墨西哥湾扇贝和扇贝“渤海红”及其杂交子代的遗传分析

Genetic Analysis of Argopecten irradians concentricus,“Bohai Red”and Their Hybrids

利用SSR(Simple Sequence Repeats)分子标记技术,对扇贝“渤海红”、墨西哥湾扇贝(Argopecten irradians concentricus)及其杂交子代3个群体共90个个体的遗传多样性进行分析。结果显示,8个SSR位点共扩增出67个等位基因,各位点等位基因数范围为4~14个,平均等位基因数为8.5个。扇贝“渤海红”有效等位基因数(Ne)、平均观测杂合度(Ho)和多态信息含量(PIC)最高,分别为2.3947、0.504和0.462;3个群体的遗传分化指数(Fst)、基因流(Nm)和固定系数(Fis)分别为0.1398、1.5387和0.3698。对亲代与杂交子代间的遗传分化分析表明,杂交子代与扇贝“渤海红”的遗传距离最小(0.1188),遗传相似度最大(0.888),杂交子代的遗传结构更偏向亲本扇贝“渤海红”。研究结果可为扇贝“渤海红”和墨西哥湾扇贝群体种质资源评估和杂交新品种的选育提供理论参考。

Hybridization between the‘Bohai Red’and Argopecten irradians concentricus was conducted.The hybrids exhibited heterosis in terms of survival rate,growth rate,and heat tolerance,demonstrating substantial potential to replace A.irradians concentricus.To ensure the efficient use of these hybrids,we need to understand the genetic structure of the hybrids and their parents.Microsatellites are widely used to assess the genetic diversity of aquaculture species and to construct a quantitative trait locus due to their characteristics such as abundant polymorphism,rich information,and high codominance and conservation.In this research,the genetic diversity of 90 individuals in 3 populations of A.irradians concentricus,‘Bohai Red’,and their hybrids was analyzed using 8 pairs of microsatellite primers.A total of 67 alleles were amplified,and 4~14 alleles at each locus were generated,with a mean allele number of 8.5.Effective allele number,expected heterozygosity,and polymorphic content were the highest in‘Bohai Red’(2.3947,0.504,and 0.462,respectively).The genetic differentiation index,gene flow,and fixed coefficient were 0.1398,1.5387,and 0.3698,respectively.Between the hybrids and‘Bohai Red’,the genetic distance was the smallest(0.1188)and the genetic similarity was the highest(0.888),suggesting their similar genetic structures.These findings provide a reference for the genetic analyses of‘Bohai Red’and A.irradians concentricus as well as for the breeding of new varieties.