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1.
同色兜兰及其亲缘群的研究   总被引:4,自引:0,他引:4  
讨论了兰科兜兰属(Paphiopedilum)中的同色兜兰(P.concolor(Lindl.)Pfitz.)、巨瓣兜兰(P.bellatulum(Rchb.f.)Stein)及其近亲的异同与亲缘关系,并描述了3个新分类类群:云南的文山兜兰(P.wenshanense Z.J.Liu et J.Y.Zhang)和广西的大化兜兰(变种)(P.concolorvar.dahuaense Z.J.Lir  相似文献   

2.
彩云兜兰及其近缘种的研究   总被引:3,自引:0,他引:3  
简要讨论了彩云兜兰及其近亲种的亲缘关系;描述了两个新种:缅甸兜兰Paphiopedilum burmanicum J.Y.Zhang et Z.J.Liu和短唇兜兰Paphiopedilum brevilabium Z.J.Liu et J.Y.Zhang;并提供了一个图版和有关5个种的分种检索表。  相似文献   

3.
兜兰属宽瓣亚属(广义)的补充研究   总被引:1,自引:0,他引:1  
对新种小囊兜兰Paphiopedilum globulosum与新变种扁球兜兰P.micranthum var.oblatum作了描述与绘图。两者均为采自云南东南部的栽培植物,与硬叶兜兰P.micranthum近似。但小囊兜兰具有宽得多的叶(宽2.8~3.4cm),先端多少呈钩状、宽1.1~1.2cm的唇瓣,以及与唇瓣囊口几乎同样大小的退化雄蕊,而扁球兜兰则叶宽2.2~3 cm,唇瓣扁球形,囊深不超过1 cm,可区别于硬叶兜兰。上述种类均属于宽瓣亚属(广义)。该亚属有16个种产中国、越南或两地共有。本文提供了分种检索表。  相似文献   

4.
《广西植物》1994,(4):295-296
狭叶紫毛兜兰狭叶紫毛兜兰Paphiopedilumvillosum(lindl.)Pfitz.var.annamenseHort.绘图:何顺清栽培及配文:黄广宾,俸宇星狭叶紫毛兜兰(Paphiopediopedilumvillosum(Lindl.)...  相似文献   

5.
兜兰属宽瓣亚属(广义)的被充研究   总被引:5,自引:0,他引:5  
对新种小囊兜兰Paphiopedilum globulosum与新变种扁球兜兰P.micranthum var.oblatum作了描述与绘图。两者均为采自云南东南部的栽培植物,与硬叶兜兰P.micranthum近似。但小囊兜兰具有宽得多的叶(宽2.8-3.4cm),先端多少呈钩状、宽1.1-1.2cm的辱瓣,以及与唇瓣囊口几乎同样大小的退化雄蕊,而扁球兜兰则叶宽2.2-3cm,唇瓣扁球形,囊深不超过1cm,可区别于硬叶兜兰。上述种类均属于宽瓣亚属(广义)。该亚属有16个种产中国、越南或两地共有。本文提供了分种检索表。  相似文献   

6.
心启兜兰,兜兰属宽瓣亚属的一个新增种   总被引:3,自引:0,他引:3  
描述了兰科兜兰属的一个新种——心启兜兰Paphiopedilum singchii Z.J.Liu et J.Y.Zhang。模式标本系深圳市梧桐山苗圃总场的栽培植物。原植物可能采自云南南部近中越边境处。  相似文献   

7.
亨利兜兰(Paphiopedilumhenryanum)是G.F.Braem于1987年发表的兰科兜兰属新种。其种名来自英国人亨利(A.Henry)(1857—1930)的姓氏,以纪念他19世纪末在中国卓有成就的植物采集和发现工作。亨利兜兰产于我国云...  相似文献   

