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To search for new bioactive constituents from Pedicularis tricolor, a new xanthone named pedicutricone A (1)and a new iridoid named pedicutricoside A (2), along with fifteen known compounds, were isolated from the ethanol extracts of the whole plants of P. tricolor for the first time. Their structures were elucidated based on spectroscopic methods, including two-dimensional nuclear magnetic resonance analysis.  相似文献   

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三色马先蒿的化学成分研究   总被引:1,自引:0,他引:1  
从玄参科三色马先蒿(Pedicularis tricolor)全草的乙醇提取物中分离得到17个化合物,采用波谱方法鉴定了它们的结构。其中化合物1(2,3,5-tirmethoxy-4-hydroxy-xanthone)是一个新的[口山]酮,命名为三色马先蒿酮A(pedicutricone A);2(8α-hydroxyl-4-carboxyl-5βH,9βH-iridoid-1α-glycoside)是一个新的环烯醚萜苷,命名为三色马先蒿苷A(pedicutricoside A);化合物3-17为首次从该植物中分离得到。  相似文献   

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A study of a number of reproductive traits in two sympatric species of Pedicularis in northern Swedish Lapland, the subarctic-alpine P lapponica and the artic P hursuta , revealed that the life-history strategies of the two species differ profoundly High fruit set and low seed abortion rate, as m P hursuta , is common in arctic plants in late-thawing habitats and represents a case of extreme adversity selection rather than an indication of a ruderal life-history strategy Pedicularis lapponica , on the other hand, is a typical K-strategist (or stress-tolerator) requiring a longer period of growth for optimal reproduction Occuring at both low and high altitudes in the area, P lapponica tends to increase in self-compatibility with altitude, which is interpreted as an adaptation to lower pollinator visitation frequency in arctic environments The variation in length of the protruding part of the style in P lapponica is shown to be correlated with exposure to light Predispersal seed predation is severe m P lapponica at low altitudes, where the capsules are attacked by fly and moth larvae At high altitudes, a minor proportion of the capsules of P lapponica experience predation and only from flies, while P hursuta is completely unpredated  相似文献   

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A taxonomic revision ofCordylanthus subg.Hemistegia based on evidence from morphology, chromosome numbers, habitat, ecology, and geographic distribution is presented, recognizing four species and five subspecies. Three new combinations on the subspecific level are proposed. The first chromosome counts for subg.Hemistegia are reported with haploid numbers ofn = 14, 15, and 21. Each species is illustrated with line drawings showing habit and floral morphology; distribution maps indicate sites of known populations. The possible extinction ofC. mollis ssp.mollis andC. pamatus is discussed, and the urgent need for preservation of their saline and alkaline habitats is emphasized.  相似文献   

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云南马先蒿属植物的生物地理及物种多样性   总被引:2,自引:0,他引:2  
马先蒿属(Pedicularis)是被子植物中最大的属之一,在云南植物区系中占有重要地位。按照钟补求系统,该属植物在云南有151种分属于13个群72个系。马先蒿属在云南的地理分布体现了下列特点:(1)种类十分丰富,占整个属总种数的25%,占中国的42.6%。(2)包括了该属全部花冠类型,即无齿、有齿的原始类型各为24种、短管具喙的中间过渡类型87种,较进化的长管类型16种。(3)马先蒿属植物分布在云南的11个地理分布区域中,但该属植物在康藏高原区最为丰富,有108个种在本区有分布,占云南种数的71.5%;横断山植物区和东喜马拉雅植物区是本属的现代分布中心和多样性中心。(4)特有现象十分明显,其中8个系、52个种为云南特有,横断山和东喜马拉雅的特有种量为丰富,也是本属的特有中心。(5)民先蒿植物与邻近的四川(西南部)和西藏(东南部)在区系上联系密切,与缅甸和不丹有一定的联系。  相似文献   

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Abstract Pedicularis pulchella Pennell, endemic to sparsely vegetated areas of alpine tundra scree in southwestern Montana and northwestern Wyoming, was found to be roat-hemiparasitic and obligately dependent for its pollination upon bumblebees of three non-tundra species that forage primarily in an inverted position for pollen scraped from anthers concealed in the galea, This sternotribic pollination syndrome is considered related to the short (5–6mm) proboscides of pollinators on flowers with deep (12.4mm), nectariferous corolla tubes and favoring pollen as an insect attractant. Photographic and spectropholomelric analysis of the red-purple floral color included prominent blue corolla and ultraviolet calyx reflections corresponding to dominant colors of bumblebee visual spectra. Nectar analysis by thin-layer chromatography and refractomctry indicated, respectively, the presence of fructose and sucrose, and a sucrose-equivalent concentration of dissolved solids exceeding 50%; both coincide with the general pattern of the genus. Analysis of pollen from corbicular loads of P. pulchella pollinators indicated relatively low pollen-constancy of insects and substantial foraging association with Vaccinium in the montane-subalpine zone. By contrast, pollinators on P. cystopteridifolia and Phyllodoce glanduliflora in a diverse tundra plant community on rich alpine turf revealed broad pollinator spectra (7–8 species), high pollen-foraging constancy on Pedicularis, and high nectar-foraging frequency on Phyllodoce : The pollination ecology and endemism of Pedicularis pulchtella are interpreted in terms of resource sharing, spatial competition of plant species, and selective stress of the physical environment.  相似文献   

