基于微卫星标记的刺参群体遗传结构分析及与经济性状的相关性研究

Population genetic structure and relationship between microsatellite markers and economic traits in sea cucumber

采用微卫星分子标记技术对7个刺参Apostichopus japonicus(Selenka)群体:辽宁葫芦岛养殖群体、山东烟台野生群体、山东莱州养殖群体、大连旅顺底播群体、丹东东港养殖群体、大连广鹿岛底播群体、大连黑石礁野生群体的遗传多样性进行分析,并随机抽取7个群体中的180头刺参进行体长、体宽、体积、体质量和总棘数与17个微卫星标记之间的相关性研究。结果表明:用12个微卫星标记共扩增获得83个等位基因,每个位点的等位基因数为3～12个,长度为102～368 bp。刺参群体位点多样性分析显示,各刺参群体等位基因数为5.083 3～5.416 7,平均值为5.261 9;有效等位基因数为3.205 0～3.701 1,平均值为3.446 8;观测杂合度为0.547 5～0.686 9,平均值为0.614 9;期望杂合度为0.649 1～0.697 1,平均值为0.674 1;多态性信息含量为0.598 9～0.638 6,平均值为0.620 0。对各群体的Hardy-Weinber平衡检测显示,7个刺参群体均存在不同程度的平衡偏离。刺参群体遗传分化与基因流分析显示,刺参群体间遗传分化系数平均值为0.078 2,变异主要来源于群体内;基因流平均值为5.301 9,刺参群体间存在一定程度的基因交流。刺参群体间遗传相似性系数为0.731 8～0.886 0,UPGMA聚类显示,7个群体中山东烟台野生群体单独为一类,其他6个群体聚为一类。刺参微卫星标记与经济性状相关性分析显示,HC312、EAJ07位点与刺参体长、体积、体质量显著相关(P<0.05);IS45、EAJ03、EAJ04位点与刺参体长、体积、体宽、体质显著相关(P<0.05);SJ04位点仅与刺参总棘数显著相关(P<0.05);SJ09位点与刺参体积、体宽、体质量显著相关(P<0.05);SJ18位点仅与刺参体宽显著相关(P<0.05);SJ19位点与刺参体积、体宽、体质量、总棘数显著相关(P<0.05);SP072位点与刺参体积、体质量显著相关(P<0.05)。本研究结果可为刺参群体结构优化、经济性状的QTL定位、养殖和选育提供参考。

Microsatellite marker technique was used to estimate extent of genetic diversity among 7 sea cucumber Apostichopus japonicus （Selenka） populations including farmed Huludao （HLD）in Laoning Province, wild Yantai （SDYS） in Shandong Province, farmed Liazhou （SDYZ） in Shandong Province, ranched Ltishun（LS） in Laoning Province, farmed Dandong（DD） in Laoning Province, ranched Guanglu （GLD） in Laoning Province, and wild Heishijiao（DLYS） in Laoning Province, and the relationship between economic characters of sea cucumbers and microsatellite markers were analyze in 180 individuals sampled from 7 populations. The results showed that 83 allel- ic genes were amplified with 12 mierosatellite markers and the number of alleles ranged from 3 to 12 per locus con- taining 102-368 bp. The locus diversity analysis showed that the alleles were found to be ranged from 5. 083 3 to 5. 416 7 in number in each sea cucumber population with an average of 5. 261 9, effective number of alleles ranged from 3. 205 0 to 3. 701 1 with an average of 3. 446 8 ,observed heterozygosity ranged from 0. 547 5 to 0. 686 9 with an average of 0. 614 9, expected polymorphic information content heterozygosity ranged from 0.649 1 to 0.697 1 with an average of 0. 674 1, and ranged from 0. 598 9 to 0. 638 6 with an average of 0. 620 0. Hardy-Weinber test indicated that there was a certain degree deviation from equilibrium in 7 sea cucumber populations. There was a certain degree of genetic exchange in sea cucumber populations, with genetic differentiation of 0. 078 2, largely de- rived from the variation within populations, and average gene flow of 5. 301 9. Sea cucumber populations showed genetic similarity from 0. 731 8 to 0. 886 0. UPGMA showed that the SDYS population was clustered into one group alone. The relationship between economic characters of the sea cucumber and microsatellite markers revealed that HC312 and EAJ07 were significantly correlated with body length, body volume and body weight（P〈0.05 ）, while IS45, EAJ03 and EAJ04 were significantly related with body length, body volume, body width and body weight（P〈 0.05 ） ;SJ04 had a significant relationship with total tubercle number（P〈0.05） only, while SJ09 was significantly correlated with body volume, body width and body weight（P〈0.05）;SJ18 was significantly correlated only with body width（P〈0.05 ） , while SJ19 was significantly related with body volume, body width, body weight and total tubercle number（P〈0.05）; SP072 was significantly involved in body volume and body weight（P〈0.05）. The findings provide some guidance for sea cucumber cultivation and breeding.