凡纳滨对虾选育群体生长、存活和耐低溶氧性状遗传参数的估计

发布时间：2018-06-01 23:01

本文选题：凡纳滨对虾 + 生长性状　；参考：《广东海洋大学》2016年硕士论文

【摘要】：凡纳滨对虾(Litopenaeus vannmei),因其具有生长快、适应性强、适合高密度养殖等特点,已成为我国对虾养殖业重要的养殖品种之一,目前国内凡纳滨对虾苗种已出现种质衰退现象,严重影响了我国对虾养殖业的可持续发展,因此针对凡纳滨对虾开展选择育种是十分重要的。本研究为培育生长速度快、抗逆性强的凡纳滨对虾新品种,针对以下几个方面开展了研究。通过群体间杂交构建不同的自交和杂交群体G1代,比较分析了其在不同密度下生长和成活的表现情况;选取生长和耐低溶氧性状优良的自交和杂交群体作为亲本建立选育群体G2代,估计G2代生长和耐低溶氧性状的遗传参数,并对其遗传进展进行预测;通过综合育种值从G2代中筛选出表现良好的家系作为亲本,大规模建立家系,估计G3代的生长、存活和耐低溶氧性状的遗传参数,并对生长和耐低溶氧性状的遗传进展进行评估;从G2代中筛选出4个生长性状或耐低溶氧性状表现良好的家系作为亲本,通过不完全双列杂交建立不同的杂交组合,比较分析了子代生长和耐低溶氧性状的差异性。具体研究如下:1、不同养殖密度下凡纳滨对虾选育群体G1代生长和成活性状的比较以8个凡纳滨对虾养殖群体作为亲本,构建8个子代群体;在80尾·m-2、200尾·m-2和400尾·m-2养殖密度下研究各群体生长、成活性状。结果表明,养殖密度对各群体生长、成活性状有显著影响(P0.05),随着养殖密度增加,生长、成活指标呈下降趋势。80尾·m-2养殖密度的生长比速、成活率的范围及平均值分别为(8.29~10.38,9.29±2.14)和(66.7~96.7,82.9±10.5)%,显著高于200尾·m-2、400尾·m-2的生长、成活指标(P0.05)。3个养殖密度下各群体间生长、成活性状有显著差异(P0.05)。SIS♀×SIS♂生长优势明显,生长比速较群体均值提高10.4%~17.9%;HD♀×YH♂成活优势明显,成活率较群体均值提高9.3%~13.7%;YH♀×ZX♂和YH♀×K♂生长比速、成活率均高于群体均值,表现出生长快成活率高双重优良性状。2、凡纳滨对虾选育群体G2代生长和耐低溶氧性状遗传参数估计及遗传进展的预估选择来自40个家系的3200尾凡纳滨对虾个体分别于8和13周龄时进行为期96h的耐低溶氧试验,测定其生长性状和耐低溶氧性状。利用线性动物模型针对凡纳滨对虾不同日龄生长和耐低溶氧性状的方差组分和遗传参数进行估计。结果显示,凡纳滨对虾生长性状和耐低溶氧性状的遗传力均表现为低中等遗传力水平,分别为0.11~0.23和0.07~0.15。同一时期不同生长性状间的遗传相关为0.84~0.95,表现为高度线性正相关(P0.05),而生长性状和耐低溶氧性状间遗传相关为0.24~0.29,表现为低度线性正相关。相同性状在不同时期的遗传相关较低(0.18~0.29),表明在对虾生长阶段早期对重要经济性状进行选育可能达不到较好的选育效果。体长、体质量和耐低溶氧性状的预测遗传获得为5.0~6.5%、18.2~23.5%、7.6~15.7%,预示利用家系选育对凡纳滨对虾进行遗传改良可取得良好的育种成效。3、凡纳滨对虾选育群体g3代生长和耐低溶氧性状的遗传参数估计和遗传进展的评估选择来自75个家系的6000尾凡纳滨对虾个体进行为期96h的耐低溶氧试验,测定其生长性状和耐低溶氧性状。利用线性动物模型估计了凡纳滨对虾收获时期生长和耐低溶氧性状的方差组分和遗传参数。结果显示,凡纳滨对虾收获体长和收获体质量的遗传力分别为0.35±0.11和0.48±0.15,表现为中高遗传力水平,并且统计检验显著(p0.05)。收获体长和收获体质量间的表型相关和遗传相关分别为0.89和0.95,表现为高度线性正相关(p0.05)。凡纳滨对虾耐低溶氧性状的遗传力为0.07±0.03,表现为低遗传力水平。生长性状和耐低溶氧性状间的表型相关和遗传相关分别为0.11~0.13和0.14~0.18,表现为低度线性正相关(p0.05)。体质量的选择反应和遗传获得分别为1.13±0.31g和11.07%;耐低溶氧性状的选择反应和遗传获得分别为0.02±0.02%和4.87%,表明利用家系选育对凡纳滨对虾生长性状进行遗传改良能够取得良好的育种成效。4、凡纳滨对虾选育群体g3代生长和耐低溶氧性状的配合力分析14个交配组合的生长情况和低溶氧胁迫的耐受情况均存在显著的差异,表明各交配组合生长和耐低溶氧性状具有较大的改良潜力。杂交后代性状表现情况由父本、母本的一般配合力和交配组合的特殊配合力共同决定,a家系父母本在各生长阶段生长性状和耐低溶氧性状的gca效应值均为正值,分别为0.043~0.403和0.163,表明家系a作为亲本时可将优良的生长和耐低溶氧性状稳定遗传给杂交子代。特殊配合力分析表明,杂交组合ab生长性状sca效应值最大,为生长性状的最优杂交组合;杂交组合ac耐低溶氧性状特殊配合力最大,为耐低溶氧性状的最优杂交组合,可为进一步家系选育提供候选材料。5、凡纳滨对虾选育群体g3代不同生长阶段生长和存活性状的遗传参数估计利用线性动物模型估计了凡纳滨对虾不同生长阶段生长和耐低溶氧性状的方差组分和遗传参数,结果显示,凡纳滨对虾经共同环境养殖30d、60d、90d和120d后,生长性状遗传力为0.24~0.46,表现为中高等遗传力水平;存活性状的遗传力为0.01~0.06,表现为低等遗传力水平,并且统计检验显著(p0.05)。凡纳滨对虾生长性状间的表型相关和遗传相关分别为0.82~0.95和0.91~0.97,表现出高度线性正相关;而生长性状和存活性状间的表型相关和遗传相关表现为负相关,其值为-0.03~-0.05和-0.15~-0.22。每个生长阶段选取生长性状和存活性状育种值排序前50%的家系用于比较和相关性分析,结果显示随着日龄的增长,相邻生长阶段间家系排序相同率越高,育种值相关系数越高,可见生长期越长,性状相关性越大。因此作者认为,凡纳滨对虾家系提前筛选的时期均不能低于共同环境养殖90d前,至于更深入的研究,有待于从遗传动态分析的角度进一步研究。
[Abstract]:Litopenaeus vannmei, which has the characteristics of fast growth, strong adaptability and suitable for high density aquaculture, has become one of the most important breed of shrimp aquaculture in China. At present, the germplasm decline of Penaeus vannamei seedlings has appeared in China, which seriously affects the sustainable development of the shrimp aquaculture industry in China. The selection breeding of prawns is very important. In this study, a new breed of Penaeus vannamei, which has fast growth rate and strong resistance, has been studied in the following aspects. The growth and survival of the G1 generation of different self and hybrid populations were analyzed by interpopulation hybridization. The self crossbred and hybrids resistant to low dissolved oxygen were established as parents for G2 generation, the genetic parameters of G2 generation and low dissolved oxygen tolerance were estimated, and the genetic progress was predicted. Through comprehensive breeding values, the families with good performance were screened from the G2 generation as parents, the family was established on a large scale, and the growth and survival of the G3 generation were estimated. Genetic parameters of low dissolved oxygen Resistant Traits and genetic progress of growth and low dissolved oxygen tolerance were evaluated. 