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1.
Primula melanantha (Franch.) C. M. Hu, a taxon known from a single location in the south‐west of Sichuan Province of China and with a long and confused taxonomic history, is described and illustrated. Its relationships with other members of subsection Maximowiczii of section Crystallophlomis are discussed, new keys are provided, and factors relevant to its successful cultivation are described.  相似文献   

2.
Primula nghialoensis D. W. H. Rankin, a new species from Vietnam is described. It is assigned to the section Chartacea (Balf. f.) W.W.Sm., and its relationships with other members of this section, particularly P. petelotii, are discussed.  相似文献   

3.
The history and rediscovery of Primula ambita in Yunnan are described and the species is illustrated.  相似文献   

4.
Although pollination networks between plants and flower visitors are diverse and flexible, seed production of many plant species is restricted by pollen limitation. Obligate outcrossers often suffer from low pollinator activity or severe interspecific competition for pollinator acquisition among co-flowering species. This study focused on seasonal changes in plant–flower visitor linkages in an alpine ecosystem and examined whether and how this seasonality affected the seed-set of Primula modesta, a self-incompatible distylous herb having long-tubed flowers. First, we recorded the linkages between plants and flower visitors along the snowmelt gradient. Then, pollination experiment was conducted to estimate the degree of pollen limitation over the course of flowering season of P. modesta. Flower visitors were classified by their tongue length based on the morphological matching with P. modesta flowers. As the season progressed, plant–visitor linkages became more diverse and generalized, and the visitation frequency to P. modesta flowers increased. In the later part of the season, however, the seed set of P. modesta was significantly reduced due to severe pollen limitation, presumably because of increased competition for long-tongued pollinators among co-flowering species. The present study revealed that pollinator availability for specialist species may be restricted even when plant–visitor linkages are diverse and generalized as a whole. In the case of P. modesta, morphological matching and competition for pollinators might be the main factors explaining this discrepancy.  相似文献   

5.
Primula jiugongshanensis J. W. Shao, a new species from Mt Jiugongshan in Hubei Province, China, is described and illustrated. This species is a biennial glabrous herb with pinnately compound leaves, and affiliated to P. sect. Ranunculoides C. M. Hu. It is distinguished from other species of the section by outer simple leaves ovate, flowers distylous, corolla lobe apex conspicuously emarginate, and lack of bulblets. Molecular phylogenetic analysis of nrDNA internal transcribed spacer sequences (ITS) was conducted and the results also supported the recognition of P. jiugongshanensis as a new species. The species is known from only three separated unprotected populations and is categorized as ‘Endangered’ (EN).  相似文献   

6.
The hexaploid herbaceous species Primula glaucescens Moretti and Primula spectabilis Tratt. (2n = 6x = 66) are two endemics of the Italian Pre-Alps protected by national and international laws. In order to plan conservation strategies for natural populations and to study the influence of the latest glaciation on them we developed a set of microsatellites markers for the endangered Primula species: ten primer pairs allowed analysis of polymorphic disomic loci in P. glaucescens samples and seven of them also amplified polymorphic disomic markers in P. spectabilis. Kirsten Wolff and Giorgio Binelli contributed equally to the paper  相似文献   

7.
Major geological processes have shaped biogeographical patterns of riverine biota. The Edwards Plateau of central Texas, USA, exhibits unique aquatic communities and endemism, including several species of freshwater mussels. Lampsilis bracteata (Gould, 1855) is endemic to the Edwards Plateau region; however, its phylogenetic relationship with other species in the Gulf coastal rivers and Mississippi River basin is unknown. We evaluated phylogenetic relationships, shell morphologies and soft anatomy characters of L. bracteata and a closely related congener, Lampsilis hydiana (Lea, 1838) throughout their ranges. Our results showed the presence of an undescribed species: Lampsilis bergmanni sp.n. Lampsilis bracteata and L. bergmanni sp.n. share similar shell morphologies and soft anatomy characters; however, they are genetically distinct. Geological processes, such as faulting and sea-level changes during the Miocene to Pliocene, are likely to have facilitated diversification of Lampsilis species, resulting in isolation of L. bracteata on the Edwards Plateau and diversification between L. bergmanni sp.n. and L. hydiana. We conclude that L. bracteata range is restricted to the Colorado River basin, whereas L. bergmanni sp.n. occurs only in upstream reaches of the Guadalupe River basin. Conservation actions are warranted for both species due to their restricted distributions and potential anthropogenic threats.  相似文献   

