Microsatellite analysis of the genetic relationships between wild and cultivated giant grouper in the South China Sea

The giant grouper (Epinephelus lanceolatus) is a coral fish with high commercial value in Southeast Asia. In the present study, we isolated 11 microsatellite DNA markers, and analysed the genetic diversity and differentiation between cultured stocks and wild populations of the giant grouper originating from the South China Sea. A total of 390 alleles at 11 microsatellite loci were detected in 130 individuals from five different populations. The expected heterozygosity varied from 0.131 to 0.855 with a mean value of 0.623 and the observed heterozygosity varied from 0.145 to 0.869 with a mean value of 0.379. The allelic richness and heterozygosity studies revealed that the genetic diversity of the cultured population was significantly reduced when compared with that of the wild population. The F_is, pairwise F_st values, analysis of molecular variance (AMOVA), three-dimensional factorial correspondence analysis and structure analysis revealed significant population differentiation between the cultured stocks and the wild populations, among the three cultured populations and between the two wild populations. These differences may be caused by random genetic drift, the effects of artificial selection and founder effects. Our results will be useful in the management of cultured stocks and conservation of wild populations of the giant grouper.     

模糊聚类分析在中国伞形科当归亚族分类中的应用

针对伞形科前胡族当归亚族上属间界线划分的分歧,采用模糊聚类分析方法,在形态方面以属为分类单位,定量阐明了属间亲缘关系。化学方面,以裂解－气相色谱信息为分类依据肉获得的２７个种的数据揭示了当归亚族中属间的分类关系,结果表明,当归属和在中国分布的山芹属与广义当归属类群相近,并显示了东北长鞘当归和骨缘当归是一个较特殊的类群。     

Asymmetric Somatic Hybridization Between Wheat (Triticum aestivum) and Bromus inermis

Asymmetric hybridization was conducted between wheat and Brorrats inermis keyss which is a distanfiy related intergeneric plant (belonging to different tribe) of wheat and possesses some favorable traits, such as resistant to cold, drought and disease. Protoplasts isolated from young embryo-derived calli of common wheat ( Triticura aestivum L., tv. 99P, (AABBDD), 2n = 42) were fused with UV-treated protoplasts isolated from young embryo-derived calli of Bromus inermis by PEG method. Three clones (No. 1 ~ No. 3) were regenerated from the fusion products and differentiated into albino seedlings. The clones and the seedlings were all verified as hybrids by chromosome counting, isozyme and RAPD analysis. Their isozyme and RAPD pattern contained the characteristic bands of both parents as well as new band(s). The chromosome numbers of albino were in the range of 42~54 with small chromosomes of Bromus inerm/s and chromosome fragments. The above results confirmed that hybrid albinos were obtained.     

因子与巢式交配设计群体近交率的比较研究

探讨了因子和巢式交配设计群体近交率的形成机理,结果表明,这两种交配设计群体结构本身并不导致基近交率累积的差异。在育种选择情况下因子交配设计比巢式设计群体的近交率上升慢,而在完全随机留种和限制随机种情形这两种酱地群体近交率的影响没有差异,但在交配设计情况下,限制随机留种比完全随机留有有交地控制群体近交率的提高。这一结果显示,在动物的家畜遗传留种比完全随机留各 效地控制群体近交率的提高。这一结果显示,     

SEM Observation on the Structure of Cuticles on Leaf Inner Surface of Abies (Pinaceae) and Its Significance in Systematics

