易贡藏布沿岸种子植物组成及其区系特征分析

通过野外植被实地调查和资料整理分析,以易贡藏布沿岸种子植物为研究对象,对区域内种子植物科、属组成特征及不同海拔种子植物物种丰富度进行分析。结果表明,该区域共记录到种子植物87科257属428种。其中,裸子植物3科7属13种,被子植物84科250属415种。科属的分布区类型中除世界广布外,热带科的比重略高于温带科,而温带属的比重占优势。SD值(植物区系种系分化度)和TSR(转换后的物种丰富度)与海拔变化不具明显相关性。与邻近区域的植物区系R/T值(热带成分/温带成分)比较,发现该研究区与色季拉山的植物区系最为接近。

中国裸子植物物种丰富度空间格局与多样性中心

中国拥有世界上最丰富的裸子植物区系,对理解全球裸子植物分布变化与系统演化具有重要意义。我们利用中国天然分布的202种裸子植物的水平和垂直分布信息获得物种分布区范围,探讨了中国裸子植物在科、属、种水平的分布特点。总体上,中国裸子植物物种丰富度南高北低,山地裸子植物丰富度较高,平原和高原相对贫乏;随分类阶元变高,丰富度高值区域面积逐渐扩大,高值中心逐渐南移。占中国陆地面积5%的裸子植物最丰富区域内分布了85%的中国自然分布的裸子植物物种。我们将这些区域划分为6个裸子植物多样性中心:(1)东喜马拉雅—横断山脉—秦岭,(2)滇黔桂-南岭,(3)华中山地,(4)黄山—武夷山脉,(5)海南岛南部山地,(6)长白山(甑峰山附近)。各中心裸子植物区系之间的特点和联系反映了各自地理位置的差异和空间距离的隔离作用,其中横断山脉地区是中国裸子植物最重要的分化中心。

福建武夷山脉裸子植物区系与地理分布的研究

通过野外实地考察,研究了福建武夷山脉裸子植物区系与地理分布及种系分化特点。结果表明:福建武夷山脉是中国裸子植物多样性中心之黄山-武夷山脉中心的核心区域,裸子植物共有10科24属39种。其地理分布呈中间海拔膨胀型。裸子植物的区系具亚热带性质,随纬度升高热带分布的比例呈下降趋势,而温带分布和中国特有分布的比例则呈上升趋势。裸子植物种系分化强度表现出南低北高的变化特点。

言语相关基因FOXP2研究进展

目的综述FOXP2基因近几年来的研究现状和有待于解决的问题。方法参阅国内外相关文献对FOXP2基因的发现、在不同物种之间的进化、结构和功能做以综述。结果FOXP2的突变使其编码产物丧失了作为一种调控因子诱导大脑神经元迁移后分化的重要功能,影响了个体言语能力的发展。结论FOXP2基因是目前发现的第一个与语言有关的基因,该基因是人类进化过程中的选择性标记之一,与语言功能密切有关。

梵净山世界自然遗产提名地裸子植物区系与地理分布分析

通过野外实地考察和文献分析,研究了梵净山世界自然遗产提名地裸子植物区系与地理分布及种系分化特征。结果表明:提名地有裸子植物7科20属36种,是中国乃至世界裸子植物区系的关键组成,是贵州裸子植物分布的核心,北温带区系起源的松科(Pinaceae Lindl.)和东亚区系起源的三尖杉科(Cephalotaxaceae Neger)植物在区系构成中起关键作用。物种分布随海拔升高先增后减。区系具有明显的温带性质,区系起源早于中生代白垩纪,中国特有属丰富,是东亚裸子植物区系的原始和现代分布中心之一;区系成分随海拔升高热带成分减少,而温带和中国特有成分增加;按裸子植物分布区亚型的分类,裸子植物亚热带性质强,具有亚热带向温带的过渡性。属的区系分化强度低反映了寡种属多,区系的古老和残遗性强,科的区系分化强度高反映了区系分化能力强;种系分化强度由高海拔向低海拔递减。有各类珍稀濒危裸子植物27种,珍稀濒危程度高;有地方特有梵净山冷杉(Abies fanjingshanensis W.L.Huang.),新区域特有大明松(Pinus taiwanensis Hayata var.damingshanensis Cheng et L.K.Fu),西北缘分布的模式标本植物长苞铁杉(Tsuga longibracteata Cheng),有中国特有裸子植物28种,特有率高且独特。通过讨论,提名地是世界裸子植物物种多样性最丰富的山地,是东亚成分三尖杉科和北温带成分杉科(Taxodiaceae Warming)的现代分布中心;是亚热带裸子植物区系的典型范例,特有区系成分高,位于裸子植物东亚起源和分化的核心位置;拥有最为丰富的中国特有种,植物珍稀濒危程度高。这与提名地独特的地理位置、独立的山体和古老的地质历史密切相关。

