小麦-中间偃麦草部分双二倍体“中5”的外源染色体的鉴定

Identification of Alien Chromosomes in Triticum aestivum-Thinopyrum intermedium Partial Amphidiploid-Zhong 5

应用染色体分带(C-带)-分子原位杂交技术对普通小麦-中间偃麦草(Thinopyrum intermedium 2n=42,E_1E_1E_2E_2XX)部分双二倍体“中5”(2n=56)的外源染色体进行了鉴定分析。染色体分带结果表明:“中5”的7对中间偃麦草染色体不显带或显示出与受体小麦亲本染色体相似的带型,单靠带型很难准确地鉴定出这7对外源染色体。分带处理后进行分子原位杂交鉴定出“中5”的7对外源染色体,并发现其中一对染色体发生了罗伯逊氏易位(Robertsonian translocation)。表明染色体分带技术与分子原位杂交技术的有机结合,可以大大提高染色体的鉴定水平。

A partial amphidiploid wheat-Thinopyrum intermedium, Zhong 5 (2n=56) was analysed by sequential C-banding and genomic in situ hybridization. The result indicated that seven pairs of Th. intermedium chromosomes in Zhong 5 appeared no band or similar bands to the chromosomes of common wheat. So, it is impossible to identify the seven pairs of alien chro mosomes only according to C-banding. However, the seven pairs Th. intermedium chromosomes in Zhong 5 were identified, and a pair of Robertsonian translocation chromosomes of wheat Th. intermedium was detected by sequential C-banding and genomic in situ hybridization. The results suggested that it is the best way to combine C-banding and in situ hybridization to identify alien chromosome in wheat background.