8.
以植株的生长状况、整株姿态、叶片观赏性、开花性、花形、花色和花朵观赏期为评价指标,利用灰色关联分析,对我国原产的27种兜兰属植物的观赏价值进行了综合评价并分析了它们在华南地区的应用前景。结果表明:多花长瓣型的飘带兜兰与理想种的关联度最高,达到0.7304,是最值得在华南地区栽培的兜兰种类,其次为白旗兜兰。而紫纹兜兰、汉氏兜兰;文山兜兰、格利兜兰、带叶兜兰、亨利兜兰、同色兜兰,它们的关联度系数超过0.6;紫毛兜兰、巨瓣兜兰、红旗兜兰、天伦兜兰、长瓣兜兰、根茎兜兰的关联度均超过0.5;也是值得推广兜兰种类;杏黄兜兰、硬叶兜兰、白花兜兰由于生长状况差、开花性差等原因与理想种的关联度分别只有0.1900、0.1921、0.2917,不适于华南地区栽培;其它9种兜兰的关联度虽然介于0.35~0.50之间,但其中有些种类如虎斑兜兰、麻栗坡兜兰、波瓣兜兰、德氏兜兰等由于具有独特的观赏价值和育种潜力,也是值得在华南地区栽培的兜兰种类。  相似文献   

9.
为建立小叶兜兰的繁育技术体系,本研究通过无菌播种的方法,辅以TTc生活力测定等方法,比较了小叶兜兰种子在授粉后不同发育时期和培养条件下的萌发率,对小叶兜兰种胚的发育过程进行了显微观察,探讨种胚发育程度与萌发的关系。结果表明,小叶兜兰种胚的发育阶段对萌发的影响最大,授粉后255d的种子萌发率最高(90.71%),该阶段种子仍呈白色但微干燥,种胚刚发育至球形胚阶段,胚柄尚存。1/4MS和1/2MS为小叶兜兰适宜的基本培养基,添加100mg·L^-1的土豆汁对小叶兜兰的无菌萌发有良好的促进作用。  相似文献   

10.
由于过度收集和对原生境地的破坏,我国野生兜兰已濒临灭绝,对其进行迁地保护十分必要。通过对引种的13种40份野生兜兰资源进行迁地栽培,并观测兜兰种质在迁移地的各种生长性状指标等,本研究利用灰色关联分析方法评价13种兜兰的迁地适应性,分析影响其迁地保护的关键因素。结果表明:(1)带叶兜兰、同色兜兰、长瓣兜兰、文山兜兰适应性较强,与理想种的关联度均在0.8以上;巨瓣兜兰、白花兜兰、小叶兜兰、紫纹兜兰、紫毛兜兰、硬叶兜兰适应性一般,与理想种的关联度在0.7~0.8之间;麻栗坡兜兰、杏黄兜兰、红旗兜兰适应性较差,与理想种的关联度均在0.6以下;(2)不同兜兰种类、同一种类不同产地兜兰种质的迁地生长适应性不同,来源地和栽培温度可能是影响其迁地保护的关键因子。  相似文献   

11.
We report 20 new species records for the Coleoptera fauna in New Brunswick, Canada, five of which are new records for the Maritime provinces, including one species that is new for Canada. One species of Kateretidae, Kateretes pusillus (Thunberg) is newly recorded for New Brunswick and the Maritime provinces. Stelidota octomaculata (Say), Phenolia grossa (Fabricius), andCryptarcha strigatula Parsons of the family Nitidulidae are added to the faunal list of New Brunswick; the latter species is new to the Maritime provinces. Two species of Cerylonidae, Philothermus glabriculus LeConte and Cerylon unicolor (Ziegler), are reported for the first time for New Brunswick. Philothermus glabriculus is new for the Maritime provinces. Two species of Endomychidae, Hadromychus chandleri Bousquet and Leschen and Danae testacea (Ziegler) are newly recorded for New Brunswick. Three species of Coccinelidae, Stethorus punctum punctum (LeConte), Naemia seriata seriata Melsheimer, and Macronaemia episcopalis (Kirby) are added to the provincial list. Macronaemia episcopalis (Kirby) is a species new to the Maritime provinces. Nine species of Latridiidae, Cartodere nodifer (Westwood), Dienerella ruficollis (Marsham), Enicmus aterrimus Motschulsky, Enicmus fictus Fall, Encimus histrio Jay and Tomlin, Lathridius minutus (Linnaeus), Stephostethus productus Rosenhauer, Corticaria elongata (Gyllenhal), and Corticarina longipennis (LeConte) are newly recorded for New Brunswick. Stephostehus productus is newly recorded from Canada. Collection and habitat data are presented for all these species.  相似文献   

