【作者】 李朝霞；

【导师】 王清印； 李健；

【作者基本信息】 中国海洋大学 ， 海洋生物学， 2006， 博士

【摘要】 1.“黄海1号”是经国家水产原良种审定委员会审定的中国对虾养殖新品种,目前已有其遗传结构变异方面的调查,但对其体型特征尚未作系统研究。本试验对中国对虾“黄海1号”人工选育群体和野生群体的样品进行了11项形态性状的测定,通过方差分析和两种多元统计分析方法,比较两个群体的外部形态特征。方差分析和t检验结果表明,两个群体在部分形态特征上表现出明显差异,主要反映在选育对虾的腹节3、5及腹节6长度增加,但头胸甲及腹节1的宽度降低。主成分分析构建了4个主成分,其累积贡献率分别为:主成分1为18.14%,主成分2为15.09%,主成分3为11.09%,主成分4为9.53%,累积贡献率为53.85%。结果表明,两个群体在横向体型因子方面差异最明显,结果与显著性检验的结论基本一致。判别分析显示,两个对虾群体的形态差异显著（P<0.000 1）。建立了两个群体的判别函数,其判别准确率P₁为62%～75%,P₂为55.4%～79.8%,综合判别率为70.67%,可以认为逐步判别对于中国对虾不同群体的初步鉴定是可行的。选育群体的判别准确率（75%）相对较高,从而从形态学方面体现了选择育种的效果。2.利用7对AFLP引物组合检测了中国对虾野生群体及连续四代选育群体基因组DNA的遗传结构,根据AFLP分析结果计算了选育世代群体间的遗传相似系数和遗传距离。结果表明,AFLP标记表现出较高的多态检测效率,7对引物共产生500余条带,平均每对引物组合检测到33.7个多态性标记,由shannon信息指数反映的遗传多样性为0.1366～0.1608,非常适合于遗传多样性分析。结果显示,随着选育世代的增加,选育群体的遗传多样性呈现下降趋势,但随着选育时间的延长,群体之间的分化逐渐降低,群体的遗传结构开始趋于稳定。选育群体经过了长时间针对生长速度的人工选择,等位基因频率开始发生变化,表现在稀有位点丢失,低频位点数目降低,并且部分位点的基因频率的变化方向与选育时间一更多还原

【Abstract】 1.The selected fast-growth population of shrimp Fenneropenaeus chinensis had been examined and approved by China National Aquaculture Variety Approval Committee as a new variety for aquaculture and named as“Huanghai No.1”in 2004. Researches have been carried out to study the variance of genetic diversity of the new variety, however, no elaborate analysis of morphologic characters of the new variety was conducted. This paper presents results of studies on the comparison of morphologic characters in the wild and selected“Huanghai No.1”populations of shrimp Fenneropenaeus chinensis base on 11 morphological characters using the method of statistics, including ANOVA analysis and two types of multivariation analyses. ANOVA analysis and t-test indicated that different populations showed some morphological variations, which reflected by the longer length of the 3st, 5st and the 6st somites and the narrower width of carapace and the first somite of selected population compared with that of wild population. In the principal component analysis, four principal components were constructed, the contributory rates of the first, second, third and fourth principal component were 18.14%, 15.09%, 11.09%, and 9.53%, respectively. The cumulative contribution rate was 53.85%. The results revealed that the differences in transverse factor were most significant, which were in accordance with the conclusions of t-test. The results of discriminant analysis revealed that there were significant differences between the two populations （P<0.0001）. The identification accuracy were 62%-75% （P₁） and 55.4%- 79.8% （P₂）, respectively. The total discriminant更多还原