亚种间杂交稻籽粒灌浆特性及其生理机制

GRAIN-FILLING CHARACTERISTICS AND PHYSIOLOGICAL MECHANISM OF INTERSUBSPECIFIC HYBRID RICE

亚种间杂交稻强、弱势粒灌浆表现为明显的异步灌浆型 .强势粒和谷粒充实率好的组合 ,灌浆初期籽粒中蔗糖含量低 ,淀粉含量高 ,弱势粒和谷粒充实率差的组合结果则相反 ;灌浆初期籽粒中的蔗糖转化酶活性、Q酶活性以及细胞分裂素含量 ,强势粒高于弱势粒 ,谷粒充实率好的组合高于谷粒充实率差的组合 .

The filling process of superior and inferior grains of intersubspecific hybrid rice combinations (IHRCs) was obviously asynchronous. Superior grains (SGs) and the IHRC with good grain plumpness had low sucrose content and high starch content, but the results were reversed for inferior grains (IGs) and the IHRC with poor grain plumpness. At early grain filling stage, sucrase activity, Q enzyme activity and cytokinin content in SGs, or the IHRC with good grain plumpness were higher than those in IGs, or higher than those in the IHRC with poor grain plumpness. The results suggest that low physiological activities of grains at early filling stage account for poor grain plumpness in some IHRCs.