12.
A review is presented of issues relevant to the definition, measurement, and classification of stimuli, situations, and environments. Problems such as the lack of adequate definitions of concepts, error and bias in measurement procedures, confusion between measurement of a concept and measurement of its behavioral effects, and the lack of agreement among alternative measures are emphasized. It is suggested that concepts be defined in terms of objective characteristics while allowing for the study of the transactional relationship between organism and environment. The work of the ethologists in defining stimuli while studying their relationship to different organismic states and situational contexts is emphasized in this regard. Following Brunswik, it is also suggested that wherever possible there be a representative sampling of variables in natural settings. Note from the editors: From time to time, Human Ecology will publish a review article. Our first in this series is a review by a psychologist of basic definitional and conceptual problems in environmental studies.This paper was prepared while the author was a Visiting Research Fellow at the Educational Testing Service. The support of ETS and my colleagues in the Division of Psychological Studies is gratefully acknowledged. The review was also supported in part by a grant from the Rutgers University Research Council.  相似文献   

13.
William Simkulet 《Bioethics》2019,33(9):1002-1011
Most serious contemporary opposition to abortion is grounded on the belief that human fetuses are members of the same moral category as beings like us, and that the loss of any such life is one of the worst possible losses. Substance view theorists oppose abortion for this reason: in their view beings like us are essentially rational substances with inherent moral worth, and those who perform induced abortion fail to recognize this moral worth. In a recent series of articles, Rob Lovering presents reductio‐style arguments against the substance view, in part arguing that it is inconsistent with our intuitions in rescue and spontaneous abortion cases. In a recent reply, Henrik Friberg‐Fernros argues that the substance view can evade these problematic implications because of a distinction between killing and letting die. According to this argument, the fetus’s right to life is a negative right not to be killed, not a positive right to be rescued, thus the anti‐abortion theorist who lets fetuses die acts acceptably. I argue this stance fails to recognize the inherent moral worth that the substance view contends fetuses possess. One who refrains from saving a person, or doesn’t care how many people she saves, cannot reasonably claim to value life. Furthermore, this stance is at odds with most contemporary anti‐abortion views that oppose induced abortions of both the killing and letting die variety.  相似文献   

14.
Piotrowska A  Bajguz A 《Phytochemistry》2011,72(17):2097-2112
Phytohormones, including auxins, abscisic acid, brassinosteroids, cytokinins, ethylene, gibberellins, and jasmonates, are involved in all aspects of plant growth, and developmental processes as well as environmental responses. However, our understanding of hormonal homeostasis is far from complete. Phytohormone conjugation is considered as a part of the mechanism to control cellular levels of these compounds. Active phytohormones are changed into multiple forms by acylation, esterification or glycosylation, for example. It seems that conjugated compounds could serve as pool of inactive phytohormones that can be converted to active forms by de-conjugation reactions. Some conjugates are thought to be temporary storage forms, from which free active hormones can be released after hydrolysis. It is also believed that conjugation serves functions, such as irreversible inactivation, transport, compartmentalization, and protection against degradation. The nature of abscisic acid, brassinosteroid, ethylene, gibberellin, and jasmonate conjugates is discussed.  相似文献   