8.
Abstract

Notes on the polystelic structure in Primula glaucescens Moretti and Primula longobarda Porta. — The rhizome anatomy of Primula glaucescens Moretti and Primula longobarda Porta (two species endemic to Lombardy) have been studied. It has been found that the polystelic structure is present in the rhizome of both species, but with some differences. The taxa show a difference in the number and size of steles and amount of sclerenchymatic tissue within the single stele.

Our investigations confirm the necessity to separate in a specific rank Primula glaucescens Moretti from Primula longobarda Porta, as already proposed by Arietti and Crescini (1976).  相似文献   

9.
Severe attack by the fungal pathogen Synchytrium decipiens frequently occurs in natural populations of the annual plant Amphicarpaea bracteata (Leguminosae) in eastern North America. Field transplant experiments indicate that there is significant population differentiation in the plant-fungus association over distances of 1 km or greater: plants transplanted back into their population of origin become heavily infected, while foreign plants from populations 1 or 100 km away experience little or no infection, even though these foreign plants are subject to heavy fungal attack in their native populations. To investigate the fine structure of population differentiation, progeny of A. bracteata plants collected at six sites at 30 m intervals along a transect were inoculated with a single strain of S. decipiens in a controlled environment. Fungal lesions were initiated in all 36 plant progeny groups tested, yet there was highly significant, 5-fold variation among plants from different sites in the mean number of fungal lesions developing per plant. In addition, all fungal lesions aborted without maturing spores on all plants from one site on the transect. Fungal lesion abortion rates averaged only 9% on plants from the other five sites. Such local population differentiation in plant-pathogen compatibility may be related to A. bracteata's high degree of self-pollination. Limited long-distance recombination in A. bracteata due to self-pollination and spatially restricted pollen flow may be a major factor preventing the evolution of increased plant resistance to fungal attack.  相似文献   

10.
刘林  张良英  程贵兰  何丹  张力飞  孟凡丽 《广西植物》2022,42(10):1675-1683
采用扫描电镜法,观察和比较了西藏色季拉山10种报春花的花粉形态特征,同时进行聚类分析,以期为该属植物分类提供孢粉学证据,并进一步为西藏报春花属植物杂交育种及种质资源的利用提供参考。结果表明:(1)供试10种报春花属植物的花粉形状为扁球形、近球形,其中,工布报春(Primula kongboensis)的花粉粒最小,暗紫脆蒴报春(P.calderiana)的花粉粒最大,西藏报春(P.tibetica)为多沟型花粉,其余报春花的花粉一般具3孔沟,大部分孔沟在极区汇合形成复合沟。(2)花粉外壁纹饰大多为穴状或网状,其中,中甸灯台报春(P.chungensis)和西藏报春为网状纹饰中的粗网状类型。(3)虽然基于花粉形态的聚类分析与植物学分类表现出一定的一致性,但粉报春组的西藏报春和工布报春则由于在孢粉学特征上具有明显差异,因此保持了相对较远的亲缘关系。该研究初步认为,色季拉山10种报春花粉形态存在种间差异,研究结果可为植物分类提供一定的参考依据。然而,在进行分类时,仍然需要结合形态学特征、分子生物学等方面综合考虑。  相似文献   

11.
卢元  黎斌  张莹  李思锋 《西北植物学报》2015,35(5):1066-1068
报道了陕西省植物分布新记录2种1亚种。新记录种分别是梨序楼梯草(Elatostema ficoides Wedd.)和粉叶栒子(Cotoneaster glaucophyllus Franch.),新记录亚种是藤山柳原亚种[Clematoclethra scandens(Franch.)Maxim.subsp.scandens]。  相似文献   

