马氏珠母贝金黄壳色系F_3和基础群体遗传结构比较

Genetic structure of the third generation yellow colored line and base stock of pearl oyster Pinctada martensii as revealed by SSR marker system

2003年4月,从广东湛江流沙港养殖群体选取金黄壳色个体为亲本建立育种基础群体,2004-2007年期间,按照壳色性状对基础群体进行连续3代选择建立选系F3。2009年5月,利用10对微卫星引物分析了金黄壳色系F3和基础群体的遗传结构。结果表明：在10个位点中共检测出40个等位基因,每个位点产生的等位基因数2~6个,平均每个位点产生4个等位基因;金黄壳色系F3和基础群体的平均有效等位基因数分别为2.286 2和2.264 6,平均表观杂合度分别为0.411 9和0.440 3,平均期望杂合度分别为0.533 3和0.546 4,平均多态信息含量分别为0.472 2和0.465 5;两个群体的平均遗传分化系数为0.038 9,属于轻度偏中度分化水平。本研究说明了,经过3代连续选择后选系具有较高的遗传多样性。

In April of 2003,the base stock was developed by selecting yellow colored individuals as parental breeders in the Liushagang stocks,Zhanjiang,Guangdong Province,China.During the period of 2004-2007,a successive three generation selection for yellow shell color in the base stock were carried out to produce the third generation yellow colored line.In May of 2009,genetic structures of the third generation yellow colored line and base stock were evaluated by ten SSR primers.A total of 40 alleles were detected in the 10 loci assayed.All the loci were polymorphic and the number of alleles ranged from 2 to 6,with a mean number of 4 alleles per locus.The average effective allele numbers,observed heterozygosity,expected heterozygosit and PIC values of the third generation yellow colored line and base stock were 2.286 2 and 2.264 6,0.411 9 and 0.440 3,0.533 3 and 0.546 4,0.472 2 and 0.465 5,respectively.The genetic differentiation index was 0.0389.The results indicated that there existed a high level of genetic variation in the third generation yellow colored line after three generation selection for yellow shell color.