奉节脐橙芽变株系的AFLP分析

采用AFLP分子标记技术分析了奉节脐橙的低酸和晚熟芽变株系基因组DNA的遗传差异,并对找到的芽变特异片段克隆测序和比对分析。64种引物组合对脐橙及其芽变进行选择扩增，共扩增出5336条电泳带，发现与普通的奉节脐橙相比，低酸芽变株系基因组有7条差异带，晚熟芽变株系有2条差异带；DNA比对结果表明：导致奉节脐橙低酸芽变果实低酸的原因，可能与其缺少一种Na+/H+反转运蛋白或其基因发生了突变有关；导致奉节脐橙晚熟芽变晚熟的原因则比较复杂, 似乎与缺少一种花发育蛋白或其基因发生了突变有关，其果实细胞质乌头酸酶基因也可能发生了突变。

Analysis of the Mutants of Fengjie Navel Orange (Citrus Sinensis Osbeck) by AFLP

Genetic variabilities of the low-acid muta nts and late-mature mutant of the Fengjie navel orange were examined by AFLP tec hnology By using 64 pairs of selective primers,5336 bands,among them, 7 spec ific bands in low-acid mutant,2 specific bands in late-mature mutant were detected The sequencing of these specific bands and their Blastp analysis sho w ed :the trait of low acid in fruit in the low-acid mutant of Fengjie navel orang e could result from the deficiency ormutation of the gene encoding Na /H antiporter-like protein, whilethe deficiency ormutation of the genes encoding the flower development protein cycloidea (cyc3) and cytoplasmic aconitate hydratase could be responsiblefor the late mature of late-matu re mutant