4 growth traits or low dissolved oxygen resistant traits were selected from the G2 generation to establish different hybrid combinations through incomplete diallel hybridization, compared with the difference of progeny growth and low solubility in low dissolved oxygen traits. The specific studies were as follows: 1, the growth and survival characteristics of the G1 generation of Penaeus prawns with different breeding densities were compared with 8 vannamei shrimp culture groups as parents, and 8 sub generation groups were constructed. The growth and survival traits were studied under 80 tail. M-2200 tail. M-2 and 400 tail m-2 breeding density. The growth and survival traits had significant influence (P0.05). With the increase of density, growth and survival index showed a decline in the growth ratio of.80 tail. M-2, the range and average of survival rate were (8.29~10.38,9.29 + 2.14) and (66.7~96.7,82.9 + 10.5)% respectively, which were significantly higher than 200 tail. M-2400 tail. M-2. Survival index (P0.) 05) there was significant difference (P0.05) in the growth of.3 breeding density (P0.05), and the growth rate was obviously higher than that of the group mean, and the growth rate was higher than that of the group mean 10.4%~17.9%, and the survival rate of YH was obviously higher than that of the group mean, and the survival rate was higher than that of the group mean, and the growth rate was higher than that of the group mean, and the survival rate was higher than that of the group average. .2 of high growth rate and high survival rate was shown. The estimation of genetic parameters and genetic progress of G2 generation and low dissolved oxygen tolerance of Penaeus vannamei population from 40 families from 3200 families of Penaeus vannamei from 40 families were tested for low solubility in low dissolved oxygen at 8 and 13 weeks, respectively, to determine their growth traits and low tolerance. The linear animal model was used to estimate the variance components and genetic parameters of different days of growth and low dissolved oxygen tolerance of Penaeus vannamei. The results showed that the heritability of the growth traits and low dissolved oxygen tolerance of Penaeus vannamei was low medium heritability, which was 0.11~0.23 and 0.07~0.15. in the same period, respectively. The genetic correlation between growth traits was 0.84~0.95, showing a highly linear positive correlation (P0.05), while the genetic correlation between growth traits and low dissolved oxygen traits was 0.24~0.29, showing low linear positive correlation. The genetic correlation of the same traits at different periods was lower (0.18~0.29), indicating the selection of important economic traits at the early stage of the prawn growth stage. The prediction heredity of body length, body mass and low dissolved oxygen trait is 5.0~6.5%, 18.2~23.5%, 7.6~15.7%, indicating the good breeding effect of genetic improvement on Penaeus vannamei using family breeding,.3, genetic parameters of G3 generation and low oxygen tolerance in the breeding population of Penaeus vannamei. Estimates and genetic advances were selected from 75 families of 6000 Penaeus vannamei from 75 families to test their growth traits and low solubility in oxygen tolerance. The variance components and genetic parameters of the growth and low dissolved oxygen tolerance of Penaeus vannamei during harvest were estimated by linear animal models. The heritability of long and harvest mass of Penaeus prawns was 0.35 + 0.11 and 0.48 + 0.15 respectively, showing