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Spruce Seedlings (spruce + seedling)

Distribution by Scientific Domains

Life Sciences	55%
Earth and Environmental Science	33%

Kinds of Spruce Seedlings

norway spruce seedling

Selected Abstracts

Ants accelerate succession from mountain grassland towards spruce forest

JOURNAL OF VEGETATION SCIENCE, Issue 4 2009
Blanka Vlasáková
Abstract Question: What is the role of mound-building ants (Lasius flavus) in successional changes of a grassland ecosystem towards a spruce forest? Location: Slovenské Rudohorie Mountains, Slovakia; ca. 950 m a.s.l. near the Obrubovanec point (1020 m a.s.l.; 48°41,N, 19°39,E). Methods: Both chronosequence data along a successional gradient and temporal data from long-term permanent plots were collected on ants, spruce establishment, and vegetation structure, together with additional data on spruce growth. Results: There are more spruce seedlings on ant mounds (4.72 m,2) than in the surrounding vegetation (0.81 m,2). Spruce seedlings grow faster on these mounds compared to surrounding areas. The first colonization wave of seedlings was rapid and probably occurred when grazing prevailed over mowing. Ant colony presence, mound volume, and plant species composition change along the successional gradient. Mounds become bigger when partly shaded but shrink in closed forest, when ant colonies disappear. Shade-tolerant acidophylic species replace grassland plants both on the mounds and in surrounding areas. Conclusions: The massive occurrence of Lasius flavus anthills contributes to a runaway feedback process that accelerates succession towards forest. The effect of ants as ecosystem engineers is scale-dependent: although they stabilize the system at the scale of an individual mound, they may destabilize the whole grassland system over a longer time scale if combined with changes in mowing regime. [source]

Rhizomorph production and stump colonization by co-occurring Armillaria cepistipes and Armillaria ostoyae: an experimental study

