Charcoal rot in common bean with special reference to Kenya

Abstract

Charcoal rot caused by Macrophomina phaseolina (Deuteromycetes: Coelomycetes) is found throughout the tropics and subtropics and has a wide host range. Together with most of the legume crops, the common bean (Phaseolus vulgaris) Is a good host for the fungus which causes a range of symptoms, depending on environmental conditions and age of the plant. In addition to charcoal rot, which is a stem or stalk rot disease, the pathogen also causes damping‐off and seedling blight in beans. Charcoal rot in the mature plant is associated with senescence which is accelerated by water stress. The disease is most damaging in areas of unreliable rainfall and high temperature. In Kenya, beans are usually grown in mixed stands with maize, sorghum or millet. Population pressure has led to the cultivation of beans on land prone to drought. M. phaseolina is one of the most important pathogens affecting all the main crops of the farming systems in the semi‐arid areas of eastern Kenya and resistance to charcoal rot is a priority if beans are to be increasingly grown in these areas. The paper reviews the literature on charcoal rot of beans and on other crops where similar work has not been reported specifically for beans.

Keywords:

• Macrophomina phaseolina
• charcoal rot
• beans
• Kenya