a high heritability level and significant statistical test (P0.05). The phenotypic correlation and genetic correlation between the harvest length and the harvest mass were 0.89 and 0.95, respectively, and showed high linear positive correlation (P0.05). The heritability of the traits was 0.07 + 0.03, showing low heritability. The phenotypic correlation and genetic correlation between growth traits and low dissolved oxygen traits were 0.11~0.13 and 0.14~0.18, respectively, and showed low linear positive correlation (P0.05). The selection reaction and genetic gain of body mass were 1.13 + 0.31g and 11.07%, respectively. And genetic gain was 0.02 + 0.02% and 4.87% respectively, indicating that genetic improvement of the growth traits of Penaeus vannamei can be improved by genetic improvement.4. The growth of the G3 generation and low dissolved oxygen tolerance of Penaeus vannamei was analyzed by the combination of 14 Mating Combinations and the tolerance of low dissolved oxygen stress. There were significant differences, indicating that the growth and tolerance to low oxygen tolerance of the mating combinations had great potential for improvement. The traits of the hybrid offspring were determined by the male parent, the general combining ability of the mother parent and the special mating ability of the mating combination. The GCA effect values of the growth traits and low dissolved oxygen resistance of a family parents were all positive. The value, respectively 0.043~0.403 and 0.163, indicated that the family a could inherit the good growth and low solubility oxygen resistance to the hybrids. The special combination force analysis showed that the SCA effect value of the hybrid AB growth character was the best, it was the best hybrid combination of the growth traits, and the special combination ability of the hybrid combination AC with low dissolved oxygen was the greatest. The optimal hybrid combination resistant to low dissolved oxygen can provide a candidate material.5 for further family breeding. The genetic parameters of the growth and survival traits at different growth stages of the G3 generation of Penaeus vannamei were estimated by linear animal models to estimate the variance components and inheritance of Jie Duansheng length and low dissolved oxygen tolerance of Penaeus vannamei. The results showed that after the common culture of 30d, 60d, 90d and 120d, the heritability of the growth traits of Penaeus vannamei was 0.24~0.46, showing the level of high heritability; the heritability of the survival traits was 0.01~0.06, showing the low heritability level, and the statistical test (P0.05). The phenotypic correlation and remains of the growth traits of Penaeus vannamei. 0.82~0.95 and 0.91~0.97, respectively, showed a highly linear positive correlation, and the phenotype correlation and genetic correlation between the growth traits and the survivable forms were negatively correlated, and the value was for the comparison and correlation analysis of the first 50% families of the first 50% of the growth traits and the survivable breeding values at each growth stage of -0.15~-0.22.. The results showed that with the growth of day age, the higher the same rate of family ranking between adjacent growth stages, the higher the correlation coefficient of breeding value, the longer the growth period, the greater the correlation of characters. Therefore, the authors think that the early screening period of the family of Penaeus vannamei can not be lower than that before 90d in the common environment. As for further research, it needs to be from the remains. The point of view of the dynamic analysis is further studied.
【学位授予单位】：广东海洋大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：S917.4

【参考文献】