基于ITS序列的新疆野苹果系统发育分析

Phylogenetic analysis of Malus sieversii based on the nrDNA ITS region

利用PCR和DNA测序技术,获取3个居群新疆野苹果的ITS序列,并结合GenBank里已有的中亚地区的新疆野苹果、欧洲苹果、栽培苹果和东方苹果的ITS序列进行比对分析,利用MEGA5.0软件选择"Krima2-Paramenter"核酸距离模式获得遗传距离矩阵,用邻接法(neighbor-joining,NJ)进行独立的系统发育分析,结果显示,所有供试材料的ITS1的长度为209～224 bp,GC含量为66.1%～66.9%,ITS2的长度为201～290 bp,GC含量为65%～71.5%,遗传距离为0～0.21,进化树分为三支。新疆野苹果的遗传多样性与地理分布有正相关关系,不同居群之间存在基因交流。

The internal transcribed spacer of ribosomal DNA （rDNA-ITS） of Malus sieversii collected from 3 population was ampli- fied with PCR and then sequenced, aligning with Malus sieversii from Central Asia was compared with that of Malus sylvestris, Malus domestica and Malus oriental retrieved from GenBank. The genetic distance from Krima 2-Param enter mode was calculated and the NJ phylogenetic tree was constructed using the software MEGA 5.0. The results showed that, the length of ITSI sequences was 209 -224 bp, and the average GC contents of the sequence were 66. 1% -66.9%. ITS2 was 201 -290 bp, and the average GC contents of the sequence were 65% -71.5%. Genetic distance is 0 -0. 21, and the NJ phylogenetic tree showed that all materials could be classified into three groups.