FOREST PATHOLOGY, Issue 1 2006
S. Prospero
Summary In managed spruce forests, Armillaria cepistipes and A. ostoyae are efficient stump colonizers and may compete for these resources when they co-occur at the same site. The aim of this experiment was to quantify the mutual competitive ability of the two Armillaria species in producing rhizomorphs and in colonizing Norway spruce (Picea abies) stumps. Five isolates of A. cepistipes and two isolates of A. ostoyae were simultaneously inoculated pair-wise into pots containing a 4-year-old spruce seedling. For comparison, each isolate was also inoculated alone. One year after inoculation, stumps were created by cutting down the seedlings. Six months after creation of the stumps, rhizomorph production and stump colonization were assessed. Armillaria spp. were identified from 347 rhizomorphs and 48 colonized stumps. Armillaria cepistipes dominated both as rhizomorphs in the soil and on the stumps. Nevertheless, A. ostoyae was relatively more frequent on the stumps than in the soil and A. cepistipes was relatively more frequent in the soil than on the stumps. In both species, the ability to colonize the stumps in simultaneous inoculations was significantly reduced compared with single inoculations. In respect to rhizomorph production, simultaneous co-inoculations had a slightly stimulatory effect on A. cepistipes and no significant effect on A. ostoyae. Our study suggests a rather neutralistic co-existence of A. cepistipes and A. ostoyae as rhizomorphs in the soil. Concerning the ability to colonize stumps, the two species experience a mutual negative effect from the interaction, probably because of interspecific competition. Résumé Dans les forêts gérées d'épicéas, Armillaria cepistipes et Armillaria ostoyae sont de bons colonisateurs de souches et sont en compétition pour cette ressource quand ils sont présents ensemble dans le même site. L'objectif de l'expérimentation était de quantifier l'aptitude compétitive mutuelle des deux espèces d'Armillaria pour la production de rhizomorphes et la colonisation de souches d'épicéa commun (Picea abies). Cinq isolats de A. cepistipes et deux isolats de A. ostoyae ont été inoculés simultanément par paires dans des pots contenant chacun un semis d'épicéa de 4 ans. Chaque isolat a également été inoculé seul, à titre de comparaison. Un an après inoculation, les semis ont été coupés pour créer des souches. Six mois après la coupe, la production de rhizomorphes et la coloniasation des souches ont été estimées. Armillaria spp. a été identifiéà partir de 347 rhizomorphes et 48 souches colonisées. A. cepistipes domine à la fois sous forme de rhizomorphes dans le sol et dans les souches. Toutefois, A. ostoyae est relativement plus fréquent sur souches que dans le sol alors que l'inverse est observé pour A. cepistipes. Pour les deux espèces, l'aptitude à coloniser les souches a significativement été réduite dans le cas des inoculations simultanées par rapport aux inoculations simples. En ce qui concerne la production de rhizomorphes, les inoculations simultanées ont eu un léger effet stimulant sur A. cepistipes et pas d'effet significatif sur A. ostoyae. Nos résultats suggèrent une co-existence relativement neutre entre A. cepistipes et A. ostoyaeà l'état de rhizomorphes dans le sol. Concernant l,aptitude à coloniser les souches, les deux espèces subissent un effet négatif mutuel de l'interaction, provenant probablement de la compétition interspécifique. Zusammenfassung In bewirtschafteten Fichtenwäldern sind Armillaria cepistipes und Armillaria ostoyae effiziente Besiedler von Baumstümpfen und sie können um diese Ressource miteinander konkurrieren, da sie häufig gemeinsam vorkommen. Es wurde ein Experiment durchgeführt mit dem Ziel, die wechselseitige Konkurrenzfähigkeit dieser beiden Armillariaarten bezüglich ihrer Rhizomorphenproduktion und ihrer Fähigkeit zur Besiedlung von Fichtenstümpfen (Picea abies) zu quantifizieren. Fünf Isolate von A. cepistipes und zwei Isolate von A. ostoyae wurden gleichzeitig paarweise in Töpfe mit einem vierjährigen Fichtensämling inokuliert. Zum Vergleich wurde jedes Isolat auch alleine inokuliert. Ein Jahr nach der Inokulation wurden durch Abschneiden der Pflanzen Stümpfe erzeugt. Sechs Monate nach dem Schnitt wurde die Rhizomorphenproduktion und die Besiedelung der Stümpfe erfasst. Die beiden Arten wurden aus 347 Rhizomorphen und 48 besiedelten Stümpfen reisoliert. Armillaria cepistipes dominierte sowohl in Form von Rhizomorphen im Boden als auch in den Stümpfen. Armillaria ostoyae kam häufiger in den Stümpfen vor als im Boden und A. cepistipes wurde häufiger im Boden gefunden als in den Stümpfen. Bei beiden Arten war die Fähigkeit zur Stumpfbesiedelung bei gleichzeitiger Inokulation im Vergleich zur Einzelinokulation signifikant reduziert. Die gleichzeitige Inokulation mit beiden Arten stimulierte die Rhizomorphenproduktion bei A. cepistipes leicht, hatte aber keinen signifikanten Einfluss auf A. ostoyae. Diese Befunde deuten auf eine weitgehend neutrale Koexistenz der Rhizomorphen von A. cepistipes und A. ostoyae im Boden hin, bezüglich ihrer Fähigkeit zur Stumpfbesiedelung hemmen sich beide Arten aber gegenseitig. Dieser Effekt ist wahrscheinlich durch interspezifische Konkurrenz zu erklären. [source]

Soil exploration, nutrient partitioning, and nutrient efficiency of beech and spruce seedlings in a rhizotrone experiment

JOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 3 2003
Zhenyu Wang
[source]

Ants accelerate succession from mountain grassland towards spruce forest

Cytological and enzymatic responses to aluminium stress in root tips of Norway spruce seedlings

NEW PHYTOLOGIST, Issue 3 2004
Nina Elisabeth Nagy
Summary ,,Aluminium (Al) stress reduces plant growth. However, some species such as Norway spruce (Picea abies) seem to tolerate high Al concentrations. The aim of this study was to investigate characteristics possibly involved in Al tolerance in Norway spruce seedlings. ,,Seedlings (10-d-old) were exposed to Al3+ concentrations of 0.5 and 5 mm for up to 168 h. The effect of Al stress on root growth, cell morphology and Al distribution, callose production, and peroxidase and chitinase activity was analysed. ,,Root growth decreased after 1 d and 2 d with 5 and 0.5 mm Al, respectively. Callose concentration increased strongly after 6 h treatment with 5 mm Al. The activity of many peroxidase and chitinase isoforms decreased after 1,24 h exposure of both treatments. Several isoforms increased after 48,168 h exposure to 5 mm Al. ,,We postulate that, with external Al concentrations 0.5 mm or lower, an increased production above constitutive levels of peroxidase or chitinase is not required for Al tolerance in young Norway spruce seedlings. High constitutive levels of peroxidase and chitinase in this species may be part of this Al tolerance. [source]

Isolation of high-quality RNA from white spruce tissue using a three-stage purification method and subsequent cloning of a transcript from the PR-10 gene family