广西宾阳县野生种子植物区系研究

通过实地调查并结合相关资料,对广西宾阳县野生种子植物区系进行统计与分析。结果表明:(1)迄今已知宾阳县有野生种子植物1081种,隶属于162科607属,其中裸子植物4科5属6种,被子植物158科603属1075种,体现植物区系种类繁多和物种多样性丰富。(2)区系中植物生活型齐全多样,其中木本植物种类(589种)多于草本植物种类(492种);木本植物中以灌木种类占优势,乔木次之,木质藤本植物也有一定数量;常绿树种(472种)明显多于落叶树种(112种)。(3)区系中科、属热带成分与温带成分的比值(R/T值)分别为3.71、3.41,体现较强的热带性质,但温带性质也有所分布,过渡性质较突出。(4)区系起源古老,分布有一些古老孑遗物种。(5)区系有中国特有属6属,有一定的中国特有种和广西特有种,体现较强的特有现象。(6)珍稀濒危物种和重点保护野生植物较丰富,有国家重点野生保护植物4种,隶属于4科4属,其中Ⅰ级重点保护野生植物1种和国家Ⅱ级重点保护野生植物3种(隶属于3科3属);有广西壮族自治区重点保护野生植物15种,隶属于5科13属;此外还分布其他一些稀有植物。(7)与乳源县、通道县、紫金县、木论自然保护区、下雷自然保护区等邻近地区种子植物区系相比,宾阳县区系综合指数大于下雷自然保护区而小于其他地区,表明其植物丰富度较低,种系分化度也最低;其属的热带属数/温带属数(R/T)值(3.38)大于紫金县(3.00)、木论自然保护区(2.16)、乳源县(1.53)和通道县(1.24)而小于下雷自然保护区(4.75),表明其热带性质仅次于下雷自然保护区而强于其他4个地区;聚类分析结果,宾阳县区系与紫金县关系密切,而与乳源县、通道县关系则较疏远。

Optimization of ISSR-PCR Reaction System and Preliminary Construction of ISSR Fingerprinting of Some Species in Bryaceae

[Objective] The aim was to provide molecular basis for the identification of species in the moss family Bryaceae by the construction of inter-simple sequence repeats （ISSR） fingerprinting. [Method] In order to seek standardizing PCR reaction set-up, an orthogonal design was used to optimize ISSR-PCR amplification system of Bryaceae in five factors （Mg2＋, dNTPs, primer, DNA template, Taq DNA polymerase） at four levels respectively. [Result] A suitable ISSR reaction system was obtained, namely： 20 μl reaction system containing 5 ng of DNA template, 0.2 μmol/L primer, 2.25 mmol/L MgCl2, 0.6 U of Taq DNA polymerase, 0.4 mmol/L dNTPs. Proper annealing temperature was found at 48-50 ℃.The above system and six ISSR-PCR primers were used for the PCR amplification of 14 samples from Bryaceae and the related species in Mniaceae. A total of 86 bands were amplified, all showed polymorphism. NJ cluster analysis showed a star-shaped cladogram. [Conclusion] The results manifested that ISSR fingerprinting could provide the appropriate degree of polymorphism at low taxonomic level, so it would be a useful tool to provide additional evidence for resolving taxonomic relationships at the species level of Bryaceae.

Genetic Differentiation of A and B Chromosomes Between Common Wheat and Wild Emmer as Revealed by RFLP Analysis

To investigate chromosome differentiation of genome A and B between common wheat and wild emmer wheat (Triticum turgidum var. dicoccoides (Koern.) Bowden), the authors conducted a RFLP analysis of the two species using 153 genomic, cDNA and chromosome_specific probes. 75.8% of the probes had detected hybridization polymorphism in at least one of the five restriction enzymes. However, the polymorphic probes were unevenly distributed among different homoeologous groups, between different genomes and in different regions of a single chromosome. Homoeologous group 1 possessed the highest level of polymorphism (96.2%), followed by group 6 and 2 (84.6% and 82.1% respectively). In contrast, only 60%-67% of probes of the other four groups was polymorphic. In most groups the number of probes capable of detecting B chromosome polymorphism was slightly higher than that revealing A chromosome difference (totally 51.8% vs 43.1%). In a single chromosome, RFLP was predominant in the distal region (65.1%) and showed a decreasing trend from the proximal (46.2%) to the pericentric (42.4%) regions. The results suggest that there exists a substantial amount of DNA polymorphism between the A and B chromosomes of common wheat and those of wild emmer wheat, indicating that a considerable degree of genetic differentiation has taken place in the A and B genoms of two species during evolution from wild emmer to common wheat. The extent of the genetic differentiation may vary among different homoeologous groups, between A and B chromosomes and in different regions of individual chromosome.

