中文摘要：

对石刁柏（Asparagus officinalis）品种UC309及TD818的两个反转座子逆转录酶序列进行了PCR扩增并对其在基因组中的异质性进行了分析。结果表明,s101366和s107518两个转座子序列均属于Ty1-copia反转座子,是Ty1-copia反转座酶的部分保守区序列,其长度分别为636和653 bp。对随机获得的两个反转座子测序表明两个反转座子存在一定的异质性,其突变主要是由于发生了碱基置换,其中碱基转换分别占到80.4%和80.0%,T圮C和G圮A转换的比例差异不显著。通过对两个石刁柏品种（TD818和UC309）中获得的序列聚类分析发现,s101366和s107518均未表现出性别间、品种间及近缘种间的保守性,甚至表现出了种内异质性大于种间的异质性特征。这说明了两个反转座子处于高度变异的状态,是产生染色体不稳定的重要因素之一。

英文摘要：

Chromosome rearrangement is probably involved in the early origin of plant sex chromosome,while transposon is one of the important inducing factors of chromosome rearrangement. Two retrotransposons were cloned from Asparagus officinalis according to the result of high throughput sequencing, and the genome heterogenicity of the two retrotransposons was also analyzed. The results showed that two retrotransposon sequences（s101366 and s107518） were all belonged to Ty1-copia retrotransposon,and were partial conserved sequences of the Ty1-copia transposase. The size of the two retrotransposons was636 and 653 bp,respectively. Sequencing of the randomly obtained 111 sequences of the two retrotransposons showed that the two retrotransposons all had certain genome heterogenicity. The mutation event was mainly belonged to base substitution, in which the account of base transition was 80.4% and 80.0% respectively, and the proportion of T圮C and G圮A base transition showed no significant difference. Phylogenetic analysis of the retrotransposon sequences from two asparagus varieties（TD818 and UC309） showed that s101366 and s107518 were presented no conservation between sexes, varieties and relatives,and sometimes,the heterogenicity within species was even larger than that between species. The results illustrated that these two retrotransposons were all in a state of high variation, and were important factors of inducing chromosome instability.