Differential efficacy evaluation of formulations of Bacillus thuringiensis Var israelensis against mosquitoes: a laboratory investigation.

ABSTRACT

The efficacy evaluation of three formulations; wettable powder (W.P.) floating pellet and beads of Bacillus thuringiensis Var israelensis (Bti), revealed a greater susceptibility of the early larval instars of mosquitoes to Bti, sensitivity of anophelines to floating pellet, culicines to bead and equal efficacy and faster kill of W.P. to all the mosquitoes tested. A greater persistence of the slow release formulations, floating pellet and beads for 49 and 28 days against anophelines and culicines respectively was observed in contrast to a maximum persistence for 21 days in case of W.P. formulation.