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Within recent years, Pedicularis verticilata L. have invaded in Bayanbulak grassland of XinJiang, and such invasion which is threatening grassland quality of livestock grazing in this region. Seed germinations of this species wereexamined based on six temperature treatments: constant temperature( treatment 1, 28℃; treatment 2, from17 to 20℃; treatment 3, from 9 to 16℃ ); alternative temperature ( treatment 4, 9.66, 10.21, 0.15 and - 0.83℃; treatment 5, 14.76, 20.9, 6.31 and 4.01℃; treatment 6, 26.17、29.58、5.19 and 0.75℃). The experiments results showed: 1) Germination rate were higher in alternative temperature than in constant temperature and the germination trend showed an uni-modal patterns; 2) Germination rate and germination index were lower in higher or lower temperature; 3) Germination rate and germination index under the alternatively changed temperatures (average temperature of the latter half on May in this region recorded as 14.76, 20.9, 6.31 and 4.01℃) was the highest, respectively 76.9% and 18.1. Therefore, it is suggested that, the late May might be the also the important time period to prevent this species from invading native grassland.  相似文献   

11.
温度对轮叶马先蒿种子发芽的影响   总被引:6,自引:0,他引:6  
为遏止轮叶马先蒿(Pedicularis verticilata L.)对新疆巴音布鲁克草原畜牧业的发展的威胁。开展了恒温和变温条件下轮叶马先蒿种子发芽试验,共设计了6个处理。结果表明:1)变温条件下的种子发芽率优于恒温,各处理每日种子发芽数目的变化均表现为先升高后下降。2)较高和较低温度下,发芽率和发芽指数均较低。3)在5月下半月变温(14.76,20.9,6.31和4.01℃)条件下,种子发芽率和发芽指数最高,分别为76.9%和18.1。因此,5月下半月是遏止本地入侵种轮叶马先蒿扩散的关键时期。  相似文献   

12.
Abstract Pedicularis howellii , endemic to the Siskiyou Mountains of California-Oregon, is a root hemiparasite obligately dependent upon bumblebee pollinators that remove pollen by vibration from its short-tubed, nectarless, rostrate flowers, which reflect visible and ultraviolet (360nm) light attractive to Bombus foragers. All six Bombus species in the study area pollinated the plant, but only on P. howellii and P. racemosa were B. mixtus workers the most abundant pollinators among the seven bumblebee-pollinated plants studied, including Delphinium decorum, Dodecatheon jeffreyi, Penstemon newberryi, P. shastensis, and Phacelia heterophylla. Analysis of corbicular pollen loads of Bombus pollinators indicated that pollen foragers on Pedicularis species were less pollen-constant than all other bumblebee pollinators. Although P. howellii and P. racemosa blooming periods overlapped slightly, phenological isolation of blooming periods of plants sharing the same pollinators was not evident. Chemical soil analysis of its habitat and quadrat analysis of the population structure of Pedicularis howellii indicated that the plant grows in a moderately fertile forest soil and is restricted to the edge of forest canopy openings where sunlight favors development of plants to the flowering stage. The endemism of P. howellii is related to a similar "edge effect" survival of P. furbishiae in a boreal forest riparian habitat previously studied.  相似文献   

13.
马先蒿属花冠形态的多样性与传粉式样的关系   总被引:8,自引:0,他引:8  
马先蒿属(Pediculais)是有花植物中花冠形态多样化最为集中的属。该属主要的传粉者是熊蜂属(Bormbus)昆虫;在北美,熊蜂和蜂鸟是马先蒿植物一些种类有效的传粉者;也发现壁蜂(Osmia)为其传粉。不同的传粉机制要求某一特定的取食式样储藏和释放花粉。本文讨论了花冠类型的进化趋势与传粉式样和花粉形态的关系。传粉者的选择压力是决定花冠多样化的重要因素之一;花冠类型与传粉者和传粉行为紧密相关。马先蒿植物和传粉者的相互依赖与其花冠类型、功能和物候互相适应,但花冠类型与花粉形态两者之间似乎没有明显的一一对应关系。通过北美、日本和喜马拉雅不同地理分布马先蒿种类的比较研究表明,具有相同花冠类型的种类有着相同的传粉方式,花冠形态与传粉式样存在紧密的协同进化关系。  相似文献   

