Genetic improvement has been given high priority in rice research for development in sub-Saharan Africa (SSA). This paper provides an overview of historical efforts of genetic improvement in SSA focused on improving rice productivity. It further describes yield gain of new rice varieties evaluated in recent field experiments in four selected breeding target domains, and summarizes adoption studies on rice varieties. Efforts to develop rice varieties adapted to diverse rice production systems in SSA have been made by several research organizations, including national agricultural research institutes, bilateral organizations, and three CGIAR centers. The efforts have resulted in the release of around 570 rice varieties in 10 major rice-producing SSA countries by 2020. Among these varieties, the most well-known are interspecfic upland rice varieties “New Rice for Africa (NERICA)” that were developed from crosses between improved Oryza sativa tropical japonica and Oryza glaberrima varieties. However, recent field assessements demonstrated that upland rice yield can be further improved through introduction of upland indica materials from Asia. In contrast, lowland interspecific rice varieties out-yielded the previously released improved O. sativa varieties in selected SSA countries. Field assessments in Senegal and Madagascar did not demonstrate the yield advantage of the recently-developed varieties including hybrids over best performing ones released before. The adoption level of improved varieties in terms of share of area occupied by improved varieties in 18 SSA countries was 40 % in 2008 with old varieties that were released before 2000 being dominant and 7% of the total rice area occupied by NERICA varieties. Especially in irrigated and rainfed lowland rice systems, the majority of dominant varieties were still those introduced from Asia. Panel data between 2002 and 2019 from the Senegal River Valley also confirmed this, and Sahel 108, which was introduced from Asia and released in Senegal in 1994, accounted for >70 % of the total rice area in both the wet and dry seasons in 2019. The implications of this review for future rice genetic improvement and varietal replacement in SSA are discussed.

在水稻研究中，将遗传改良作为撒哈拉以南非洲发展的高度优先事项。本文概述了SSA致力于改良稻米生产力的遗传改良的历史努力。它进一步描述了最近在四个选定育种目标领域进行的田间试验评估的新水稻品种的增产，并总结了对水稻品种的采用研究。包括国家农业研究机构，双边组织和三个国际农业研究磋商小组在内的若干研究组织已努力开发适应南南非洲不同水稻生产系统的水稻品种。通过这些努力，到2020年，在10个主要的水稻生产SSA国家中释放了大约570个水稻品种。在这些品种中，水稻为热带粳稻和水稻为甘蓝变种。然而，最近的场assessements表明，旱稻产量可以通过导入的高地得到进一步改善籼稻从亚材料。相反，低地种间水稻品种的产量高于先前释放的改良稻SSA特定国家/地区的品种。在塞内加尔和马达加斯加的田间评估没有显示出最近开发的品种（包括杂种）比以前发布的表现最好的品种在产量上的优势。2008年，在18个撒哈拉以南非洲国家，改良品种的采用水平按改良品种所占面积的比例为40％，其中2000年之前发布的旧品种占主导地位，占NERICA品种水稻总面积的7％。特别是在灌溉和雨养低地水稻系统中，大多数优势品种仍然是亚洲引进的。塞内加尔河谷2002年至2019年之间的面板数据也证实了这一点，从亚洲引进并于1994年在塞内加尔发布的Sahel 108在2019年的湿季和旱季都占稻米总面积的70％以上。