Cowpea (Vigna unguiculata(L.) Walp.) is an important grain legume cultivated in most tropical and some temperate regions. It is one of the most widely adapted, versatile grain legumes of high nutritious value. Cowpea production across Africa accounts for approx.91 % of world output. Cowpea has an impact on nutrition as valuable protein source and livelihoods of small scale farmers and plays a key role in the life of many people, especially in developing countries. The International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria, holds the largest cowpea germplasm collection worldwide. Many literature sources cite that biodiversity is constantly diminishing and exposed to different hazards accelerating the speed of biodiversity loss. To avoid future losses of cowpea genetic diversity it is important to assess the cowpea accession collection at IITA to get an overview about the current conservation status and to guide future sampling. For the present study a gap analysis is an evaluation technique to estimate the degree of coverage of already sampled regions, to identify regions that need additional sampling and those where no collections have been performed yet. First the country coverage of georeferenced cowpea accession was estimated. Then Eco geographical site descriptors (temperature, precipitation, length of growing period, altitude) were extracted to deter-mine areas with environmental conditions favoured by cowpea. Afterwards regions with similar environmental conditions were identified by using GIS techniques to predict areas where the possibility of filling gaps in the collection is most likely. Furthermore, this study used the spatial analysis tools FloraMapTM, HomologueTM,ArcGISTMand DIVA-GIS to identify potential areas for future conservation activities of cowpea. The geographical scope of the present study was focused on sub-Saharan Africa. Results indicated that cowpea can be found approx. between 15◦N and 20◦S. With respect to new collections main focus should be put on countries where so fare no collections have been done, but where the spatial analysis showed high probability of encountering cowpea —Burundi, Eritrea, Equatorial-Guinea, Guinea-Bissau, Namibia and Rwanda respectively. In countries with few georeferenced accessions, existing no georeferenced passport data need to be complemented or new sampling should be carried out.

"The original research contained in this volume identifies the options for the provision of modern and improved energy services, based on renewables, to low-income rural areas, with special emphasis on the productive uses of energy. In the five countries represented - Botswana, Eritrea, Ethiopia, Zambia and Zimbabwe - the book focuses on three themes: whether a decentralized approach to energy delivery is better than more centralized provision, on the role of income-generating activities in attracting modern energy services in rural areas, and on the barriers as well as opportunities that exist in the promotion of renewable energy technologies in the rural areas of sub-Saharan Africa."--Jacket.

The advantages of shoot tip planting material in banana production are briefly outlined. The production scheme and ongoing research at IRFA/Vitropic are summarised

Describes the phytosanitary measures in force and those that are planned. These include provision of virus-free registered mother trees to nurseries, registration of citrus nurseries, regulation of seed and imports, and inspection of farms and nurseries

Outlines the history and objectives of the California Citrus Clonal Protection Program (CCPP) which conducts research and is a primary source of disease-free budwood of desirable true-to-type citrus scion and rootstock varieties designed to exclude graft transmissible diseases (virus and virus-like)

Research is directed towards study of host-parasite relations. The 3 Sigatoka leaf spot pathogens, Mycosphaerella musicola (Yellow Sigatoka), M. fijiensis (Black Leaf Streak) and M. fijiensis difformis are compared morphologically and pathogenically. Species identification by electrophoresis on acrylamide gels has been studied, the species also differ in host range, geographical range, symptoms and distribution of lesions. Early tests of susceptibility of plantlets from meristem culture suggest that they react to infection in the same way as observed in the field