亚种间杂交稻谷粒灌浆特性与籽粒充实度的研究

Studies on the Filling characteristics and the plumpness of Grains in Inter-subspecific Hybrid Rice

对水稻亚种间杂种亚优 2号的谷粒灌浆特性和籽粒充实度进行了研究 ,分析了亚种间杂种籽粒充实度差的主要原因 ,并提出了改善籽粒充实度的对策。

With the intervarietal indica combination Weiyou 46 as the control, the inter subspecific rice hybrid Yayou 2 was studied on the grain plumpness in 1991. The results indicated that Yayou 2 exhibited the characteristics of 'multi-startings of filling” and 'multi-peaks of filling' of grains with slower filling rate; and the later the grains started filling, the longer it to get groains fully filled. It was also found that the later starting of filling and slower filling rate were the basic reason to cause a large number of empty and sparing grains in the intersubsecific rice hybrid. Futhermore, the research on the source of filling materials showed that the accumulated photosynthate in stem and leaf sheath before heading and the photosynthate produeed by the flag leaf and the second top leaf were the primary source of filling substances. By way of cultural manage ment, the accumulation of dry matter before heading and its transferring rate in the filling stage can be increased, resulting in the improvement of grain plumpnessd.