Integrated Management of Fusarium Wilt in Onion through Phytosanitary Treatments and Fertilization Modes in Burkina Faso

Onion is the dominant vegetable crop cultivated in Burkina Faso and plays a key role in food security and rural incomes. However, its productivity is limited by fungal diseases, such as Fusarium wilt. This study aims to assess the effect of pesticide use and fertilization mode on the Fusarium wilt incidence and onion productivity during the wet season. To this end, phytosanitary treatments (Idefix, Mancozeb, and SuperFaso N), and fertilization modes (NPK, Compost, and Bactericidal compost) were tested. The incidence and severity of Fusarium wilt symptoms were collected. We also evaluated the height, neck diameter, and yield. The results showed that the incidence and severity of Fusarium wilt varied significantly depending on the phytosanitary treatments and fertilization mode. At 45 days after planting, the incidence differed significantly among treatments (P < 0.001), fertilization mode (P < 0.001), and their interaction (P < 0.001). However, at 60 Days After Transplanting (DAT), only fertilization mode had a significant effect (P < 0.001). Plant height varied significantly depending on the treatments and fertilization at 30, 45 and 60 DAT (P < 0.001). Neck diameter and yield were strongly influenced by treatments and fertilization (P < 0.001), and their interaction affected yield (P = 0.033). PCA showed that yield correlated positively with neck and negatively with incidence and severity, confirming the effectiveness of neem biopesticide and compost + NPK fertilization in limiting Fusarium wilt and optimizing production. The results obtained should contribute to validating an integrated approach to managing onion plant pathogens and increasing their productivity.