泥蚶G2代快速生长家系遗传结构的微卫星分析及其与生长性状的关联

利用微卫星标记对泥蚶(Tegillarca granosa Linnaeus) G2代家系的遗传结构和遗传多样性进行了分析, 并结合家系的表型生长数据, 关联分析筛选可用于育种的候选标记。遗传结构分析表明, 18对引物共检测出59个等位基因, 其中家系F19、F21、F22的平均等位基因数(N_a)分别是2.500、2.722和2.722; 平均观测杂合度(H_o)为0.446、0.510和0.628; 平均期望杂合度(H_e)为0.394、0.433和0.464; 多态信息含量(PIC)分别是0.346、0.379和0.403。标记与生长性状的相关性分析显示, 有3个位点与壳高、壳长、壳宽和总质量显著相关, 其中F19家系的Teg-30的BB基因型与壳高、总质量显著相关, F21家系的Teg-03的BB基因型和Teg-20的BC基因型与壳高、壳长、壳宽和总质量均显著相关, 筛选出的与生长性状相关的标记为开展泥蚶分子标记辅助育种提供了有价值的遗传信息和参考依据。

MICROSATELLITE ANALYSIS OF GENETIC VARIATION IN THE FAST GROWTH FAMILIES OF THE 2nd GENERATION OF TEGILLARCA GRANOSA AND CORRELATION WITH GROWTH TRAITS

In this study, microsatellite markers were used to assess the genetic structure and genetic diversity of the second generation of Tegillarca granosa. In addition, the correlation of these markers with growth-related traits was assessed to explore their potential use for marker-assisted breeding. Genome-wide identification and structural analysis herein led to detect 59 alleles through 18 pairs of primers. Among these, the average values of alleles (N_a) in the families of F19, F21, and F22 were 2.500, 2.722, and 2.722, respectively. The average observed heterozygosity (H_o) was 0.446, 0.510, and 0.628; the average expected heterozygosity (H_e) was 0.394, 0.433, and 0.464, respectively. In addition, the corresponding values of polymorphism information content (PIC) were 0.346, 0.379, and 0.403, respectively. Correlation analyses of these polymorphic markers and growth traits revealed significant association of three loci with shell height, shell length, shell width, and total weight. Specifically, genotype BB of Teg-30 in F19 was remarkably associated with shell height and total weight, while genotype BB of Teg-03 and genotype BC of Teg-20 in F21 showed a significant correlation with the shell height, shell length, shell width, and total weight. As a result, the growth-related markers, identified in the present study, may provide precious genetic information and novel insights for molecular marker-assisted breeding of T. granosa.