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1.
害虫天敌的植物支持系统   总被引:7,自引:0,他引:7  
保护天敌,使天敌长期有效地控制害虫是保护性生物防治的核心内容。其中,植物在维持和促进天敌控制害虫中的重要性和作用越来越受到关注。本文概述了各种支持天敌发挥效能的植物类群,论述了蜜源植物、储蓄植物、栖境植物、诱集植物、指示植物、护卫植物等在支持天敌生存和繁殖方面的生物功能,评述了研究和应用这些植物时需注意的问题,提出了科学利用这些植物以维持和增强农业生态系统中天敌发挥控害作用的植物支持系统,并指出了由于对这些植物类别的界定和定义模糊所带来的不便,给出了相应的建议。  相似文献   

2.
概述了中国140多个植物园过去50年发展的历史过程、分布和特征,以及植物园在研究、保护、展示和利用生物多样性等方面的功能.评述了中国植物园早期在经济作物烟草、药用植物薯蓣和野生果树资源研究中对社会和经济发展的贡献,以及近年来在种子科学、物种保护、经济植物引种驯化和育种等方面的理论和应用研究成果.介绍了中国植物园活植物收集的现状.其中木兰科、姜科、苏铁类、药用植物、猕猴桃属和杜鹃属等收集圃的建设已属世界领先.介绍了植物园科普和旅游的发展和中国植物园特有的盆景艺术园和硅化木收集园.  相似文献   

3.
中国植物园五十年   总被引:9,自引:0,他引:9  
概述了中国 14 0多个植物园过去 5 0年发展的历史过程、分布和特征 ,以及植物园在研究、保护、展示和利用生物多样性等方面的功能。评述了中国植物园早期在经济作物烟草、药用植物薯蓣和野生果树资源研究中对社会和经济发展的贡献 ,以及近年来在种子科学、物种保护、经济植物引种驯化和育种等方面的理论和应用研究成果。介绍了中国植物园活植物收集的现状。其中木兰科、姜科、苏铁类、药用植物、猕猴桃属和杜鹃属等收集圃的建设已属世界领先。介绍了植物园科普和旅游的发展和中国植物园特有的盆景艺术园和硅化木收集园  相似文献   

4.
Arnica montana L., like many endangered species, does not give stable yields in commercial plantations. Other Arnica species were investigated for their pharmaceutical activity and A. chamissonis Less., was confirmed as a pharmaceutical substitute for A. montana, extracts having on average 40% higher inhibition of lipoxygenase activity and reduction of superoxide and hydroxyl free radicles on a tissue dry weight basis. A micropropagation protocol was established for A. chammisonis and a plantation of 10,050 plants was established with 0.9% microplant loss at the weaning stage. The plantation is now in commercial production. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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植物在复杂的环境中进化出了各种反应来应对危害,其中糖基化作用就是植物利用的一种主要的生理机制.糖基化作用通过改变受体化合物的生物活性及其细胞内的定位来降低外物质对自身的影响,从而达到植物体生理代谢的稳态.植物中的糖基转移酶就是专门负责实现这种糖基化反应的酶类.简要概述了糖基转移酶在植物抗性过程中的研究方法、分类及生物学功能,并对其研究方向加以展望.  相似文献   

7.
植物引种驯化对近500年人类文明史的影响及其科学意义   总被引:3,自引:0,他引:3  
近500年来, 植物引种驯化及其广泛栽培深刻改变了世界农业生产的格局, 对促进人类社会文明进步产生了深远的影响。无论在西方殖民地发展史还是在我国明清发展史中, 每一种重要栽培植物的成功引种和驯化, 都对历史进程产生了不可估量的作用。活植物收集是植物园的核心和“灵魂”, 传承了现代植物园几个世纪科学研究的脉络和成就。活植物收集是植物园科学研究的基础和支撑平台, 也是当前和未来发展的根本。基于活植物收集的植物园研究工作具有多学科综合的特征, 既对基础生物学研究具有重要意义, 也与经济繁荣、社会发展和人类日常生活密切相关。  相似文献   

