Field effects of kaolin particle film formulation against major cotton lepidopteran pests in North Benin, West Africa

Abstract

The present study assessed the field efficacy of applying a formulation of kaolin particle on cotton plants against major lepidopteran pests in Benin using a complete randomized block design. Plants were sprayed weekly using Berthoud Ultra Low Volume sprayer at a rate of 30 l per hectare. The effects of kaolin application on the oviposition of the cotton bollworm Helicoverpa armigera as well as on the population dynamics of larvae of the major lepidopteran pests species were assessed. During the first 2 weeks of the observations, H. armigera oviposited about four times fewer eggs on kaolin treated plants, but this effect was reduced with time. Kaolin treatment maintained the number of H. armigera larva below established economic thresholds for about 4 weeks after the first application. The number of larva of the other species such as Spodoptera littoralis, Sylepta derogata and Earias spp. was also significantly reduced on kaolin treated plants. The benefits and conditions under which the application of kaolin may contribute to Integrated Pest Management programmes are discussed.