Effect of Kaolin Particle Film Formulation Against Populations of the Aphid Lipaphis erysimi Kalt. (Homoptera: Aphididae) in Cabbage

Abstract

Infestations of the aphid Lipaphis erysimi Kalt.cause a mean yield loss of cabbage that varies from 35.4% to 73.3% depending from agro-climatic conditions. To control this pest insect in Sub-saharan Africa, synthetic chemical insecticides are usually applied. Kaolin is a white, non-abrasive, inert aluminosilicate mineral that has been shown to effectively protect host plants from insect pests including lepidopterans, sucking insects and mites. The present work is aimed to study the effects of kaolin on the population dynamics of L. erysimi for the Integrated Management of this insect pest in cabbage. To carry out the present study, kaolin powder was dissolved in water to obtain a concentration of 5% kaolin. The plants were sprayed with kaolin suspension every week and every 4-days in 2 respective experiments. Results showed that kaolin sprays significantly reduced aphid populations density. Nevertheless, more frequent applications (every 4 days) did not improve kaolin efficacy. It is concluded that kaolin technology should be combined with another plant protection measure in order to keep aphids population under control in cabbage.