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At least 55 records · Page 3Linked to original sources
PubMed2006

Suillus variegatus causes significant changes in the content of individual polyamines and flavonoids in Scots pine seedlings during mycorrhiza formation in vitro.

Changes in the concentrations of individual flavonoids and polyamines (PAs) in Scots pine (Pinus sylvestris L.) cotyledonary seedlings were studied during the establishment of an ectomycorrhizal (ECM) symbiosis with two Suillus variegatus strains in vitro. Both flavonoids and PAs were analysed after 3, 7, and 14 d in dual culture, and changes in concentrations were compared with growth of the seedlings. Both S. variegatus strains caused similar responses in Scots pine seedlings. Free putrescine accumulated immediately but only transiently after inoculation. This was followed by continuous accumulation of PA conjugates in needles and stems, and free spermidine and spermine in roots, which was accompanied by mycorrhiza formation and improved growth. The fungi induced lateral root formation and main root and primary needle elongation. Inoculation caused no qualitative changes in flavonoid composition, while quantitative changes in flavonols, catechins, and condensed tannins were observed in shoots during mycorrhiza formation. These results indicate that in this in vitro system conjugated PAs and specific flavonoids, generally related to the plant's defence reactions, did not play a major role in the regulation of the establishment of the ectomycorrhizal (ECM) symbiosis in Scots pine roots. The results also clearly show that positive growth responses in shoots and roots due to S. variegatus were supported by different and highly specific changes in the synthesis of both primary and secondary metabolites in these parts of the seedling.

Basidiomycota↗
PubMed2005

Seasonal variations in location and population structure of endophytes in buds of Scots pine.

We studied the location and distribution of a bacterial isolate, a Mycobacterium sp., in buds of Scots pine (Pinus sylvestris L.). Using a probe specific for the 16S rRNA of the Mycobacterium sp., the bacterium was found by in situ hybridization in the meristematic tissues of 40% of all bud samples examined. Because we had previously found other bacterial and fungal endophytes in the meristematic tissues of Scots pine buds, we studied their occurrence in buds during shoot development and dormancy. Using probes targeted to the 16S or 18S rRNA of the endophytes Mycobacterium sp., Methylobacterium spp., Pseudomonas spp. and Rhodotorula minuta, endophytes were found in association with growing tissues, with Methylobacterium spp. being the dominant species. Endophytes were detected in abundance before elongation or differentiation of a bud, but once a tissue was fully developed, endophytes were no longer detected. Metabolic activity of the endophytes was suppressed at the onset of, and during, dormancy of Scots pine, but recovered before the following growing season.

In Situ Hybridization↗
PubMedDate not supplied

The haggis tolerance test in Scots and Sassenachs.

To find out if the Scottish national dish, haggis, contributes to the high incidence of coronary heart disease in Scotland the lipaemic effect of a meal of 200 g of haggis was measured in six Scottish and 10 Sassenach men. The Scots had higher fasting cholesterol and triglyceride concentrations and a lower proportion of high density lipoprotein cholesterol than the Sassenachs. Four subjects were found to have hyperlipoproteinaemia, which had been unrecognised previously. Serum cholesterol concentrations did not change after haggis was eaten (mean dose 2.6 g/kg body weight). Serum concentrations of triglycerides increased by 51% at 90 minutes in the Sassenachs but were unaltered in the Scots. There were no serious adverse effects. This study shows that Scots have higher lipid concentrations than Sassenachs but seem to be resistant to the lipaemic effect of haggis. The haggis tolerance test may be useful in Sassenachs.

Adult↗
PubMed1990

Type I and type II genes for the chlorophyll a/b-binding protein in the gymnosperm Pinus sylvestris (Scots pine): cDNA cloning and sequence analysis.

A cDNA library was constructed from mRNA prepared from light-treated seedlings of Scots pine (Pinus sylvestris L.) and cDNAs for the chlorophyll a/b-binding protein LHC-II were identified using a pea gene as the heterologous probe. Three cDNA clones were sequenced. The deduced amino acid sequences of two of the genes corresponded to Type I and one to Type II LHC-II proteins which were ca. 90% homologous to their angiosperm counterparts. The transit peptides of the Scots pine preLHC-II showed features common to angiosperm transit peptides. The three cDNAs had a 70 to 75% preference for G + C in the third base position. CpG and GpC profiles and degenerate codon position bias suggested that two of the corresponding genes lie within CpG islands.

