异育银鲫准回交世代经济性状优势的遗传基础研究

Genetic Basis of the Economic Trait Superiority of the Para-Hybrids of Allogynogenetic Silver Crucian Carp and Red Common Carp Determined by RAPD Analysis

用RAPD技术分析了方正银鲫、异育银鲫、异育银鲫准回交世代和兴国红鲤 4个群体的遗传相似性。方正银鲫、异育银鲫和异育银鲫准回交世代多态位点数接近 ,且显著低于兴国红鲤 ;异育银鲫准回交世代存在特异带或特有带 ;方正银鲫与异育银鲫间的遗传相似性高于它与异育银鲫准回交世代间的遗传相似性 ,而兴国红鲤与异育银鲫间的相似性低于其与异育银鲫准回交世代间的遗传相似性。结果表明 :三倍体群体遗传多样性低于正常二倍体 ;异育银鲫准回交世代存在遗传重组 ;随着兴国红鲤精子刺激次数增加 ,后代遗传背景与方正银鲫差异越来越大 ,而与兴国红鲤越来越相似。精子刺激三倍体卵发育 ,也能将一些遗传物质整合进卵细胞核 ,使后代经济性状呈现一定的优势。

The genetic similarities of silver crucian carp (Carasssius auratus gibelio) (CAG), allogynogenetic silver crucian carp (ASCC), para-hybrids of allogynogenetic silver crucian carp and red common carp (PHAR) and red common carp (Cyprinus carpio) (CC) populations were determined by RAPD analysis. The polymorphic band numbers of CAG, ASCC and PHAR are similar to each other, but lower than that of CC significantly. Some bands are specific for or unique to PHAR. The similarities between CAG and ASCC are higher than those between CAG and PHAR, while the similarity between CC and ASCC is lower than that between CC and PHAR. These findings imply that a diploid population is more diverse than triploid populations; genetic recombination has occurred in the PHAR genome; and PHAR becomes similar to CC gradually with the increase of CC sperm stimulation times. When CC sperm stimulates the development of triploid ova, it may integrate some of its genetic materials into ASCC and PHAR genomes, providing a genetic basis for their economic trait superiorities.