12.
为探索适生木本植物对热带珊瑚岛极端环境的适应策略,从海南文昌移栽夹竹桃(Nerium indicum)、黄金香柳(Melaleuca bracteata)、桑树(Morus alba)和银叶树(Heritiera littoralis)到热带珊瑚岛,对两地植物的叶片形态解剖学特性和抗性生理特征进行比较研究。结果表明,与文昌相比,热带珊瑚岛桑树的比叶面积显著增高;夹竹桃的栅栏海绵组织比无显著差异,而其他3种植物则显著降低;夹竹桃和桑树的叶绿素含量显著增高,黄金香柳和银叶树则显著降低;桑树的总抗氧化能力显著降低,其他3种植物则显著升高;夹竹桃的脯氨酸含量显著降低,其他3种植物则显著升高。因此,4种木本植物为适应热带珊瑚岛生境,夹竹桃和桑树呈现出“提高碳同化潜力-承受更高伤害”策略;而黄金香柳和银叶树呈现为“提高抵抗力-降低碳同化潜力”策略。  相似文献   

13.
Tabernaemontana alba and Tabernaemontana arborea are Apocynaceae species used in Mexican traditional medicine for which little phytochemical information exists. In this study, preliminary gas chromatography/mass spectrometry analyses of different organs obtained from wild plants of both species identified a total of 10 monoterpenoid indole alkaloids (MIAs) and one simple indole alkaloid, nine of which were reported for the first time in these species. Furthermore, callus cultures were established from T. alba leaf explants and regeneration of whole plants was accomplished via somatic embryogenesis. The anti‐addictive MIAs ibogaine and voacangine were then quantified by gas chromatography with flame ionization detection in wild plants of both species, as well as greenhouse‐grown plants, in vitro‐grown plantlets and embryogenic callus of T. alba. Ibogaine and voacangine were present in most samples taken from the whole plants of both species, with stem and root barks showing the highest concentrations. No alkaloids were detected in callus samples. It was concluded that T. alba and T. arborea are potentially viable sources of ibogaine and voacangine, and that these MIAs can be produced through somatic embryogenesis and whole plant regeneration of T. alba. Approaches to increase MIA yields in whole plants and to achieve alkaloid production directly in cell cultures are discussed.  相似文献   

14.
一种报春花的新命名   总被引:1,自引:0,他引:1  
由于种加词相重,陈封怀、胡启明(1990)发表的新种Pimula exscapa Chen et C.M.Hu(holotype,S.G.Xu 3568 KUN)应是Primula exscapa Hegetschw.,FL Schw.195.1838的晚出同名,应给予重新命名.  相似文献   

15.
五种野生观赏报春花引种驯化初报   总被引:13,自引:0,他引:13  
报道了采自云南西北部的5种野生报春(灰岩皱叶报春Primula forrestii Franck,海仙花P,poissonii Franck,橘红灯台报春P.bulleyanan Forr.,偏花报春P.secundiflora Franch和钟花报春P.sikkimensis Hook)的引种驯化研究。将采自不同地方,不同气候以及不同生态环境下的种子,通过在不同控制条件下包括基质、温度、光照等“从种子到种子”整个过程的实验观察,得出结果如下:(1)虽然每个种的种子在不同的基质中萌发率参差不齐,但所有种子在昆明栽培条件下都有高的萌发适应性。(2)虽然它们的开花时间不同(海仙花和偏花报春除外),但所有从播种获得的植株要10—16个月才能开花,与野生报春相比栽培的报春花花期提前2—3个月,灰岩皱叶报春还出现了重瓣花。(3)苗圃的报春花结实率比在野生状态下的低,人工授粉后座果率有所提高。  相似文献   

