三交水稻的育种研究：II．三交中晚稻杂种优势的比较研究

Four homozygous cms-lines FeiA, Zhong9A, Jin23A and Zhenshan97A, four heterozygous cms-lines FeiA/XieqingzaoB, Zhong9A/XieqingyzaoB, Jin23A/XieqingzaoB and Zhenshan97A/XieqingzaoB, and three restorer lines 752, Ce64-7 and Youmi2 were used to make 8×3=24 F1 hybrids including 12 single hybrids and 12 three-way hybrids. The results showed that the grain yield of three-way hybrid rice was increased by 6.11% as compared with the corresponding single cross hybrids on an average and 58.33% of the combinations had superiority. The grain weight per plant of Zhenshan97A/XieqingzaoB∥Ce64-7 was the highest, its superiority rate Ⅰ and Ⅱ (SR Ⅰ and SR Ⅱ) were 60.29% and 9.94% respectively. The coefficient of variability of plant height and days to heading in three-way hybrids were close to those in corresponding single hybrids. It suggested that the three-way hybrid rice in mid-late season cropping will be preference in production. The 1 000-grain weight of three-way hybrid rice showed most outstanding superiority, and the attention should be paid in three-way hybrid rice breeding.