中文摘要：

LCT1可能是普通小麦Na^＋和Cs^＋吸收的一条重要途径.因此,发掘小麦品种中LCT1自然变异,对于通过常规育种或基因工程提高小麦耐盐性具有重要意义.根据小麦离子转运蛋白LCT1（low-affinity cation transporter）基因cDNA序列（NCBI登录号AF015523）,设计引物对8个小麦品种中LCT多样性进行了初步研究.通过克隆测序和全序列比对在8个小麦品种中发现10种LCT序列,分别命名为LCT2-1,LCT2-2,LCT2-3,LCT3-1,LCT3-2,LCT3-3,LCT3-4,LCT3-5,LCT3-6和LCT3-7.结果表明：10种LCT均与LCT1存在差异.LCT2-1,LCT2-3,LCT3-2,LCT3-3,LCT3-4,LCT3-6和LCT3-7序列发生碱基缺失,缺失均发生在其氨基端.10种LCT序列单碱基突变既有颠换又有转换且均为有义突变.不同小麦品种含有的LCT种类差别较大,其中茶淀红最多（4种）,而百农3217和苏麦3号仅发现1种.在6个小麦品种中都发现LCT3-1.

英文摘要：

LCT1 is probably one of important way of absorbing Na^＋ and Cs^＋ in bread wheat （ Triticum aestivum L. ）. Thereafter, Mining LCT1 natural diversity in wheat is important to improve salt-tolerance by traditional breeding and genetics engineering. PCR primers corresponding to LCT1 cDNA sequence（NCBI Accession： AF015523） was used to the study on LCT natural diversity in eight wheat accessions. Based on LCT sequences blast, 10 kinds of LCT sequences were found. They were named LCT2-1, LCT 2-2, LCT2-3 , LCT3-1, LCT3-2 , LCT3-3 , LCT3-4 , LCT3-5 , LCT3- 6 and LCT3-7. The result showed that 10 kinds of LCT sequences are all different from LCT1. Deletion mutations in LCT2-1, LCT2-3 , LCT3-2 , LCT3-3 , LCT3-4 , LCT3-6 and LCT3-7 were all happened on LCT N-terminal . Point mutants in 10 kinds of LCT sequences all led to amino-acid change. The LCT kinds were different in different wheat accessions. Four LCT kinds were found in Chadianhong and only one in Bainong 3217 and Sumai 3. LCT3-1 exists in six wheat accessions.