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1.
Longidorus fagi n. sp. is described from Vitosha Mountain, Bulgaria, where it was found in soil around roots of Fagus sylvatica L. The new species is characterised by its medium size, narrow anteriorly rounded lip region which is offset from the body by a very slight depression, large amphidial pouches which are distinctly bilobed at the base, and a conoid-elongate tail which is ventrally curved with a narrow, rounded terminus. L. fagi resembles L. nirulai, L. distinctus, L. curvatus and L. fragilis, An identification key for species of the genus Longidorus present in Bulgaria is provided. 相似文献
2.
MAUREEN DOCHERTY FRANCES WADE DEBRA HURST JOHN WHITTAKER & PETER LEA 《Global Change Biology》1997,3(1):51-59
Five species of sap-feeding homoptera were studied on Fagus sylvatica and Acer pseudoplatanus and exposed to elevated concentrations of carbon dioxide (600 μL L–1 ). The concentration of total soluble amino acids in foliage of F. sylvatica was unaffected by growing saplings in elevated atmospheric CO2 concentrations. Although experiments on individual aphids indicated poorer performance of Phyllaphis fagi (fewer, smaller nymphs produced), resultant populations did not differ from those in ambient (350 μL L–1 ) conditions. The area of beech foliage stippled by the leafhopper Fagocyba cruenta was similar at ambient and elevated CO2 concentrations. The concentration of total amino acids and that of serine of A. pseudoplatanus foliage were significantly lower at elevated CO2 concentrations. However, the relative growth rates of two aphid species Drepanosiphum platanoidis and Periphyllus testudinaceus and one leafhopper Ossiannilssonola callosa were not significantly different in elevated CO2 . No evidence was found that, under the conditions of these experiments, populations of aphids and leafhoppers will change as concentrations of CO2 increase. 相似文献
3.
Carbon dioxide-induced changes in beech foliage cause female beech weevil larvae to feed in a compensatory manner 总被引:1,自引:0,他引:1
MAUREEN DOCHERTY DEBRA K. HURST JARMO K. HOLOPAINEN† JOHN B. WHITTAKER PETER J. LEA ALLAN D. WATT‡ 《Global Change Biology》1996,2(4):335-341
The phenology of Fagus sylvatica was unaffected by exposure to an atmosphere of elevated CO2 (600 μL L-1 ) after two years of fumigation. Non-significant changes in nitrogen and phenolic content of the leaves decreased the nutritional status of beech for female larvae in elevated CO2 such that they responded by eating in a compensatory manner; males were unaffected. Rates of development, mortality and adult biomass of Rhynchaenus fagi were no different from those in ambient CO2 concentrations (355 μL L -1 ). It is possible that, with the changes in leaf chemistry affecting the females, fecundity will be altered, with important consequences for populations of beech weevil. 相似文献
4.
The identification of Scolytus fagi Walsh has been difficult because of the lack of diagnostic literature, the occurrence of several morphologically similar sympatric Scolytus species and the loss of the syntypes. In an effort to reduce taxonomic confusion, we designate a neotype for Scolytus fagi, redescribe the male and female, add new distributional records and create a key for the identification of eastern Scolytus species. 相似文献
5.
Abstract. (1) The spatial distribution pattern of herbivory by phyllophagous canopy arthropods in a 90-year-old beech stand was analysed.
(2) Two main patterns of spatial distribution were recorded. The leaf mining moths Phyllonorycter maestingella and Stigmella hemargyrella and the adult weevils Rhynchaenus fagi and Phyllobius argentatus mainly attacked the under-story and the latter species especially the low canopy in the central part of the stand. Mines of R. fagi chiefly occurred in the top of the overstory canopy or at the fringe of the stand. However, comparable distribution patterns are only expected in mature beech stands composed of distinct overstory and understory layers.
(3) The effect of the actual spatial distribution pattern of herbivory on photosynthesis, productivity, and transpiration of beech in the research stand is discussed. It is suggested that in some cases the shade leaves of the understory canopy may cushion the effect of herbivory in the beech stand. 相似文献
(2) Two main patterns of spatial distribution were recorded. The leaf mining moths Phyllonorycter maestingella and Stigmella hemargyrella and the adult weevils Rhynchaenus fagi and Phyllobius argentatus mainly attacked the under-story and the latter species especially the low canopy in the central part of the stand. Mines of R. fagi chiefly occurred in the top of the overstory canopy or at the fringe of the stand. However, comparable distribution patterns are only expected in mature beech stands composed of distinct overstory and understory layers.
