小麦赖氨酸加苏氨酸的胁迫反应与抗性基因型筛选

为探讨不同小麦品种对赖氨酸和苏氨酸的胁迫反应,筛选抗性基因型,在试管中添加2～4 mmol/L赖氨酸和苏氨酸,培养小麦离体胚,10~40 mmol/L直接胁迫种子发芽,对国内外529份小麦优良品种和常用亲本材料处理,筛选其抗性基因型,并用高效液相色谱法检测胁迫处理材料的游离氨基酸和全氨基酸。结果表明,约有20%的基因型对赖氨酸和苏氨酸具有抗性,试管植株生长量差异显著,但籽粒中游离赖氨酸和全赖氨酸含量差异不显著。这说明：测试的品种中具有生长中对赖氨酸和苏氨酸的抗性,但该抗性不直接影响种子中赖氨酸和苏氨酸含量。小麦高赖氨酸品质育种是一项长期的改良任务,在筛选和转移优良高赖氨酸基因的基础上,应重点研究诱导种子灌浆期间天冬酸途径持续超量表达和产物的有效积累。试验结果还显示不同品种存在本身潜在的特殊氨基酸含量特性。

Stress Response and Resistant Genotypes Screeningto Lysine plus Threonine in Wheat

In order to research the stress response to lysine and threonine and screen the resistant genotypes, 529 wheat varieties and parent materials from China and foreign countries were cultured in N6 medium in which lysine and threonine at the concentration of 2-4 mmol/L were added, wheat seeds were stressed in the solution added L lysine and L threonine of 40 mmol/L to select the resistance genotypes, and the content of free and total amino acids in seeds of different resistance genotypes were detected using the method of HPLC. The results showed that about 20% of the wheat genotypes were resistant to lysine and threonine, and significant difference was found in the growth of plants, but the content of free and total lysine were not significantly different.These results indicate that the resistance to lysine and threonine in growth can not directly affect the content of lysine and threonine in seeds. The wheat high lysine breeding is a long term task, and on the base of selection and transfer of the lysine rich genes, the research should focus on the excessive expression for aspartic acid metabolic pathways and the effective accumulation products in the filling stage. The result also shows that special amino acid content advantage is in the different wheat varieties.