马氏珠母贝生长性状相关QTL在两个群体中的验证

Verification of QTL associated with growth traits in two populations of Pearl oyster Pinctada fucata

对两个通过遗传图谱构建定位的马氏珠母贝(Pinctada ucata)生长性状相关的QTL在两个不同群体中进行验证分析。结果显示:QTL471489在深圳群体中与壳高、壳宽显著相关(P<0.05),其CT基因型个体的壳高、壳宽和体质量显著大于CC基因型,CT为优势基因型;而在杂交群体中该QTL与生长性状关联不显著(P>0.05),但CT基因型的生长性状值仍最大。QTL410206在深圳群体中与生长性状关联不显著(P>0.05),而在杂交群体中该QTL与壳高、壳长、壳宽和体质量显著相关(P<0.05),AA为优势基因型。基于这两个QTL在这2个群体中分别构建二倍型,发现在深圳群体中C1(CTAT)型和杂交群体中D1(CTAA)、D2(TTAA)、D3(CCAT)、D4(TTAT)、D5(CTAA)型对马氏珠母贝的生长最为有利,可作为优选的基因型组合。

Quantitative trait loci（QTL） affecting growth traits have been mapped in genetic map of Pinctada fucata. In this study, two of these QTL were verified in two populations with the different genetic backgrounds. The results showed that the QTL471489 was significantly associated with shell height and shell width in Shenzhen population（ P0.05）, and oysters with genotype CT were bigger than those with the genotype TT in shell height, shell width and body mass, CT was the superior genotype. However, it was not significantly associated with growth traits in cross-population（ P0.05）, and CT was still be the genotype with the maximal average of growth traits. QTL410206 was not significantly associated with growth traits in Shenzhen population（P0.05）, but it was significantly associated with shell height, shell length, shell width and body mass in cross-population（P0.05）, and AA was the superior genotype. Diplotypes were constructed based on the two QTLs, and association analyses revealed that C1（ CTAT） in Shenzhen population and D1（ CTAA）, D2（ TTAA）, D3（ CCAT）, D4（TTAT） and D5（CTAA） in cross-population might be the most advantageous diplotypes for growth traits.