In this study, total 35 microsatellite DNA markers were selected to analyze the genetic structure of 110 individuals in an F2 family which is obtained by directional mating techniques for the selective program on fast growing Portunus trituberculatus. (The F2 family was created by F1 family which was generated by wild populations from Laizhou Bay and Zhoushan Island.) The results showed that total 87 different alleles were found, and the number of alleles was 2 to 4 in each locus, with 2.2 effective alleles on average. The value of mean observed heterozygosity, the value of mean expected heterozygosity and the mean Polymorphism Information Content (PIC) was 0.646 5, 0.513 0 and 0,449 1, respectively. The probability value of chi-square test showed that most of the loci deviated from Hardy-Weinberg equilibrium significantly. The GLM procedure in SAS9.1 was used to analyze the correlation between these 35 microsatellite markers and growth related traits of P. trituberculatus. The growth related traits included full carapace width, body weight, carapace width, carapace length, body height, second obital margin width, meropodit length of the claw, meropodit length of the first peraeopod. Results indicated that Pot08 had a significant impact on full carapace width, body weight, carapace length, body height, second obital margin width; Pot42 had a significant impact on body weight, carapace length, meropodit length of the claw, meropodit length of the first peraeopod; Pot53 had a significant impact on carapace widih and meropodit length of the claw, and had a very significant impact on second obital margin width; Poe57 and PTR30 had a significant impact on meropodit length of the first peraeopod and carapacel length, body weight, respectively; PTR8a had a significant impact on the first peraeopod and carapace length, body height, and had a very significant impact on body weight, second obital margin width, full carapace width and carapace width; PTR131 had a significant impact on body weight, full carapace width and carapacel width. Finally, PTR8a can be used for marker assisted selection which could be used for body weight selection.%选用35个多态性微卫星标记,对三疣梭子蟹人工选育快速生长自交家系F2代(以2008年莱州湾群体雄蟹为父本和海洲湾群体雌蟹为母本交配产生F1代,随机选取F1代后代进行交配产生F2代自交家系)的110个个体进行遗传多样性研究.结果表明:35个位点共检测出87个等位基因,各位点等位基因数为2～4个不等,平均有效等位基因数为2.2个,观测杂合度平均值为0.646 5,期望杂合度平均值0.513 0,多态信息含量平均值0.449 1.经卡方检验,多数位点显著(P＜0.05)或极显著(P＜0.01)偏离Hardy-Weinberg平衡.采用SAS 9.1中的一般线性模型(general linear model,GLM)对微卫星标记与生长相关性状(全甲宽、甲宽、甲长、体高、体质量、第Ⅱ侧齿间距、第Ⅰ步足长节长、大螯长节长)进行连锁分析.结果表明,Pot08位点与体质量、全甲宽、甲长、体高、第Ⅱ侧齿间距显著相关(P＜0.05),Pot42位点与体质量、甲长、大螯长节长、第Ⅰ步足长节长显著相关(P＜0.05),Pot53位点与全甲宽、甲宽、大螯长节长显著相关(P＜0.05),与第Ⅱ侧齿间距极显著相关(P＜0.01),Pot57位点与第Ⅰ步足长节长显著相关(P＜0.05),PTR8a位点与第Ⅰ步足长节长、体高、甲长显著相关(P＜0.05),与体质量、第Ⅱ侧齿间距、全甲宽、甲宽极显著相关(P＜0.01),PTR30位点与体质量和甲长显著相关(P＜0.05),PTR131位点与体质量、全甲宽、甲宽显著相关(P＜0.05).其中,位点PTR8a可作为以体质量为选育目标的首选标记.
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