8.
安徽宿州大方寺林区植物种类及其资源的初步调查   总被引:3,自引:0,他引:3  
大方寺位于淮北平原萄丘陵地带,天然次生林属于暖温带叶阔叶林。由于自然条件复杂,植物种类丰富,木本植物130余种,草本植物100余种;植被类型多种多样,主要群落为:青檀(Pterooeltis tatarinowii)、牡荆(Witex negundo)、华隐子草(Cleistogenes chinensis)群落,栓皮栎(Quercus wvriabilis)、五角枫(Acer mono)、牡荆(Vitex negundo)裂稃草(Schizachyrium brevifolium)群落和黄连木(Pistacia chinensis)、五角枫(Acer mono)、扁担杆(Creuia biloba)、沿阶草(Ophiopogon bodinievi)群落等三种。大方寺植物资源丰富,具有用材经济植物的约60余种,药用植物200余种,香料及密源植物10余种,纤维植物30余种,庭园观赏植物40余种。  相似文献   

9.
朱佳兴  周慧  熊育久  严恩萍  莫登奎 《生态学报》2021,41(16):6665-6678
崖壁植物具有不可及或不易及的特点,有关崖壁植物的调查一直面临着高成本、高风险和难鉴定的难题。本研究创新性地提出一种采用无人机近景摄影技术对崖壁植物拍照及专家鉴定的调查方法,通过分析崖壁植物群落的Margalef、Simpson与Pielou这3种多样性指数的变化,探究海拔、光照、立地条件与水汽条件这4种因子对崖壁植物多样性的影响。研究结果表明:本次调查共发现崖壁植物267种,分属于58科、140属;崖壁植物物种数目与海拔高度变化服从正态分布,物种数量在中海拔700-800m达到峰值,Simpson指数与Pielou指数在低海拔时达到最高,随海拔的升高而下降,但不表现出明显的变化规律;崖壁植物在不同的立地条件下,植物群落的物种组成、优势种类与出现频率均有所不同;崖壁植物的相关性分析显示,在光照条件出现差异或立地条件不同时,崖壁植物各指数之间存在着不同的显著性关系;近水崖壁植物与对照组的分析结果对比显示,崖壁植物的数量与物种组成受崖壁间水汽条件的影响,崖壁水汽条件越高的地区有着更丰富的植物种类。本研究表明崖壁植物的分布特征是受海拔、光照、立地条件以及水汽条件等多因素的综合作用而成。  相似文献   

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Abstract

Under in vitro culture conditions, plants may present physiological and anatomical disorders, which can interfere negatively after ex vitro transfer. The aim of this investigation was to analyze the impacts of natural ventilation and sucrose supply on the anatomy and physiology of Vriesea imperialis. Plants previously grown in vitro were transferred to culture medium containing 0, 15, 30 or 45?g L?1 sucrose. Three different culture container sealing systems were tested: lids with a green filter (81.35 gas exchanges per day), yellow filter (13.09 gas exchanges per day) or lids with a yellow filter covered with three layers of transparent polyvinylchloride (PVC) film (blocking fluent gas exchange). Sucrose concentrations influenced thickness, lignin and suberin deposition of exodermis cell wall. The modifications verified in leaves, such as higher density of stomata and trichome scales, showed that sucrose can induce osmotic stress in the plants. Photomixotrophic conditions, using containers with intermediate rate of gas exchange (yellow filter) and with 15–30?g L?1 sucrose, produced an improvement in the growth traits and did not induce anatomical and physiological disturbances.  相似文献   

