【Abstract】 Castor is a monoecism, with pollination and indefinite inflorescence, on which the red female flowers are at the upper part and the yellow male flowers down, the male sterile plants could be found by chance in breeding. In 1996, five male sterile plants were obtained, of which the female were fertile after crossing between sister lines, and the spikes of single plant were so big and plentiful that the productivity was increased by 30%~50% than that of common plants, and the male sterility can be kept to the next year after pruning the plants. Five male sterile lines were got through asexual reproduction in the next 2 years, and about 2% of plants appear a few male flower in the process of asexual reproduction, which could maintain the female rate over 95% as a maintainer line.更多还原