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大王马先蒿云南五个居群遗传变异研究   总被引:1,自引:0,他引:1  
采用随机扩增多态DNA(RAPD)分子标记方法,对大王马先蒿(PedicularisrexL.)分布在云南中甸、丽江、大理、武定和昆明的5个居群(其中中甸居群有3个亚居群)的遗传多样性和遗传结构进行了研究。结果表明,大王马先蒿居群具有较高的遗传多样性,多态位点百分率P、Shannon表型多样性指数I和Nei的基因多样性指数h分别为82.0%、0.361和0.240,遗传多样性水平与居群的地理分布范围相关;大王马先蒿居群间的遗传变异较高,遗传变异主要发生在居群之间,而不是居群内部;居群间遗传分化系数Gst为0.747,遗传分化明显,居群间基因交流较少。居群间的遗传距离与居群间的相对地理距离具有一定的相关性。对云南西北部中甸居群的3个亚居群的遗传多样性分析表明,居群的遗传多样性水平与海拔高度有一定的相关性。居群间遗传变异较高可能是由于大王马先蒿为短命多年生植物,繁育系统为混交型,且自交占较大比例等原因造成的。  相似文献   

17.
The pollination biology of different populations of Pedicularis rex Clarke C B. was studied in Zhongdian of Northwest Yunnan and in Kunming of central Yunnan, respectively. Seed production depends exclusively upon pollination by bmnblebees ( Bombus Latr. ). The flowers are yellow, with short-tubed, erostrate and nectarless corolla. Two species of the bumblebee workers, Bombus friseanus Skorikov and B. lucorum L. foraged in an upright (nototribic) position for pollen. Meanwhile, Bombus friseanus workers also foraged in an inverted (stemotribic) position on P. rex, vibrating pollen from the anthers within the galea. This pollination syndrome was previously reported in the North American species, e.g.P, labradorica which has the same corolla-type with P. rex. A comparison of the corolla types and pollination syndrome on the species of Pediadaris in East Asia and North America indicates that such a pollination syndrome may be only found in the primitive corolla type of Pedicularis. In spite of the separation in the geological history, P. rex and P.labradorica share the same corolla type and pollination syndrome. Further study is needed to elucidate the biogeography of the Pedicularis.  相似文献   

18.
R. Neil Reese 《Brittonia》1984,36(1):63-66
Pedicularis contorta var.rubicunda, endemic to north-central Idaho and western Montana, is formally described and illustrated. Morphological and cytological comparisons are made with the two previously described varieties ofP. contorta. Specimens appearing morphologically intermediate between var.contorta and var.rubicunda are also examined.  相似文献   

19.
Abstract An introductory study of the pollination ecology of six Japanese species of Pedicularis conducted in 1982 and 1983 indicated a close parallel between characteristics of floral mechanisms in Japan and those previously investigated in North America. Floral color, floral form, total dissolved solids in floral nectar, and polinator behavior on flowers of Japanese species are similar to those of North American species. Blooming phenology of Japanese species also corresponds to the North American sequence of long-tongued, nectar-foraging queen bumblebees (Bombus Latr.) pollinating nectariferous , earlier-blooming species nototribically and short-tongued, pollen-foraging workers pollinating nectarless, rostrate flowers of later-blooming ones sternotribically. Electrofocus analysis of peroxidase systems in two Japanese species indicated considerable intrapopulational heterozygosity. Nectar component analysis of two transboreal species indicated intraspecific differences in kinds of sugars between widely disjunct Japanese and North American populations. A tentative conclusion is that the Japanese and North American Pedicularis floras have evolved in a parallel manner from Himalayan migrants, while their transboreal elements are in process of vicariant diversification.  相似文献   

20.
Abstract The pollination ecology of Pedicularis punctata was studied in the Pir Panjal Range of the Kashmir Himalaya in the summer of 1989. Its nectarless, rostrate, long-tubed flower was found to be pollinated exclusively by Bombus foragers vibrating pollen while the stigma contacted pollen in the pollinator's cervical crevice. Workers of Bombus tunicatus and B. flavothoracicus comprised 95% of its pollinators. Pollen-foraging fidelity of its pollinators was greatest where diversity of Bombus -pollinated plant species in three plant communities was least. Foragers on other plants carried virtually no Pedicularis pollen. P. punctata is a mid-season blooming species similar in its pollination syndrome to comparable species in other geographic regions. The enigmatic function of its long, nectarless corolla tube, even more exaggerated in other Asiatic species, requires further investigation.  相似文献   

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