13.
药用植物细胞的选育与培养生产次级代谢产物   总被引:1,自引:0,他引:1  
目前,在医药行业的销售和研发领域中,植物药是健康产业的热点。然而长期的盲目采挖已造成我国当前药用植物资源的匮乏。为解决这一问题,实现药用植物资源的可持续利用,人们从药用植物细胞的选育、细胞培养生产药用植物药用成分等方面进行了研究。本文概述国内外药用植物细胞的选育和大规模培养技术研究中已取得的进展,并提出了目前存在的问题和今后研究的发展方向。  相似文献   

14.
李钧敏  董鸣 《生态学报》2011,31(4):1174-1184
寄生植物是生态系统中的特殊类群之一。植物寄生可以驱动生态系统中生物与非生物因子的变化,在生态系统结构与功能中起关键作用。寄生植物可以通过对寄主营养的集聚、改变凋落物的质量与数量、改变根的周转与分泌物格局、改变土壤水势,从而影响土壤理化特性。寄生植物会改变寄主的行为,改变寄主与非寄主植物之间的相互作用,从而影响植物群落的结构、多样性和动态,进而影响植被演替和植被生产力等。寄生植物与寄主均可被消费者取食,可直接或间接地影响生态系统的食草动物,包括草食昆虫等。寄生植物与寄主的其它寄生物存在竞争关系,可以直接或间接地影响寄主的其它寄生植物或病原真菌。寄生植物可以明显地改变土壤地球化学循环,将固有的不可动的成分转变为可利用的营养成分,改变土壤生物群落的结构与功能,从而显著影响地下生物群落。这些表明,植物寄生对生态系统的结构和功能有重要影响。针对特殊的被入侵的植物群落,该地寄生植物可以通过影响入侵植物寄主的生长、繁殖、生物量分配格局,改变土壤的理化特性,促进非寄主的非优势本地植物的生长,从而改变被入侵植物群落结构与多样性,达到生物防治及生态恢复的目的。  相似文献   

15.
Phylogenetic systematics (cladistics) is a theory of phylogeny reconstruction and classification widely used in zoology. Taxa are grouped hierarchically by the sharing of derived (advanced) characters. The information is expressed in a cladogram, a best estimate of a phylogeny. Plant systematists generally use a phenetic system, grouping taxa on overall similarity which results in many groups being formed, at least in part, on the basis of shared primitive characters.
The methods of phylogenetic systematics are used to create a preliminary cladogram of land plants. The current classification of land plants is criticized for its inclusion of many groups which are not monophyletic.
Objections to the use of phylogenetic systematics in botany, apparent convergences within major groups and frequent hybridization, are shown to be invalid. It is concluded that cladistic analysis presents the best estimate of die natural hierarchy of organisms, and should be adopted by plant systematists in their assessment of plant interrelationships.  相似文献   

16.
Summary Protein changes occurred in callus cells of hypersensitive tobacco (Nicotiana tabacum var. Xanthi-nc) 72 hr after inoculation with tobacco mosaic virus and incubation on a minimal growth medium. Two protein bands, serologically related to viral coat protein, were obtained from extracts of infected cells following electrophoresis on 7% and 10% polyacrylamide gels. An additional, slower migrating protein, perhaps due to virus-induced stimulation of a host protein, also was detected. Although local lesions appeared on callus after 40 hr of incubation, four proteins previously reported in lesion-bearing hypersensitive tobacco leaves were not found. The possible significance of this and the usefulness of a callus-TMV system as a tool to study virus-induced protein changes are discussed. Michigan Agricultural Experiment Station Journal Paper No. 7191.  相似文献   

17.
The creation of new populations of rare and endangered plant species has become well‐established as a standard technique in conservation and restoration ecology. However, much remains unknown about the actual rates of success or failure of such reintroductions. Recent research suggests that in part this reflects under‐reporting of failures. In 2000, the authors published a paper reporting rates of success in reintroducing eight perennial plant species into two reserves near Boston, MA, in 1994–1995. In 2010, the authors conducted a recensus of the experimental sites 15 years after reintroduction; almost all the populations reported in 2000 had disappeared. The implications for reintroduction methodology, with respect to establishing and reporting both successful and unsuccessful experiments are discussed.  相似文献   

