苦荞种质资源表型性状的遗传多样性分析

为了解苦荞产量与农艺性状之间的关系,以26个苦荞种质资源为材料进行主要表型性状与产量的统计分析。结果表明：26个苦荞种质资源存在丰富的遗传变异,不同性状之间变异系数差异较大,变异系数最大的是主茎分枝数,为33.30%,变异系数最小的是生育日数,为6.13%。相关性分析表明,苦荞各性状之间存在不同程度的相关性,且大多数性状与产量呈正相关关系。主成分分析提取了前3个主成分,其累计贡献率达到89.55%。聚类分析将26个苦荞种质资源分为3类,第Ⅰ类综合性状不突出,第Ⅱ类属于高产型,第Ⅲ类属于矮秆型。     

表型可塑性对木本植物树冠结构与发育的影响

作为一组固生生物 ,树木具备一种独特的生存能力来适应在漫长生长过程中发生的环境变化。正是因为这样的原因 ,树木的许多生物学特性 ,如分枝习性与树冠结构 ,代表了树木的生长“蓝图”或基因型与其生长环境及历史的互作关系。遗传因子通过突变 ,染色体重组、基因重复 ,易位与互换等过程形成树木发育成固定的结构。早期形态学家已认识到 ,树木存着大量的形态与发育方面的重复 ,利用这些重复的分化 ,许多热带树种可以被划分成少数几组形态。类似的工作已用在温带树木的结构分析上。但是 ,尽管发展这样的一个分类机制是很容易的 ,然而实际的应用却非常困难 ,这是因为在相同的树木类别内 ,甚至在相同树种内 ,存在着巨大的表型分化。不同的环境或发育过程会使具有相同基因型的树木产生不同的结构 ,由此可见其影响和遗传影响同样复杂环境对树木结构的影响称为表型可塑性。通过缓解自然选择的效应 ,表型可塑性对提高植物适应能力具有重要作用。如果表型可塑性存在遗传变异 ,那么 ,具有不同可塑性的群体会产生进化。表型可塑性亦可用于分析由环境引起的性状相关 ,例如环境能导致性状相关在方向与大小上的变化。基因型与环境互作的结果导致有机体的发育以外遗传的系统的改变 ,产生所谓的异时性生长 (heterochron     

Wild Cherry (Prunus avium L.) for Timber Production: Consequences for Early Growth from Selection of Open-pollinated Single-tree Progenies in Sweden

Prunus avium L. is a fast-growing hardwood tree species that has demonstrated good production on both well-drained forest soils and farm land in southern Sweden. Growth rate and breeding value were tested in 101 open-pollinated single-tree progenies of Swedish origin and five German seed sources. After eight growing seasons and two selective thinnings the mean tree height reached 4.7 m. The mean tree height of the progenies varied between 3.3 and 6.1 m. A total rotation period of 50-60 yrs and a dominant height of 20-22 m can be expected. The results indicated great phenotypic variation within progenies and good possibilities for improving production and stem quality by early selective thinning. In terms of height growth and stem straightness the best Swedish progenies were as good as the tested German seed sources.     

Estimation of genetic parameters of conformation traits in Iranian Thoroughbred horses

The aim of this study was to estimate the genetic parameters of conformation traits in Iranian Thoroughbred race horses. The data set included the conformation records of 607 Thoroughbred horses. In this study, 10 conformation traits were recorded. The effect of sex was significant for length of back line (P < 0.05), withers height (P < 0.05), circumference of front cannon (P < 0.001), and circumference of hind cannon (P < 0.001). The effect of age was significant for all traits (P < 0.01). The genetic parameters were estimated by the restricted maximum likelihood (REML) method using DFREML program. The heritability estimates were for head length 0.39, length of back line 0.41, length of shoulder 0.24, heart girth 0.49, chest width 0.22, withers height 0.38, front cannon height 0.27, circumference of front cannon 0.30, hind cannon height 0.29 and circumference of hind cannon 0.34. The estimates of genetic correlation ranged from 0.18 to 0.96 and those of phenotypic correlation varied from 0.16 to 0.83.     

