Prevalence of Cowpea Charcoal Rot and Molecular Identification of Three Macrophomina Species in the Sudanian and Sudano-Sahelian Zones of Burkina Faso

Abstract

Cowpea (Vigna unguiculata (L.) Walp.), the main legume crop cultivated in Burkina Faso, is attacked by several pathogens, including fungi. Among these fungi, Macrophomina phaseolina (Tassi) Goidanich is responsible for charcoal rot and leads to significant production losses ranging from 80 to 100%. These losses could be significantly reduced through the use of disease-resistant varieties. The objective of the study was to contribute to the strengthening of knowledge of the causal agent of cowpea charcoal rot for better management of the disease in Burkina Faso. For this purpose, a seed health analysis, using the blotter paper method. A sanitary analysis was carried out on 27 seed samples collected from 14 localities distributed in the two main climatic zones of cowpea production. Most of the seed samples collected (96.30%) were infected with M. phaseolina. The fungus was found in seeds at average infection rates of 35.25% in the Sudanian zone and 27.86% in the Sudano-Sahelian zone. A preliminary molecular characterization of 51 isolates of Macrophomina lead to identify M. phaseolina as the main species present in cowpea seeds in the two targeted areas.