PHYTOCHEMICAL ANALYSIS, Issue 4 2003
Nathalie Mattheus
Abstract Isolation of PinmIII cDNA homologues from white spruce tissues required a rigorous RNA extraction protocol developed following assessment of three previously reported conifer RNA extraction protocols. Total RNA was extracted via several purification steps designed to minimize binding of phenolics to nucleic acids and was then subjected to caesium chloride ultra-centrifugation. This procedure produced consistently high-quality, intact RNA from both needles and roots with spectrophotometric ratios of approximately 2.0 for both 260/280,nm and 260/230,nm. Total RNA was obtained from the roots of cold-hardened white spruce seedlings for cDNA library construction. More than 2 million recombinant phage particles were generated from 5,µg of a poly(A)+RNA fraction, and ca. 1.3 million cDNA particles were amplified for storage. Approximately 500,000 primary recombinant clones were screened with an heterologous PinmIII cDNA sequence yielding a unique clone, picg1, that was very similar to members of the PR10 gene family. Copyright © 2003 John Wiley & Sons, Ltd. [source]

Effects of red, far-red and blue light in maintaining growth in latitudinal populations of Norway spruce (Picea abies)

PLANT CELL & ENVIRONMENT, Issue 2 2006
JØRGEN ALEXANDER MØLMANN
ABSTRACT Seedlings of trees with a free growth pattern cease growth when night-lengths become shorter than a critical value, and this critical night-length (CNL) decreases with increasing latitude of origin. In northern populations, the light quality also appears to play an important role and a clinal variation in requirement for far-red (FR) light has been documented. In this study we dissected the light quality requirements for maintaining growth in different latitudinal populations of Norway spruce (Picea abies (L.) H. Karst.) using light emitting diodes for red (R), FR and blue (B) light, as 12 h day extension to provide 24 h photoperiod. At equal spectral photon flux, FR light was more effective than R light in maintaining growth, and the requirement of both R and FR increased with northern latitude of origin. One-to-one mixtures of R and FR light were more effective in maintaining growth than either FR or R light alone, indicating a possible interaction between R and FR light maintaining growth. Using the blue light as day extension could not prevent growth cessation in any of the populations, but delayed the bud set slightly in all populations. Our results suggest that phytochrome(s) are the primary photoreceptors in high irradiance responses maintaining growth in Norway spruce seedlings. [source]

Extracellular complexation of Cd in the Hartig net and cytosolic Zn sequestration in the fungal mantle of Picea abies , Hebeloma crustuliniforme ectomycorrhizas

PLANT CELL & ENVIRONMENT, Issue 11 2000
B. Frey
ABSTRACT Compartmentation of heavy metals on or within mycorrhizal fungi may serve as a protective function for the roots of forest trees growing in soils containing elevated concentrations of metals such as Cd and Zn. In this paper we present the first quantitative measurements by X-ray microanalysis of heavy metals in high-pressure frozen and cryosectioned ectomycorrhizal fungal hyphae. We used this technique to analyse the main sites of Cd and Zn in fungal cells of mantle and Hartig net hyphae and in cortical root cells of symbiotic Picea abies , Hebeloma crustuliniforme associations to gain new insights into the mechanisms of detoxification of these two metals in Norway spruce seedlings. The mycorrhizal seedlings were exposed in growth pouches to either 1 mM Cd or 2 mM Zn for 5 weeks. The microanalytical data revealed that two distinct Cd- and Zn-binding mechanisms are involved in cellular compartmentation of Cd and Zn in the mycobiont. Whereas extracellular complexation of Cd occurred predominantly in the Hartig net hyphae, both extracellular complexation and cytosolic sequestration of Zn occurred in the fungal tissue. The vacuoles were presumed not to be a significant pool for Cd and Zn storage. Cadmium was almost exclusively localized in the cell walls of the Hartig net (up to 161 mmol kg,1 DW) compared with significantly lower concentrations in the cell walls of mantle hyphae (22 mmol kg,1 DW) and in the cell walls of cortical cells (15 mmol kg,1 DW). This suggests that the apoplast of the Hartig net is a primary accumulation site for Cd. Zinc accumulated mainly in the cell walls of the mantle hyphae (111 mmol kg,1 DW), the Hartig net hyphae (130 mmol kg,1 DW) and the cortical cells (152 mmol kg,1 DW). In addition, Zn occurred in high concentrations in the cytoplasm of the fungal mantle hyphae (up to 164 mmol kg,1 DW) suggesting that both the cell walls and the cytoplasm of fungal tissue are the main accumulation sites for Zn in P. abies resulting in decreased Zn transfer from the fungus to the root. [source]