翘嘴鳜选育群体的生长和遗传特征分析

以湖南和江苏的野生翘嘴鳜(Siniperca chuatsi)为基础群体选育了6个群体,包括4个家系选育群体和F_1、F_2两个群体选育群体。对4个家系选育群体的生长特性进行了分析,并利用微卫星标记技术对6个翘嘴鳜选育群体的遗传多样性进行了检测。分析结果表明,翘嘴鳜纯种家系的生长速度显著快于不同地理种群的杂交系,杂交系未表现出生长的杂种优势,家系群体的杂合性与生长性能不对应。4个家系选育群体的特有等位基因数量比两个群体选育群体高出约29.33%,表明不同地理种群翘嘴鳜家系的建立可以丰富翘嘴鳜选育群体的遗传多样性水平。翘嘴鳜选育群体间遗传分化显著(F_(st)=0.4388),两个群体选育群体与4个家系选育群体间的遗传距离较远,表明将群体选育的个体与家系选育的个体进行杂交育种有可能获得杂种优势。筛选到G14437特有等位基因可作为江苏翘嘴鳜家系(JCJC)的群体特异性分子标记;G5_(530)等位基因可作为湖南和江苏翘嘴鳜杂交系与翘嘴鳜基础群体和其他选育群体区分的特异性分子标记。

Analysis of growth and genetic characteristics of the breeding populations of Siniperca chuatsi

Based on the wild base-populations sampled from Hunan and Jiangsu provinces, six breeding popula-tions ofSiniperca chuatsi, including four pedigree-bred and two population-bred populations, were cultured. The growth properties of four pedigree-bred populations were studied and the genetic characteristics of all six breeding populations were analyzed with seven microsatellite DNA markers. The growth speed of the pure-bred families were significantly higher than geographic hybrid families, but there was no direct relationship between the growth rates and heterozygosities. The number of private alleles of the pedigree-bred populations was about 29.33% more than that of the two population-bred populations. This means that the establishment ofS. chuatsi family with dif-ferent geographic populations might raise the level of genetic diversity. The genetic differentiation within breeding populations was significant (Fst=0.4388). The relative farther genetic distance between the pure-bred populations and the pedigree-bred populations revealed that the hybridization between them might obtain some offsprings which exhibited heterosis. Private allele G14437 could be used as the specific molecular markers for JCJC popula-tion, while G5530 used to distinguish the geographic hybrid populations (HCJC and JCHC) from other breeding populations.