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1.
报道了中国锦葵科(Malvaceae)一新记录属——沙稔属(Sidastrum Baker f.),小花沙稔[Sidastrum micranthum (A. St.-Hil.)Fryxell]首次在广东发现。 相似文献
2.
A new genus of Violaceae is described from Brazil.Hybanthopsis Paula-Souza, with a single species (H. bahiensis Paula-Souza), is endemic to caatingas of Bahia, Brazil, and is morphologically most similar toHybanthus, from which it differs by the fruit morphology and especially its peculiar seeds.
Um novo gênero brasileiro de Violaceae é descrito.Hybanthopsis Paula-Souza, com uma única espécie (H. bahiensis Paula-Souza), é endêmico de caatingas do Estado da Bahia, e é morfologicamente mais similar aHybanthus, do qual difere pela morfologia do fruto e especialmente por suas sementes peculiares.相似文献
3.
J. F. B. Pastore 《Kew Bulletin》2009,64(4):709-712
The results of this study show that Polygala communis A. St.-Hil. & Moq., P. lindenii Chodat, P. diversa S. F. Blake, and P. urbanii Chodat are synonyms of P. monninoides Kunth. The identity of Polygala monninoides Kunth is discussed. An epitype for P. monninoides is designated and an illustration and comments about its distribution are provided. 相似文献
4.
Eritrichium nanum 《Flora》2004,199(5):398-408
In 14 permanent plots at four distant sites in the European Alps life tables, cohorts and recruitment of Eritrichium nanum were studied during a period of 5 resp. 6 years. The germination rates were tested in the Botanical Institute of the University of Basel and besides the life tables of the plots at natural habitats we followed the early stages of development in pot cultures at the University Botanical Garden in Basel. Most of the seedlings of E. nanum emerged in spring, in the pot cultures as well as under natural conditions, a behavior which confirms general findings. But the germination rates (0–30%) were markedly low. The pot cultures show that some seeds are after 4 or 5 years still viable. Premature flowering in the second summer is a rather common behavior of E. nanum seedlings, which happened in all the cohorts observed during five years, partly up to 20% of the total of living plants in the corresponding plots. It is evident that life expectancy of E. nanum plants increase rapidly with rising size, to such a degree that cushions of only 10–20 cm2 surface have a survival chance of more than 70%, those of 20–30 cm2 even of more than 95% during a period of 5 years. But it has to be mentioned that juvenile plants are not growing parallel to their lifetime, many of them persist during several years in the size categories I/II (0–5 cm2), while others suddenly arise from category I to III (–10 cm2) or even IV (–20 cm2), what is mostly caused by joining, a specific type of safe site strategy. Though not obligatory, juvenile plants growing close together, often add their sizes to form one larger cushion, which was found to be particularly advantageous for recruitment. This is obviously a primary strategy of E. nanum and favors, especially on bare ground, the survival of its descendants which was found higher than expected (average of 26% after 5 years’ growth at natural habitats). Focusing on the whole life cycle of E. nanum, the present studies show constraints in pollination, a small seed production and low germination rates to be well compensated by the high survivorship and successful recruitment of the seedlings. 相似文献
5.
Résumé Les auteurs ont découvert, dans le sol roumain, la large présence duMicrosporon nanum —Fuentes 1956. Ils font mention de certaines particularités des souches isolées du sol, à savoir la forme très variable des macroconidies dont la majorité sont dépourvues de septa, l'absence des microconidies, l'absence du pléomorphisme et le faible pouvoir pathogène envers l'homme et les animaux d'expérience. Toutefois ils ont réussi à inoculer le champignon, avec résultat positif, à l'homme et au cobaye. La disposition selon le type microsporique, du parasite dans le poils du cobaye atteint de mycose expérimentale, de même que la photoluminescence jaune-verdâtre, caractéristique de ses poils, ont permis aux auteurs de considérer leMicrosporon nanum comme un vraiMicrosporon, distinct duMicrosporon gypseum. La large présence dans le sol et le faible pouvoir pathogène prouve, selon les auteurs, que leM. nanum est un saprophyte du sol.
