EVALUATION OF STEM BORER SPECIES DIVERSITY AND IDENTIFICATION OF THE FALL ARMYWORM STRAIN IN CEREAL CROPS AND SUGARCANE FIELDS OF SWAZILAND

Abstract

Lepidopterous stem borers constitute one of the major constraints to cereal and sugarcane production in Swaziland and the invasive fall armyworm is also becoming a major threat to maize production in the country. Valid identification of these pests is vital for the development of effective and sustainable pest management programmes. In this study geographical populations of Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) and cereal stem borers collected during surveys conducted in the year 2017 were identified using sequences of the mitochondrial cytochrome-c oxidase I (COI) gene. Phylogenetic analyses and percentage sequence divergence of the collected specimens revealed that cereals and sugarcane in the country are attacked by four species of stem borers [(Busseola fusca Fuller (Lepidoptera:Noctuidae), Sesamia calamistis Hampson (Lepidoptera:Noctuidae) Chilo partellus Swinhoe (Lepidoptera: Crambidae) and Eldana saccharina Walker (epidoptera: Pyralidae)] and a single strain (Rice Strain) of fall armyworm. These information could be used in future studies on migration pattern, host range and natural enemy of the pests that are vital for developing sound and sustainable fall armyworm and/or stem borer management programs.