鲤和牙鲆的两种雌核发育子代的基因型分析

The genotyping of progenies from two kinds gynogenetic techniques of two fish species

研究调查了鲤和牙鲆经两种雌核发育操作获得的子代的基因型纯合情况。结果显示,多数子代在母本杂合基因座上的纯合速率并不快,如鲤抑制第一次卵裂的44尾子代平均纯合化程度为30.2%,纯合化程度最高的个体为53.3%,纯合化程度最低的仅有13.3%,没有得到纯合个体;牙鲆抑制第一次卵裂22个子代中有3个纯合个体;而抑制第二极体的牙鲆4个家系中纯合化最高的个体是C家系的第18号子代为56%,平均纯合度为19%,14个子代的纯合化速率为零。结合鲤抑制第二极体和牙鲆抑制第一次卵裂的实验结果对两种雌核发育产生的纯化作用进行了分析和评价;并针对育种过程中的雌核发育技术进行了讨论。

Some fishes have the genetic characteristic of gynogenesis. Copying natural gynogenesity of fish and making use of the superiority of fertilization and hatching out of body for fishes, two artificial gynogenetic techniques have been developed 40 years ago, meanwhile these two gynogenetic techniques were used in fish breeding researches. In this paper, we investigated the increasing of homozygosity of progenies from the inhibition of first mitosis in common carp（Cyprinus carpio L. ）, and also investigated the homozygosity of progenies from the inhibition of the second meiotic division in Chinese flounder （Paralichthys olivaceus）. The results showed that the increasing of homozygosity of progenies is not quick in most heterozygous loci, for example, from 44 progenies of mitogynogenesis of common carp, mean homozygosity is 30.2% and the highest homozygosity is 53.3%,the lowest homozygosity is 13.3%, none of homozygous progenies were found; 19 progenies were gotten from mitogynogenesis of Chinese flounder, and only 3 are homozygous; 4 families of progenies of the meiogynogenesis of Chinese flounder, the mean homozygosity is 19%, the highest homozygosity is 56%, the 14 progenies have 0 homozygosity. Meanwhile, the function of two kind of gynogenetic technoques in fish breeding was discussed recombinant among our other results including the progenies from carp homozygosity and flounder homozygosity. This paper also discusses and compares the results on similar experiments from other investigator.