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关键词： 苔草   种子形态特征   发芽率   千粒重  

摘要： 对从北京山区采集及外地引种驯化的扁杆苔草(Carex planiculmis)、尖嘴苔草(***)、披针苔草(***)、青绿苔草(***)、涝峪苔草(***)等18种苔草种子的形态特征、千粒重、发芽率进行研究。结果表明,18种苔草种子形态特征、千粒重、发芽率差异较大。翼果苔草(***)、溪水苔草(***)、疏穗苔草(***)种子明显小于其他种子,涝峪苔草种子体积最大,千粒重最高,达3.3g;KT种子较大,发芽率最高,达94%;长嘴苔草(***)始发芽时间最早,但其持续发芽时间最长,发芽率63%;短鳞苔草(***)始发芽时间较早,持续发芽时间较短,但其发芽率较低;涝峪苔草、披针苔草、脚苔草(***)、尖嘴苔草发芽率较高,均超过55%,但持续发芽时间较长;麻根苔草(***)始终未发芽,异鳞苔草(***)、溪水苔草分别在第25天、第46天发芽后,发芽数一直没有增加,发芽极其困难。本研究结果可为鉴别苔草种类提供科学依据,并为研究种子的萌发特性、选育优良苔草种质资源、提高推广应用力度提供基础资料。

关键词： 类受体激酶   CrRLK1-L   信号传导  

摘要： 植物CrRLK1-L亚家族类受体激酶的胞外域具有新颖结构基序,但功能大都未知.该家族成员广泛存在于被子植物中,但在动物和微生物中不存在其同源物.CrRLK1-L家族成员相对较少,但组织表达非常广泛.它们定位于细胞质膜上,并且部分成员的定位还具有极性,这与其参与雌雄配子体的识别和受精作用密切相关.该家族成员普遍具有激酶活性,该活性对其功能的发挥至关重要.目前仅报道在拟南芥中参与助细胞与花粉的识别和调控营养组织的细胞伸长,但参与这些生物学过程的作用机制似乎独立于已知的信号通路之外,可能有自身独特的信号传导机制.所以对这一类具特有结构基序的类受体激酶基因的功能研究,将有助于解析植物特有生物学过程的分子作用机制,特别是在植物有性生殖过程中,合理利用这些分子开展育种实践对未来农业生产具有潜在的应用价值.

标准号: NF X31-206-2011

摘要： La présente Norme internationale décrit une méthode de détermination de l'inhibition de la croissance et de la capacité de reproduction des plantes supérieures par les sols dans des conditions contrôlées. Deux espèces sont recommandées: une variante de colza à cycle rapide (Brassica rapa CrGC syn. Rbr) et l'avoine (Avens sativa). Il convient que la durée de l'essai soit suffisante pour inclure les points de mesure chroniques qui apportent la preuve de la capacité de reproduction des plantes soumises à l'*** utilisant des sols d'essai naturels provenant, par exemple, de sites contaminés ou de sols réhabilités, et en comparant le développement des plantes testées dans ces sols à celui des plantes testées dans les sols de référence ou les sols témoins standard, l'essai peut permettre d'évaluer la qualité du sol, notamment sa fonction d'habitat des plantes.L'Annexe A décrit des modifications permettant d'exploiter l'analyse chronique des plantes pour les essais de substances ou de produits chimiques incorporés dans le sol. En préparant une série de dilutions d'une substance dans des sols témoins standard, il est possible de déterminer les mêmes points de mesure afin d'évaluer la toxicité chronique de ces substances ou de ces produits chimiques. Cette méthode n'est pas applicable aux substances volatiles, c'est-à-dire celles pour lesquelles H (constante de Henry) ou le coefficient de partage air/eau est supérieur à 1, ou pour lesquelles la pression de vapeur à 25 oC est supérieure à 0,013 3 Pa à 25 oC.

关键词： 硒   植物   生物学效应  

摘要： 随着对硒元素的逐步认识,研究者发现其在植物中的生物学效应十分显著。文章从硒对植物生长发育和提高作物产量与品质的作用、对种子萌发的影响、对根系活力及其能量代谢的影响等等方面做一综述。

关键词： MOLECULAR biology   BIOMOLECULES   BIOACTIVE compounds   BINDING sites (Biochemistry)   PLANT physiology   PLANT hormones   MUTAGENESIS  

摘要： Structural biology efforts in recent years have generated numerous co-crystal structures of bioactive small molecules interacting with their plant targets. These studies include the targets of various phytohormones, pathogen-derived effectors, herbicides and other bioactive compounds. Here we discuss that this collection of structures contains excellent examples of nine collective observations: molecular glues, allostery, inhibitors, molecular mimicry, promiscuous binding sites, unexpected electron densities, natural selection at atomic resolution, and applications in structure-guided mutagenesis and small molecule design.

