小麦与高冰草体细胞杂种后代的核基因组和叶绿体基因组的遗传特征

以小麦(Triticum aestivum L.)与高冰草(Agropyron elongatum(Host)Nevski)体细胞杂种同一个克隆来源的F2-F6自交系Ⅱ-2、Ⅱ-Ⅰ-8以及由Ⅱ-Ⅰ-8 F2分离形成的8-1(F3-F6)为材料,利用小麦叶绿体基因组的微卫星(Microsatellite)特异引物及随机扩增多态性DNA(RAPD)引物进行分析.结果表明,杂种株系的叶绿体基因组组成一致,均以小麦叶绿体基因组为主,仅在rpl14和rpl16基因的间隔序列中检测到双亲的特征带,表明有高冰草的叶绿体DNA在杂种中存在,并稳定遗传至第六代.RAPD分析表明,不同杂种株系中存在不同的高冰草核DNA片段,核基因组在传代中基本稳定.

Heredity of Chloroplast and Nuclear Genomes of Asymmetric Somatic Hybrid Lines Between Wheat and Couch Grass

hloroplast microsatellite primers of wheat (Triticum aestivum L.) and random primers were employed to identify the chloroplast and nuclear genomes of three selfed linesⅡ-2, Ⅱ-Ⅰ-8 (F₂-F₆) and 8-1 (F₃-F₆) ( segregated from Ⅱ-Ⅰ-8 of F₂), which were derived from the same asymmetric somatic hybrid clone between Triticum aestivum L. cv. Jinan 177 and Agropyron elongatum (Host) Nevski. The results showed that the chloroplast genomic components of the three lines were consistent and dominated by that of wheat. Bands characteristic to both parents were only detected in the sequence of the intergenic region between rpl14 and rpl16 of the chloroplast genome, suggesting the existence of chloroplast DNA of A. elongatum in those hybrids. Furthermore, this exogenous integration of chloroplast DNA was passed to F₆ stably. RAPD analysis showed that there were different DNA fragments of A. elongatum in different lines. However, the nuclear genome basically remained stable during passage.