Current Knowledge on Biotic Stresses affecting Legumes: Perspectives in Cowpea and Soybean

Abstract

Legumes are economically important crops for the achievement of food security status in many countries in the tropical and subtropical regions of the world. Among various environmental stresses, biotic constraints to the production of grain legumes such as cowpea and soybean are becoming increasingly significant with the recurring change in climatic patterns and diverse environmental alterations. The economic impact of biotic factors such as disease-causing pathogens (fungi, bacteria, viruses and nematodes), insect pests and parasitic weeds has become overwhelming. These biotic stressors induce a wide range of damage symptoms which include stunting, wilting of stems, defoliation, root rots and premature death of plants. Yield losses due to the activities of biotic stress factors have been very significant. Hence, it is imperative to be informed of the various biotic stressors that affect the growth and yield potential of cowpeas and soybeans in various cropping systems. This review seeks to highlight existing pests and diseases in cowpea and soybean and evaluate their impact on the growth and productivity of these crops. It is hoped that the review will further spur scientific research into how these biotic factors can be managed or even manipulated to ensure agricultural sustainability, high economic returns, and global food security.