Mechanisms of species divergence through visual adaptation and sexual selection:Perspectives from a cichlid model system

The theory of ecological speciation suggests that assortative mating evolves most easily when mating preferences aredirectly linked to ecological traits that are subject to divergent selection. Sensory adaptation can play a major role in this process,because selective mating is often mediated by sexual signals: bright colours, complex song, pheromone blends and so on. Whendivergent sensory adaptation affects the perception of such signals, mating patterns may change as an immediate consequence.Alternatively, mating preferences can diverge as a result of indirect effects: assortative mating may be promoted by selectionagainst intermediate phenotypes that are maladapted to their (sensory) environment. For Lake Victoria cichlids, the visual environmentconstitutes an important selective force that is heterogeneous across geographical and water depth gradients. We investigatethe direct and indirect effects of this heterogeneity on the evolution of female preferences for alternative male nuptial colours(red and blue) in the genus Pundamilia. Here, we review the current evidence for divergent sensory drive in this system, extractgeneral principles, and discuss future perspectives [Current Zoology 56 (3): 285-299, 2010].

Studies on the Allelopathic Potential of Corn （Zea mays L.） Aqueous Extracts and Root Exudates

This investigation was carried out at Faculty of Agriculture and Forestry-University of Duhok/Kurdistan-Iraq. Three experiments were included in this investigation： （1） First experiment was a bioassay related to the germination performance, shoot and root development of corn （Zea mays L.） and peanut （Arachishypogaea） at two concentrations of root （3% and 1.5%） and shoot （12% and 6%） aqueous extracts of corn medium; （2） The second experiment dedicated to the intercropping of corn and peanut at four treatments; （3） While the third experiment involved the effect of peanut root exudation on growth of corn. Experiment results revealed that corn shoot and root water extracts highly inhibited seed germination of both corn and peanut, the inhibitory of shoot extract was more than root aqueous extract. While its effect on the seedling growth was vice versa as compared with control treatment, there was an increase in root and shoot length of both corn and peanut when grown in corn aqueous extracts. Intercropping experiment results has stimulated most traits of peanut under studying. Also for corn, there was apparent and significant increase in all characteristics as compared with control. It was further confirmed from the results of peanut root exudates that had all studied characters of corn were stimulated than the control treatment.

Application of restriction site amplified polymorphism (RSAP) to genetic diversity in Saccharina japonica

Restriction site amplified polymorphism (RSAP) was used, for the first time, to analyze the genetic structure and diversity of four, mainly cultivated, varieties of the brown alga, Saccharina japonica. Eighty-eight samples from varieties "Rongfu", "Fujian", "Ailunwan" and "Shengchanzhong" were used for the genetic analyses. One hundred and ninety-eight bands were obtained using eight combinations of primers. One hundred and ninety-one (96.46%) were polymorphic bands. Nei's genetic diversity was 0.360, and the coefficient of genetic differentiation was 0.357. No inbreeding-type recession was found in the four brown alga varieties and the results of the "Ailunwan" variety using samples from 2 years showed that the variety was becoming less diverse during the selection inherent in the breeding program. Genetic diversity and cluster analyses results were consistent with these genetic relationships. The results show the RSAP method is suitable for genetic analysis. Continuous inbreeding and selection could reduce the genetic diversity effectively; therefore periodical supervision is required.

Phylogeny and species differentiation of Mollitrichosiphum spp. （Aphididae, Greenideinae） based on mitochondrial CO1 and Cyt b genes

Phylogenetic analyses based on mitochondrial genes were conducted to reconstruct species relationships within the aphid genus MoUitrichosiphum （Aphididae, Greenideinae）. MP and Bayesian analysis results using COI and Cyt b datasets, and combined MP, ML and Bayesian analysis of both were consistent with a morphologically supported monophyly. Subdivision of the genus into two subgenera was strongly supported. Samples of each included species form monophyletic clade, respectively; and the result implied the valid status of related species in this genus. These results suggest some surprising hypotheses regarding the phylogeography of the genus： the uplift of the Tibetan Plateau, reorganization of major fiver catchments and the isolation of Hainan Island were probably important factors contributing to the diversification of species in this genus .

