Analysis of distribution and pathogenesis of Mycosphaerella fijiensis, in subsistence farming systems of banana and plantain in Benin

Black Sigatoka, caused by Mycosphaerella fijiensis is responsible of phytosanitary constraints that affect considerably the global banana and plantain production. The distribution and severity of this disease in banana and plantain cropping systems result from both intrinsic and extrinsic factors that interplay dynamically. In this paper, we provide field incidence and severity of the disease in banana and plantain subsistence farming systems in 17 districts in Benin Republic. Pathogenicity test was conducted in greenhouse followed by the mapping of the study areas based on the virulence of M. fijiensis isolated from plant and soil samples collected from 114 plantain and banana fields. The results showed that the incidence of the disease in banana subsistence farming systems varied significantly according to the production area (p = 0.0465), the banana and plantain cultivars (p = 0.0184) and the types of cropping system (p < 0.0001). Dessert-banana-based monoculture systems were the most sensitive to pathogen attacks, with a Disease Severity Index (DSI) of 38.26 ± 0.53, followed by the intercropping systems (DSI = 33.64 ± 0.74) and home garden systems (DSI = 34.63 ± 0.61). Overall, plantain cultivars across different systems were more resistant M. fijiensis attacks (DSI = 35.57 ± 0.49), compared dessert banana subgroup (DSI = 37.46 ± 0.90) recorded to be the most susceptibleThe longest incubation times of 15.66 and 16.56 days recorded from isolates collected respectively in Houeyogbe in Zagnanado indicated the presence of the least virulent isolates. Contrariwise, the most virulent isolates with the shortest incubation times ranging from 11.75 to 12.58 days was recorded in Djidja and Toffo. These findings provide novel and valuable insights into epidemiology of banana and plantain farming systems in Benin. This outcome is essential to offering appropriate advice and support to farmers. In addition to this, existing production models are to be improved so that they can more effectively and sustainably control and prevent black Sigatoka disease.