(3) The effect of the actual spatial distribution pattern of herbivory on photosynthesis, productivity, and transpiration of beech in the research stand is discussed. It is suggested that in some cases the shade leaves of the understory canopy may cushion the effect of herbivory in the beech stand. 相似文献
6.
中国叶蚜亚科分类学研究(同翅目,蚜科) 总被引:3,自引:3,他引:0
中国叶蚜亚科Phyllaphidinae已知4属,迪叶蚜属Diphyllaphis Takahashi,1960,楠叶蚜属Machilaphis Takahashi,1960,叶蚜属Phyllaphis Koch,1856和群斑蚜属Thelazacallis Zhang,2000;4个种,栎迪叶蚜Diphyllaphis quercus (Takahashi,1960),楠叶蚜Machilaphis machili(Takahashi,1928),山毛榉叶蚜Phyllaphis fagi(Linnacus,1767)和毛茛群斑蚜Thelazacallis ranunculicola Qiao et Zhang,2000.其中叶蚜属和山毛榉叶蚜为中国新纪录.文中提供了分属检索表,各属提供了鉴别特征,所有分类单元提供了文献引证、寄主植物、地理分布和检视标本的记录.新纪录种有详细的形态记述和特征图.研究标本保存在中国科学院动物研究所动物标本馆. 相似文献
7.
Ternstroemia sylvatica is a plant reputed popularly to possess a anxiolytic properties but has not yet been systematically tested for such activity. The behavioral actions of T. sylvatica were examined using the open field test, the elevated plus-maze test, and the forced swim test in male rats. T. sylvatica (7.1 mg/kg and 14.2 mg/kg, i.p.) reduced ambulatory behavior in the open field test and cancelled the anti-immobility actions produced by desipramine (32 mg/kg, i.p.) in the forced swim test, as did diazepam. In the elevated plus-maze test, T. sylvatica (7.1 mg/kg, i.p.) failed to show anxiolytic actions. It is concluded that Ternstroemia sylvatica produces sedative effects rather than the attributed anxiolytic actions. 相似文献
8.
欧洲水青冈(Fagus sylvatical L.)构筑型与形态多样性研究 总被引:14,自引:0,他引:14
通过对植物构件和构筑型的分析,可以了解植物的整体结构与系统演化关系。高等植物构筑型的研究以树木最为深入,植物学家对全球的树木进行了构筑模式的分类,并确定了23个基本的构筑类型。植物的构筑型和其形态的多样性是密不可分的。构筑奕型确定了植物所属的整体形态类型,而对每种植物具体的形态多样性分析可以深入了解每种构筑型的数量特征及其形成过程。在概述了树木树筑型研究的基础上,系统说明了欧洲水青冈构筑才形态多样性分析的步骤和步骤和分析的意义。水青冈属(Fagus)为Troll型构筑模式,处于不同生态条件下的同一种的不同种群之间,在形态、解剖、生理和遗传多样性方面都存在着差异。树木的形态多样性虽然主要受遗传因素的控制,但生态条件对其形态和遗传多样性也有非常显著的影响。在对树木进行构筑型分析时,道德要根据构筑要素(主要是形态与生长特性)确定它所属的构筑类型,其次是分析它的形态特征与环境条件的关系,进行进一步分析其遗传多样性。 相似文献
9.