(Travail du Centre Dermato-Vénéréologique de Bucarest. Directeur:St. G. Nicolau, membre de l'Académie de la République Populaire Roumaine) 相似文献
Summary The authors were able to recoverMicrosporon nanum —Fuentes 1956 from numerous roumanian soil samples. They pointed out some peculiarities of the soil isolates, viz. the very diverse forms of the macroconidia, the lack of pleomorphic change and the low degree of pathogenicity to man and the experiment animals. Nevertheless, they were able to inoculate, with positive result, one isolate in man and Guinea pig. The microsporical type of invasion, the parasite showed in the infected hairs of the Guinea pig, inoculated with one of the strains, so as their characteristic yellow-green fluorescence in the Wood's light, suggests thatMicrosporon nanum is a realMicrosporon, quite distinct fromMicrosporon gypseum. The ubiquitous presence in soil and the low degree of pathogenicity evidences, in the authors opinion, the geophilic and saprophytic nature ofMicrosporon nanum.
(Travail du Centre Dermato-Vénéréologique de Bucarest. Directeur:St. G. Nicolau, membre de l'Académie de la République Populaire Roumaine) 相似文献
6.
U. Albino D. P. Saridakis M. C. Ferreira M. Hungria P. Vinuesa G. Andrade 《Plant and Soil》2006,287(1-2):199-207
Drosera villosa var. villosa A. St.-Hil is a carnivorous plant that grows in Brazilian flooded soils very poor on nutrients, including low levels of N. Under these conditions, the plant shows vigorous growth, low root number, low number of captured prey (less than 50%) and a great assemblage of bacteria associated with the roots and leaves that grow in N-free medium. These preliminary results have led us to investigate the number of colony forming units (log CFU) in the roots (rhizosphere and endorhizosphere) and leaves (phyllosphere and endophyllosphere) of D. villosa var. villosa by the tenfold serial dilution technique in two N-free culture media. The results showed that the phyllosphere had 6.65 log CFU g dry leaf−1 and the rhizosphere 6.47 log CFU g dry soil−1, with the lowest value detected in the endophyllosphere (4.39 log CFU g dry leaf−1). Sixty-three different bacteria morphotypes were isolated from the surface and interior of the roots and leaves and the amplification of the DNA with specific primers detected the nifH gene in 34 of those strains. The DNAs of the 34 strains were compared by the BOX-PCR technique and a great diversity was observed, with the bacteria clustering at a final level of similarity of only 12%. The strains were also submitted to the partial sequencing of the 16S rRNA gene and several genera of N2-fixing bacteria were detected, including Bacillus, Burkholderia, Methylobacterium, Paenibacillus, Pseudomonas and Sphingomonas. 相似文献
7.
Wirth LR Waser NM Graf R Gugerli F Landergott U Erhardt A Linder HP Holderegger R 《Oecologia》2011,167(2):427-434
Plants flowering together may influence each other’s pollination and fecundity over a range of physical distances. Their effects
on one another can be competitive, neutral, or facilitative. We manipulated the floral neighborhood of the high-alpine cushion
plant Eritrichium nanum in the Swiss Alps and measured the effects of co-flowering neighbors on both the number of seeds produced and the degree
of inbreeding and outbreeding in the offspring, as deduced from nuclear microsatellite markers. Seed set of E. nanum did not vary significantly with the presence or absence of two Saxifraga species growing as near neighbors, but it was higher in E. nanum cushions growing at low conspecific density than in those growing at high density. In addition, floral neighborhood had no
detectable effect on the degree of selfing of E. nanum, but seeds from cushions growing at low conspecific density were more highly outbred than seeds from cushions at high density.
Thus, there was no evidence of either competition or facilitation between E. nanum and Saxifraga spp. as mediated by pollinators at the spatial scale of our experimental manipulation. In contrast, the greater fecundity
of E. nanum cushions at low density was consistent with reduced intraspecific competition for pollinators and might also represent a
beneficial effect of highly outbred seeds as brought about by more long-distance pollinator flights under low-density conditions. 相似文献
8.
