中文摘要：

以61个杂交晚稻组合组成供试群体，综合运用多种统计方法对单位面积产量与产量相关性状的相互关系进行了剖析，以期为我国长江中游南部稻区尤其是江西生态条件下杂交晚稻的高产育种提供科学依据。结果表明，在产量已达到较高水平的情况下，杂交晚稻高产育种的方向必需着重选配大穗、大粒型的组合，但除此之外，还必需在保证较高有效穗数的基础上寻求有效穗数与大穗、大粒的协调结合。通过成穗率高的选择，不仅对提高新组合的产量水平具有正效应，而且成穗率可以作为一个核心性状协调多穗与大穗、大粒之间的矛盾，进而实现有效穗数多与大穗、大粒在更高水平上的结合，从而获得更高的产量。在实现有效穗数多与大穗、大粒在更高水平上的协调结合的基础上，提高结实率也是必需顾及的一个方向；其中的关键是打破结实率与每穗总粒数之间的不利相关。

英文摘要：

The trial population is composed of 61 hybrid late season rice combinations. The relationship of the grain yield per unit of area and yield correlated characters was analyzed by synthetically utilizing many kinds of statistical methods. It is attempted to provide scientific basis for high yield breeding of hybrid late season rice in the south rice area of middle reaches of Yangtze, particularly in Jiangxi ecological condition. The results in- dicated that,in the situation that the grain yield had achieved a higher level, the direction of high yield breeding in the hybrid late season rice was to emphatically select and match combination with more spikelets per panicle and big grain. In addition, it must seek unisonous combination of effective panicle number and more spikelets per panicle and big grain on the basis of higher effective panicle number. The new combination of hybrid late season rice was selected through high productive tiller percentage, which had positive effect to improve the yield level of new combination. Moreover, productive tiller percentage can be used as a core character to coordinate the contradiction of many effective panicles with more spikelets per panicle and big grain, then the combination of effective panicles and more spikelets per panicle and big grain in higher level is realized, thus a higher grain yield is obtained. On the base of realizing the unisonous combination of more effective panicles and more spikelets per panicle and big grain in a higher level, the improvement of filled grains percentage is also essential taken into consideration. The key point is to break the disadvantageous correlation of filled grains percentage and spikelets per panicle.