Abstract
Scaling up agroforestry is crucial to increase food production and reduce poverty in Sub-Saharan Africa. An excellent agroforestry tree Grevillea robusta, tree grown intensely in Kenya and Uganda, is threatened by a new disease. Our recent results show that it is serious, wide-spread and probably caused by Botryosphaeria sp.a pathogenic fungal genus. During the research phase of agroforestry technologies, diseases are kept under control, but when spread to a lot of farmers disease problems are becoming more evident. Scaling up of agroforestry results in more trees on the farms and an increased risk for spread of tree pests, like this disease, forcing farmers to uproot their trees and hampering the adoption of tree plantation. Therfore to make agroforestry technologies more robust disease management needs to be developed. The increased acreage and number of trees/ha leads to an enlarged number of potential hosts, and a larger population size for the pathogen to evolve genetically into more aggressive genotypes. To meet the overall objective of disease control, research will be directed to the following areas: Disease and pathogen distribution, on local and regional scales; Mode of spread and host range, including threats to other agroforestry trees. The research also intends to intensify contacts between young scientists in tree pathology in Ethiopia, Uganda and Kenya as well as with ICRAF, an important capacity building for development of sustainable research in the region.
Sweden