In Burkina Faso, corn is one of the main cereal crops of great nutritional and economic importance. However, its production is strongly hampered by competition from weeds. This study was carried out with the aim of identifying the main harmful weeds of corn in the south-west zone of the Burkina Faso. Floristic surveys were carried out during two successive agricultural campaigns, in 2020 and 2021, in peasant fields using the field tour method. The results showed that the corn weed flora is made up of 81 species distributed in 61 genera and 20 families. The most dominant families in terms of number of weed species are, in escending order, Poaceae (34.62%) and Asteraceae (8.97%). According to the harmfulness indices, Ipomoea eriocarpa (Fc=97.4%), Triumfetta cordifolia (Fc=90.7%), Striga hermonthica (Fc=72.1%), Senna occidentalis (Fc=55.9%), Pupalia lappacea (Fc=54.3%), Crotalaria barkae (Fc=50.9%) and Vernonia galamensis (Fc=50.3%) are considered to be more harmful, with high centesimal frequencies (Fc ≥ 50%). This flora is dominated by Therophytes (68%), with 56 species revealed, followed by Chamephytes (16%), with 13 species. The similarity coefficient value (Cs=89.24%) reveals a floristic homogeneity between the three provinces involved in the study. These results could serve as a preliminary basis in the development of a biological control method against harmful weeds in corn crops.

Weed, Cereals, Semi-arid zone, Floristic inventory, Burkina Faso