Optimization of Late Blight and Bacterial Wilt Management in Potato Production Systems in the Highland Tropics of Africa

Abstract

Late blight and bacterial wilt are two formidable disease constraints on potato and account for significant losses in Sub-Saharan Africa (SSA). In this chapter, various management techniques for late blight and bacterial wilt diseases are highlighted with examples drawn from diverse research. The modified disease management approaches include resistant cultivars, reduced fungicide applications, disease monitoring based on field scouting, cultural practices, post-harvest management and farmer training. Deployment of cultivars with resistance genes and quantitative resistance in addition to fungicide use has contributed significantly to sustained late blight management in tropical Africa. Similarly, cultural practices such as date of planting, disease-free tubers, roguing and bio-rational approaches (plant-derived extracts and phosphoric acid) have been used to a lesser degree. Disease monitoring and weather-based predictions in relation to fungicide applications have been utilized in conjunction with host-plant resistance. Similarly, bacterial wilt has been successfully managed through non-chemical means which include crop rotation, sanitation (removal of wilted plants, destruction of crop residues), and minimum post-emergence cultivation of potatoes. Small-scale seed plot technique, non-diseased tubers, soil amendments and less susceptible cultivars have been important components for integrated management of bacterial wilt disease. The holistic approach for control of late blight and bacterial wilt ultimately lead to increased potato production and better economic returns in the diverse potato production region of SSA.