Amino Acid Sequence↗
PubMed1987

Electrophoretic analysis of genetic linkage in Scots pine (Pinus sylvestris L.).

Eighty megagametophytes from each of 24 Scots pines (Pinus sylvestris L.) were subjected to horizontal starch gel electrophoresis. The trees were from crosses among widely separated provenances, and each was polymorphic for 8 to 14 loci. Evidence for linkage among 275 two-locus combinations was tested using chi-square analysis. Data from different trees were pooled to calculate map distances for the species. Nineteen of the twenty-nine loci tested were linked in one of six groups; the groups varied in size from two to seven loci. Similarities in linkage relationships among Scots pine, other pines, and other species within the Pinaceae support karyological research that suggests extensive conservation of the conifer genome.

Electrophoresis, Starch Gel↗
PubMed2006

Comparison of REML and Gibbs sampling estimates of multi-trait genetic parameters in Scots pine.

Multi-trait (co)variance estimation is an important topic in plant and animal breeding. In this study we compare estimates obtained with restricted maximum likelihood (REML) and Bayesian Gibbs sampling of simulated data and of three traits (diameter, height and branch angle) from a 26-year-old partial diallel progeny test of Scots pine (Pinus sylvestris L.). Based on the results from the simulated data we can conclude that the REML estimates are accurate but the mode of posterior distributions from the Gibbs sampling can be overestimated depending on the level of the heritability. The mean and median of the posteriors were considerably higher than the expected values of the heritabilities. The confidence intervals calculated with the delta method were biased downwardly. The highest probability density (HPD) interval provides a better interval estimate, but could be slightly biased at the lower level. Similar differences between REML and Gibbs sampling estimates were found for the Scots pine data. We conclude that further simulation studies are needed in order to evaluate the effect of different priors on (co)variance components in the genetic individual model.

Analysis of Variance↗
PubMed2006

Low nitrification rates in acid Scots pine forest soils are due to pH-related factors.

In a previous study, ammonia-oxidizing bacteria (AOB)-like sequences were detected in the fragmentation layer of acid Scots pine (Pinus sylvestris L.) forest soils (pH 2.9-3.4) with high nitrification rates (>11.0 microg g-1 dry soil week-1), but were not detected in soils with low nitrification rates (<0.5 microg g-1 dry soil week-1). In the present study, we investigated whether this low nitrification rate has a biotic cause (complete absence of AOB) or an abiotic cause (unfavorable environmental conditions). Therefore, two soils strongly differing in net nitrification were compared: one soil with a low nitrification rate (location Schoorl) and another soil with a high nitrification rate (location Wekerom) were subjected to liming and/or ammonium amendment treatments. Nitrification was assessed by analysis of dynamics in NH4+-N and NO3- -N concentrations, whereas the presence and composition of AOB communities were assessed by polymerase chain reaction-denaturing gradient gel electrophoresis and sequencing of the ammonia monooxygenase (amoA) gene. Liming, rather than ammonium amendment, stimulated the growth of AOB and their nitrifying activity in Schoorl soil. The retrieved amoA sequences from limed (without and with N amendment) Schoorl and Wekerom soils exclusively belong to Nitrosospira cluster 2. Our study suggests that low nitrification rates in acidic Scots pine forest soils are due to pH-related factors. Nitrosospira cluster 2 detected in these soils is presumably a urease-positive cluster type of AOB.

Bacteria↗
PubMed2001

Photosynthetic electron transport adjustments in overwintering Scots pine (Pinus sylvestris L.).

As shown before [C. Ottander et al. (1995) Planta 197:176-183], there is a severe inhibition of the photosystem (PS) II photochemical efficiency of Scots pine (Pinus sylvestris L.) during the winter. In contrast, the in vivo PSI photochemistry is less inhibited during winter as shown by in vivo measurements of deltaA820/A820 (P700+). There was also an enhanced cyclic electron transfer around PSI in winter-stressed needles as indicated by 4-fold faster reduction kinetics of P700+. The differential functional stability of PSII and PSI was accompanied by a 3.7-fold higher intersystem electron pool size, and a 5-fold increase in the stromal electron pool available for P700+ reduction. There was also a strong reduction of the QB band in the thermoluminescence glow curve and markedly slower Q-A re-oxidation in needles of winter pine, indicating an inhibition of electron transfer between QA and QB. The data presented indicate that the plastoquinone pool is largely reduced in winter pine, and that this reduced state is likely to be of metabolic rather than photochemical origin. The retention of PSI photochemistry, and the suggested metabolic reduction of the plastoquinone pool in winter stressed needles of Scots pine are discussed in terms of the need for enhanced photoprotection of the needles during the winter and the role of metabolically supplied energy for the recovery of photosynthesis from winter stress in evergreens.