Contrasting modes of light acclimation in two species of the rainforest understory 总被引:10,自引:0,他引:10
In tropical rainforests, the increased light associated with the formation of treefall gaps can have a critical impact on
the growth and survivorship of understory plants. Here we examine both leaf-level and whole-plant responses to simulated light
gap formation by two common shade-tolerant shrubs, Hybanthus prunifolius and Ouratea lucens. The species were chosen because they differed in leaf lifespans, a trait that has been correlated with a number of leaf-
and plant-level processes. Ouratea leaves typically live about 5 years, while Hybanthus leaves live less than 1 year. Potted plants were placed in the understory shade for 2 years before transfer to a light gap.
After 2 days in high light, leaves of both species showed substantial photoinhibition, including reduced CO2 fixation, F
v/F
m and light use efficiency, although photoinhibition was most severe in Hybanthus. After 17 days in high light, leaves of both species were no longer photoinhibited. In response to increased light, Ouratea made very few new leaves, but retained most of its old leaves which increased photosynthetic capacity by 50%. Within a few
weeks of transfer to high light, Hybanthus had dropped nearly all of its shade leaves and made new leaves that had a 2.5-fold greater light-saturated photosynthetic
rate. At 80 days after transfer, the number of new leaves was 4.9-fold the initial leaf number. After 80 days in high light, Hybanthus had approximately tenfold greater productivity than Ouratea when leaf area, photosynthetic capacity, and leaf dark respiration rate were all taken into account. Although both species
are considered shade tolerant, we found that their growth responses were quite different following transfer from low to high
light. The short-lived Hybanthus leaves were quickly dropped, and a new canopy of sun leaves was produced. In contrast, Ouratea showed little growth response at the whole-plant level, but a greater ability to tolerate light stress and acclimate at the
leaf level. These differences are consistent with predictions based on leaf lifespan and are discussed within the context
of other traits associated with shade-tolerant syndromes.
Received: 25 March 1999 / Accepted: 16 August 1999 相似文献
9.
Fourier transform infrared characterization of the Middle Devonian non‐vascular plant Spongiophyton
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Spectroscopy information (functional groups and semiquantitative data) by Fourier transform infrared (FTIR) spectroscopy of Spongiophyton Kräusel emend. Chaloner et al. is reported for the first time, in an attempt to identify spectroscopic patterns that would differentiate species of these taxa. A total of 33 specimens identified as S. lenticularis, S. nanum and S. minutissimum and preserved as compressions were analysed. They come from the same fossiliferous horizon of one outcrop situated in the uppermost Middle Devonian São Domingos Formation of the Paraná Basin in southern Brazil. The results reveal that functional groups in the 3000–2800 and 1800–700 cm?1 wavenumber regions are present in all specimens. Infrared‐derived ratios (CH2/CH3, Al/Ox, Ox1/Ox2, C=O cont., C=C cont., Al2 and Ar/Al) and types of kerogen led to a comparison of the morphological characteristics of the studied material and indicate that compressions of S. lenticularis, S. nanum and S. minutissimum contain different organic compounds. S. nanum and S. minutissimum show higher oxidation and lower aromaticity of its organic matter than S. lenticularis. Additionally, S. lenticularis shows low A‐factor values, suggesting a composition similar to type III kerogen, while S. nanum and S. minutissimum showed intermediate to high A‐factor values, suggesting a composition similar to type II kerogen. In conclusion, the chemical‐analytical techniques and statistical analysis (using PCA technique) reveal a closer taxonomic relationship between S. nanum and S. minutissimum than either has with S. lenticularis, supporting their taxonomic separation, previously proposed in the literature on the basis of morphological features. Lastly, the chemical signatures support the hypothesis that links these enigmatic fossils to a type of lichen or other early inland plant. 相似文献
10.
