Sampling lepidopterous pests on maize in West Africa

Abstract

AbstractThe spatial distribution of five lepidopterous pests, Sesamia calamistis Hampson (Noctuidae), Eldana saccharina Walker (Pyralidae), Spodoptera exempta (Walker) (Noctuidae), Mussidia nigrivenella (Ragonot) (Pyralidae), and Cryptophlebia leucotreta (Meyrick) (Tortricidae), on maize in West Africa is described using Taylor's power law and the relationship of proportion of infested plants to the mean density. All five species showed a highly aggregated distribution, with Taylor's indices of aggregation ranging between 1.23 for C. leucotreta and 1.52 for Sesamia calamistis. Enumerative and binomial sampling plans that incorporate Taylor's power law are proposed to estimate mean densities of S. calamistis, C. leucotreta and the species complex consisting of E. saccharina, M. nigrivenella and Spodoptera exempta which showed similar spatial distributions, with a predefined reliability level.