教学课程资源库 更多>>

关键词： 农杆菌   Ti质粒   植物冠瘿   分子生物学研究   T-DNA转移   代谢酶基因   植物细胞   单子叶植物   Ri质粒   右边界  

关键词： 化学信号   植物   微生物   基因表达   转导  

摘要： 本文综述了近年来植物－微生物化学信号物质的发现和鉴定、化学信号传导的机理、相关基因的表达和调控等方面的研究进展；并提出存在的问题。

关键词： 嵩草属   繁殖系统   生物学   草甸   青藏高原  

摘要： 本文观察和总结了青藏高原蒿草属植物繁育系统的基本特点，并对其特别功能及其进化与适应意义进行了讨论。嵩草属植物具有两个显著的繁殖特点：发达的地下根茎营养繁殖系统和兼性的次级有性恢复系统。各类杂交、突变与染色体各种型式的变化在蒿草属植物中总是同营养繁殖同时存在的；发达的地下根茎营养繁殖系统不仅具有繁殖、传播扩散、占领新生态位的功能，而且还具有使高度适应性的类群或杂种复合类群保持高度纯系性和稳定性，使其优越的遗传基因组合型不至于在有性生殖过程中被破坏或丢失的优势。兼性的次级有性恢复系统使高度适应性和进化性的单纯群在次级遗传生态学过程中转变为有性可育，进一步加强了筛选和甑别适应与进化优秀基因的良性循环。蒿草属植物的繁殖系统蕴藏着极大的居群生态学、遗传生态学和环境适应机制，使蒿草属植物的进化潜力得到了极大的发挥。

关键词： ASPLENIACEAE   EVOLUTION   HYMENASPLENIUM   MOLECULAR PHYLOGENY   SPECIES   SYSTEMATICS   TAXONOMY  

摘要： In Aspleniaceae, Hymenasplenium is a well-defined group with dorsiventral creeping rhizomes, Members of Hymenaspleniom are widely distributed in the tropic zones of the world and have great variation in morphology and ecolgy, making it a good model group for plant systematics and evolutionary biology. I have worked on this group using techniques such as comparative morphology, ecology, cytology (for examining chromosomes and reproductive modes), phytochemistry and molecular biology. I considered the evolution of various phenetic characters based on a molecular phylogenetic tree which I recently obtained from sequence comparisons of rbcL, In this paper, I will summarize the results.

关键词： Gametophytes   Spores   Ferns   Sporophytes   Plants   Spore germination   Diploidy   Evolutionary genetics  

摘要： Ceratopteris (Parkeriaceae) is a pantropical genus of annual ferns possessing several features that make it exceptionally useful as a model plant system. The uniqueness of the homosporous fern life cycle allows the study of various phenomena at both the developmentally simple haploid gametophyte stage and at the complex vascular sporophyte stage. Consequently, both cellular and whole plant studies can be carried out simultaneously in a genetically natural and stable system. In genetic approaches, the ability to screen large numbers of mutagenized spores, along with the simple haploid genetics possible with the gametophyte stage and the ability to generate complete homozygotes from a single selfing, provide a powerful means of rapidly isolating and studying mutations. Ceratopteris gametophytes are developmentally simple. However, because they are autotrophic and possess several types of differentiated cells, they offer a number of opportunities for study. Control of germination responses, pattern formation and meristem development, spermatozoid differentiation, apogamy and apospory, pheromonal controls of sexual differentiation, as well as a variety of biochemical/physiological traits can be studied using various approaches. At the same time, the sporophyte provides a typical vascular plant system for study of a variety of developmental, genetic or biochemical/physiological phenomena. Recent and ongoing improvements in culture techniques, along with increased use of molecular approaches, will substantially expand the use of Ceratopteris as a model plant system.

关键词： Gametophytes   Spores   Plants   Sporophytes   Spore germination   Ferns   Actins  

摘要： We have successfully utilized Ceratopteris richardii as a pedagogical tool in introductory and upper-division investigative exercises and in independent research projects. Undoubtedly, this is one of the simplest and easiest to implement biological systems in educational applications. Plants, especially gametophytes, are readily maintained in culture and can be used as a means to explore a wide array of biological phenomena, research tools, and techniques. This fern affords the advantage of rapid growth, especially for studies of growth regulation, development, and genetics. It enables experimentation on single cells and subsequent manipulation of differentiation into multicellular organisms. Hundreds of individuals may be maintained in a single petri dish, thus facilitating observation of population dynamics and genetics.

关键词： 台湾杉   生物学特性   保护措施  

摘要： 本文全面地综述了我国一级国家重点保护植物台湾杉的生物学特性，其中有外部形态特征，内部结构包括首端、叶片、树皮及木材结构，雌雄配子体与胚胎发育，花粉和染色体。此外还有台湾杉的组织培养、地理分布，生态学与群落学特性等。最后，本文作者还初步分析了台湾杉的濒危原因，并提出了具体保护措施。

关键词： 长苞铁杉   铁杉属   生物学特性   保护措施  

摘要： 长苞铁杉（ＴｓｕｇａＩｏｎｇｉｂｒａｃｔｅａｔａ）属松科铁杉属，长苞铁杉组（Ｓｅｃｔ．ＨｅｏｐｅｎｃｅＫｅｎｇｅｔＫｅｎｇｆ．），为我国特有树种；现正处在濒危状态，已被列为国家三级保护植物。本文比较系统地综述了长苞铁杉的生物学特性，包括其外部形态、内部结构、染色体核型、地理分布、生长特性及材性、生态学和群落特性等。关于长苞铁杉的分类位置，一直争论不休。作者在比较了各种分类观点后，根据上述特性的分析结果，支持建立长苞铁杉属（Ｎｏｔｈｏｔｓｕｇａ）的主张。最后，文章分析了可能引起长苞铁杉濒危的原因，并提出了两点保护措施。