16.
Li AR  Guan KY 《Mycorrhiza》2007,17(2):103-109
Colonization of mycorrhizal and root endophytic fungi in 14 Pedicularis species from northwest of Yunnan Province, southwest China, was examined. These species included: Pedicularis gracilis Wall., Pedicularis longipes Maxim., Pedicularis axillaris Franch., Pedicularis cephalantha Franch., Pedicularis tenuisecta Franch., Pedicularis tapaoensis Tsoong, Pedicularis likiangensis Franch., Pedicularis dichotoma Bonati, Pedicularis yui Li, Pedicularis rhinanthoides Schrenk, Pedicularis rex C.B. Clarke, Pedicularis longiflora Rudolph., Pedicularis siphonantha Don, and Pedicularis oxycarpa Franch., among which nine are endemic to China (one to Yunnan). Three types of potentially beneficial fungi associated with roots of these species were observed, namely, arbuscular mycorrhizal fungi, ectomycorrhizal fungi, and dark septate endophytic fungi (DSEF), with DSEF as the most common colonizers. An unexpected high colonization level was detected in this hemiparasitic genus. Of the 19 sampling sites examined, 10 gave colonization frequency of above 50% and 6 showed a colonization index of above 50. Heavy colonization suggested a significant ecological role of these fungi and their potential to be applied to successful cultivation of these intractable plants.  相似文献   

17.
Local populations of the plant Amphicarpaea bracteata often contain genetically divergent lineages that differ strongly in disease resistance toward the specialist pathogen Synchytrium decipiens. In one population, lineages with disease resistance were observed to significantly decrease in frequency over a two-year period, despite the continued presence of pathogens. Extensive self-pollination in A. bracteata restricts the opportunity for recombination of alleles affecting separate traits, resulting in strong correlations between disease resistance and other ecologically important characters, including plant morphology, phenology, and patterns of reproductive allocation. Natural selection on these correlated characters may thus cause nonadaptive changes in disease resistance. These results imply that A. bracteata's mating system is a basic constraint interfering with its adaptation to pathogen attack.  相似文献   

18.
The cultivated strawberry is one of the youngest domesticated plants, developed in France in the 1700s from chance hybridization between two western hemisphere octoploid species. However, little is known about the evolution of the species that gave rise to this important fruit crop. Phylogenetic analysis of chloroplast genome sequences of 21 Fragaria species and subspecies resolves the western North American diploid F. vesca subsp. bracteata as sister to the clade of octoploid/decaploid species. No extant tetraploids or hexaploids are directly involved in the maternal ancestry of the octoploids.There is strong geographic segregation of chloroplast haplotypes in subsp. bracteata, and the gynodioecious Pacific Coast populations are implicated as both the maternal lineage and the source of male-sterility in the octoploid strawberries. Analysis of sexual system evolution in Fragaria provides evidence that the loss of male and female function can follow polyploidization, but does not seem to be associated with loss of self-incompatibility following genome doubling. Character-state mapping provided insight into sexual system evolution and its association with loss of self-incompatibility and genome doubling/merger. Fragaria attained its circumboreal and amphitropical distribution within the past one to four million years and the rise of the octoploid clade is dated at 0.372–2.05 million years ago.  相似文献   

19.
A new species of Primulaceae, Primula persimilis G. Hao, C.M. Hu & Y. Xu, from Sichuan, China, is described and illustrated. In general morphology it is allied to the species of P. sect. Monocarpicae, characterized by the presence of multi‐cellular hairs, the distinctly petiolate leaves, a campanulate calyx, and a globose or cylindrical capsule with valvate dehiscence. The new species superficially resembles P. tsiangii W.W. Smith, but can be distinguished by its white flowers, longer calyx lobes, and cylindrical capsules.  相似文献   

20.

The spread of non-native species results in novel and often unexpected assemblages. Using stable isotopes, we disentangled the trophic relationships between three invasive crayfish species at two sites of a small thermal tributary of the Barát stream, Hungary. We studied Procambarus virginalis and Faxonius limosus living in sympatry in the upper section of this thermal tributary, and then an assemblage in a lower section also containing P. clarkii. The two species in the upper section largely shared trophic niches, although P. virginalis was more carnivorous than F. limosus, which fed more on detritus and aquatic plants. In the lower section, P. clarkii had a distinctive trophic niche, being more carnivorous than the other species and also preying on other crayfish and fish. The trophic niches of the other two species shifted slightly, being narrower and more overlapping in the presence of P. clarkii. It seems that the presence of P. clarkii affects the feeding habits and trophic niches of the other two crayfish. Our results also indicate that the species have somewhat distinctive feeding niches, which suggests that the ecosystem effects of these species are likely to be at least partially additive in the shared localities.

  相似文献   

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