Chapter 23 - Management of potato pests and diseases in Africa

Abstract

Potato production in developing countries is threatened by adverse abiotic and biotic factors. In Africa, pests and diseases are major potato production limiting factors, severely affecting potato yield and tuber quality. In this part of the world, potato yield losses due to pests and diseases can be as high as 100%. In subSaharan Africa in particular, where most potato crops are produced by small-scale or subsistence farmers, not only information on accurate identification of pests and diseases is not readily available, but also management tools are lacking. This makes it difficult for growers to compartmentalize problems into pest and disease types while trying to practice integrated pest management. Therefore, unlike most of the chapters in this book, we will address both pests and diseases, including insects and nematodes. Major insect pests include potato tuber moth, aphids, and pea leafminer. Minor and sporadic pests such as loopers, cutworms, armyworms, thrips, and spider mites are also discussed. Plant parasitic nematodes, including root-knot nematodes and potato cyst nematodes, have become an emerging threat to potato production in Africa and warrant a discussion. Diseases caused by viruses, bacteria, and fungal pathogens are the most important component of a biological constraint to potato production in Africa. As a result, potato viruses, bacterial wilt, common and powdery scab, early and late blight, and Verticilium wilt are highlighted in this chapter. Furthermore, management of these potato pests and diseases is discussed, with emphasis on plant host resistance. We will review natural sources of resistance and progress in breeding for resistance against major pests and diseases commonly found in Africa. This comprehensive review will allow potato producers and researchers in Africa to find the information in one place, thereby allowing them to make timely and more effective management strategies based on informed decisions when confronted with pest and disease challenges.