R. Fenner M. Sortino S.M. Kuze Rates R. DallAgnol A. Ferraz A.P. Bernardi D. Albring C. Nr G. von Poser E. Schapoval S. Zacchino 《Phytomedicine》2005,12(3):236-240
Crude methanolic extracts and fractions from the aerial parts of seven species of Hypericum (H. caprifoliatum Cham. and Schltdl., H. carinatum Griseb., H. connatum Lam., H. ternum A. St.-Hil., H. myrianthum Cham. and Schltdl., H. piriai Arechav. and H. polyanthemum Klotzsch ex Reichardt) growing in southern Brazil were analyzed for their in vitro antifungal activity against a panel of standardized and clinical opportunistic pathogenic yeasts and filamentous fungi, including dermatophytes, by the agar dilution method. Chloroform and hexane extracts of H. ternum showed the greatest activity among extracts tested. 相似文献
11.
Summary
Microsporum nanum
Fuentes was isolated from a ringworm lesion on the back of the hand of a seven year old Alberta schoolgirl. This is the first record ofM. nanum in Canada and the first infection reported from the northern part of the temperate zone. 相似文献
12.
Two new species of Rutaceae, Conchocarpus hamadryadicus Pirani & Kallunki and C. minutiflorus Groppo & Pirani are described and illustrated. Both are known so far only from small remnants of forests, the former in the
caatinga dominium in Bahia, the latter in moist forests near Santa Teresa, Espírito Santo, Brazil. Their main diagnostic features
are delineated, and their relationships to other species of Conchocarpus are discussed. Because Rauia racemosa Nees & Mart. can no longer be recognised as a synonym of Conchocarpus fontanesianus (A. St.-Hil.) Kallunki & Pirani, a new combination, C. racemosus (Nees & Mart.) Kallunki & Pirani, is provided, with comments. 相似文献
13.
Flower development, pollination and breeding system of the high alpine cushion plant, Eritrichium nanum (Boraginaceae), were investigated in nine populations from the European Alps at altitudes of 2700 m–3200 m. Peak flowering
period lasts longer than a month, from mid-June to the end of July. In contrast to statements in the literature that flowers
are protogynous and nutlets remain in their calyx until spring we found a distinct protandry and nutlets being dispersed before
mid-September. Various insects from 12 families, but mostly Diptera, frequently visited E. nanum flowers, with flies from the families Anthomyiidae and Muscidae being the predominant visitors. Under optimal conditions
(max. solar radiation, min. wind force), visitation rates of 200 simultaneously observed flowers reached 32.5–46.7 insects
per hour, i.e. 0.16–0.24 insects per flower per hour. However, the commonly observed Anthomyiidae and Muscidae clearly preferred
the white-yellowish flowers of Saxifraga exarata and Saxifraga bryoides which are abundant at E. nanum sites and which are certainly also pollinated by species of these two fly families. The flowers of these Saxifraga species offer plenty of nectar and may compete for pollinators with E. nanum, when they are flowering in its proximity. However, various other insects like Pontia callidice and Psodos sp. (Lepidoptera) as well as Andrena sp. (Hymenoptera) and especially Eristalis tenax and closely related hoverflies showed a higher degree of flower constancy to E. nanum, often flying from a blue Eritrichium cushion to the next and hence causing outcrossing. The five fornices of E. nanum flowers which obstruct the tube containing stamens and nectar, are a feature which differs distinctly from the syndrome of
fly-pollinated flowers with easily accessible nectar. Consequently pollination by flies in E. nanum seems to be caused mainly by the unfavorable ecological conditions at high altitudes, where flies are the most frequent insects.
Bagging experiments showed that outcrossing and geitonogamy are the prevailing pollination modes, and autogamy, although possible,
plays only a minor role.
Received February 13, 2001 Accepted November 23, 2001 相似文献
14.
