Susceptibility of five strains of vine mealybugs, Planococcus ficus (Signoret), to chlorpyrifos

[摘要] ENGLISH ABSTRACT:Colonies of Planococcus ficus (Signoret) were reared from three different areas, Hex RiverValley, Robertson and Stellenbosch. An insectary colony and a table grape colony fromNietvoorbij experimental farm were also included in the study. A range of concentrations ofchlorpyrifos was applied topically to individuals from the different colonies. The Stellenboschpopulation had the lowest LDso, although it was not significantly different from that of theinsectary and Robertson colonies. The Hex River Valley and table grape colonies had asignificantly higher LDso than the Robertson, Stellenbosch and insectary colonies, although therelative tolerance was 1.5, which would probably not result in significant control failure in thefield. However, this does indicate that there is potential for the development of resistance tochlorpyrifos in the vine mealybug in South Africa.

[发布机构] Stellenbosch University