关键词： Chemical biology   Flowering  

摘要： The article presents a study on the Flowering Locus T's (FT) 14-3-3 protein links as transcription factor, which initiates flowering in the shoot apex of Arabidopsis thaliana and rice. It shows that interaction in FT and transcription factor FD triggers rice's floral organ formation. It says that the findings on yeast two-hybrid screen identified as GF14 bridge FT and FD interaction, which influences transcription. It adds the biological mechanisms in florigen activation complex (FAC) model.

关键词： 植物DNA甲基化   DNA甲基转移酶   5-甲基胞嘧啶  

摘要： DNA甲基化是指生物体在DNA甲基转移酶的催化下,以S-腺苷甲硫氨酸为甲基供体,将甲基转移到特定的碱基上的过程,是在不改变DNA分子一级结构的情况下对DNA序列进行的一种表观遗传修饰.在植物中,DNA甲基化在基因表达、细胞分化和生长发育过程中均发挥着重要的调节作用.概述了植物DNA甲基化的特征,并对DNA甲基化的机制、维持及其在植物中的生物学意义进行了讨论.

关键词： 植物生物学   教学改革   教学手段   考评体系  

摘要： 高校如何培养适应社会主义市场经济发展所需要的具备较高专业知识素养和创新精神的人才,正成为高等教育创新发展研究的热点议题之一.本文通过更新植物生物学教学内容,构建新的模块式课程体系,实行灵活高效的教学手段和全面综合的考评制度,探讨了教学改革的必要性和进行教学改革的主要方法,积极培养学生的创新意识和自主学习能力,为推动植物生物学的教学改革提出了一些建议.

关键词： Species concepts   Systematics   Phylogeny   Taxonomy  

摘要： Isolation followed by morphological identification was the traditional basis of all earlier endophyte studies. However, the use of molecular phylogenetics has become increasingly common in the identification of fungal endophytes, and during the period of 2007-2010 there were approximately 200 publications that reported data obtained using this approach. This new methodology involves using sequence data from isolates or whole DNA from plant substrates, which are amplified using fungus- specific primers. The data obtained are compared with sequences downloaded from public databases such as GenBank and then used to construct phylogenetic trees. The major problem with this approach is that much of the sequence data in these databases has been shown to be from isolates that were incorrectly named. In some species, as much as 86% of the sequences available are not from the organism whose name has been applied to the sequence in question. The use of these GenBank sequences to identify endophytic isolates by sequence similarity simply perpetuates the problem of wrong species identification, and any lists of endophytes established by such methods are likely to be highly erroneous. It is recommended that comparisons of sequence data be made using sequences from type species, and if such sequences are not available, then the data must be treated with caution.

关键词： Urban flora   Pollinosis   Allergy   Ornamental flora   Urban ecology  

摘要： Comparative ecological and aerobiological analyses of ornamental urban flora in the cities of Crdoba (Spain) and Ascoli Piceno (Italy) identified a group of plants with allergenic pollen whose behaviour is influenced by a number of factors. The geographical position and the resulting climate of both cities favoured the presence of Mediterranean species. In Crdoba, strongly allergenic evergreens introduced during the Moorish period predominated (Cupressus sempervirens, among others), while in the urban area of Ascoli Piceno, Pinaceae were abundant. In both cities, many species of American origin have been introduced for aesthetic reasons, contributing to an increase in the overall allergenicity of urban greenery. The pollen spectrum differed between the two cities: airborne Oleaceae and Cupressaceae pollen abounded in Crdoba, whilst allergenic pollen from surrounding natural environments (Corylaceae) predominated in Ascoli Piceno. These results pointed to a large number of potentially allergenic species in cities, thus highlighting the importance of greater ecological and aerobiological knowledge of allergenic species of urban ornamental flora. Avoidance of more allergenic species when planning new urban green areas could ensure healthier environments for pollen-allergy sufferers.