The efficacy of plant extracts (neem tree, Azadirachta indica A. Juss.; Meliaceae) and copepods [Mesocyclops aspericornis (Daday)] for the control of the dengue vector Aedes aegypti L. was tested in the laboratory. Neem Seed Kernel Extract (NSKE) at 25, 50, 100, 200 and 400 ppm caused significant mortality of Ae. aegypti larvae. Lethal concentrations (LC 50 and LC 90 ) were worked out. The LC 50 and LC 90 values for I to IV larval instars were 111.98, 138.34, 158.93, 185.22 ppm and for pupae was 146.13 ppm, respectively. The LC 90 value of I instar was 372.95 ppm, II instar was 422.77 ppm, III instar was 440.63 ppm, IV instar was 456.96 ppm, and pupae was 476.92 ppm, respectively.A study was conducted to test the whether the predatory efficiency of copepods on first instars changed in the presence of NSKE. The percentage of predatory efficiency of copepod was 6.80% in treatments without NSKE and the percentage of predatory efficiency increased up to 8.40% when copepods were combined with NSKE. This increase in predation efficiency may caused by detrimental effects of the neem active principle compound (Azadirachtin) on the mosquito larvae. Our results suggest that the combined application of copepods and neem extract to control Aedes populations is feasible. Repeated application of neem does not cause changes in copepod populations, because neem is highly degradable in the environment.

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Mosquitoes are the most critical group of insects in the context of public health, since they transmit key parasites and pathogens, causing millions of deaths annually. Culex tritaeniorhynchus is an important vector of Japanese encephalitis (JE) across urban and semi-urban areas of Asia. In this study, we bio-fabricated silver nanoparticles (Ag NP) using the leaf extract of Bougainvillea glabra as reducing and stabilizing agent. The synthesis of Ag NP was confirmed analyzing the excitation of surface Plasmon resonance using ultraviolet–visible (UV–vis) spectrophotometry. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed the clustered and irregular shapes of Ag NP. The presence of silver was determined by energy dispersive X-ray (EDX) spectroscopy. Fourier transform infrared (FTIR) spectroscopy analysis investigated the identity of secondary metabolites, which may act as Ag NP capping agents. The acute toxicity of B. glabra extract, synthesized Ag NP and a combined treatment testing blends of both mosquitocidals was evaluated against larvae and pupae of Cx. tritaeniorhynchus.B. glabra showed LC50 of 198.93 (larva I), 234.50 (II), 309.18 (III), 371.69 (IV) and 466.09 (pupa) µg/ml, Ag NP LC50 ranged from 7.77 (I) to 19.44 µg/ml (pupa). Combined treatments with B. glabra leaf extract plus 5.12.5 µg/ml of Ag NP lowered the botanical LC50 to 66.09 (I), 76.48 (II), 99.02 (III), 133.43 (IV) and 179.74 µg/ml (IV), respectively. The effectiveness of green-fabricated Ag NP against the JE vector was confirmed in adulticidal tests, as well as evaluating the impact of Ag NP on fecundity and longevity of adult mosquitoes. Lastly, the larvicidal effectiveness of Ag NP was confirmed in the field, treating sewage water bodies. Overall, this study suggests that the green-synthesized Ag NP fabricated using B. glabra can be considered a potential mosquito control device against the JE vector, C. tritaeniorhynchus in Asian regions

-Laboratory study has been conducted on the bioactivities of entomopathogenic nematodes and neem seed kernel extract (NSKE) against worker termites of Reticulitermes flavipes. Neem at various concentrations did not affect the survivability of nematodes, whereas neem had considerable impact on the survivability of worker termites and this may be due to the presence of active neem compounds (Azadirachtin, salanin etc.). Mortality was 40% on 4th day at lower concentration of 1.0% NSKE treatment; whereas mortality has been increased to 70% at higher concentration (4.0%) on 4 th day. There was 100% mortality after the combined treatment with 4.0% NSKE + 600 infective juvenile Steinernema glaseri, even at the first day of the experiment. In the present experiment, neem extract does not affected the survival of the nematodes. Hence, nematode and neem extract can be used for soil-insect control particularly for the subterranean termites.

Mosquitoes serve as reservoirs for viruses and other microorganisms, posing a significant health‐related issue for both humans as well as livestock. Control of these deadly disease‐producing mosquito vectors is of paramount importance. The chemical analysis of Parmotrema reticulatum was examined by GC–MS. Further, lichen‐mediated AgNPs were confirmed through UV–vis spectrophotometry, FTIR, TEM‐EDX, and XRD. After 24 h post‐treatment, the lichen‐synthesized AgNPs showed considerable toxicity against distinct Aedes aegypti instars with LC50 values of 44.61 (I instar), 51.27 (II instars), 61.34 (III instars), 72.95 (IV instar), and 89.84 (pupae) μg/mL, respectively. Further, both P. reticulatum extract and AgNPs greatly reduced the survival and reproductive efficiency of A. aegypti adults. Eventually, in conventional laboratory circumstances, the predatory effectiveness of Gambusia affinis against Ae. aegypti II and III instar larvae were 71.35% and 53.40%, respectively. In antibacterial assays, low concentrations of the P. reticulatum synthesized AgNPs inhibited the development of Pseudomonas aeruginosa and Citrobacter freundii. Surface damage, ROS production, and protein leakage are the antibacterial mechanisms of AgNPs. Overall, the lichen‐derived AgNPs can be regarded as newer and safer Ae. aegypti control instruments.