Adaptation, Physiological↗
PubMed2002

Pisolithus tinctorius promotes germination and forms mycorrhizal structures in Scots pine somatic embryos in vitro.

The results of the present study show that inoculation with the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch potentially enhances the germination of Scots pine (Pinus sylvestris L.) somatic embryos in vitro. Stimulation by Pisolithus tinctorius was only observed in the absence of direct contact between the symbionts; mature embryos were not sufficiently robust for balanced interaction with the fungus on half-strength DCR medium. Subsequently, on MMN medium with a reduced sugar concentration, direct contact between somatic embryo-derived plants and the fungus resulted in in vitro formation of mycorrhiza. Ex vitro inoculation also improved adaptation of the somatic embryo-derived plants, even though mycorrhizal structures were not observed. The reactions to Pisolithus tinctorius varied between different Scots pine cell lines both in vitro and ex vitro.

Basidiomycota↗
PubMed2003

Abundance, diversity, and vitality of mycorrhizae of Scots pine (Pinus sylvestris L.) in lignite recultivation sites.

Scots pine (Pinus sylvestris L.) stands cover large areas in the Lusatian and the Middle German lignite mining districts. Due to adverse chemical substrate conditions, the root systems of the trees are restricted to the ameliorated top-spoil and the organic forest floor layers. To investigate functioning of fine root systems under the prevailing site factors, we studied mycorrhizal colonization rate and frequency as well as mycorrhizal diversity, vitality and growth phases in Scots pine ecosystems along a chronosequence in both mining districts. Mycorrhizal rate was close to 100% in both districts. Mycorrhizal abundance was higher in the organic forest floor layer than the mineral soil layer. In total, 25 morphotypes were recorded. Diversity differed between the districts. The mycorrhizae of Amphinema byssoides, Tuber puberulum, Pinirhiza discolor, Pinirhiza cf. bicolorata and E-type were present in both mining areas. These morphotypes are typical of nutrient-rich soils with high pH values. Compared with the undisturbed sites, vitality of mycorrhizae was very high at the test sites on spoil substrate, correlating with the high growth dynamics of mycorrhizae at recultivation sites. A relatively high carbon flow to the mycorrhizal root systems at these sites seems likely. Thus, mycorrhizal root systems are able to cope with the ameliorated top-spoil and the organic layer. The main reason for the adaptation is the large number of ectomycorrhizal fungal species available in this area where Pinus sylvestris is indigenous.

Biodiversity↗
PubMed2004

Use of Scots pine seedling roots as an experimental model to investigate gene expression during interaction with the conifer pathogen Heterobasidion annosum (P-type).

The root-rot fungus Heterobasidion annosum is a major pathogen of woody trees in temperate regions of the world. In this study, seedling root of Scots pine was used as an experimental model to investigate gene expression in conifer trees during challenge with H. annosum. Initial cellular and histochemical studies have established the systems and indicated the key sequence of events during the infection process. Also, to correlate histochemical observations with the time-dependent pattern of events in host gene expression, a transcriptome profiling of a selected set of host genes from a pine-root subtraction cDNA library was conducted. Differential screening of the subset of genes arrayed on nylon membrane with cDNA probes made from seedling roots infected for 1, 3, 7 and 15 days revealed a number of up-regulated genes [disease-resistance gene analog, antimicrobial peptide (AMP) gene homolog etc.] following inoculation. The results also showed strong expression of genes involved in cell defense and protein synthesis at the early stages of the infection (3-7 days) with a decline at late stages of infection (15 days). The decline in expression of key defense genes at late stages of infection correlated well with the period of vascular colonization and subsequent loss of root turgor. Northern analyses with two of the major induced genes (AMP homolog and disease-resistance gene analog) indicated a several-fold increase in host gene expression following infection. In addition, a particular single gene (thaumatin-like protein) was consistently expressed throughout the four sampling periods of the experiment. BlastX analyses revealed that the Scots-pine thaumatin-like gene shared 51-77% sequence homology with other thaumatin-like proteins in GenBank. The importance of these results in tree defense and use of conifer seedling root in host-parasite interaction in forest trees is discussed.

