小麦不同花位籽粒重差异及其原因分析

通过分析不同品种、不同群体小麦各花位籽粒之间重量的差异,结果表明。2粒小穗粒重差异较小,3粒及3粒以上小穗以第2粒为最重,最高花位籽粒粒重显著低于低位花。不同花位籽粒的灌浆历期相近,灌浆速率差异与粒重一致。高位花由于分化迟,组织结构与活力不如低位花。在获得光合产物的分配上处于劣势。栽培措施可以改变各花位籽粒粒重及平均粒重,但要改变粒重差异较为困难。

WEIGHT DIFFERENCE OF GRAINS AT DIFFERENT POSITIONS AND ITS REASON

Weight difference of grains at different positions in wheat of various cultivars and populations were analysed. The main results were as follows. The grain weight difference in the spikelet with 2 grains was slight. The second grain in a spikelet with 3 or more grains was heaviest and the highest grain was the lightest and significantly lighter than the lower grains. The filling durations of different position grains were similar. Filling rate differences were in consistent with grain weight's. Higher position florets differentiated later, of which organs and activity were worse than lower position florets, so they could only get less photosynthate. Cultural techniques could change the grain weight, but it was quite difficult to change the grain weight difference.