小麦花后籽粒抗性淀粉含量累积动态分析

为了给小麦抗性淀粉(Resistant starch,RS)的生物合成调控提供依据,以3个抗性淀粉含量差异较大的春小麦品种新春24、安农9912和E28为材料,分别测定其花后6、9、12、15、18、21、24、27、30 d籽粒中的抗性淀粉含量,并进行了净遗传增量的估算.结果表明,三个品种的抗性淀粉含量在籽粒灌浆期均呈现双峰曲线变化.新春24籽粒的抗性淀粉含量在花后15d达到第一个累积高峰,而安农9912和E28籽粒的抗性淀粉含量在花后18 d后才达到第一个累积高峰(其中E28的峰值最高),花后30 d安农9912和新春24再次达到第二个累积高峰.通过各时期籽粒抗性淀粉含量净遗传增量的变化可以了解与抗性淀粉合成相关基因的表达量和效果.本研究结果显示,控制抗性淀粉含量的基因在整个籽粒灌浆时期均有表达,不存在时间上的间断,并且控制抗性淀粉合成的基因在灌浆末期的表达量对成熟籽粒抗性淀粉的含量起重要作用.

Dynamic Analysis of Resistant Starch Content in Wheat Kernels after Anthesis

This experiment was aiming at providing theoretical basis for in depth studying the wheat Resistant starch (RS) and providing guidance for high RS quality wheat breeding and cultivation of new cultivars. In this study, three spring wheat cultivars Xinchun24, Annong9912 and E28, which had great significant difference in RS content, were investigated at 6 d, 9 d, 12 d, 15 d, 18 d, 21 d, 24 d, 27 d and 30 d after flowering and it Net Genetic Incremental was estimated at the same time. The results showed that the RS content of three spring wheat cultivars showed a bimodal curve during the grain filling period. RS content in Xinchun24 reached the first cumulative peak at 15 day after pollination (DAP). RS content of Annong9912 and E28 reached the first cumulative peak at 18 DAP (E28 with the highest peak). In addition, RS content in Annong9912 and Xinchun24 reached the second cumulative peak at 30 DAP. Through the net increment of genetic changes in the content of resistant starch in grains, the expressions and effects of the resistant starch synthesis related genes could be understood. The results showed that the expressions of genes controlling RS content were continuously during the whole grain filling period without time break. Furthermore, the expression amount of these genes played a very important role in RS content of mature grain in the late filling stage.