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1.
通过对三明市的植物物种多样性调查结果表明:三明市有野生维管植物182科748属1652种(包括亚种、变种与变型)。区系分析表明三明市维管植物区系成分复杂,属的分布类型有14个,其中热带属463个,温带属285个,植物区系偏热带特性,具热带向温带过渡的特点。在此基础上,筛选出优良乡土园林植物资源449种,包括观赏蕨类43种、乔木类124种、灌木类96种、草本类130种、藤本类47种、竹子8种及棕榈科1种,分析了其园林应用潜力。 相似文献
2.
为弥补海南中部热带雨林区到滨海台地区的过渡地带丘陵区次生林群落物种多样性及区系研究的空缺,为海南中部丘陵地区次生林种子植物区系组成和恢复该地区物种多样性及保育提供理论依据,采用典型抽样法选取海南屯昌丘陵区不同类型次生林,对植物群落的物种多样性、区系地理成分进行调查研究。结果显示调查样地内共有维管植物87科201属267种,其中,蕨类植物3科3属4种,裸子植物2科2属2种,被子植物82科196属261种。群落的优势科为大戟科、茜草科、豆科、蔷薇科、梧桐科及樟科等。分析结果表明,该区种子植物区系起源古老,地理成分复杂,87个科中,世界分布、热带分布、温带分布的科分别有20、59和8个,显示明显的热带性质特征。200个属中,世界分布、热带分布、温带分布的属分别有1、169和30个,种类组成的科、属地理成分热带成分分别为67.81%和84.50%(不包括世界广布的科属),温带成分分别为9.10%和15.00%,表明以热带分布为主。群落垂直结构分为乔木层、灌木层和草本层,物种多样性指数显示,Margalef指数表现出灌木层最大,其次是乔木层、草本层;Shannon-Wiener指数表现为灌木层最大,其次是草本层和乔木层;Simpson指数是灌木层最大,其次是草本层、乔木层;Pielou指数则表现出草本层最大,灌木层其次,乔木层最小。 相似文献
3.
海南岛兰科植物区系的组成及其特征 总被引：7，自引：0，他引：7
海南岛是我国兰科植物分布最集中的地区之一,目前已发现有78属214种。其中,中国特有种31种(包括海南特有种14种),非中国特有种但在中国仅见于海南岛的有20种。种数在10种以上的属有羊耳蒜属(Liparis)、石斛属(Dendrobium)、毛兰属(Eria)、石豆兰属(Bulbophyllum)和兰属(Cymbidium)。海南岛兰科植物属的地理成分可划分为12个分布型和变型,其中热带亚洲成分占总属数的51.3%,热带分布属有71属,占绝对优势。海南岛兰科植物的生活型多样,附生兰有43属,地生兰有32属,腐生兰5属(其中羊耳蒜属和兰属中存在附生和地生2种生活型)。多个种在叶型和花色上变异较大,可作为优良育种材料。与邻近地区相比,海南岛兰科植物与西双版纳共有属最多(为56属),其次依序为台湾、广东、广西和福建。虽然海南岛与台湾和西双版纳同处热带北缘,受热带季风气候影响,但其兰科植物在属、物种和特有种的数量上比后两者要少。总的说来,海南岛的兰科植物区系较为多样,与亚洲热带兰科植物区系亲缘关系密切。 相似文献
4.
海南海岸禾草植物区系有野生植物140种(含变种、亚种)、82属。本区系热带性质明显,热带分布属占总属数(除去世界属和外来属)的94.6%,以泛热带分布、古热带分布、热带亚洲至热带非洲分布为主,分别占总属数的47.30%、16.22%、13.51%;热带分布种占总种数(除去广布种和外来种)的78.9%,又以热带亚洲分布、古热带分布、热带亚洲至热带大洋洲分布及泛热带分布为主,分别占总种数的35.16%、14.84%、12.50%、11.72%;该区系拥有较多的海岸植物群落优势种;探讨了本区系与周边地区、各大洲热带地区植物区系的联系;简要评价本区禾草植物资源。 相似文献
5.
本研究采取样线法和样方法调查相结合的技术路线,对连江5个无居民海岛的植物资源现状进行详细踏勘,根据所获得的实地调研数据以及对文献资料的查阅,运用植物区系地理学,对研究地的种子植物区系物种组成、科-属的分布区类型、分布生境类型等进行统计整理,与不同地区无居民海岛种子植物属的相似性系数和属的地理成分进行对比,并探讨5个无居民海岛之间维管束植物物种相似度以及与岛屿空间特征参数的关系。结果表明：（1）连江5个无居民海岛共有野生种子植物190种,隶属于64科165属;该种子植物区系的数量优势科为菊科、禾本科,大科、较大科、属种优势明显,寡种科、仅含1种的科数量多。生活型以草本（55.94%）和灌木（23.27%）居多,乔木和藤本数量不占优势,分别仅占13.86%和6.93%。（2）区系组成繁杂多样,在科、属水平上均以热带分布类型为首要,分别为90.24%、68.03%,其中泛热带分布分别占科、属的75.62%、36.05%,科级的温带类型只有9.76%,属级占31.97%,热带类型科-属与温带类型科-属的R/T值分别为9.25和2.13,表明连江5个无居民海岛种子植物区系主体为热带、亚热带成分,... 相似文献
6.
