中间偃麦草染色体臂7Ai-1L端体的细胞遗传学鉴定及显微分离与克隆

Identification of Ditelosome 7Ai-1L of the Chromosome Arm in Thinopyrum intermedium by Cytogenetic Methods and its Microdissection and Microcloning

利用细胞遗传学的方法 ,在确认测试材料根尖体细胞有丝分裂中期染色体数及花粉母细胞 (pollenmothercell,PMC)减数分裂期染色体行为的基础上 ,通过对测试材料与普通小麦的杂种F1PMC染色体配对构型的观察 ,并结合目标染色体所应具有的黄矮病抗性及芽鞘颜色的鉴定 ,证实了测试材料中的端体为目标染色体臂7Ai 1L。在此基础上显微分离、扩增了该染色体臂 ,对扩增产物进行了连接、转化、克隆 ,初步构建了 7Ai 1L的DNA文库。对文库中部分阳性克隆进行Southern杂交分析 ,获得 6个中间偃麦草特异的序列。

Cytogenetic methods were employed in this study. After mitotic count and meiotic observation, the exact chromosome numbers and their behavior in the tested material were confirmed. The chromosome configuration of the PMC of the hybrids between tested material and common wheat were observed then. Combining identification for the BYDV resistance and the coleoptile color, the target chromosome should have. The results showed that the ditelosomes in this material were the target chromosome arms 7Ai-1L. The chromosome arms then were microdissected and microcloned. A DNA library of 7Ai-1L had been constructed. Six specific sequences of Th. intermedium were isolated by Southern blot analysis.