谷子糯质基因共分离分子标记的研究

摘要

为得到一种鉴别糯质谷子的分子标记方法，用于优质谷子糯质资源的利用及糯质品种的选育。通过对糯性谷子十里香与梗性谷子豫谷1号配制的 F2群体的 F3种子胚乳进行碘液检测，结果显示：深蓝色与棕红色胚乳单株数的比例符合3∶1，说明糯质对梗质是由单基因控制的隐性性状。利用糯质分型引物对十里香基因组进行 PCR 扩增和产物测序，结果表明，十里香的糯性是由Ⅳ型糯质基因控制，即由 TSI-2转座子插入到淀粉合成酶基因（Si006103m）内元1形成。根据该糯质基因设计出2对 InDel 标记引物 waxy-TSI2／int1和 waxy-int1-1 F ／4R，扩增谷子基因组 DNA，若 waxy-TSI2／int1引物组合能扩增出984 bp 的扩增片段，并且 waxy-int1-1 F ／4R 引物组合不能扩增出540 bp 的扩增片段，则该材料为含Ⅳ型糯质基因的糯质谷子。最后，利用该标记组合从100份谷子资源中鉴定到2份属于Ⅳ型糯质基因控制的糯质材料。可见，该标记组合可以准确鉴别谷子Ⅳ型糯质基因。%The study provided a molecular marker technology to identify the waxy foxtail millet,which could be used to utilize the excellent waxy resources of foxtail millet and to breed the waxy varieties.Firstly,through the io-dine solution detection of the F3 seeds endosperm from F2 constructed from the hybridization of waxy foxtail millet, Shilixiang,and non-waxy foxtail millet,Yugu 1 .Results showed that the ratio of plant numbers with dark blue and brownish red endosperm was 3 ∶1 ,indicated that the waxy phenotype was a recessive trait controlled by a single gene.Then using waxy genotyping primers,the genomic DNA of Shilixiang was amplified by PCR and the products were sequenced.The results showed that the waxy trait was controlled by a Ⅳ type waxy gene,namely a TSI-2 trans-poson was inserted into the first intron of the starch synthase gene (Si006103m).Therefore,the InDel molecular markers,waxy-TSI2 /int1 and waxy-int1 -1 F /4R,were developed based on the gene sequence of Si006103m,and then the genomic DNA of foxtail millet was amplified by them.If there was an product with 984 bp amplified by the waxy-TSI2 /int1 primer and no product with 540 bp amplified by the waxy-int1 -1 F /4R primer,the material was i-dentified as a waxy foxtail millet containing the type Ⅳ waxy gene.Furthermore,we identified 2 waxy materials con-trolled by the Ⅳ type waxy gene from 100 foxtail millet resources using two pairs of waxy primers.Therefore,the In-Del markers can be used to accurately identify the Ⅳ type waxy gene from foxtail millet.