15.
It is frequently claimed that green algae are intrinsically more productive, often by orders of magnitude, than higher plants commonly grown as crops for food. There is no firm evidence for this belief. On the contrary, there is much experience which shows that algae are not more but less productive. Under optimal conditions, all green organisms photosynthesize at the same rate in low light and, whilst commonly cultivated ‘sun’ species show some differences in rate in full light, these do not translate into widely different rates of accumulation of biomass. Accordingly, irrespective of crop, one acre of land, pond or bioreactor, can annually yield about enough biomass to fuel one motor vehicle or meet the calorific requirement of several people. This amount of biomass is not sufficient to make other than a very small contribution to our present road transport requirements and yet contributes significantly to global food shortages and rising prices. Reliable evidence also suggests that, if all of the inputs are taken into account, the net energy gain of liquid biofuels, derived either from algae or terrestrial crops, is either very modest or non-existent and will therefore bring about little or no sparing of carbon dioxide emissions.  相似文献   

16.
Oral cancer is one of the main causes of cancer-related deaths in South-Asian countries. There are very limited treatment options available for oral cancer. Research endeavors focused on discovery and development of novel therapies for oral cancer, is necessary to control the ever rising oral cancer related mortalities. We mined the large pool of compounds from the publicly available compound databases, to identify potential therapeutic compounds for oral cancer. Over 84 million compounds were screened for the possible anti-cancer activity by custom build SVM classifier. The molecular targets of the predicted anti-cancer compounds were mined from reliable sources like experimental bioassays studies associated with the compound, and from protein-compound interaction databases. Therapeutic compounds from DrugBank, and a list of natural anti-cancer compounds derived from literature mining of published studies, were used for building partial least squares regression model. The regression model thus built, was used for the estimation of oral cancer specific weights based on the molecular targets. These weights were used to compute scores for screening the predicted anti-cancer compounds for their potential to treat oral cancer. The list of potential compounds was annotated with corresponding physicochemical properties, cancer specific bioactivity evidences, and literature evidences. In all, 288 compounds with the potential to treat oral cancer were identified in the current study. The majority of the compounds in this list are natural products, which are well-tolerated and have minimal side-effects compared to the synthetic counterparts. Some of the potential therapeutic compounds identified in the current study are resveratrol, nimbolide, lovastatin, bortezomib, vorinostat, berberine, pterostilbene, deguelin, andrographolide, and colchicine.  相似文献   

17.
It is still not possible to provide an evidence-based answer to the question of whether regular exercise is essential for normal growth. It is also unclear whether very low levels of exercise result in growth deficits. Regular exposure to exercise is characterized by heterogeneity in responsiveness, with most individuals experiencing improvements in fitness traits but a significant proportion showing only very minor gains. Whether a sedentary mode of life during the growing years results in a permanent deficit in cardiorespiratory fitness or a diminished ability to respond favorably to regular exercise later in life remains to be investigated. Although several genes have been associated with fitness levels or response to regular exercise, the quality of the evidence is weak mainly because studies are statistically underpowered. The special case of the obese, sedentary child is discussed, and the importance of the "energy gap" in the excess weight gain during growth is highlighted. Obese, sedentary children have high blood pressure, dyslipidemia, elevated glycemia and type 2 diabetes, hepatic steatosis, respiratory problems, orthopedic complications, and other health disorders more frequently than normal weight, physically active children. The role of genetic differences in the inclination to be sedentary or physically active is reviewed. An understanding of the true role of genetic differences and regular exercise on the growth of children will require more elaborate paradigms incorporating not only DNA sequence variants and exercise exposure but also information on nutrition, programming, and epigenetic events during fetal life and early postnatal years.  相似文献   

18.
The Precautionary Principle is in sharp political focus today because (1) the nature of scientific uncertainty is changing and (2) there is increasing pressure to base governmental action on more “rational” schemes, such as cost-benefit analysis and quantitative risk assessment, the former being an embodiment of ‘rational choice theory’ promoted by the Chicago school of law and economics. The Precautionary Principle has been criticized as being both too vague and too arbitrary to form a basis for rational decision making. The assumption underlying this criticism is that any scheme not based on cost-benefit analysis and risk assessment is both irrational and without secure foundation in either science or economics. This paper contests that view and makes explicit the rational tenets of the Precautionary Principle within an analytical framework as rigorous as uncertainties permit, and one that mirrors democratic values embodied in regulatory, compensatory, and common law. Unlike other formulations that reject risk assessment, this paper argues that risk assessment can be used within the formalism of tradeoff analysis—a more appropriate alternative to traditional cost-benefit analysis and one that satisfies the need for well-grounded public policy decision making. This paper will argue that the precautionary approach is the most appropriate basis for policy, even when large uncertainties do not exist, especially where the fairness of the distributions of costs and benefits of hazardous activities and products are a concern. Furthermore, it will offer an approach to making decisions within an analytic framework, based on equity and justice, to replace the economic paradigm of utilitarian cost-benefit analysis.  相似文献   

