Estimates of genetic parameters of growth-related traits in Crassostrea gigas ‘Haida No. 1’

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 长牡蛎‘海大1号’生长性状的遗传参数评估 DOI: 作者: 作者单位: 中国海洋大学 海水养殖教育部重点实验室, 山东 青岛 266003 作者简介: 张景晓(1990-),男,博士研究生,从事贝类遗传育种研究.E-mail:jingxiao2000@163.com 通讯作者: 中图分类号: S917 基金项目: 国家自然科学基金项目（31772843）；青岛市产业培育计划项目（17-3-3-64-nsh）；山东省科技发展计划项目（2016ZDJ-S06A06）. Estimates of genetic parameters of growth-related traits in Crassostrea gigas ‘Haida No. 1’ Author: Affiliation: Key Laboratory of Mariculture, Ministry of Education;Ocean University of China, Qingdao 266003, China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:分别以长牡蛎（）‘海大1号’第8代和第9代选育群体中的个体为亲本，采用巢式设计的交配方法，于2016年和2017年分别获得41个和38个全同胞家系。根据各家系长牡蛎330日龄的壳高、壳长、壳宽和体重等表型参数，通过建立多性状动物模型，利用ASReml软件中的限制性极大似然法估算各表型变量的方差组分，对‘海大1号’连续两代选育群体生长性状的遗传参数进行评估。结果表明，两个选育世代的‘海大1号’生长性状均具有较高的变异水平，变异系数为20.74%~55.14%，各生长性状仍具有遗传改良潜力。‘海大1号’各生长性状间的表型相关均为正相关，相关系数大小存在差异。3个壳型性状与体重的遗传相关均为正相关，且处于较高水平（0.40~0.66）。除壳宽性状的遗传力较低外，壳高、壳长与体重的遗传力在0.16~0.37，均属中高等遗传力水平，表明‘海大1号’经过多代选育后，生长性状仍具有较大的加性遗传效应，可根据个体表型值大小，继续通过群体选育获得遗传进展。研究结果为长牡蛎‘海大1号’制种方案的制订和保种工作提供了参考依据。 Abstract:The Pacific oyster , naturally distributed in the Pacific Coast of Asia, has become a global aquaculture species owing to its high fecundity and strong environmental adaptability. It is also the most highly produced mollusk species worldwide, and China is the top oyster-producing country. Although China is the highest producer of oysters with a long history of oyster aquaculture, there are no well-documented cases of selective breeding. To genetically improve the productivity traits of , we initiated a selective breeding program in 2007, concentrating on the establishment of selected strains by mass selection with fast growth rate. After eight generations of selection, significant genetic gains in growth rate were observed in the selected strains. In 2014, the fast-growing strain of ‘Haida No.1’ was established. However, the genetic parameters of growth-related traits in Haida No.1 are still undetermined. As a result of successive selection in closed population, genetic parameters varied between different generations of selected strains. The estimates of heritability and genetic correlation for growth-related traits in Haida No.1, which experienced numerous generations of selection, is of great benefit to long-term breeding program, contributing to the evaluation of increased genetic gains in future generations. In the present study, genetic parameters were estimated for growth-related traits in Haida No.1 after eight and nine generations of selection. A total of 41 and 28 full-sib families were obtained by a nested mating design (1 sires×3 dams) consisting of 60 and 40 broodstocks, which were obtained from the eighth-and ninth-generation selected strains of Haida No.1 in 2015 and 2016, respectively. The shell height, shell length, shell width, and body weight of 2,070 progeny representing 69 full-sib families were recorded at the age of 330 d. The variance components and genetic parameters were obtained from multi-trait animal models using ASReml 3.0 in the R Programming Language. The growth-related traits of Haida No. 1 had a high value of coefficient of variation, which showed a potential for successive selective breeding. The phenotypic correlations between the growth-related traits were positive and varied among different traits. The genetic correlation between body weight and shell shape-related traits (shell height, width, and length) was positive, ranging from 0.40 to 0.66. The heritability estimates of shell height, shell length, and body weight ranged from 0.16 to 0.37, belonging to moderate and high levels of heritability. These results suggest that the effects of successive mass selection on the genetic parameters of growth-related traits in Haida No. 1 were negligible. The high genetic diversity and stable genetic structure of selected strains of Haida No. 1 might be responsible for the high estimates of growth-related trait heritability. The results provide important information for future breeding programs of ‘Haida No. 1’. 参考文献 相似文献 引证文献