不同野生软枣猕猴桃ITS序列分析及遗传多样性探究

ITS Sequence Analysis and Genetic Diversity Research of Different Wild Actinidiaarguta

野生软枣猕猴桃(Actinidiaarguta)在黑龙江地区分布广泛。为了明确野生软枣猕猴桃的亲缘关系,本研究通过ITS基因序列比对分析,对黑龙江4个地区分布的11份野生软枣猕猴桃样品进行遗传多样性研究,结果表明:(1)得到的11份软枣猕猴桃ITS1-5.8S-ITS2序列长度为560~654bp,共有122个可变位点,ITS2序列的可变位点远多于ITS1的可变位点,5.8S序列存在少量变异情况。(2)11份样本遗传距离在0~0.031之间,总体平均遗传距离为0.010,样本1-8与1-4、1-7、1-10、1-13遗传距离最大,为0.031,样本1-1与1-2、1-5,以及样本1-4与1-7、1-10及1-13的遗传距离最小为0。(3)11份样本采集地与ITS序列构建的系统发育分支存在一定的相关性,牡丹江地区的6个样本聚类为遗传距离很近的2个小支,双鸭山地区的样本独立聚成一小支,哈尔滨亚布力地区的样本独立聚成一大支,说明地理位置的远近可以为遗传变异提供变异积累;同时也存在不同地区聚类为一支的情况,哈尔滨方正地区的样本1-10与佳木斯桦南地区的样本1-4聚类为同一小支,说明软枣猕猴桃的系统发育较为复杂,存在地理位置相对较远而亲缘关系较近的情况。本研究为软枣猕猴桃资源保护及品种选育工作提供一定的理论基础。

Wild Actinidia arguta are widely distributed in Heilongjiang region. In order to clarify the relationship of wild Actinidia arguta, 11 samples of wild Actinidia arguta distributed in four regions of Heilongjiang are studied for genetic diversity through ITS sequence analysis. The results show that:(1) The ITS1-5.8S-ITS2 sequence length of Actinidia arguta is 560 to 654 bp, a total of 122 variable sites, ITS2 sequence variable sites are far more than the ITS1 variable sites, there is a small variation in the 5.8S sequence.(2) The genetic distance of 11 samples is between 0 and 0.031, the overall average genetic distance is 0.010, sample 1-8 has the largest genetic distance with 1-4, 1-7, 1-10, 1-13, which is 0.031. Sample 1-1 and 1-2, 1-5, as well as sample 1-4 and 1-7, 1-10 and1-13 have the smallest genetic distance, which is 0.(3) The geographical location of 11 samples was correlated with phylogenetic clustering, the six samples in Mudanjiang region are clustered into two small branches with very close genetic distance, the sample in Shuangyashan region is clustered into a small branch independently, and the sample from Harbin Yabuli region is clustered into a large branch independently. It indicates that the distance of geographical location could provide genetic variation accumulation. At the same time, the samples from different regions are occasionally clustered into the same branch. Sample 1-10 in Harbin Fangzheng region and sample 1-4from Jiamusi Huanan region are clustered in the same small branch, indicating that the system development of Actinidia arguta is more complex, the geographical location is far away but the genetic relationship is close. This study provides a theoretical basis for resource protection and breeding of Actinidia arguta.