梨形环棱螺生长性状遗传参数估计
时间:2018-07-20 16:23 来源:毕业论文 作者:毕业论文 点击:次
| 摘要：本次实验研究采用构建全同胞家系，获得了梨形环棱螺60日龄生长性状的遗传学参数，通过估算基础群体的遗传参数，为梨形环棱螺进一步选择育种提供基础依据, 也为其它贝类选择育种提供参考。利用3个群体随机交配获得的F1代69个全同胞家系作为选育基础群体，每个家系随机保留30个个体。幼螺达到60日龄时，测量它们的壳高、壳宽、壳口高、壳口宽、体螺层高、体质量6个生长性状，并利用贝类标签进行个体标记，共标记2070个个体。结果表明，壳高、壳宽、壳口高、壳口宽、体螺层高、体质量这6个性状的遗传力分别为：0.372±0.078，0.389±0.080，0.408±0.081，0.395±0.080，0.443±0.085，0.444±0.086。这6个性状的表型相关和遗传相关的范围为：0.878~0.955和0.848~0.967。梨形环棱螺60日龄生长性状有足够的遗传方差，可以对它们进行遗传改良，预期能够获得较好的遗传进展。这6个性状之间的表型相关和遗传相关均较紧密，可以通过对体质量进行选择，同时改良其它性状。25916 毕业论文关键词：梨形环棱螺；生长性状；遗传力；遗传相关 Genetic evaluation about Growth traits of B.purificata Abstract： The full-sib families were built during the entire experience for the purpose of obtaining the genetic parameters of traits of 60-day-growth B.purificata, as well as estimating the genetic parameters in a basic population so that provide more basis for the further selection and breeding. Besides, it can provide more cases for the selection and breeding of other types of shellfishes. The basic breeding groups were selected from F1, the 69 full-sib families, which were radom generations of 3 populations, and every group retains 30 inpiduals. The shell height,Shellwidth,aperture height,aperture width,body whorl height and body weight should be measured when the larvae grew up to 60-day old marked the inpiduals with labels and 2070 inpiduals were marked. The results showed the heritability of these six traits were 0.372±0.078，0.389±0.080，0.408±0.081，0.395±0.080，0.443±0.085，0.444±0.086 respectively. The phenotypic and genetic correlations of these six traits were 0.878~0.955 and 0.848~0.967.It shows that there are adequate genetic variance in the growth traits of 60-day-old B.purificata. Genetic modifications could be conducted and it would have promising breakthrough.. The phenotypic and genetic correlations of these six traits were both tight, other traits can be modified by selecting the body weights. Key words: B.purificata, growth traits, heritability, genetic correlations 目 录 摘要1 关键词1 Abstract1 Key words1 引言（或绪论）1 1材料与方法 2 1.1亲本选择 3 1.2亲本抽样与个体标记3 1.3实验管理3 1.4数据处理与分析3 2结果与分析4 2.1描述性统计结果4 2.2方差组分析结果4 2.3表型相关与遗传相关分析5 3讨论 5 致谢6 参考文献6 梨形环棱螺生长性状遗传参数估计 引言 梨形环棱螺（B.purificata）隶属于腹足纲，前腮亚纲，田螺科，环棱螺属，是环棱螺属中个体最大的属，又称为螺蛳、豆田螺、石螺[1]该种在全国范围内广泛分布、自然捕捞量和人工养殖量大，用途多可直接食用或者作为特种水产品养殖的饵料[2]，是一种食用价值高、口独特的优质食物，因此，越来越得到科技工作者和养殖者的青睐[3]。梨形环棱螺主要以浮游生物、碎屑、有机物腐殖质为食，可以用作某些特种水产养殖的饵料，在生态系统中同时扮演着消费者和分解者的双重身份，由于其食性的特殊性，所以梨形环棱螺具有一定的净水作用在保护水体生态环境方面起到作用[4-7]。一直以来，国内对梨形环棱螺在育种方面的研究还停留在遗传多样性方面的基础研究，而对于遗传育种方面的研究工作投入力度不足，因此梨形环棱螺的种质还处于野生和半野生的状态，会存在生长速度慢、成体偏小的现象，这是梨形环棱螺养殖业发展的一大障碍。目前，梨形环棱螺养殖业的苗种来源依然靠自繁自育以及捕捞自然群体。所以，需要更多的科研投入来进行相关遗传育种方面的研究，早日解决行业难题[8-10]。 (责任编辑：qin) |