Towards a rational use of African rice (Oryza glaberrima Steud.) for breeding in SubSaharan Africa

Abstract

Africa Rice Center (AfricaRice) plays an important role in germplasm enhancement for their adaptation to different ecologies of upland, lowland, irrigated, mangrove and deep water. The genebank of AfricaRice contains over 20,000 rice accessions, notably two cultivated species (Oryza sativa and O. glaberrima) and wild species (O. longistaminata, O. barthii and O. stapfii), which are being used in breeding programs. In recent years, NERICA rice suitable for upland, lowland and irrigated ecologies were developed from interspecific crosses between O. sativa and O. glaberrima. For the better utilization of O. glaberrima, characterization studies of genetic diversity have been made using both molecular and conventional tools. The screening of this material for biotic and abiotic stresses has allowed us to identify firstly, genes for resistance to major rice diseases such as rice yellow mottle virus, rice blast disease and insect pests, and secondly, new sources of tolerance to drought, salinity and iron toxicity. A thorough exploitation of these resistance/tolerance genes will lead to rice varieties of better performance, under the heterogeneous production conditions in Africa. AfricaRice therefore planned to better exploit O. glaberrima and wild species conserved in its genebank through the use of biotechnology tools. Emphasis shall also be on the improvement of grain quality, nutritional values and post harvest techniques; this will greatly enhance the achievement of the objective of producing better quality rice in Africa. The objective of this paper is to propose several ways to better exploit O. glaberrima as breeding materials than the current interspecific breeding program through the critical review of published data and new additional data on the performance of NERICA lines.