水稻籽粒蛋白质含量选择对杂交后代蛋白质含量及氮代谢关键酶活性的影响

 以籽粒蛋白质含量有显著差异的杂交后代及亲本为材料，分析了灌浆成熟过程中叶片蛋白水解酶和籽粒谷氨酰胺合成酶活性以及籽粒可溶性蛋白质含量的变化动态。结果表明，在籽粒蛋白质含量相近的亲本衍生的杂交后代中，通过籽粒蛋白质含量的连续定向选择不仅可以获得籽粒蛋白质含量和叶片蛋白水解酶活性及籽粒谷氨酰胺合成酶活性明显变高或变低的杂种后代，而且可获得蛋白质含量和酶活性超亲的后代；稻米蛋白质含量与灌浆过程中的叶片蛋白水解酶活性呈正相关， 籽粒可溶性蛋白质含量与籽粒谷氨酰胺合成酶活性呈显著负相关。

Effects of Grain Protein Content Selection on Protein Content and Key Enzymes Activities for Nitrogen Metabolism in Rice Hybrid Progenies

The japonica parents (Tong 769 and Xixuan 1) and their hybrid progenies, significantly differed in protein content in grains, were investigated to reveal the activities of protease in leaves and glutamine synthetase in grains and the dynamic alteration of soluble protein content in grains during grain filling. The results showed that the protein content in rice of the parents was near to each other, however, hybrid progenies with different contents of protein in grains and higher or lower activities of protease in leaves and glutamine synthetase in grains were acquired by consecutively directed selection of the grain protein content in their hybrid progenies. Moreover, the enzyme activity and protein content in grains exceled their parents during grain filling. The content of protein in rice and the activitiy of protease in leaves were positively related, and the content of soluble protein and activity of glutamine synthetase in grains were negatively related to some extent.