Genetic structure and differentiation of three Penaeus semisulcatus stocks from the coastal waters of Xiamen and Shantou,China

采用聚丙烯酰氨凝胶电泳对2002年10月采集的厦门(XM02)和汕头(ST)沿岸短沟对虾野生群体和2003年8月采集的厦门沿岸短沟对虾野生群体(XM03)进行群体遗传结构及其分化的研究。共检测了EST、ACP、ALP、MDH、ME、SOD、POD、ADH和LDH等9种酶共23个基因座位。结果表明:3个群体平均每位点等位基因有效数目(Ae)为1·207-1·244,多态位点百分数(P0·95)为39·13%-43·48%,群体平均观察杂合度(H0)为0·1231-0·1494,期望杂合度(He)为0·132-0·1443;XM02、XM03和ST的遗传偏离指数(d)分别为0·041、-0·045、0·181,表明群体内的近交衰退不明显,遗传变异水平较高,种质资源尚好。群体之间的遗传距离(D)为0·0010-0·0064,基因流(Nm)为18·98-26·57,表明厦门和汕头短沟对虾应属同一群体,推测台湾海峡中部较深水域或东侧的较高温度水域为其越冬和繁殖的场所[动物学报52(2):349-354,2006]。Three natural stocks of Penaeus semisulcatus(XM02, XM03 and ST ) were sampled between Oct. 2002 and Sep. 2003 from the coastal waters of Xiamen and Shantou and analyzed electrophoretically for genetic structure and genetic differentiation. 9 isozymes (EST,ACP,ALP,MDH,ME,SOD,POD,ADH and LDH) coded by 23 loci were examined. The mean effective number of alleles per locus (Ae) of three stocks ranged from 1.207 to 1.244, and the percentage of polymorphic loci (P 0.95) ranged from 39.13% to 43.48%. The expected value of heterozygosity (He) and observed value of heterozygosity (Ho)were 0.1231-0.1494 and 0.132-0.1443, respectively. We concluded that these stocks maintain relatively high genetic variability. The genetic departure index (d value) of XM02,XM03 and ST were 0.041,-0.045 and 0.181 respectively. The genetic distance (D) and genetic similarity (I) among stocks were 0.0010-0.0064, 0.9936-0.999, respectively, gene flow (Nm) was 18.98-26.57. These results revealed no significant differentiation among the three stocks, they should belong to one population. We purpose that the deeper or warmer waters in the middle of Taiwan strait might be its overwintering and maturation place.国家自然科学基金资助(No·30471322)~