基于PSY2基因单碱基突变的木薯薯肉颜色分子标记开发与利用

Development and Utilization of Cassava Root Color Marker Basing on a Single Nucleotide Mutation in PSY2 Gene

木薯块根颜色是消费者关注的重要性状之一,薯肉颜色主要受八氢番茄红素酶PSY2基因控制。为了快速判断木薯块根肉质颜色,本研究基于编码八氢番茄红素合成酶基因的突变位点PSY2-572,开发出1个单核苷酸扩增多态性(SNAP)标记,可快速检测木薯块根肉质颜色。利用该PSY2-SNAP标记鉴定出的新选048自交群体和62个育种中间材料的基因型均能和表型吻合,如PSY-F1/PSY-R引物对能扩增出388 bp的条带,则木薯材料为白肉;如PSY-F2/PSY-R引物对能扩增出388 bp的条带,则木薯块根肉质为深黄色;如PSY-F1/PSY-R和PSY-F2/PSY-R均能扩增出388 bp的条带,则木薯块根肉质为黄色。此外,利用PSY2-SNAP鉴定国家木薯种质圃中的45份可食用品系基因型,发现其中存在新的黄色薯肉种质资源。综上,本研究开发的PSY2-SNAP是一个具有育种价值的薯肉颜色分子标记,可为木薯分子标记辅助选择奠定一定的理论基础。

The cassava root color is one of the important traits to attract consumers.Root color is mainly determined by the Phytone Synthase 2 in cassava.In order to determine the color of flesh cassava root efficiently,a single nucleotide amplified polymorphic(SNAP)marker was developed based on the mutation of PSY2-572 in PSY2,which can be used to detect the flesh color of cassava root quickly.The genotypes of Xinxuan 048 inbred population and 62 breeding intermediate materials identified by the PSY2-SNAP were consistent with the phenotype we observed.If the PSY-F1/PSY-R primer pair could amplify a 388 bp PCR product,the cassava root would be white flesh,if the PSY-F2/PSY-R primer pair could amplify a 388 bp PCR product,the cassava root would be dark yellow,if both of PSY-F1/PSY-R and PSY-F2/PSY-R primer pairs could amplify 388 bp PCR product,the cassava would be yellow flesh.In addition,the genotypes of 45 edible lines in the natural cassava nursery were identified by PSY2-SNAP,and some new yellow-color cassava germplasms were found.In summary,the PSY2-SNAP developed in this study is a valuable color molecular marker of cassava root in breeding,which can lay a theoretical foundation for molecular marker assisted selection of cassava.