中文摘要：

以模式植物Lotus japonicus基因组为研究对象，首先应用了现有生物信息学软件BLAsT程序对Lotus japonicus的全基因组序列进行了比较分析，鉴定两个序列之间的相似性并将其基因筛选出来；其次结合Blastp的数据结果提供的基因同源信息，和基因在染色体上的位置信息，对其全基因组进行共线性分析确定基因组中由WGD产生的重复基因有2197对，以获得Lotus japonicus多倍化发生的规模高达28．05％；再次在NCBI上初步搜索并获得与共生固氮相关的基因序列有12个同时根据获得的共生固氮相关的基因在四个禾本科物种中进行比较分析，并且对其进行了简单的系统进化分析，发现全基因组倍增可能有利于共生固氮相关的基因家族的扩增。

英文摘要：

This paper takes pattern plant Lotus japonicus genome as the research object, firstly, use of existing bioinformatics software program BLAST Lotus japonicus complete genome sequences were compared analysis,identification of two similarity between sequences and their genetic screening out; secondly, combined with Blastp data the resuits provide homologous gene information, and gene in the chromosome location information, the whole genome collinearity analysis identified in the genome of the duplicated genes have produced by WGD 2197 ,to obtain the Lotus japonicus polyploidy occurs up to the size of 28.05% ;Then in the NCBI on the initial search and access and symbi- otic nitrogen fixation genes related to sequence 12 at the same time is obtained based on symbiotic nitrogen fixation genes involved in four gramineous species for comparative analysis, and has carried on the simple phylogenetic anal- ysis, discovered the gene group multiplication may be beneficial for symbiotic nitrogen fixation genes associated with familial amplification.