关键词: 控释氮肥, 杂交水稻, 蛋白质, 氨基酸, 酶活性

Abstract: The protein and amino acids contents and components in brown rice,the activities of nitrate reductase(NRase),glutamine synthetase(GS)and protease in functional leaves and grains in hybrid rice as regulated by controlled release nitrogen fertilizer(CRNF)were analyzed by using Baliangyou 100(early hybrid rice)and Weiyou 46(late hybrid rice)as materials.There were three treatments:1)Control(no nitrogen applied,CK);2)Urea(90 kg N/hm2 in early hybrid rice,105 kg N/hm2 in late hybrid rice,2/3 N as basal application,1/3 N as top-dressing at the tillering stage,Urea);3)Controlled release nitrogen fertilizer(90 kg N/hm2 in early hybrid rice,105 kg N/hm2 in late hybrid rice,all N as basal application,CRNF).Results showed that total protein and complex protein contents in brown rice of both the early and late hybrid rice were significantly higher in CRNF treatment than in urea treatment.Glutelin and glutelin/prolamine ratio were increased significantly under CRNF treatment for both of the hybrid rice combinations.Total amino acids,essential amino acids and limited amino acids contents in brown rice under CRNF treatment for both of the hybrid rice combinations were increased greatly compared with urea treatment.Dynamic changes in NRase and protease activities in functional leaves and glutamine synthetase activities in grains for both of the hybrid rice combinations followed the same tendency.Moreover,CRNF application was favorable to maintain the activities of NRase,GS and protease at high level.CRNF application had obvious regulation for key enzyme activities involved in nitrogen metabolism in functional leaves and grains of hybrid rice,so it might contribute to a significantly enhanced grain yield,protein content and amino acids content of hybrid rice comparing with urea application.

Key words: controlled release nitrogen fertilizer, hybrid rice, protein, amino acid, enzyme activity