19.
We report 19 new species records for the faunal list of Coleoptera in New Brunswick, Canada, six of which are new records for the Maritime provinces, and one of which is new Canadian record. We also provide the first recent records for five additional species in New Brunswick. One new species of Stenotrachelidae, Cephaloon ungulare LeConte, is added to the New Brunswick faunal list. Additional records are provided for Cephaloon lepturides Newman, as well the first recent record of Nematoplus collaris LeConte. Two species of Oedemeridae, Asclera puncticollis (Say) and Asclera ruficollis (Say), are newly reported for New Brunswick, and additional locality and bionomic data are provided for Calopus angustus LeConte and Ditylus caeruleus (Randall). The records of Ditylus caerulus are the first recent records for the province. Three species of Meloidae, Epicauta pestifera Werner, Lytta sayi LeConte, and Meloe augustcollis Say are reported the first time for New Brunswick; Epicauta pestifera is newly recorded in Canada. Lacconotus punctatus LeConte and the family Mycteridaeis newly recorded for New Brunswick. The first recent records of Borus unicolor Say (Boridae) are reported from the province. One new species of Pythidae, Pytho siedlitzi Blair, and the first recent records of Pytho niger Kirby are added to the faunal list of New Brunswick. Three species of Pyrochroidae are newly reported for the province, including Pedilus canaliculatus (LeConte) and Pedilus elegans (Hentz), which are new for the Maritime provinces. Five species of Anthicidae and the first recent record of Anthicus cervinus LaFerté-Sénectére are newly reported for New Brunswick. Anthicus melancholicus LaFerté-Sénectère, Sapintus pubescens (LaFerté-Sénectère), Notoxus bifasciatus (LeConte), and Stereopalpus rufipes Casey are new to the Maritime provinces faunal list. Ambyderus granularis (LeConte) is removed from the faunal list of the province. Three species of Aderidae, Vanonus huronicus Casey, Zonantes fasciatus (Melsheimer), and Zonantes pallidusWerner, are newly recorded for New Brunswick; Zonantes fasciatus and Vanonus huronicus are new for the Maritime provinces' faunal list. Collection data, bionomic data, and distribution maps are presented for all these species.  相似文献   

20.
This report attempts to formulate reference ranges of elemental concentrations for 15 trace elements in selected human tissues and body fluids. A set of samples consisting of whole blood, blood serum, urine, milk, liver, and hair were chosen and considered for 15 elements of biological significance: As, Cd, Co, Cr, Cu, F, Fe, I, Hg, Mn, Mo, Ni, Pb, Se, and Zn. The results represent wholly or partially data received from 40 countries of the global regions of Africa, Asia, Europe, North, South, and Central America, Australia, and New Zealand. This survey, even if qualitative, has been useful in demonstrating certain trends of trace-element scenarios around the world. It is of course recognized that both diet and environment exert a strong influence on the distribution pattern of several elements, such as As, Cd, Mn, Pb, Se, and Zn. A limited comparison of the available information on soil status of different countries reflected some interesting associations for elements, such as Mn and Zn. Importantly, this study revealed that only a few countries were in a position to identify a reasonable amount of data on samples requested for this project. Regretably, for a number of countries, any dependable data for even such essential elements as Cu, Fe, and Zn were not available. In view of the nutritional importance of many elements, the time is ripe for concerted efforts by intergovernmental agencies to initiate investigations or commission task forces/projects to generate reliable reference data for selected global regions, which sadly lack data of any kind at present.  相似文献   

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