一个小麦-中间偃麦草二体代换系的鉴定与分析

中间偃麦草在小麦改良中具有重要利用价值。本研究利用基因组原位杂交(GISH)、高分子量谷蛋白亚基电泳(SDS-PAGE)和分子标记技术对小麦-中间偃麦草衍生系中209进行鉴定。结果表明,中209的42条染色体中含有2条中间偃麦草染色体,是小麦-中间偃麦草二体代换系;分子标记检测发现,小麦7A染色体上的6个SSR引物Xcfa2028、Xwmc422、Xwmc65、Xbarc127、Xbarc174和Xgwm60在小麦亲本合作2号中均扩增出清晰的DNA条带,而在中间偃麦草和中209中均未扩增出任何条带,表明中209可能缺少了小麦7A染色体;小麦第7部分同源群的SSR标记Xwmc488和STS标记Xmag1715分别在中209中扩增出中间偃麦草的特异带,推断其含有的中间偃麦草染色体与小麦第7同源群染色体存在部分同源关系;SDSPAGE表明中209含有5+10亚基。

Identification of a Wheat Thinopyrum intermedium Substitution Line Zhong 209 Based on SDS PAGE, Cytology and Molecular Markers

Thinopyrum intermedium has many valuable genes for wheat genetic improvement. The aim of present study was to identify a novel wheat Thinopyrum intermedium substitution line (Zhong 209) using genomic in situ hybridization (GISH), sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE), SSR, EST SSR and STS marker analysis. The results indicated that the chromosome number in root tip cell of Zhong 209 was 42 with 2 Th. intermedium chromosomes, indicating that it was a wheat Th. intermedium substitution line. Each of six SSR markers ( Xcfa2028, Xwmc422, Xwmc65, Xbarc127, Xbarc174 and Xgwm60) on the chromosome 7A amplified a clear band in the wheat parent Hezuo 2, but no products was amplifed in Th. intermedium and Zhong 209, indicating that wheat chromosome 7A was absent in Zhong 209. Two markers from the group 7 of wheat, including a SSR marker ( Xwmc488) and a STS marker ( Xmag1715), revealed a specific band of Th. intermedium in Zhong 209, which confirmed that the two Th. intermedium chromosomes in Zhong 209 were homoeologous to the group 7 of wheat. The HMW glutenin subunit, 5+10, was further identified in Zhong 209.