Studies On The Characteristics And The Regulation Of Nitrogen Metabolism In Different Protein Content Rice

Studies on the Characteristics and the Regulation of Nitrogen Metabolism in Different Protein Content Rice ABSTRACT The overstock of early rice in south China is standing out increasingly. Meantime, the raw material of forage industry in south China is hard up. This problem can be handled by developing forage rice. Different protein content rice varieties were used as samples in this paper. Key enzymes (NR, OS, Protease) aCtiVtiOP in lear and abaraetcv~stics qfprQtcrn accumulation in srarn were studied. Mcanwbile, carboxymcthyl chitosan was used as a kind of regulation agent. The results showed that: I. In different seasons, the changing trends of key enzymes activities of nitrogen metabolism in top 3 leaves were similar in different varieties. The key enzymes of nitrogen metabolism in high protein content varieties are more active than those in low protein content varieties. a 2. In different seasons, the amount of total nitrogen content in top 3 leaves in different varieties decreased during the procession of grain maturity. The transmitted nitrogen was used to synthesize protein in rice grain. High protein content varieties can degrade and transmit more nitrogen than low protein content varieties. 3. The amount of total nitrogen content per unit dry weight of grain decreased during the procession of grain maturity. This indicated that the protein synthesis is very active and the amount of different kinds of enzymes in early stage of grain maturity is much more than those of later stage. In later stage, the key enzymes activities decreased remarkably and the synthesis of protein was slower than that of starch. So the total nitrogen content per unit dry weight was lower and lower. 4.Under the treatment of carboxymetbyl cbitosan, the key enzymes activities of top 3 leaves were increased remarkably. This showed that carboxymethyl chitosan could regulate protein metabolism in nce. 5.Rice protein synthesis depends on key enzymes of nitrogen metabolism.