We have compared the primary sequence and enzymatic properties of the sarcoplasmic reticulum Ca(2+)-ATPases from a cold-tolerant frog Rana sylvatica with those of a closely related cold-intolerant frog, Rana clamitans. Sarcoplasmic reticulum isolated from leg muscles of both species contains a major protein ( approximately 100 kDa) that reacts with a monoclonal antibody against sarco(endo)plasmic reticulum Ca(2+)-ATPase type 1 (SERCA1). The apparent molecular mass of R. sylvatica SERCA1 is 115 kDa, whereas that of R. clamitans is 105 kDa. However, the deduced amino acid sequences obtained from cDNAs do not indicate a difference in molecular weight, thus suggesting post-translational protein modification of R. sylvatica SERCA1. Comparison of the temperature dependence of both ATP hydrolysis and Ca(2+) transport indicates that R. sylvatica SERCA1 exhibits significantly lower activation energy below 20 degrees C and an approximately 2-fold greater Ca(2+)-ATPase activity near 0 degrees C. Furthermore, R. sylvatica SERCA1 exhibits simple Michaelis-Menten kinetics with ATP and Ca(2+) as opposed to the two-site ATP kinetics and positive cooperativity with Ca(2+) observed for R. clamitans and mammalian SERCA1s. Cooperativity has been linked to protein-protein interaction in SERCA1, and this property may be altered in R. sylvatica SERCA1. Primary sequence comparison shows that R. sylvatica SERCA1 exhibits seven unique amino acid substitutions, three of which are in the ATP binding domain. We also report for the first time the presence of alternative splicing in the frog, resulting in isoforms SERCA1a and SERCA1b. Thus, it appears that the low temperature muscle contractility of R. sylvatica can be explained partially by significant functional and structural differences in SERCA1. 相似文献
10.
A cDNA clone was selected from a cDNA library constructed using mRNA from ABA-treated Fagus sylvatica L. dormant seeds as a template. The clone is highly expressed in the presence of ABA and tends to disappear in stratified seeds. A search of sequence databases showed that the clone encodes a small GTP-binding protein. By means of in situ hybridization, the mRNA has been located in the apical meristem of the embryonic axis and in the central vascular cylinder. Its possible involvement in growth regulation in the embryonic axis of F. sylvatica is discussed. 相似文献
11.
Abstract. 1. In laboratory experiments, R.fagi made feeding holes in eighteen tree and shrub species, including beech, from seven plant families but few plants other than beech were eaten to any extent.
2. Overwintered adult weevils preferred beech to all these eighteen plants in spring.
3. Hawthorn and raspberry were the most acceptable plants if beech was not available at this time.
4. Field collected weevils from hawthorn had partly developed oocytes in early April, prior to beech bud burst.
5. New generation weevils sought alternative food sources in late June and July; raspberry was preferred to the youngest available beech leaves at this time. 相似文献
2. Overwintered adult weevils preferred beech to all these eighteen plants in spring.
3. Hawthorn and raspberry were the most acceptable plants if beech was not available at this time.
4. Field collected weevils from hawthorn had partly developed oocytes in early April, prior to beech bud burst.
5. New generation weevils sought alternative food sources in late June and July; raspberry was preferred to the youngest available beech leaves at this time. 相似文献
12.
G. BLUNDEN R. HARDMAN F. J. HIND 《Botanical journal of the Linnean Society. Linnean Society of London》1971,64(4):431-446
The morphology of Dioscorea sylvatica from Natal and the hills in the Lydenburg district of the Transvaal is described, as well as the anatomy of the leaf and stem. Differences were noticed between the Natal and Lydenberg types which are inconsistent with Burkill's classification of the species. From the differences it is suggested that the Lydenberg type be designated as D. sylvatica subspecies lydenbergensis subsp. nov. 相似文献
13.
J. J. B. Gill A. J. Cain 《Biological journal of the Linnean Society. Linnean Society of London》1986,28(3):315-320
The karyotype of Cepaea vindobonensis (Pfeiffer) (2 n = 50) is defined and compared with those of C. sylvatica (Draparnaud), C. nemoralis (L.) and C. hortensis (Müller). Cepaea vindobonesis shares its chromosome number with C. sylvatica. The genus Cepaea thus consists of two pairs of species, one with 2 n = 50 the other with 2 n = 44. The karyotype of C. vindobonensis is distinct from that of C. sylvatica as it lacks any discontinuity in its range of chromosome length and has all three of its longest chromosome pairs nearly identical. The two 2 n = 50 species both have an unusual meiotic bivalent showing a 'satellite-type' structure. It is apparent that the 2 n = 50 species are more closely related to each other than to the 2 n = 44 species. No precise definition of the evolutionary history can be given but a working hypothesis is suggested. 相似文献
14.