18.
A large number of plant macrofossils from several Middle to Upper Miocene localities from Iceland have been studied. The fossil material includes four ferns and fern allies, seven conifers, and about 40 species of flowering plants. Betula islandica and Salix gruberi are described as new species. Coniferous twigs previously ascribed to the genus Sequoia are shown to belong to Cryptomeria based on macro‐morphological and epidermal features. Fossil plants from Iceland are compared with coeval fossil taxa from Europe and North America and with living plants. The main finding is that the Miocene flora of Iceland belongs to a widespread Neogene northern hemispheric floral type including plants whose representatives are restricted to East Asia, North America and to western Eurasia at the present time. Previously inferred conspicuous similarities to North American modern equivalents appear to be misleading. The type of vegetation in four plant‐bearing sedimentary formations from the late Mid Miocene to Late Miocene, the 12 Ma Brjánslækur‐Seljá Formation, the 10 Ma Tröllatunga‐Gautshamar Formation, the 9–8 Ma Skarðsströnd‐Mókollsdalur Formation, and the 7–6 Ma Hreðavatn‐Stafholt Formation, corresponds to a humid temperate broadleaved (deciduous)–coniferous mixed forest dominated by Betulaceae, Fagaceae and Acer. Changes in species composition in the sedimentary formations reflect a shift from warm temperate (Cfa climate) to cool temperate (Cfb climate) conditions from the late Mid Miocene to the latest Miocene. This shift was connected to repeated phases of extinction and colonization. Specifically, one set of thermophilic taxa including Magnolia, Liriodendron, Sassafras and Comptonia went extinct between 12 and 10 Ma, and appears to have been replaced by another set of thermophilic taxa in the 10 Ma formation (Juglandaceae aff. Pterocarya/Cyclocarya, Rhododendron ponticum type). The 9–8 and 7–6 Ma formations are characterized by taxa that migrated to Iceland from Europe, such as Fagus gussonii, Betula cristata and Pterocarya fraxinifolia type. Although there is convincing evidence that plants colonized Iceland both from North America and Europe until 12 Ma, migration in the younger formations (9–8, 7–6 Ma) is suggested to have occurred mainly from Europe. © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 149 , 369–417.  相似文献   

19.
植物虫瘿   总被引:3,自引:0,他引:3  
虫瘿是造瘿昆虫诱导植物组织不正常生长产生的,它们通过释放某些酶或者植物激素刺激寄主植物细胞增大或增殖产生了特异形态的虫瘿,而这种特异形态就是造瘿昆虫遗传基因的体外表达。但虫瘿产生的分子机制不是十分清楚,文章主要对目前植物虫瘿的形态特征、形成机制等方面进行综述。  相似文献   

20.
在沙基质的人工湿地中植物多样性能够提高污水去除效果,但无基质水生系统中植物多样性对除氮效应的影响还未知.本研究在45个水培微宇宙(53 cm×37.5 cm×18.5cm)中配置了4个物种丰富度梯度(1、2、3和4),并定期供给硝氮为唯一氮形态的模拟污水,氮载荷率为548.5 gN· m-2 ·a-1.结果表明:物种丰富度对出水中氮去除有显著效应,4个种系统出水总无机氮浓度(54.3 mg·L-1)明显低于单种系统(129.0 mg·L-1);物种丰富度显著提高群落生物量,4个种微宇宙系统群落总生物量为1621.6 g·m-2,高于单种群落的1032.7 g·m-2.水培微宇宙的氮平均移除速率为466.8 g N·m-2·a-1,不低于已有报道的全尺度人工湿地的去除能力,同时,4个种的系统比单种系统约高13%,因而可以通过物种多样性配置提高人工湿地效能.  相似文献   

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