本文旨在论证杂交稻“粒间顶端优势”现象。研究结果表明杂交稻一穗中强势粒对弱势粒的灌浆有抑制作用。去除强势粒 ,弱势粒灌浆即可明显改善。外源 IAA可部分代替强势粒对弱势粒灌浆的抑制作用 ,其表现类似水稻主茎与分蘖间的顶端优势现象。HPL C分析籽粒内源 IAA的结果表明强弱势籽粒中内源吲哚乙酸水平差异明显 ,这种差异似与强弱势粒对营养器官 (剑叶 )的内源 IAA吸收能力及籽粒合成吲哚乙酸的能力有关 The purpose of this paper is to demonstrate the “top edge of grain” phenomenon in hybrid rice. The results showed that the strong grains in a panicle of hybrid rice had an inhibitory effect on the grain filling of the weaker grains. Removal of strong grains, weak grain filling can be significantly improved. Exogenous IAA can partially replace the inhibitory effect of strong grains on undergrained grain filling, which behaves like the top superiority between the main stem and tiller of rice. HPL C analysis of endogenous IAA results showed that strong and weak endogenous endogenous levels of indole acetic acid difference significantly, this difference is similar to strong and weak potential organs of vegetative organs (Jian Ye) endogenous IAA absorption capacity and grain synthesis of indole acetic acid Related to the ability