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PubMed1978

Characterization of the bacterial flora associated with root systems of Pinus contorta var. latifolia.

Root systems of young and mature lodgepole pine (Pinus contorta Dougl. var. latifolia Englem.) were removed from forest stands and the associated aerobic bacterial flora isolated. Characterization of rhizoplane and control soil isolates from these tree root systems demonstrated differences from that reported for agricultural crops. Ammonifying, proteolytic, and amylolytic organisms were proportionately reduced within the rhizoplane. The rhizoplane organisms grew more slowly than the control soil isolates, although they responded in greater numbers to the addition of an amino acid supplement to the growth media. The rhizoplane organisms also showed an increased ability to solubilize phosphate. The chitinolytic organisms were suppressed within the rhizoplane of the mature tree but were stimulated by the young trees. With this exception, the rhizoplane microflora of older and younger trees were similar.

Ammonia↗
PubMed1981

Studies on the descendancy of four populations of Koekelaere pines: Pinus nigra Arnold, subsp. laricio (Poiret) Maire, cv. Koekelaere. II. Heritability as a function of parental age.

The variations of heritability as a function of parental age are studied in Koekelaere pines [Pinus nigra Arnold, laricio (Poiret) Maire, cv. Koekelaere]. The age of the parental trees varies between 26 and 101 years. 16 different traits are analysed. It is shown that heritability does not vary as a function of parental age. These results are discussed in relation with the problems of ageing in trees and of the theories of ageing.

Aging↗
PubMed1990

IgE-binding proteins from pine (Pinus radiata D. Don) pollen: evidence for cross-reactivity with ryegrass (Lolium perenne).

A complex mixture of pine (Pinus radiata D. Don) pollen proteins are rapidly released into aqueous solutions. IgE-binding proteins have been identified in these extracts using combined SDS-PAGE immunoblotting techniques. These IgE-binding proteins were detected using atopic patient and commercial pooled human sera known to be high in ryegrass-specific IgE. Enzyme-immunoassay inhibition studies revealed that leached P. radiata pollen proteins could partially inhibit serum IgE binding to ryegrass RAST discs thus providing preliminary evidence for allergen cross-reactivity between these two unrelated species.

Antigens, Differentiation↗
PubMed1996

Accumulation of benzoic acid in suspension cultured cells of Pinus thunbergii Parl. in response to phenylacetic acid administration.

The generation and accumulation of both benzoic acid (BA) and its conjugates were induced in suspension cultured cells of Pinus thunbergii by administering either phenylacetic acid (PA), a toxic metabolite of Bacillus cereus (strain HY-3) accompanying the pine wood nematode, or a lyophilized culture supernatant of this bacterium. BA conjugates reached their maximal levels in quantity two days after the administration and then decreased gradually until the 14th day, while BA increased significantly throughout this period. This pattern is similar to that in 3-year-old pine trees treated with PA, suggesting that the pathological reaction of pine tissues to the PA toxin might be involved in the pathogenesis mechanism for the pine wilt disease.

Animals↗
PubMedDate not supplied

Benzoic acid accumulation in the Pinus thunbergii callus inoculated with the pine wood nematode, Bursaphelenchus xylophilus.

Phenylacetic acid (PA), a phytotoxic product of the bacteria accompanying the virulent nematode isolate OKD-3 was detected in the callus of Pinus thunbergii after inoculation with the nematode. The amount of PA detected was large enough to induced the formation and accumulation of benzoic acid (BA) and its conjugates in the callus. These results further support the hypotheses that PA is the pathogenic toxin and that the PA-producing bacterial strains accompanying the pathogenic nematode are the genuine pathogens of the pine wilt disease.

Animals↗
PubMed1996

Nucleotide sequence of the internal transcribed spacers and 5.8S region of ribosomal DNA in Pinus pinea L.

The nucleotide sequence of the first internal transcribed spacer (ITS1) belonging to different ribosomal RNA genes from Pinus pinea are reported. The analyzed ITS1 can be distinguished on the basis of their length, being one 2631 bp and the other 271 bp long. Nucleotide comparison of these regions did not show appreciable sequence homology. The larger ITS1 contains five tandem arranged subrepeats with size ranging between 219 bp and 237 bp. The nucleotide sequence of the 5.8S and the ITS2 regions belonging to the larger ribosomal RNA gene are also reported.

Base Sequence↗
PubMedDate not supplied

Radical modulation activity of pine cone extracts of Pinus elliottii var. Elliottii.

The radical modulation activity of lignins prepared from the cone of Pinus elliottii var. Elliottii was investigated, using ESR spectroscopy. These lignins produced radical(s) under alkaline conditions, and the radical intensity was increased with increasing pH. Lower concentrations of lignins slightly reduced the radical intensity of sodium ascorbate, whereas higher concentrations of lignins enhanced both the radical intensity and cytotoxic activity of sodium ascorbate. Lignins effectively scavenged superoxide anion, produced by hypoxanthine-xanthine oxidase reaction. Elliottii lignins significantly inhibited the human immunodeficiency virus (HIV)-induced cytopathic effect, in similar fashions to other natural, commercial and synthetic lignins. Pretreatment of mice with lignins significantly protected them from the lethal infection with E. coli. Crude alkaline extracts of Elliottii pine cone displayed similar magnitude of activity with lignins. These data further supports the medicinal efficacy of plant extracts.

