基于线粒体D-loop区和Cyt b基因分析广西禾花鲤三个群体遗传结构

研究基于线粒体D-loop区和Cyt b基因部分序列, 分析了广西全州、融水、环江三地禾花鲤(Cyprinus carpio)的遗传结构。在3个群体中共鉴定到19种D-loop与Cyt b序列的组合单倍型, 总的单倍型多样性(H_d)和核苷酸多样性(π)分别为0.916±0.010和0.008±0.004, 禾花鲤线粒体DNA具有单倍型多样性高和核苷酸多样性低的特点。环江群体单倍型多样性最低, 但是核苷酸多样性却最高, 反映了环江群体存在最明显的谱系混杂。分子方差分析(AMOVA)显示遗传变异主要来源于群体内部(71.54%), 禾花鲤三个群体间有显著的遗传分化(F_st=0.285; P<0.01)。系统发育分析表明, 多数样本的线粒体单倍型属于华南鲤(C. carpio rubrefusus)类型, 同时三地禾花鲤中均检测到一定频率的西鲤(C. carpio carpio)或远东鲤(C. carpio haematopterus)类型的线粒体单倍型, 提示禾花鲤可能受到鲤养殖品种的杂交渐渗。研究初步揭示了广西禾花鲤的种质资源现状, 为禾花鲤这一地方特色“稻鱼共作”品种的选育和苗种管理提供了必要的依据。

GENETIC STRUCTURE OF THREE POPULATIONS OF RICE FLOWER CARP(CYPRINUS CARPIO)IN GUANGXI ZHUANG AUTONOMOUS REGION BASED ON MITOCHONDRIAL D-LOOP REGION AND CYT B GENE

Rice flower carp is a traditional species in the“Rice-fish co-culture system”in Guangxi Zhuang Autonomous Region,China.Based on partial sequences of D-loop region and Cyt b gene of mitochondrial DNA,the genetic structure of rice flower carp in the Quanzhou(QZ),Rongshui(RS)and Huanjiang(HJ)were studied.A total of nineteen concatenated haplotypes of D-loop and Cyt b sequences were identified in three populations.Haplotype diversity(Hd)and nucleotide diversity(π)were 0.916±0.010 and 0.008±0.004,respectively.Mitochondrial diversities of rice flower carp were characterized by high haplotype diversity and low nucleotide diversity.Among the three populations,the haplotype diversity of HJ was the lowest,but its nucleotide diversity was the highest,which reflects the significant mixture of divergent lineage in HJ population.There was significant genetic differentiation among the three populations(Fst=0.285;P<0.01).Molecular analysis of variance(AMOVA)showed that the genetic variation was mainly within the population(71.54%).Phylogenetic analysis showed that most of the mitochondrial haplotypes in the samples belonged to the haplogroup of C.carpio rubrefusus,and certain frequencies of the mitochondrial haplotypes of C.carpio carpio or C.carpio haematopterus were also detected.Thus,it indicates that the introgressions from cultured common carp breeds may exist.Our study preliminarily revealed the current situation of germplasm resources of rice flower carp in Guangxi,and provided necessary basis for breeding and seedling management of rice flower carp.