In this study, two methods are used to assess the equilibrium and dynamic cell volumes in Rana sylvatica liver tissue during freezing in the presence and absence of a cryoprotectant (glucose). The first is a "two-step" low-temperature microscopy (equilibrium and dynamic) freezing method and the second is a differential scanning calorimeter (DSC) technique. These two techniques were used to study (i) the in vitro architecture of R. sylvatica frog liver tissue and to measure its characteristic Krogh cylinder dimensions; (ii) the "equilibrium" (infinitely slow) cooling behavior and the osmotically inactive cell volume (V(b)) of R. sylvatica liver cells; and (iii) the dynamic water transport response of R. sylvatica liver cells in the presence and absence of the CPA (glucose) at a cooling rate of 5 degrees C/min. Stereological analysis of the slam frozen (>1000 degrees C/min) micrographs led to the determination that 74% of the liver tissue in control frogs was cellular versus 26% that was extracellular (vascular or interstitial). Mapping the stereological measurements onto a standard Krogh cylinder geometry (Model 1) yielded distance between adjacent sinusoid centers, DeltaX = 64 microm; original sinusoid (vascular) radius, r(vo) = 18.4 microm; and length of the Krogh cylinder, L = 0.71 microm (based on an isolated frog hepatocyte cell diameter of 16 microm). A significant observation was that approximately 24% of the frog hepatocyte cells are not in direct contact with the vasculature. To account for the cell-cell contact in the frog liver architecture a modified Krogh cylinder geometry (Model 2) was constructed. In this model (Model 2) a second radius, r(2) = 28.7 microm, was defined (in addition to the original sinusoid radius, r(vo) = 18.4 microm, defined above) as the radius of the membrane between the adjacent cells (directly adjacent to vascular spaces) and embedded cells (removed from vascular spaces). By plotting the two-step equilibrium cooling results on a Boyle-van't Hoff plot, the osmotically inactive cell volume, V(b) was obtained as 0.4. V(o) (where V(o) is the isotonic cell volume). The two-step dynamic micrographs and the heat release measurements from the DSC were used to obtain water transport data during freezing. The DSC technique confirmed that R. sylvatica cells in control liver tissue do not dehydrate completely when cooled at 5 degrees C/min but do so when cooled at 2 degrees C/min. 相似文献
15.
Georges Kunstler Wilfried Thuiller Thomas Curt Monique Bouchaud René Jouvie Florian Deruette Jacques Lepart 《Diversity & distributions》2007,13(6):799-807
Native tree populations have been fragmented by anthropogenic disturbance worldwide, leaving them at risk from extinction. The possibility of sizable recovery of fragmented populations is a function of their dispersal, the abiotic conditions, and the biotic interactions. The relative importance of these three drivers for the recruitment rate of a fragmented population of the late-successional Fagus sylvatica L. was analysed at the landscape scale in Causse du Larzac, southern margins of the Massif Central, in the South of France. We used regression models on observational data to analyse the response of Fagus recruitment rate to the distance to the nearest mature population, to climatic and geological variables, and to variables describing biotic interactions (pine vs. grassland, light, shrub cover). Distance to the nearest F. sylvatica adult population was the most important explanatory variable. Recruitment rate was also influenced by facilitative biotic interactions with shrubs, and by the climatic conditions of the plot. Recruitment occurred at a greater distance from the nearest mature population of Fagus in pine forests than in grassland. Dispersal was the major limitation to recruitment of F. sylvatica in this landscape. The recruitment rate was then modulated by the climate and positive biotic interactions. The activity of the European jay could be of great importance for such fragmented populations, because it can lead to long-distance dispersal events and may result in a preferential dispersal towards pine forests. 相似文献
16.
