Larvae of the elephant mosquitoes, Toxorhynchites spp. (Diptera: Culicidae) are predacious on larvae of other mosquito species and some small aquatic organisms; this predatory behavior can be applied in (mosquito) vector control. The present study examined the feeding behavior of Toxorhynchites splendens on Aedes albopictus in relation to search area [volume of water (X1)] and prey density (X2), prey instars, predatory preference and larvae's functional response on variable prey densities. Experiments were conducted to determine changes in the feeding activity of T. splendens with different search areas and showed that rate of prey consumption was inversely proportional to the search area as evidenced by a negative value of X1 in the regression equation and positively related to prey density. The non-linear polynomial logistic regression estimated a significant linear parameter (P1 < 0) for the functional response analysis suggesting a Type II functional response. Differences in feeding response related to the different combinations of prey instars were statistically not significant (p > 0.05), expressing that all the instars of prey were equally susceptible to the predator. Toxorhynchites splendens preferred to consume Ae. albopictus larvae rather than Tubifex when supplied together as a food source.

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The best method for preventing mosquito-borne diseases is to reduce the mosquito population. The goal of the current study was to assess larvicidal efficacy of fruit extract of Diospyros kaki against Aedes albopictus larvae and to the non-target organisms. Bioassays were performed with crude and acetone solvent extracts on Ae. Albopictus larvae. Additionally, studies on the composition of phytochemicals were conducted. Through the use of Log-probit, regression, and ANOVA analyses, statistical explanations were derived. Both the crude and the acetone extract significantly reduced mosquito larvae. At 350 ppm concentration, 100% death of the 1 st and 2 nd instar larvae was observed after 72 hours. Tannins, steroids, alkaloid, and flavonoids were present in fruits as secondary metabolites. Both the extract had no effect on a non-target organism. The fruits of Diospyros kaki have the capacity to targetspecifically regulate Ae. Albopictus larvae.