Sorghum Midge [Stenodiplosis sorghicola (Coquillet, 1898)] Dynamics and Abundance Study in the Southern Sudanian and Sudano-sahelian Zones of Burkina Faso

Abstract

Sorghum is one of the most widely grown and consumed cereals in Sahelian countries, particularly in Burkina Faso. However, its cultivation faces numerous constraints, both biotic and abiotic. Among the biotic constraints, insect pests, notably the sorghum midge, Stenodiplosis sorghicola (Coquillet, 1898), constitute one of the major obstacles to sorghum production in the Sahelian zone. This insect is responsible for yield losses ranging from 33% to 100%. The aim of this study was to analyze the population dynamics of this insect and to assess the level of infestation in sorghum fields. Data on midge populations were collected using yellow insect traps set in sorghum plots in the South Sudanian and Sudano-Sahelian agroecological zones of Burkina Faso. These data were collected during the 2023/2024 and 2024/2025 cropping seasons. Assessments of insect damage and field spikelet sampling were carried out in 48 villages in these two sorghums growing zones during 2024/2025 cropping season. The results showed that the sudano-sahelian zone had the highest rate of midge infestation, with two generations of populations observed in 2023 and three generations in 2024. In Southern Sudan agro-ecological zone, only one generation of midge populations was observed in 2023 while three generations were observed in 2024. In terms of damage caused by the insect, the results also showed that the highest damage rates were recorded in the northern sudan zone, with 42% damage compared with 17% in the southern sudan zone. Overall, midge population was low in southern-sudan areas than in northern-sudan site and result of midge damage is correlated with population abundance. These results could provide an essential basis for guiding agricultural policy decisions, particularly for the sustainable management of this pest.