气温对杂交水稻Ⅱ优718产量优势的影响分析

本文采用5个品种,6个播期的裂区试验设计,3次重复,研究不同播期和气温对水稻Ⅱ优718与对照Ⅱ优838不同性状及产量杂种优势的影响.结果表明:①Ⅱ优718和Ⅱ优838不同性状的杂种优势强弱均表现不同;②F1代产量高的并不一定是中亲优势强的,这主要取决于亲本的自身表现;③不同的环境对产量优势的表现都具有不同的影响,其影响的大小取决于环境因素是否有利于F1代的生长发育和双亲的遗传基础是否正常表达;④采用逐步回归分析后发现F1代及其父母本不同生育阶段的活动积温和有效积温对Ⅱ优718和Ⅱ优838的产量优势均有不同程度的影响.

Effect of Temperature on Yield Performance of Hybrid Rice II You 718

In 2006,the experiment was carried out in three replications of a split plot design to study the effect of sowing date and temperatuere on the traits and yield of hybrid rice II You 718 and the control II You 838. The main plot consisted of 6 sowing dates and the sub-plot consisted of 5 varieties. The following results showed: (i) II You 718 and II You 838 performed differently in trait heterosis; (ii) Varieties with high F_2 yield are not certainly those with high mid-parent heterosis, and the F_2 yield was decided by the per se performance of the parents; (iii) Different environmental conditions had different influence on the variety yield performance, and the high yield performance was decided by the envirionmental factors which are favourable for the F_1 plant growth and development and for the trait expression; (iv) Active accumulated temperature and effective accumulated temperature in different growth stages of F_1 plants can affect the yield heterosis in both II You 718 and II You 838 at different levels.