Overall Dominance of Spodoptera Frugiperda Smith (lepidoptera: Noctuidae) Within the Lepidopteran Pests Community Infesting Maize Fields in the Littoral Region of Cameroon

Maize is one of the most important staple food crops in Africa, however its production is hampered by many constraints including attacks of lepidopteran pests (LP). Species composition and importance of LP that damage maize has been deeply documented in Africa. However data are scarce and outdated for the Littoral Region of Cameroon. Selected farmer fields were visited and damages to maize were assessed using standard methods. Three stations chosen on the basis of elevation and three maize growth stages were considered. Lepidopteran larvae were collected from the crop and maintained in the Laboratory until adult emergence. The adult insects were later identified using available keys. The results revealed that infestation rate was high at the field level (96.02%) and moderate at the plant level (36.0 ± 48.1%) while the plant infestation severity was mild (2.25 ± 0.64). The rate and severity of plant infestation varied significantly with the elevation and maize growth stages. Eight species of LP were identified belonging to eight genera and four families. The community composition was also related to elevation and maize phenology. The fall army worm (FAW) Sp. frugiperda was the dominant species at all elevation and during the vegetative growth while Eldana saccharina (Walker) dominated during the mature stage. These results support the competition and displacement hypothesis of stemborers by the FAW, and will be useful when designing LP management options.