals and food products are severely infested by different insect pests throughout the world but Trogoderma granarium is found most destructive insect pest of stored grains. Temperature and relative humidity affects the growth and development of these insect pests of stored grains. Present study was designed to investigate the effects of temperature (20, 25 and 30°C) and relative humidity levels (55, 65 and 75%) on the efficacy of three synthetic Insect Growth Regulators (IGRs) i.e., pyriproxyfen, lufenuron and buprofezin at concentrations of 1, 5 and 10 ppm. The study aimed to estimate the fecundity and adult emergence inhibition of T. granarium under controlled laboratory conditions. Counted numbers of grubs were exposed to IGRs at different levels of temperature and relative humidity. F1 adult emergence results at 20°C; showed highest percent reduction in adult emergence (84.38, 70.65 and 79.94%) when exposed to lufenuron, buprofezin and pyriproxyfen treated diet, respectively. At 75% relative humidity lufenuron, buprofezin and pyriproxyfen caused 77.53, 80.00 and 80.32% reduction in adult emergence, respectively. Adults were exposed to IGRs at different temperature and relative humidity to evaluate the oviposition inhibition too. Percentage of reduction in fecundity (87.95, 80.45 and 70.55%) perceived after exposure to buprofezin, pyriproxyfen and lufenuron treated diet, respectively at 20°C was found highest. While 75% relative humidity reduced fecundity most effectively (86.73, 83.72 and 69.11%) when test insects were treated with buprofezin, pyriproxyfen and lufenuron, respectively. It is concluded that temperature and relative humidity significantly affected the activity of tested growth regulators which may lead to standardization of abiotic factors to gain maximum efficiency of IGRs in future. [ABSTRACT FROM AUTHOR]

Seven insect growth regulators (IGRs) (One juvenile hormone analogues [Pyriproxyfen 10.8EC], two ecdysone agonist [Tebufenozide 20SC, Methoxyfenozide 240SC] and four chitin synthesis inhibitor [Lufenuron 50EC, Flufenoxuron 10DC, Triflumuron 20SC, and Buprofezin 25%WP]) were tested under laboratory conditions against the larvae of Trogoderma granarium (Everts) and Tribolium castaneum (Herbst). Four concentrations of these IGRs (2.5, 5, 7.5, and 10ppm) were applied to observe their effects at 30±2°C and 65±5% r.h. after 7 and 14 days of treatment application. The overall results showed that all the tested IGRs showed significant larvicidal activity against the larvae of both T. granarium and T. castaneum. Results revealed that the highest larval mortality of T. castaneum was 77.30 and 83.54% with flufenoxuron followed by methoxyfenozide (70.40, 76.65%), pyriproxyfen (56.61, 62.86%) and lufenuron (53.16, 59.41%) at 7 and 14 days after treatment (DAT). The lowest mortality 42.81 and 49.06% was resulted in case of triflumeron treatment after 7 and 14 days, respectively. Similarly, In case of T. granarium the highest mortality was 66.96 and 73.20% due to the effect of flufenoxuron, and was lowest 32.47 and 38.72% where triflumeron was applied after 7 and 14 days, respectively. Results regarding the comparative effect of different concentrations showed that highest mortality 65.23% in T. castaneum and 54.88% in T. granarium larvae was noted at 10 ppm and mortality was lowest at 2.5 ppm against both the test insects. Bioactivities of all the tested IGRs were found to be dose and exposure period dependent. The results regarding the relative potency of the entire tested IGRs indicated that they were more effective when applied on wheat as compared to rice and maize. From these results, it is concluded that the applications of IGRs have proved to be very effective against both species examined in the present study. These compounds particularly chitin synthesis inhibitors (CSIs) (flufenoxuron and lufenuron) should be considered as potential components in IPM of stored grains insect pests. [ABSTRACT FROM AUTHOR]