BIOLOGICAL CONTROL OF MOSQUITO LARVAE WITH MESOCYCLOPS LEUKARTI1)

Abstract  The control efficacy of a predatory copepod, Mesocyclops leukarti , collected in Jining, and its compatibility with Bacillus sphaericus (B.s. ) and B. thuringiensis var. csraefensis H-14 ( B. t. i. ) against mosquito larvae were evaluated in the laboratory and in the field. In the laboratory, M. leukarti showed higher predatory activity toward first instar larvae of Aedes albopictus than toward that of Anopheles sinensis and Culex pipiens pallens. Cage simulation test showed that larvae of Cx. pipiens pallens, An. sinensis and Ae. albopictus could be eliminated within 9, 10 and 7 weeks after interaction with the copepods respectively. M. leukarti population can grow quickly, and its mass production is easy and economic. However, pilot field trials indicated that M. leukarti alone could not eradicate mosquito larvae of the three species rapidly and completely as by chemical insecticides, although they could persist in mosquito breeding habitats longer than the mosquito season. When Mesocyclops was used in combination with B. s. and B. t. i. , higher and sustainable control effects were achieved. So this combination, which achieved the rapid larvicidal and sustainable control effect, was presumed to be practical and could be integrated into mosquito control program.