Animals↗
PubMed2000

How accessible are receptive megastrobili to pollen? the example of jack pine (Pinus banksiana).

We examined the effects of wind speeds on pollen capture by megastrobili of jack pine (Pinus banksiana). We found that, when wind speed increased from 1.3 to 7.5 m/s, the relative capture efficiency (E(r)) did not change significantly (P ≤ 0.206) and remained below 12%. However, total capture rates increased linearly with wind speed and atmospheric pollen density. Because theoretical models of capture efficiency predict the E(r) to increase to ∼80% asymptotically, our findings suggest that receptive megastrobili are equally adept at capturing pollen at all naturally occurring wind speeds.

Journal Article↗
PubMed2000

Effects of dietary maritime pine (Pinus pinaster)-seed oil on high-density lipoprotein levels and in vitro cholesterol efflux in mice expressing human apolipoprotein A-I.

Maritime pine (Pinus pinaster)-seed oil contains two Delta5 unsaturated polymethylene interrupted fatty acids (all cis-5,9, 12-18:3 and all cis-5,11,14-20:3 acids) one of which resembles eicosapentaenoic acid. The goal of the present study was to test whether maritime pine-seed oil consumption affects HDL and apolipoprotein (Apo) A-I levels as well as the ability of serum to promote efflux of cholesterol from cultured cells. To this end, wild type (WT) non-transgenic mice and transgenic mice expressing human ApoA-I (HuA-ITg) were fed on isoenergetic diet containing either 200 g maritime pine-seed oil/kg or 200 g lard/kg for 2 weeks. WT and HuA-ITg mice fed maritime pine-seed oil had lower cholesterol, HDL-cholesterol, LDL-cholesterol and HuA-ITg mice had lower human ApoA-I than those fed lard. The differences in cholesterol (P < 0.0001) and HDL-cholesterol (P < 0.003) levels between mice fed on the two diets were more pronounced in the HuA-ITg than in the WT mice. The ability of HuA-ITg serum to promote cholesterol efflux in cultured cells was greater (P < 0.008) than that of WT animals. However, the maritime pine-seed oil diet was associated with lower (P < 0.005) in vitro cholesterol efflux ability than the lard diet in both mice genotypes. This suggests a negative effect of the maritime pine-seed oil on reverse cholesterol transport. Cholesterol efflux was correlated with serum free or esterified cholesterol and phospholipid levels. The slope of the regression line was smaller in the HuA-ITg than in the WT mice indicating that overexpression of human ApoA-I reduces the negative impact of maritime pine-seed oil on cholesterol efflux. In conclusion, maritime pine-seed oil diet lowers HDL-cholesterol and diminishes in vitro cholesterol efflux. This potentially detrimental effect is attenuated by overexpression of human ApoA-I in mice.

Analysis of Variance↗
PubMed2000

Allozyme diversity and population genetic structure of Pinus densata Master in northwestern Yunnan, China.

We investigated the levels and patterns of genetic diversity of Pinus densata Master in Yunnan. Horizontal starch-gel electrophoresis was performed on macrogametophytes collected from nine populations in northwestern Yunnan, China. Compared with other gymnosperm species, P. densata has higher mean values for all measures of genetic diversity. Allozyme polymorphism (0.99 criterion) was 97.0% and 71.4% at the species and population levels, respectively. The average number of alleles per locus was 3.1 and 2.0 at the species and population levels. Mean expected heterozygosity was substantially higher in P. densata than average values investigated for other gymnosperms both at the population (Hep = 0.174 +/- 0.031) and at the species (Hes = 0.190) levels. Of the total genetic variation, less than 12% was partitioned among populations (GST = 0.112). Our allozyme survey supports the suggestion that the observed higher diversity in P. densata may be attributed partly to its hybrid origin between two genetically distinct species, P. yunnanensis and P. tabulaeformis. In addition, we suggest that introgression would give rise to the increase in genetic diversity occurring in P. densata.

Alleles↗
PubMed2000

Morphological variation of Pinus flexilis (Pinaceae), a bird-dispersed pine, across a range of elevations.

Limber pine (Pinus flexilis James) grows across a wider range of elevations than any other tree species in the central Rockies, from ∼1600 m at Pawnee Buttes to >3300 m at Rollins Pass. In this study we investigated two possible explanations for limber pine's success across a broad range of elevations: (1) the sites on which it is found, although separated by >1000 m elevation, may not be very different with respect to environmental factors that affect tree growth, and (2) limber pine growth is insensitive to environmental factors that change with elevation. We compared site characteristics of 12 limber pine stands at elevations ranging from 1630 to 3328 m as well as the growth and morphology of trees in each of these stands. Mean daily air temperature in July decreased linearly with the elevation of the site from 22.8° to 12.6°C. The growth and morphology of limber pine leaves, shoots, and trees were, in general, not related to the elevation or July mean air temperature of the sites. There was, however, a significant decrease in stomatal density with increasing elevation, which may be an acclimational response to restrict water loss at high elevations. Our data suggest that the fundamental and realized niche of limber pine is broad with respect to air temperature. In light of the high gene flow and only slight genetic differentiation among populations of species with bird-dispersed seeds, such as limber pine, it is especially unusual to see similar growth throughout an environmental gradient. Physiological and anatomical plasticity or wide physiological tolerance ranges may enable limber pine to uncouple its growth from its environment.

