In Vitro Production of Male Sterile Rice Plants

Abstract

Huge economic and social benefits from the application of hybrid rice production have been obtained in China since 1976. The total area of hybrid rice plantation has now reached 16 million ha/year and constitutes 50% of the total rice area in China. Compared with conventional varieties, the yield of hybrid rice has increased by an average of around 1500 kg/ha (Fu and Gong 1994). Outside China (United States, Philippines, Thailand, Japan, Indonesia, Korea, etc.), hybrid rice production has also been successful on a small scale (Yuan and Mao 1991). However, the female parents of most combinations used in hybrid rice production in China were almost all derived from the same cytoplasm, Wild Rice Abortive cytoplast (WA-type cytoplasm). The long time span (almost 20 years), the large growing area (16 million ha/year), and the use of a single source of the cytoplasm of male sterile (ms) may cause the hybrid rice to be vulnerable to diseases or insect epidemics. Moreover, a single source of cytoplasm for the male sterile lines limits the choice of hybrid combination. Researchers in hybrid rice breeding have therefore been seeting a new source of cytoplasm (non-WA type cytoplasm) for a long time.