The impact of ancestral population size and incomplete lineage sorting on Bayesian estimation of species divergence times

Although the effects of the coalescent process on sequence divergence and genealogies are well understood, the vir- tual majority of studies that use molecular sequences to estimate times of divergence among species have failed to account for the coalescent process. Here we study the impact of ancestral population size and incomplete lineage sorting on Bayesian estimates of species divergence times under the molecular clock when the inference model ignores the coalescent process. Using a combination of mathematical analysis, computer simulations and analysis of real data, we find that the errors on estimates of times and the molecular rate can be substantial when ancestral populations are large and when there is substantial incomplete lineage sorting. For example, in a simple three-species case, we find that if the most precise fossil calibration is placed on the root of the phylogeny, the age of the internal node is overestimated, while if the most precise calibration is placed on the internal node, then the age of the root is underestimated. In both cases, the molecular rate is overestimated. Using simulations on a phylogeny of nine species, we show that substantial errors in time and rate estimates can be obtained even when dating ancient divergence events. We analyse the hominoid phylogeny and show that estimates of the neutral mutation rate obtained while ignoring the coalescent are too high. Using a coalescent-based technique to obtain geological times of divergence, we obtain estimates of the mutation rate that are within experimental estimates and we also obtain substantially older divergence times within the phylogeny [Current Zoology 61 （5）： 874-885, 2015].

Evolution of sexual size dimorphism and its relationship with sex ratio in carabid beetles of Genus Ceroglossus Solier

Although the degree of mate competition, given extreme differences in sex ratio, explains much of the pattern of male-biased size dimorphism among diverse taxa, it fails for some species which have potential for intense male competition for mates and yet exhibit little or no sexual size dimorphism （SSD）. This fact suggest that species with low SSD should be express the effect of evolutionary pressure in non-obvious geometrical shape promoted by sex ratio in an evolutionary time scale. To evaluate this hypothesis we used phylogenetic comparative method in a Bayesian framework to investigate the evolution of SSD and the role of sex ratio at inter-specific level in the species of Ceroglossus （Coleoptera： Carabidae）. In our results the proportion farthest from 1：1 is associated with more disparate body shape, even though the entire group has minimum variation in sex ratio, which is an intrinsic life history character of this group considering its phylogenetic conservatism or phylogenetic signal. We suggest that the sex ratio has determined the dimorphism degree during evolution of this group, since both traits have increased or decreased together during the species divergence （i.e. positive phylogenetic correlation： r2=0.85）. We suggest that morphological studies of SSD will benefit from using comparative method with Bayesian approaches to assess the effect of phylogenetic history and its uncertainty. Finally, this will be allow to researchers to quantify the uncertainty of specific evolutionary hypotheses accounting for observed sexual dimorphism patterns.

Genetic differentiation in two widespread, open-forest bird species of Southeast Asia （Copsychus saularis and Megalaima haemacephala）： Insights from ecological niche modeling

Ecological niche modeling has emerged as an useful tool in the investigation of the phylogeographic histories of species or communities in a region. The high biodiversity （oftentimes cryptic）, and complex geography and geological history of Southeast Asia particularly call for multipronged approaches in phylogeographic investigations. Past studies have focused on taxa that are associated with lowland rainforests, which is the dominant natural vegetation type. Here, we combine published phylogenetic data, ecological niche modeling and paleo-climate models to reveal potential drivers of divergence in two open-forest bird species, the oriental magpie-robin Copsychus saularis and Coppersmith barbet Megalaima haemacephala. In spite of broad overlap in current distributions, there are subtle differences in their climatic niches, which result in different responses to past climatic changes. For C saularis, both Last Glacial Maximum climate models indicated that the entire Sundaland was climati- cally suitable, while phylogenetic analyses found divergent eastern and western Sundaland lineages. We thus postulate that this genetic divergence was a result of past separations of coastal habitats into eastern and western portions due to the emergence of Sunda shelf as sea-level fell. The current separation of morphological subspecies in Borneo is maintained by low climatic suitability （high annual rainfall） in certain regions. The extirpation of M. haemacephala from Borneo and southern Malay Peninsula might have been driven by unsuitable conditions （high temperature seasonality） in central Sundaland and/or the lack of open woodlands. Our study shows that ecological niche modeling adds a powerful dimension to our attempt to understand lineage evolution in space [Current Zoology 61 （5）： 922-934, 2015].