Protecting the African banana (Musa spp.): Prospects and challenges
In Africa, bananas (Musa spp.) are staple food crops and sources of income that are cultivated as backyard plantings, mixed-crop plantings and in commercial plantations. Continued production of bananas and plantains, however, is threatened by several important pests and diseases. Nematodes, particularly, are responsible for significant losses across Africa, and the banana weevil (Cosmopolites sordidus) damages both cooking (AAA-EA genome) and dessert bananas (AAA genome). Since its introduction onto the continent, black leaf streak has spread to all African tropical banana production areas, causing immense damage to plantations. Fusarium wilt is important in dessert banana plantings, while Xanthomonas wilt has devastated bananas in Central and Eastern Africa since 2001. Both Banana bunchy top virus and Banana streak viruses occur on the continent. Because of the limited resources available to backyard and mixed-crop growers, many pests and diseases are only partially controlled or not controlled at all, making banana production in Africa highly vulnerable. More importantly, many pests and diseases are indiscreetly disseminated because of limited resources and knowledge. For these reasons, large growing areas have been forced out of further production. Without substantial financial resources, the effect of pests and diseases in Africa can be significantly reduced by promoting the use of clean and healthy planting material, sanitation practices, and quarantine regulations to prevent dissemination of existing pathogens and pests, and the introduction of important foreign pathogens such as Fusarium oxysporum f. sp. cubense 'tropical race 4', and those causing Moko bacterial wilt and Blood bacterial wilt. Two banana breeding programs and several facilities for plant biotechnology already exist in Africa and should be used to develop banana cultivars resistant to pathogens and pests. More importantly, national and regional resources should be pooled in order to ensure sustainable banana production in Africa.