不同栽培法对食用稻子粒氨基酸含量的影响及其机理初探

水稻属于低蛋白作物,稻米的蛋白质含量与氨基酸组成受遗传基因的控制,但环境条件与栽培措施的影响也不容忽视。采用田间小区试验和室内分析相结合的方法,以湘早籼31(早稻)和培两优210(晚稻)组合为材料,探讨了水稻高蛋白高产栽培技术体系、三壮三高栽培法、常规栽培法对稻米氨基酸含量的影响及其作用机理。结果表明,与常规栽培法相比,水稻高蛋白高产栽培综合技术体系能明显提高灌浆中后期水稻功能叶和子粒中谷草转氨酶和天冬氨酸激酶的活性,明显提高糙米氨基酸、人体7种必需氨基酸和蛋白质含量、产量和蛋白质产量;除早稻蛋白质产量外,其他指标与三壮三高栽培法之间差异不显著。水稻高蛋白高产栽培技术体系的早稻糙米的氨基酸含量比三壮三高栽培法、常规栽培法分别提高了4.09%和31.92%,人体7种必需氨基酸的含量分别提高了2.99%和33.06%,赖氨酸(稻米蛋白质的限制性氨基酸,猪的第一限制性氨基酸)的含量分别提高了1.95%1、8.55%,苏氨酸(稻米蛋白质的限制性氨基酸)的含量分别提高了6.54%和31.98%,蛋白氮含量分别提高了6.76%和27.57%,蛋白质产量分别提高了15.72%和38.64%;高蛋白高产栽培技术体系中晚稻糙米的氨基酸含量比三壮三高栽培法、常规栽培法分别提高了2.24%和42.98%,人体7种必需氨基酸的总量分别提高了9.20%和58.05%,蛋白氮含量分别提高了1.74%和26.06%,蛋白质产量分别提高了2.80%和59.42%。

The effects of three cultivation methods on amino acid content of rice grains and preliminary study on its mechanism

Rice is a low protein crop,and the protein content in rice grain is determined not only by its inherent gene,but also by environment factors(such as temperature,light and fertilization) and cultural methods.In this paper,the effects of 3 cultivation methods(high-protein and high-yield integrative cultivation method,San-zhuang-san-gao cultivation method and conventional cultivation method) on amino acid content of rice grains and preliminary study on its mechanism were conducted using the rice type of Xiangzaoxian 31(early rice) and Peiliangyou 210 combination(late rice) by means of field experiment combined with lab analysis in Langli county Changsha city 2004.Glutamicoxalacetic transaminase(GOT) activities and aspartokinase(AK) activities of leaves and grains,and the contents of protein and amino acid in brown rice were analyzed.The results showed that the activities of GOT and AK in functional leaves and grains during the middle and late filling stage,the contents of amino acid,lysine(the restrictive amino acid of protein in rice grain,the primary restrictive amino acid of pig) and methionine(the restrictive amino acid of protein in rice grain),7 kinds of essential amino acid for people(Lys,Thr,Val,Met,Leu,Ile,Phe),protein as well as protein yield in brown rice were improved significantly by high-protein and high-yield integrative cultivation method compared with conventional cultivation method.Except for protein content in early rice grains,other indices were not significant different as under high-protein and high-yield integrative cultivation method and San-zhuang-san-gao cultivation method.The contents of amino acid,7 kinds of essential amino acid for people,lysine,methionine,protein N as well as protein yield in early rice grains under high-protein and high-yield integrative cultivation method were increased over San-zhuang-san-gao method and conventional cultivation method by 4.09% and 31.92%,2.99% and 33.06%,1.95% and 18.55%,6.54% and 31.98%,6.76% and 27.57%,15.72% and 38.64%,respectively.The contents of amino acid,7 kinds of essential amino acid for people,protein N as well as protein yield in late rice grains under high-protein and high-yield integrative cultivation method were increased over San-zhuang-san-gao method and conventional cultivation method by 2.24% and 42.98%,9.20% and 58.05%,1.74% and 26.06%,2.80% and 59.42%,respectively.It is concluded that high-protein and high-yield integrative cultivation method was suitable for rice cultivation.