IFS转基因大豆的鉴定及高异黄酮植株的筛选

大豆异黄酮是一种广泛应用的保健性活性物质,近年来已成为衡量大豆品质的重要指标之一。异黄酮合酶是大豆异黄酮合成途径中的关键酶基因之一,其在植物中的表达效率直接影响异黄酮含量。为进一步验证该基因的功能并获得高异黄酮稳定遗传转基因植株,本试验基于已有的IFS转基因材料开展研究。将其扩繁至T2代,考种分析植株农艺性状,发现转基因植株的性状指标未发生明显变化,PCR鉴定IFS转基因后代的结果显示:在125株转基因植株中,60株为阳性,占比48%,说明IFS在后代中可稳定遗传。选取IFS转基因吉林35、Willimas 82品种T2代的41株,利用改良后的三波长法测定籽粒中大豆异黄酮的含量,结果显示:IFS转基因植株的平均异黄酮含量为1.2 mg·g~(-1);其中15株的异黄酮含量高于非转基因植株,占比达到36.6%,说明从转入IFS基因转基因大豆能够筛选出高异黄酮植株。本研究获得了稳定遗传的高异黄酮植株,为大豆遗传育种提供优异的种质资源;改良后的三波长法较原有方法更为精准、快速。

Identification of IFS Transgenic Soybean and Selection of Plant with High Isoflavones

As a healthy active substances,soybean isoflavones have obvious effects in the prevention of cancer,osteoporosis,cardiovascular disease and women＇s climacteric syndrome.IFS is one of the key enzymes in the pathway of isoflavone biosynthesis and it had a positive effect on the content of isoflavones in soybean seeds,but we still haven＇t get stable and efficient transforms.Therefore,it is very important to improve the content of soybean isoflavones by studying isoflavone synthase pathway.In this study,after propagating IFS transgenic plants to T2 generation,physiological indexes in transgenic plants had no obviously changes by agronomic traits analyzing.Mter identifying IFS transgenic soybeans by RT-PCR analysis,there were 60 IFS transgenic soybeans in 125 plants,accounting for 48％.This result indicated that IFS was stablily inherited in offspring.We used the modified three wavelength method to measure the isoflavone content and results showed that the average isoflavone content was 1.2 mg·g-1 in IFS transgenic plants.Among the 41 IFS positive plants,isoflavone content of 15 individual plants were higher than that of the non-genetically modified plants,which accounted for 36.6％.The IFS had a certain effect on the improvement of isoflavone content and it is possible to select plants with high isoflavones in IFS transgenic soybeans.This study clarified the effect of IFS on the content of isoflavones in transgenic soybean and obtained transgenic soybean containing much soybean isoflavones and provided an excellent germplasm resource for soybean breeding at the meantime.In additionally,the improved three wavelength method was more accurate and faster.