糯性小麦研究进展

糯小麦(Waxy wheat)因有高于普通小麦的支链淀粉含量,在食品和工业方面有很大的应用价值和潜力,自发现后就成为各国小麦研究的重点之一.通过多年的努力,人们在糯小麦的遗传机理、育种理论和方法、品质性状及利用等方面的研究都取得了很大的进展,并在1995首次育成了全糯性小麦.糯小麦根据其糯蛋白缺失情况可分为8种类型.控制3个Waxy位点的Wx-A1,Wx-B1和Wx-D1基因分别位于染色体的7AS、4AL和7DS上.3个基因的核苷酸序列长度分别是2 781、2 794、2 862 bp,基因的完全编码区含有11个外显子和10个内含子,在核苷酸序列上三个糯基因彼此之间有惊人的同源性.研究表明,直链淀粉含量和淀粉糊化特性受Wx-B1的影响最大,其次是Wx-D1,Wx-A1蛋白的影响最小.糯小麦的鉴定主要在细胞水平、蛋白质水平、分子水平上进行,I2-KI染色法和SDS-PAGE法是较常见的鉴定小麦糯性的方法.糯小麦野生型与突变型基因组成差异的发现使得分子标记技术在糯小麦的选育中得到了极大的发展和利用.

Progress in Research of Waxy Wheat

Waxy wheat was an important research focus in many countries because of its utilization value and potential end use of its flour in food and industry.Researchers have got great progress in waxy wheat on its hereditary theory,breeding theory and method,quality properties and its utilization during the past decades.In 1995 Nakamura bred the first whole waxy wheat variety in the world.There were 8 types of waxy wheat according to the presence or absence of its waxy protein.The genic loci of Wx-A1,Wx-B1 and Wx-D1 were found on chromosomes 7AS,4AL and 7DS respectively.The lengths of the three genes were 2 781,2 794 and 2 862 bp,respectively.The entire coding regions consisted of 11 extrons and 10 introns.There were significant homologies among those three genes.The effects on amylose content and starch pasting properties in common wheat were Wx-B1 >Wx-D1>Wx-A1.The identification techniques of waxy wheat was mainly on cell,protein and molecular level.The tools of I2-KI and SDS-PAGE were usual methods used to identify the waxy wheat,the technologies of molecular marker was used to identify the waxy wheat after the difference between wild types and mutation types of waxy genes has been found.