氨基酸胁迫对小麦种子幼苗生长和体内游离氨基酸水平的影响  

Effect of Amino Acids Stress on Seedling Growth and Level of Free Amino Acids In vivo in Wheat

作　　者：李晓琳[1,2] 孙海燕[1] 魏文变[1,3] 李友勇[1] 

机构地区：[1]河南科技学院河南省高等学校作物分子育种重点学科开放实验室,河南新乡453003 [2]济源市农业科学研究所,河南济源454652 [3]河南中原中农良种有限责任公司,河南新乡453700

出　　处：《中国农学通报》2009年第24期56-61,共6页Chinese Agricultural Science Bulletin

基　　金：河南省自然科学基金"小麦氨基酸生物化学与生物技术改良"(0511031100)

摘　　要：通过观察外源氨基酸直接胁迫小麦发芽幼苗的特征，探讨筛选高特殊氨基酸基因型的新方法。将不同蛋白质含量的小麦品种种子，置于含不同浓度赖氨酸、苏氨酸的N6基本培养基溶液中发芽，观察生长结果并用HPLC方法测定胁迫植株体内游离氨基酸含量。结果发现单个氨基酸到5mmol／L浓度可严重抑制根系生长，但对叶生长抑制较轻；两氨基酸有协同抑制作用。相比较，高蛋白含量基因型品种比低蛋白含量基因型品种可忍耐更高浓度氨基酸胁迫。测定胁迫植株体内游离氨基酸含量，发现胁迫氨基酸比对照高3～10倍，同族氨基酸比对照高2～3倍，相关氨基酸也有1～2倍积累。外源氨基酸可被幼苗吸收积累而产生生长抑制胁迫，不同蛋白含量基因型该胁迫有差异，该差异可作为高蛋白高特殊氨基酸选择标记。Through observing the characteristics of exogenous amino acid directly stressing seedling from the seeds whose protein content were vary to research a kind of new method for selecting new genotype with high essential amino acids in wheat. Seeds germinated in the solution of N6 basic medium add-lysine and threonine at the concentration of 1-5 mmol/L, and then seedling＇s growth were observed and the free amino acids in the plants were detected by HPLC. The results showed that up to 5 mmol/L, the growth of roots of the seedling was suppressed seriously, but that of leaf lightly. When stress was on by synergies of both of lysine and threonine, the cooperation inhibition could be occurrence. In comparison, higher-protein variety might tolerate higher stress concentration of amino acid then low-protein variety. Determination of free amino acid level in the stressed plants found that the stressing amino acid had 3-10 times of accumulation, and the cognation amino acids had 2-3 times of accumulations, and the related amino acids had also 1-2 times of accumulations in comparison with control. These results suggested that exogenous amino acids could inhibit wheat seeds germination and seedling growth by accumulating themselves in vivo, and for the inhibition the there existed difference between the different genotypes, and the difference could be as the marker for selection high protein and high special amino acids genotypes.

关 键 词：小麦 赖氨酸 苏氨酸 胁迫 游离氨基酸 

分 类 号：S312[农业科学—作物栽培与耕作技术]