福建兰科植物地理成分与区系特点 总被引：2，自引：0，他引：2
福建兰科植物共有61属134种(包括中国特有种29种),其中地生兰37属79种,附生兰22属50种,腐生兰4属5种,兰属和羊耳蒜属存在有地生和附生2种生活型。区系地理分析表明,本区61属兰科植物可分为11个分布区型和4个变型,其中热带亚洲(印度-马来西亚)分布型及其变型属最多,共22属,占总属数的36.0%;本区134种兰科植物则可分为11个分布区型和3个变型,其中热带亚洲(印度-马来西亚)分布型最多,共有30种,占总种数的22.4%;其次为中国特有分布型,共有27种,占总种数的20.1%。虽然属、种的区系地理成分复杂多样,但区系整体与热带亚洲区系关系密切,热带成分占绝对优势,并受到北温带植物区系影响,而与温带亚洲、地中海、西亚和中亚植物区系几乎没有联系;区系发生年代较为年轻,区系过渡带特征明显;区域分布不均,单种属、寡种属占优势,种内变异大。 相似文献
7.
青云山省级自然保护区位于韶关翁源县的东南部,本研究在查阅文献、历史标本的基础上,对本区进行全面踏查、标本采集并鉴定,从而进行植物物种多样性编目和区系分析。结果表明：青云山自然保护区有维管束植物1336种（含种下分类单位）,其中石松类和蕨类植物132种,隶属于62属24科,裸子植物6种,隶属于4属4科,被子植物1198种,隶属于588属148科;本区的表征科主要以樟科（Lauraceae）、壳斗科（Fagaceae）、冬青科（Aquifoliaceae）等为主。植物区系地理组成复杂,主要以热带、亚热带为主,且热带、亚热带的过渡性质明显。从中国特有种的分布情况来看,该地区与湖南南部、广西东北部、江西西南部联系较为紧密,体现了南岭山脉植物区系的一致性与整体性;珍稀濒危植物共计48种;植被具有中亚热带向南亚热带过渡的特征。青云山自然保护区植物物种丰富度高、植被类型多样,建议将园洞、青山口等珍稀濒危植物分布较集中的地区列为优先保护区域。 相似文献
8.
对福建省野生豆科植物资源调查表明,福建省野生豆科植物有233种80属(包括变种、亚种),其中单种属、2～4种属居多并占绝对优势,分别占总属数的47.50%和30.50%。对福建省野生豆科植物资源生态地理区系分析表明,植物区系成分在属、种的水平上有13个类型,4个亚型,植物区系特征在属的水平上以热带成分为主,其中热带分布属有53属,占总属数的68.83%,可见本区系属的热带成分占明显优势,具有明显的热带性质。在种的水平上以泛热带分布类型占较大比例,其他多种分布类型并存,表现为丰富的物种多样性特征。 相似文献
9.
对海南北部8处火山村建筑墙体植物进行了调查研究,以便了解其物种多样性和生态价值。研究结果表明:上述火山村共记录有88种墙体植物,隶属于43科77属。其中,蕨类植物6科8属8种,占总物种数的9.09%;被子植物37科69属80种,占90.91%。88种墙体植物中本地种68种,占77.27%;栽培种5种,归化种1种,逸生种4种,外来入侵种10种,分别占总物种数的5.68%、1.14%、4.55%和11.36%。就生态型而言,木本植物和草本植物的比例分别为43.18%和56.82%。88种墙体植物中共计有79种为热带分布型,占总物种数的89.77%。研究发现,火山石建筑墙体能很好的保存本地物种,避免其因农业生产活动而损失殆尽。因而在开展古村落保护和乡村旅游时,应科学合理地保护和利用这些墙体植物,实现生物多样性保护和古建筑保护的兼顾。 相似文献
10.
[目的]研究海南七仙岭裂苞省藤群落的物种组成以及群落特征。[方法]采用样方调查法,统计样方内乔木(胸径大于2 cm)的胸径、树高、种名,同时记录裂苞省藤的萌蘖数和长度;记录灌木(胸径小于2 cm且株高大于50 cm)的种名、株高和株数,以及草本植物(株高低于50 cm)的种名、盖度。[结果](1)在1 200 m2样方中,裂苞省藤密度为24.11%;共记录维管植物129种,隶属51科97属。(2)群落植物科以泛热带分布类型最为丰富,植物属以热带亚洲分布类型最为丰富;以大戟科、梧桐科、番荔枝科和樟科为优势科,野桐属、柿属和山矾属为优势属。(3)乔木层物种丰富度最大,多样性指数变化趋势为乔木层>草本层>灌木层,均匀性指数的变化趋势均表现为草本层>灌木层>乔木层。(4)裂苞省藤幼苗在该群落占较高的优势,具有较高的重要值,反映该藤种在群落处于发育的初级阶段。[结论]不仅为生物多样性研究提供物质基础,还为裂苞省藤资源保存提供针对不同种类和生长阶段的种源知识贮备,对天然藤林可持续经营具有重要意义。 相似文献
11.
12.
《Journal of Crop Improvement》2013,27(2):81-114
Summary The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices. 相似文献
13.
Lakshman Lal 《Potato Research》1987,30(2):329-334
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong
(1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage,
sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over
45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield
of a subsequent crop. 相似文献
14.
15.
Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献
16.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results
for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin
presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear
relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins
and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds. 相似文献
17.
Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity. 相似文献
18.
Alejandro Carlos Tozzini María Fernanda Ceriani María Verónica Saladrigas H. Esteban Hopp 《Potato Research》1991,34(3):317-324
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets
that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and
slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging
toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta.
Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact). 相似文献
19.
Rita Favas Janaína Morone Rosrio Martins Vitor Vasconcelos Graciliana Lopes 《Marine drugs》2022,20(3)
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms. 相似文献
20.
Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories. 相似文献