Paula Piekarski-Barchik Suelen Ávila Sila M. R. Ferreira Nayana C. S. Santos Francisco A. Marques Mayara P. dos Santos Marco T. Grassi Marilis D. Miguel Obdulio G. Miguel 《化学与生物多样性》2021,18(8):e2100257
Allophylus edulis (A. St.-Hil., A. Juss. & Cambess.) Radlk. (Sapindaceae) is an edible plant from the South American biodiversity that is a potential source of bioactive compounds. The mineral content and antioxidant activity of Allophylus edulis leaves were investigated, as well as the composition and the antioxidant activity of the essential oil. The mineral content was determined by ICP – OES and the antioxidant assays were assessed by ABTS, DPPH and FRAP. The essential oil was obtained by hydrodistillation and analyzed by GC/MS. Calcium, potassium, phosphorus, sulfur, and magnesium were the main minerals found in A. edulis leaves. Of the toxic metals that were present, a low level of aluminum was detected. The essential oil of A. edulis has (E)-nerolidol as major compound and both, the leaves, and the essential oil isolated from the leaves have antioxidant potential. These findings could provide a framework for developing new food and non-food products with A. edulis leaves. 相似文献
15.
Acácio R. A. Moraes Karen C. Camargo Maria O. M. Simões Vany P. Ferraz Márcio T. Pereira Fernanda C. G. Evangelista Adriano P. Sabino Lucienir Pains Duarte Antônio F. C. Alcântara Grasiely F. de Sousa 《化学与生物多样性》2021,18(6):e2100094
Magonia pubescens A. St.-Hil. is a Brazilian species often used in ethnopharmacology for wound and pain healing and seborrhea treatment. For the first time, essential oils (EOs) obtained from M. pubescens inflorescences were studied. The plant materials (Montes Claros, Brazil, 2018) were submitted to different gamma-radiation doses and their chemical compositions were analyzed by GC/MS and GC-FID. The cytotoxic activity of the EOs was evaluated against K562 and MDA-MB-231 cancer cell lines. A total of 30 components were identified, being 24 compounds detected for the first time in M. pubescens. The main obtained components were hotrienol (35.9 %), cis-linalool oxide (17.0 %) and trans-linalool oxide (10.2 %). The chemical composition of the EO was slightly affected by the applied radiation doses. Irradiated and non-irradiated EOs showed cytotoxic activity against both cell lines and the non-irradiated EO sample was the most active against the K562 cell lines (IC50=22.10±1.98). 相似文献
16.
17.
To understand the differences in the spawning sites among Cyprininae fishes in Lake Biwa, we conducted periodic sampling of
larvae and juveniles at three sites (irrigation ditch, St. 1; river, St. 2; and satellite lake, St. 3). On the basis of species/subspecies
identification by using RAPD analysis, we examined the species composition of the larvae and juveniles at these three sampling
sites. The number of specimens was 616, 68, and 117 at St. 1, St. 2, and St. 3, respectively. Based on morphological and genetic
identification, the specimens were found to include nine fish species/subspecies, namely, Carassius auratus grandoculis, Carassius cuvieri, Carassius auratus langsdorfii, Cyprinus carpio, Sarcocheilichthys sp., Silurus asotus, Oryzias latipes, Odontobutis obscura obscura, and Rhinogobius sp. The species composition at the three sites also differed. Among the Cyprininae fishes, C. auratus grandoculis, C. auratus langsdorfii, and Cyprinus carpio were found in abundance at St. 1; C. cuvieri was not collected from St. 1 but was found at the other two sites, particularly St. 3. Among the other fishes, Rhinogobius sp. was collected at St. 1 and St. 3, whereas the other four occurred only at St. 1. These results suggest that the selection
of spawning sites by C. cuvieri differs to a certain extent from that of the other Cyprininae fishes, and the irrigation ditch in the lake is an important
habitat for the larvae and juveniles of native fish species. 相似文献
18.