Amino Acid Sequence↗
PubMed1988

Height growth of different European Scots pine Pinus sylvestris L. Provenances in a heavily polluted and a control environment.

Results are presented of height measurements and degree of needle injury on five-year-old plants of Scots pine (Pinus sylvestris L.) growing near a phosphate fertiliser plant that emits SO(2) and fluorides. The populations of Scots pine represented in this experiment originate from 11 countries and were substantially differentiated in height growth and extent of needle necroses. Those populations which grew most rapidly were found to be the most sensitive to pollutant injury. The least productive provenances from the north of the range (Sweden, USSR) are at the same time characterized by lowest decline in height growth, lowest mortality and least extensive necroses. It is proposed that gene banks be established for the best genotypes likely to be eliminated in the heavily polluted conditions of Poland today.

Journal Article↗
PubMed2006

Enantiomeric monoterpene emissions from natural and damaged Scots pine in a boreal coniferous forest measured using solid-phase microextraction and gas chromatography/mass spectrometry.

In order to develop a valuable method for accurate screening of biogenic emissions from undisturbed living plants or for plant-insect interactions, solid-phase microextraction (SPME) has been combined with dynamic branch enclosure cuvettes and enantioselective GC/MS. The study was conducted at Hyytiälä forest station, Finland within a boreal coniferous forest dominated by Scots pine (Pinus sylvestris). The SPME method was optimized for monoterpenes by testing three fibre coatings: polydimethylsiloxane (PDMS), polydimethylsiloxane/divinylbenzene (PDMS/DVB) and carbowax/divinylbenzene (CW/DVB) and determining the optimum exposure time. The PDMS/DVB fibre was found to be most suitable and was used to characterize emissions of P. sylvestris enclosed in dynamic branch enclosure cuvettes by exposure for 1 min followed by desorption and separation on a beta-cyclodextrin column installed in the GC/MS oven. Dynamic cuvette measurements have been compared to static headspace SPME samples of the emission of detached needles from the same tree species and a portable dynamic air sampler (PDAS)-SPME for sampling the ambient air around the same trees. The method developed has allowed an accurate characterization of the gaseous emission of P. sylvestris and the identification of 17 isoprenoids comprising chiral and achiral monoterpenes. Two chemotypes of Scots pine can be differentiated through their emission of (+)-delta-3-carene. While SPME-dynamic cuvette, portable dynamic sampler and absorbent results agreed well, significant differences in enantiomeric ratios were observed in natural emissions and those of damaged leaves. Therefore, in enantioselective studies of plant-insect and/or plant-plant interactions, the two enantiomers of a given monoterpene should be treated as two separate substances.

Finland↗
PubMed2005

Changes in the concentrations of phenolics and photosynthates in Scots pine (Pinus sylvestris L.) seedlings exposed to nickel and copper.

Studies were done on the effects of elevated soil concentrations of copper (Cu) and (Ni) on foliar carbohydrates and phenolics in Scots pine (Pinus sylvestris L.). Four year-old seedlings were planted in pots filled with metal-treated mineral forest soil in early June. The experimental design included all combinations of four levels of Cu (0, 25, 40 and 50 mg kg(-1) soil dw) and Ni (0, 5, 15 and 25 mg kg(-1) soil dw). Current year needles were sampled for soluble sugar, starch and phenolics at the end of September. Ni increased sucrose concentration in the needles, indicating disturbances in carbohydrate metabolism. Trees exposed to Ni had higher concentrations of condensed tannins compared with controls. In contrast, concentrations of several other phenolic compounds decreased when seedlings were exposed to high levels of Cu or to a combination of Ni and Cu. The results suggest that concentrations of phenolics in Scots pine needles vary in their responses to Ni and Cu in the forest soil.

Carbohydrates↗
PubMed2005

Are N and S deposition altering the mineral composition of Norway spruce and Scots pine needles in Finland?

