中国特有小麦的易位染色体鉴定

Identification of Translocated Chromosomes in Chinese Endemic Wheat Accessions

中国特有小麦在研究小麦进化中具有重要价值。本研究利用多色基因组原位杂交和多色荧光原位杂交技术,发现供试的7份中国特有小麦品种均有一对4AL-5AL-7BS易位染色体,该易位是普通小麦和四倍体小麦的物种特异易位。在云南铁壳麦AS335中,还发现另外2对以前未报道的1BS·1BL-2DL和2DS·2DL-1BL易位。由于在另外1份云南铁壳麦AS336中不存在这两对易位,表明它们不是云南铁壳麦亚种特异的易位。这两对易位是相互易位,但是易位点不在着丝点,而在染色体长臂中部。本文还讨论了相互易位的产生、在物种进化和适应中的价值及其下一步研究的问题。

Chinese endemic wheat accessions with special geographical distributions are important to study the evolution of common wheat. In this study, multi-color genome in situ hybridization and multi-color fluorescence in situ hybridization were used for identification of translocated chromosomes in Chinese endemic wheat accessions. The results indicated that all the seven Chinese endemic wheat lines analyzed had the chromosome translocation of 4AL-5AL-7BS, which was the interspecies-specific translocation of common wheat and emmer wheat. We found additional two new pairs of transloca- tions, i. e. 1BS · 1BL-2DL and 2DS · 2DL-1BL, in Yunnan hulled wheat AS335. However, the trans- locations were not found in another Yunnan hulled wheat AS336, thus indicating that they were not subspecies-specific. The two pairs of translocations were reciprocal translocations and the breakpoints were not located in centromeric regions but in the middle of long arms of the chromosomes. The pro- duction of reciprocal translocations and their values in species evolution and adaptation as well as fol- lowing works were discussed.