Importance of the wet and dry seasons in the seasonal fluctuation of Spodoptera frugiperda J.E Smith (Lepidoptera: Noctuidae) populations in a maize-growing agrosystem in western Burkina Faso.

Fluctuation saisonnière des populations de Spodoptera frugiperda.

Abstract

With a view to contributing to fall armyworm control in Burkina Faso, we conducted experiments on a number of climatic parameters likely to modify the pest's population dynamics in a maize-growing environment. The results show an earlier onset of attacks in the rainy season than in the dry season. Larval density was a function of the type of season considered (p < 0.000). It was higher in the rainy season than in the dry season. At the plant flowering stage, mean damage scores showed greater damage in the dry season (p < 0.000). In sum, the results show that agrometeorological parameters, plant growth stage and geographical location are factors likely to influence S. frugiperda population dynamics. Thus, for effective control of the pest, we recommend phytosanitary interventions as early as four weeks after maize sowing, and less widely spaced sowing dates across the zone. With this knowledge, farmers and researchers can effectively plan when control measures need to be stepped up for effective control of this insect pest.