苹果砧木耐盐性基因SRAP标记的鉴定及序列分析

摘要

筛选苹果砧木耐盐相关的分子标记，为耐盐品种选育的辅助选择提供理论依据。以西府海棠× S19杂交组合的 F1为试材，采用 BSA法，筛选与耐盐基因连锁的 SRAP 标记，通过144棵 F1单株对标记进行分析验证，并对标记进行测序及序列分析。获得了4条与耐盐基因连锁的 SRAP标记，验证分析表明，4条标记的分子鉴定结果与水培筛选结果的吻合率为81.94%~92.36%。序列分析表明，4条标记的序列全长为139~233 bp，Ⅰ序列与红叶石楠中编码ATP合酶β亚基有较高相似性，相似度为98%，其他序列分别可能与梨类受体蛋白激酶、苹果肌球蛋白及苹果 UDP-糖基转移酶存在部分相似性。4条 SRAP标记可用于苹果砧木耐盐性分子鉴定和耐盐基因克隆的研究。%The study was conducted to screen molecular markers of salt-tolerance gene in apple rootstock, which providing a theoretical basis for molecular assistant selection breeding in plants salt-tolerance. F1 of Malus ni-cronalus × S19 were used to screen markers linked to salt-tolerance gene by BSA method and SRAP technology. Four pairs of primers(Me1Em2,Me1Em8,Me6Em12 and Me6Em14)were screened from 128 ones,which ex-pressed polymorphism in parents and DNA pools and totally produced 4 polymorphic fragments. The four pairs of primers were tested by 144 F1 hybrid seedings,and the coincidence rate between hydroponic screening and the SRAP analysis were between 81. 94% and 92. 36%. The length of the 4 polymorphic fragments(Ⅰ,Ⅱ,Ⅲ andⅣ)was between 139 bp and 233 bp by cloning and sequencing. Sequence alignment revealed that sequenceⅠhad relatively highly identity with ATP synthase beta subunit gene( ATP-β)from Photinia fraseri,and there was an i-dentity of 98% for nucleotide sequence. Additionally,other sequences showed partial identity with probable recep-tor-like protein kinase from Pyrus × Bretschneideri,myosin from Malus donestica,and UDP-glycosyltransferase from Malus donestica,respectively. The 4 markers selected not only could be used in molecular identification of salt toler-ance,but also provide a foundation to clone salt-tolerance gene for apple rootstock.