杂交晚稻穗粒结构观察分析

对多个两系和三系杂交晚稻新组合的穗总粒、一次枝梗、二次枝梗、结实率和空秕率等穗粒性状进行了观察分析，指出了穗粒主要性状差异主要来源于组合本身，一次枝梗性状较稳定，二次枝梗受营养和环境条件影响较明显。从而为新组合的选育及高产栽培提供了依据。

Analysis on Panicle and Spikelet Structure of Late Hybrid Rice

Seven late hybrid rice combinations (3 two-line hybrids and 4 three-line hybrids) were surveyed on their panicle and spikelet characters such as total spikelets per panicle, number of primary branches, number of secondary branches and seed setting percentage. The results showed that all of the characters varied with different hybrids; the number of primary branches and the number of spikelets on the primary branches were more stable than that of and on secondary branches and seed setting percentage of primary branches was higher than that of secondary branches in all the hybrids; compared with the three-line hybrids, the two-line hybrids had more secondary branches and the spikelets on them and less degenerated secondary branches. It is concluded that the total number of spikelets is mainly from secondary branches in two-line hybrids while the total number of spikelets is largely from primary branches. Therefore, in cultural management, suitable practices should be applied according to the panicle and spikelet characteristics of different combinations.