K. H. Rechinger 《Plant Systematics and Evolution》1980,134(3-4):287-292
Six new species are described:Teucrium chasmophyticum related toT. paederotoides from Northern Syria;Stachys subaphylla from North East Iran, the most xeromorphic representative of Sect.Ambleia; St. veroniciformis andSt. kermanshahensis, closely related to each other but rather isolated from the remainder of sect.Fragilicaulis; St. nephrophylla, still another member of the same section centred in West Iran, North Iraq and South East Turkey, related toSt. glechomifolia; andNepeta allotria from the Elburs mountains in North Iran, of isolated systematic position.
Florae Iranicae praecursores 10–15. 相似文献
19.
Utricularia sect. Foliosa Kamiénski comprises three recognized species, U. amethystina Salzm. ex A.St.-Hil. & Girard, U. tricolor A.St.-Hil., and U. tridentata Sylvén, delimited based mainly on shape and structure of the corolla. In comparison with the two latter members of the section, U. amethystina forms a complex of morphological variants, reflected taxonomically by the previous recognition of 31 synonyms. In his monograph of the genus, Taylor synonymized these taxa based primarily on his observation of continuous morphological variation of the flowers. In the same treatment he also suggested a future taxonomic re-evaluation could re-establish two, three or more taxa. Here we examine this question utilizing morphometric analyses of floral variation across most of the synonyms mentioned above, within populations from across their Neotropical distribution. Based on both morphological and geographic characters we identify strongly differentiated morphotypes. Our data provide support for both the maintenance of taxa previously recognised as synonyms under U. amethystina, and the resurrection of taxa to species status, namely U. bicolor, U. damazioi, U. lindmanii and U. hirtella, and four other putative new taxa. 相似文献
20.
采用顺序FISH-GISH技术,12个重复序列探针,包括9个三核苷酸简单重复序列、2个卫星DNA重复序列pSc119.2和pAs1以及5S rDNA,通过重复序列的物理定位对达乌里披碱草和垂穗披碱草基因组中部分重复序列的分布特征进行了比较分析,为进一步研究垂穗披碱草和达乌里披碱草的物种形成及演化提供新的分子细胞遗传学证据。结果表明:(1)所有的序列在这2个物种的染色体上都能产生可检测的杂交信号,且在2个物种中(AAC)_(10)、(ACT)_(10)、(CAT)_(10)都表现为共分布,(AAG)_(10)与(AGG)_(10)表现为近似共分布;2个物种的H基因组除5S rDNA序列外,其他序列都产生强烈且丰富的杂交位点,St与Y基因组不同重复序列探针的荧光位点数目有所差别,表现为5S rDNA、pSc119.2、(AAC)_(10)、(CAT)_(10)、(ACT)_(10)、(CAC)_(10)探针的信号位点较少或无信号,其余的探针信号位点稍多。(2)达乌里披碱草的第2对染色体上具有(AAC)_(10)、(CAT)_(10)、(ACT)_(10)的杂交位点、第6对染色体上具有(CAC)_(10)的杂交位点,而在垂穗披碱草的St基因组中未观察到上述序列杂交位点;达乌里披碱草St基因组仅有第4对染色体的端部具有pSc119.2杂交位点,而在垂穗披碱草St基因组中的pSc119.2杂交位点位于第5对染色体长臂的间隔区;相对于达乌里披碱草,垂穗披碱草St和Y基因组染色体含有更多的重复序列杂交位点。(3)达乌里披碱草的H/Y基因组间易位在不同材料间是稳定存在的,达乌里披碱草基因组相对稳定,不同材料间H基因组重复序列杂交信号多态性高于St和Y基因组;垂穗披碱草基因组的变异较大,不同材料间St和Y基因组重复序列杂交信号多态性高于H基因组。研究认为,垂穗披碱草和达乌里披碱草的H基因组均起源于布顿大麦,St基因组可能起源于不同的拟鹅观草属物种;与达乌里披碱草相比垂穗披碱草St与Y基因组可能具有更高的染色体结构变异性,而垂穗披碱草St与Y基因组变异较大的原因可能是与同区域分布的含StY基因组的物种发生了种间渗透杂交。 相似文献