水稻籽粒蛋白质积累特性的研究

STUDY ON THE CHARACTERISTICS OF PROTEIN ACCUMULATION IN RICE GRAIN

以不同蛋白质含量的水稻品种为试材,研究了水稻籽粒蛋白质的积累特性。结果表明,单粒蛋白质含量随籽粒发育而增加,而单位干重的蛋白质含量却以开花后7天最高,14至21天降至最低,以后又逐步上升,28天趋于稳定。籽粒蛋白质的积累受叶片氮素降解和运转的影响,高蛋白质含量比低含量的品种具更强的叶片蛋白酶活性,叶片氮素的降解能力更强。并且,前者籽粒中游离氮基酸含量高于后者。籽粒蛋白质的积累也受环境条件的影响,抽穗期施氮可以提高籽粒蛋白质含量。

Rice(Oryza sativa L.)varieties with different protein contents were employed to studythe characteristics of protein accumulation in the grain.Protein content per grain wasshown to increase with the development of the grain.When expressed in terms of dryweight,protein content in grain had the highest value 7 days after flowering(DAF),thelowest value 14-21 DAF,and increase thereafter to a stabilized level about 28 DAF.Theaccumulation of grain protein was affected by leaf nitrogen degradation and translation.Developing grains of rice with high protein percentage tended to have higher proteinase inleaf,leaf nitrogen degradation ability and higher free amino N levels in the grain.The pro-tein accumulation of rice grain was affected by environmental factors,suggesting thatapplication of nitrogen fcrtilizer at heading of the plants might increase protein content ofthe grain.