Data from a large-scale foliar survey were used to calculate the extent to which N and S deposition determined the mineral composition of Scots pine and Norway spruce needles in Finland. Foliar data were available from 367 needle samples collected on 36 plots sampled almost annually between 1987 and 2000. A literature study of controlled experiments revealed that acidifying deposition mediates increasing N and S concentrations, and decreasing Mg:N and Ca:Al ratios in the needles. When this fingerprint for N and S elevated deposition on tree foliage was observed simultaneously with increased N and S inputs, it was considered sufficient evidence for assuming that acidifying deposition had altered the mineral composition of tree needles on that plot in the given year. Evidence for deposition-induced changes in the mineral composition of tree foliage was calculated on the basis of a simple frequency model. In the late eighties the evidence was found on 43% of the Norway spruce and 27% of Scots pine plots. The proportion of changed needle mineral composition decreased to below 8% for both species in the late nineties.

Acid Rain↗
PubMed2005

Seasonal patterns of ascorbate in the needles of Scots Pine (Pinus sylvestris L.) trees: correlation analyses with atmospheric O3 and NO2 gas mixing ratios and meteorological parameters.

In the present field study the role of ascorbate in scavenging the harmful atmospheric trace gases O3 and NO2 was examined. For this purpose ascorbate contents were determined in needles of adult Scots pine trees (Pinus sylvestris L.) during three consecutive years. Ascorbate contents were correlated with ambient tropospheric O3 and NO2 concentrations and with meteorological parameters. The results showed a strong correlation of atmospheric O3 but not of atmospheric NO2 concentrations with the apoplastic content of ascorbate during the seasonal course. Ascorbate contents in needle extracts did not correlate with ambient trace gas concentrations. In the apoplastic space, but not in needle extracts ascorbate contents correlate highly significantly with global radiation. From these results it is assumed that apoplastic ascorbate in Scots pine needles is adapted to the actual atmospheric O3 concentration to mediate immediate detoxification of O3, while the atmospheric O3 concentration itself is largely dependent on light intensity.

Air Pollutants↗
PubMed2006

Spermidine and the ectomycorrhizal fungus Pisolithus tinctorius synergistically induce maturation of Scots pine embryogenic cultures.

Exogenous spermidine (Spd) and the ectomycorrhizal (ECM) fungus Pisolithus tinctorius (Pers.) Coker and Couch had a synergistic effect on the maturation of Scots pine (Pinus sylvestris L.) somatic embryos. Induced maturation was expressed as a higher number of cell masses able to form embryos and a greater number of embryos formed per cell mass. In contrast, treatment with P. tinctorius alone on the hormone-free medium resulted in the lowest embryo-forming capacity. Retarded proliferation growth appeared to be required for maturation, but did not explain the synergistic effect of the fungus and exogenous Spd. Simultaneous treatment did not result in lower concentrations of putrescine (Put), Spd or spermine (Spm) in the embryogenic cell masses relative to the separate treatments. Our study is the first report on the use of a specific ECM fungus to induce maturation of somatic embryos, and it indicates that P. tinctorius was able to modify the maturation media in a way that, together with exogenous Spd, positively affected embryogenic cultures of Scots pine. Our study also shows that it is possible to enhance plant development other than root formation by using specific ECM fungi.

Basidiomycota↗
PubMed2004

A UV resonance Raman (UVRR) spectroscopic study on the extractable compounds in Scots pine (Pinus sylvestris) wood. Part II. Hydrophilic compounds.

Hydrophilic extracts of Scots pine (Pinus sylvestris) heartwood and sapwood and a solid Scots pine knotwood sample were studied by UV resonance Raman spectroscopy (UVRRS). In addition, UVRR spectra of two hydrophilic model compounds (pinosylvin and chrysin) were analysed. UV Raman spectra were collected using 244 and 257 nm excitation wavelengths. The chemical composition of the acetone:water (95:5 v/v) extracts were also determined by gas chromatography. The aromatic and oleophilic structures of pinosylvin and chrysin showed three intense resonance enhanced bands in the spectral region of 1649-1548 cm(-1). Pinosylvin showed also a relatively intense band in the aromatic substitution region at 996 cm(-1). The spectra of the heartwood acetone:water extract showed many bands typical of pinosylvin. In addition, the extract included bands distinctive for resin and fatty acids. The sapwood acetone:water extract showed bands due to oleophilic structures at 1655-1650 cm(-1). The extract probably also contained oligomeric lignans because the UVRR spectra were in parts similar to that of guaiacyl lignin. The characteristic band of pinosylvin (996 cm(-1)) was detected in the UVRR spectrum of the resin rich knotwood. In addition, several other bands typical for wood resin were observed, which indicated that the wood resin in the knotwood was resonance enhanced even more than lignin.

Acetone↗