The Holocene history of low altitude Mediterranean Fagus sylvatica forests in southern France
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Julien Azuara Vincent Lebreton Odile Peyron Florence Mazier Nathalie Combourieu‐Nebout 《植被学杂志》2018,29(3):438-449
Questions
As the dominant tree in many European forests, Fagus sylvatica functions as an ecosystem engineer, yet its istory remains little understood. Here we ask: (a) are there indications for its presence in southeast France during the last Glacial period; (b) what was the timing of the expansion and decline of F. sylvatica dominated forests; (c) which factors influenced their dynamics and in particular to what extent did past precipitation changes impact upon them; and (d) at which altitudes did these beech forests occur within the region?Location
Languedoc, the French Mediterranean area.Method
This article presents a well dated and high‐resolution pollen sequence covering the last 7,800 years from the Palavas Lagoon in the Languedoc together with a review of Fagus charcoal occurrences in the Languedoc and the lower Rhône Valley, and a review of pollen data from a compilation of 69 sites in southeast France.Results
The Palavas pollen sequence provides a regional summary of F. sylvatica abundance changes near the Mediterranean coast. Around 6,000 years cal BP , an abrupt transition from small beech populations to well‐developed forests is recorded. The maximum development of beech forests occurred between 4,000 and 3,000 years cal BP , while F. sylvatica started to regress after 3,000 years cal BP .Conclusion
Scattered F. sylvatica populations probably survived throughout southern France during the last Glacial period. F. sylvatica started to spread around 8,000 years cal BP while beech forests never expanded before 6,000 years cal BP . The complex patterns of F. sylvatica expansion in southern France after 6,000 years cal BP suggests that a combination of global (climate change) and local (human impact) factors were responsible for this major change. Recurrent abrupt climate changes, the aridity trend and human deforestation caused beech forests to decline after 3,000 years cal BP .17.
In freeze tolerant wood frog Rana sylvatica, the freeze-induced liberation of glucose plays a critical role in survival in response to sub-zero temperature exposure. We have shown that the glycaemic response is linked to selective changes in the expression of hepatic adrenergic receptors through which catecholamines act to produce their hepatic glycogenolytic effects. The purpose of the present study was to determine if skeletal muscle, another catecholamine-sensitive tissue with glycogenolytic potential, displayed similar or different changes. In order to achieve these objectives, skeletal muscle derived from Rana sylvatica was studied in control, frozen and thawed states. In isolated sarcolemmal fractions, freezing effected an 88% decrease in beta(2)-adrenergic receptor expression but was without effect on the calcium pump; while thawing resulted in a recovery of the beta(2)-adrenergic receptor to 60% of control levels and a 2.4-fold increase in calcium transport. In isolated sarcoplasmic reticular fractions, freezing effected a 52% decrease in calcium binding and a 92% decrease in oxalate-stimulated calcium uptake; while thawing elicited partial normalization to control levels to 70% with respect to calcium binding and to 47% with respect to calcium uptake. Freezing and thawing were associated with increases and decreases, receptively, in blood glucose levels but were without effect on skeletal muscle glycogen content. Thus these muscle changes in Rana sylvatica in freezing and thawing are not linked to glycogen breakdown, are different from those previously seen in liver, and may provide a role in recovery of muscle function during thawing by protecting glycogen stores for contraction and maximizing extracellular calcium for excitation-contraction coupling in the frozen state. The involvement of thyroid hormone in triggering these muscle changes is discussed. 相似文献
18.
7-Caffeoylsedoheptulose has been isolated from the wood of Nyssa sylvatica, along with two ellagic acid derivatives and scopoletin. Its structure was established by chemical and spectral evidence. 相似文献
19.
20.
Reyes D Rodríguez D Lorenzo O Nicolás G Cañas R Cantón FR Canovas FM Nicolás C 《Journal of experimental botany》2006,57(4):923-929
An enzymatically active recombinant protein kinase, previously isolated and characterized in Fagus sylvatica L. dormant seeds (FsPK1), was used to obtain a specific polyclonal antibody against this protein. Immunoblotting and immunohistochemical analysis of FsPK1 protein in beech seeds showed a strong immunostaining in the nucleus of the cells located in the vascular tissue of the embryonic axis corresponding to the future apical meristem of the root. This protein kinase was found to accumulate in the seeds only when embryo growth was arrested by application of ABA, while the protein amount decreased during stratification, previously proved to alleviate dormancy, and no protein was detected at all when seed germination was induced by addition of GA(3). These results indicate that FsPK1 may be involved in the control of the embryo growth mediated by ABA and GAs during the transition from dormancy to germination in Fagus sylvatica seeds. 相似文献