Laboratory evaluation of predation of Toxorhynchites amboinensis (Diptera:Culicidae) on three mosquito vectors of arboviruses in the Philippines

Publication date: October 2019Source: Biological Control, Volume 137Author(s): Jonathan R. Digma, Augusto C. Sumalde, Cristina C. SalibayAbstractThe spread of arboviral disease in the Province of Cavite, Philippines has resulted to the declaration of state of calamities which has led to higher disease burden and economic costs for the province and its population. With this situation, the use of biological control agents like the naturally occurring non - hematophagous Toxorhynchites species with predatory capacity at its larval stage was explored as an alternative approach to environmentally degrading chemical insecticides. Laboratory assessment of the predatory efficacy of wild type Toxorhynchites amboinensis was done independently against Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus prey larvae. Field collected Tx. amboinensis from selected areas of Cavite were reared until adult stage and allowed to oviposit in their rearing cages as a source of test insect. Using similar larval instar for the predator and prey species, predatory larvae were individually exposed to 20 and 40 prey densities in plastic cups. Predatory efficacy test was significantly different between the two prey densities offered. Higher predation rate ranging from 19.5 to 20.4 (48.75–51.00%) was recorded in the predatory larvae exposed to higher prey densities. Analysis of the predatory impact (PI) also revealed significant differences among the larval instars. The 4th instar larva was fou...
Source: Biological Control - Category: Biology Source Type: research