Laboratory Tests of Some Mosquito Larvicidal Agents against Rice Field Mosquitoes in Malaysia
Three larvicides, Abate®, 96.2%, Bacillus thuringiensis var. israelensis (serotype 14) VectoBac® (technical powder) and Bacillus sphericus Neide (serotype H5a5b) Vectolex-WDG®, were evaluated against field collected mosquito species, Culex bitaeniorhynchus, Cx. tritaeniorhynchus, Cx. gelidus, Cx. vishnui and An. sinensis in the laboratory. The levels of susceptibility of these species to the test larvicides were different; The LC90 values ranged from 1.27 ppt to 0.24 ppm for Abate® against An. sinensis, Cx. tritaeniorhynchus, Cx. gelidus, Cx. Bitaeniorhynchus and Cx. vishnui. The LC90 values ranged from 0.50 ppb to 0.34 ppm for Culexgelidus, Cx. tritaeniorhynchus, Cx. bitaeniorhynchus, Cx. Vishnui and An. sinensis for VectoBac®. While the LC90 values ranged from 35.69 ppb to 355.94 ppm for Cx. tritaeniorhynchus, Cx. gelidus, Cx. vishnui, Cx. Bitaeniorhynchus and An. sinensis and from 0.01 ppm to 7.51 ppm, Culex tritaeniorhynchus, Cx. gelidus, Cx. vishnui, Cx. Bitaeniorhynchus and An. sinensis to Vectolex®, 24h and 48h exposure, respectively. Keywords - Mosquito, Rice Fields, Larvicidal Agents, Bioassays.