应用大豆表型设计育种技术选育大豆品种齐黄34

大豆产量由群体结构和个体生产力共同决定。其中,群体结构由个体的结荚习性、株高、主茎节数、分枝数、叶柄和叶片等株型性状决定;个体生产力由单株有效荚数、每荚粒数和粒重等性状决定,这些性状都具有特定的遗传和变异规律。表型设计育种是根据农作物表型性状的遗传和变异规律,设计出理想的表型性状值并培育出理想品种的育种技术。大豆品种齐黄34就是根据生态环境、生产条件和市场需求,采用表型设计育种技术选育成的高产大豆品种,具有株型紧凑、个体生产潜力大等特点。     

表型轮回选择和混合选择改良小麦群体效应的研究

在吴兆苏等(1984)创建的小麦基础群体中,采用不同的选择方案,对不育株和可育株分别进行两轮选择。结果表明两轮选择显著地降低了可育株和不育株群体的株高。可育株群体株高的下降速率大于不育株群体。单株产量和单株穗数没有得到显著的改良。相关性状穗长、千粒重等出现负向间接选择效应。轮回选择通过选株间的互交,维持了不     

日本野生大豆中的四个种子蛋白和两个性状的多态及地理分布

本文电泳调查了日本1767野生大豆个体的种子胰蛋白酶抑制剂类型及频率分布。日本野生大豆存在两类型,即Tia和Tib,频率分别为94.5％和5.5％。从纬度上看,34°～38°带比其它纬度带有较高的Tib频率。本调查看到约1％的材料是Tia/Tib杂和体。 首次观察了3种蛋白的变异性。这些蛋白具有明显的多态性及地理分布差异。K1有3个形态:缺失体,快带和慢带;K2有两种形态:快带和慢带;B有两种形态:快带和慢带。本文提出这3种蛋白可以做为“等位酶”,用于野生大豆地理遗传分化的研究。 日本野生大豆的种皮过氧化物酶活性表型频率略高于中国,荧光型频率远高于中国。初步讨论了日本天然野生大豆群体的遗传变异,似乎由低纬度到高纬度地理变异的程度增大。     

Role of nucleolin in Ang II-induced phenotypic transformation of vascular smooth muscle cells

AIM: To investigate the effect of nucleolin on angiotensin II (Ang II)-induced phenotypic transformation of vascular smooth muscle cells (VSMCs). METHODS: Ang II was used to induce the phenotypic transformation of VSMCs. The spatial and temporal expression patterns of nucleolin, and the effects of Ang II on the expression of VSMC phenotypic transformation markers α-smooth muscle actin (α-SMA), calponin, smooth muscle protein 22 α (SM22α) and osteopontin (OPN) were investigated. The techniques of gene over-expression and RNA interference were used to assess the effect of nucleolin on the expression of Ang II-mediated VSMC phenotypic transformation markers. RESULTS: The expression of α-SMA, SM22α and calponin at the mRNA and protein levels was gradually decreased by Ang II stimulation, while the expression of OPN at mRNA and protein levels was gradually increased. The expression of nucleolin was gradually up-regulated in the VSMCs treated with Ang II at different concentrations for various duration (P<0.05). Ang II induced nucleolin translocation from the nucleus to cytoplasm. Over-expression of nucleolin promoted the VSMC phenotypic transformation induced by Ang II. Down-regulation of nucleolin suppressed the promotion of phenotypic transformation. CONCLUSION: Nucleolin promotes Ang II-induced phenotypic transformation of VSMCs, and its mechanism may be related to its function of cytoplasmic translocation.     

飞蝗表型可塑性研究进展

飞蝗在田间有群居型和散居型两种表型,两型间可以相互转变,这种转变是表型可塑性过程.表型可塑性是昆虫对环境变化的响应,通过表型改变来适应恶劣环境达到生存繁衍的目的.群居型和散居型蝗虫在体表颜色、外部形态、发育及生理特征、行为参数等方面都存在明显差异.总结蝗虫表型可塑性调控机制研究进展,并对未来趋势进行了展望,以期控制蝗虫...     

不同光照处理对绿萝表型可塑性的影响

[目的]研究不同光照处理对绿萝表型可塑性的影响。[方法]比较了叶面积、茎长、叶离心率和鲜重几项指标。[结果]不同的光照强度能显著影响绿萝叶片面积,且不同处理间差异显著;不同的光照强度能显著影响绿萝的茎长生长,且不同处理间差异极显著;不同的光照强度能显著影响绿萝叶片长、宽的生长,使叶离心率发生变化,改变其叶基的形状。[结论]为合理地开发绿萝资源,更好地发挥其生态意义和经济价值提供科学依据。