小麦-中间偃麦草衍生后代的细胞学和SSR标记鉴定

Cytologic and SSR Identification of Derivatives from Wheat-thinopyrum intermedium

为了鉴定小麦与八倍体小偃麦的杂交组合NZ2W5的衍生后代中是否含有中间偃麦草的遗传物质,利用细胞学和SSR技术对该组合的12个衍生单株进行了鉴定。结果表明,NZ2W5组合衍生后代的根尖细胞染色体数目均为2n=42,花粉母细胞减数分裂中期I染色体构型均为2n=21II。以相关亲本中间偃麦草、小麦-中间偃麦草部分双二倍体远中2、普通小麦合作2号和阿勃以及衍生后代为材料,选取均匀分布于小麦各条染色体上的480个SSR标记进行分析,结果表明,Xbarc008、Xbarc195、Xwmc489、Xcfb3440、Xwmc331和Xgwm608等20个标记在中间偃麦草中具有特异条带,其中定位在小麦4D染色体上的标记Xwmc331可以在NZ2W5组合衍生的12个单株中检测到中间偃麦草119bp的特异条带。研究结果表明,NZ2W5组合衍生后代的细胞遗传学基本稳定,携带中间偃麦草的遗传物质,涉及的外缘遗传物质可能同源于小麦的第四部分同源群。

In order to identify the chromatin of Thinopyrum intermedium in wheat-Th.intermedium derivatives,12 individuals from the combination NZ2W5 were analyzed wtih cytological and SSR markers.Chromosome numbers of NZ2W5 derivatives in root tip cells were 2n=42 and chromosome configuratiuon of that at PMC M I were 2n=21II.Using Th.intermedium,wheat-Th.intermedium partial amphiploid Yuanzhong 2,common wheat Hezuo 2 and Abbondanza and 12 derivatives as materials,480 SSR（simple sequence repeat） markers were used to investigate the polymorphisms among parents and to detect the alien chromatin in derivatives.20 markers,such as Xbarc008,Xbarc195,Xwmc489,Xcfb3440,Xwmc331 and Xgwm60,had specific bands in Th.Intermedium.Marker Xwmc331 located on wheat 4D could detect an 119 bp specific band of Th.Intermedium in 12 individuals.The results showed that 12 derivatives of NZ2W5 were cytogenetically stable and had Th.intermedium chromatin,it was possible that the alien chromation was homologous to the homoeologous group 4.