Comparative investigation of the inner surface of the needle cuticle of 36 species and 2 varieties of Abies under SEM has revealed that the characteristics of the intercellular flanges are rather distinct and four types can be distinguished: (1) Straight and developed single flange. This type is only represented by Abies bracteata D. Don. Morphologically, this species is also quite unique in the genus Abies and was once treated as a subgenus by Franco and Liu. Its special structure of the leaf cuticle observed here seems to support their treatment. (2) Double flanges. This type was first discovered in a leaf fossil of Abies from England. In modern plants of Abies, it is found only in the species from Central America. (3) Undeveloped single flange. This type is represented by a small group of Abies from the west and east coastal area of the Pacific Ocean. (4) Undulate and developed single flange. This type is represented by most of the species of Abies, including all the species in Europe and most species in Asia and North America. The flange types mentioned above seem to have some relationships with the geographical distribution of the species in the genus Abies, and their occurrence might have not been completely influenced by the habitats, hence the features of the intercellular flanges may provide good evidence for the subgeneric division of Abies. Based on our results and those from the previously published literature about the infrageneric treatments of Abies and the distribution of the fossils, we consider that western North America might be the diversity center of modern Abies. Florin once pointed out that the characters of the leaf cuticle in gymnosperms are of great significance for the generic andinfrageneric division. This viewpoint is strongly supported by our study on modern Abies.     

家蚕分子连锁图谱的构建及分子标记育种研究进展

国际蚕分子育种计划(International Silkworm Project)是Rhode Island大学的M.R.Goldsmith在1991年提出来的,也叫基因标记育种计划[1].该计划主要包括两步工作:第一步是制作蚕的分子基因图, 第二步是数量性状定位分析(简称QTL分析,也叫数量性状定位作图:QTL Mapping).最后利用分子标记直接在DNA水平进行重要经济性状(数量性状)的选择、固定,即实施"分子育种",用很短时间育成兼具高抗、强健、丝多、质优、易繁等特性的新蚕品种,本文对此进行简要介绍.     

秦岭南坡森林有蹄类群落组成与垂直分布特征

野生动植物种群和生物多样性的垂直分布模式是生态学研究中的重要问题,而目前对于大型兽类的垂直分布模式却了解较少。本研究以秦岭南坡森林生态系统中的有蹄类动物为对象,使用相机陷阱调查技术（camera-trapping）,系统的调查了研究区域内大中型兽类的分布情况。我们将研究区域按300 m垂直间隔划分为5个海拔段,分别计算各海拔段内目标物种的相对多度指数（Relative Abundance Index, RAI）和物种丰富度（species richness）,研究有蹄类动物群落的组成和垂直分布特征。2008年3~12月,共调查123个有效位点,在4 307个有效相机工作日中共记录到7种森林有蹄类动物。其中,羚牛（Budorcas taxicolor）为秦岭南坡有蹄类动物群落中的优势物种（平均RAI = 110.66）,种群数量最多;其次是野猪（RAI = 28.25）和斑羚（RAI = 25.10）;林麝（Moschus berezovskii）则是群落中种群数量最少的物种（RAI = 1.33）。在本研究所涉及的海拔梯度内,各物种种群数量的垂直分布模式为：羚牛和林麝为单峰型,种群数量在中间海拔段存在一个峰值,两侧递减;斑羚（Naemorhedus goral）为单调递增型（R2 = 0.84）,种群数量大体随着海拔梯度的升高而增加;小麂（Muntiacus reevesi）（R2 = 0.94）和鬣羚（Capricornis sumatraensis）（R2 = 0.79）为单调递减型,种群数量随着海拔梯度的升高而减少;野猪（Sus scrofa）和毛冠鹿（Elaphodus cephalophus）为复合型,分布模式较为复杂。整个有蹄类群落的物种丰富度的垂直分布表现为中峰模式,在1 700~2 300 m的中等海拔段最高,符合中域效应假说的预测。     

共聚焦激光扫描显微镜活体观察动脉粥样硬化家兔模型大脑皮质血管内血液缘流厚度的改变

目的:探讨在兔脑皮层动脉粥样硬化时血管内缘流厚度的变化。方法:用共聚焦激光扫描显微镜比较家兔脑皮质动脉内缘流厚度在正常、粥样硬化病理状态下的不同。结果:在血管直径为74.87±3.26μm的血管中血液缘流厚度在病理状态下随血管的舒张、收缩而发生改变;而在血管直径为94.33±2.84μm的缘流厚度在血管收缩时发生改变。结论:动脉粥样硬化的家兔模型中血液缘流厚度随血液的流变性质改变而改变。