Journal Article↗
PubMed2001

Differential stress responses of antioxidative systems to drought in pendunculate oak (Quercus robur) and maritime pine (Pinus pinaster) grown under high CO(2) concentrations.

Maritime pine (Pinus pinaster), a drought-avoiding species, contained 2--4-fold lower activities of superoxide dismutase, ascorbate peroxidase, catalase, dehydroascorbate reductase, and glutathione reductase than pendunculate oak (Quercus robur), a drought-tolerant species. The levels of ascorbate, monodehydroascorbate radical reductase activity, and glutathione in pine needles were similar to those in oak leaves. In both species the development of drought stress, characterized by decreasing predawn water potentials, caused gradual reductions in antioxidant protection, increased lipid peroxidation, increased oxidation of ascorbate and glutathione and in pine also significant loss in soluble proteins and carotenoids. These results support the idea that increased drought-tolerance in oak as compared with pine is related to increased biochemical protection at the tissue level. To test the hypothesis that elevated CO(2) ameliorated drought-induced injury, young oak and pine trees acclimated to high CO(2) were subjected to drought stress. Analysis of plots of enzymatic activities and metabolites against predawn water potentials revealed that the drought stress-induced decreases in antioxidant protection and increases in lipid peroxidation were dampened at high CO(2). In pine, protein and pigment degradation were also slowed down. At high CO(2), superoxide dismutase activities increased transiently in drought-stressed trees, but collapsed in pine faster than in oak. These observations suggest that the alleviation of drought-induced injury under elevated CO(2) is related to a higher stability of antioxidative enzymes and an increased responsiveness of SOD to stressful conditions. This ameliorating mechanism existed independently from the effects of elevated CO(2) on plant water relations and is limited within a species-specific metabolic window.

Antioxidants↗
PubMed2001

Construction of a framework map in Pinus contorta subsp. latifolia using random amplified polymorphic DNA markers.

We report on the construction of the first random amplified polymorphic DNA (RAPD) framework map in Pinus contorta subsp. latifolia. Genomic DNA of haploid megagametophytes from 90 open-pollinated seeds originating from a single tree were amplified with 840 random decamer oligonucleotide primers by the polymerase chain reaction. Three-hundred twenty-eight RAPD markers with fragment sizes that ranged between 260 and 3080 base pairs were found segregating at 110 random decamer oligonucleotide primers. Of these 328 RAPD markers, 148 were mapped to 16 framework linkage groups and 77 were mapped as accessory markers onto the framework linkage groups, on a support interval of minimal LOD score of 3. The 16 framework maps cover a distance of 2287 cM. The estimate of genome size was 2407 cM with a 95% confidence interval of 2304-2459 cM.

Base Sequence↗
PubMed2001

Spatial genetic structure of allozyme polymorphisms within populations of Pinus Strobus (Pinaceae).

The population structure of genetic variation for four allozyme loci was investigated for two populations (one old growth, OG, and the other logged, SS) of eastern white pine (Pinus strobus). Both seedlings and reproductive adults were studied for both study populations. Spatial autocorrelation statistics were used to examine the distribution of allozyme polymorphisms. The spatial genetic structure in adults of population OG indicated that individual genotypes were distributed in a structured, isolation-by-distance manner, consistent with observed levels of pollen and seed dispersal. In contrast, adult genotypes in population SS were nearly randomly distributed, probably as a result of logging. Nonetheless, spatial structuring of genotypes of seedlings occurred at both sites, indicating the power of limited seed flow, as well as temporal Wahlund effects, to create structure. None of four loci in both seedling populations showed a significant departure from Hardy-Weinberg proportions, whereas one and two significant deviations were found for loci in the two respective adult populations. These departures may be attributed to episodic reproductive events.

Journal Article↗
PubMed2001

A comparative study of glutathione and ascorbate metabolism during germination of Pinus pinea L. seeds.

The ascorbate and glutathione systems have been studied during the first stages of germination in orthodox seeds of the gymnosperm Pinus pinea L. (pine). The results indicate that remarkable changes in the content and redox balance of these metabolites occur in both the embryo and endosperm; even if with different patterns for the two redox pairs. Dry seeds are devoid of the ascorbate reduced form (ASC) and contain only dehydroascorbic acid (DHA). By contrast, glutathione is present both in the reduced (GSH) and in the oxidized (GSSG) forms. During imbibition the increase in ASC seems to be mainly caused by the reactivation of its biosynthesis. On the other hand, the GSH rise occurring during the first 24 h seems to be largely due to GSSG reduction, even if GSH biosynthesis is still active in the seeds. The enzymes of the ascorbate--glutathione cycle also change during germination, but in different ways. ASC peroxidase (EC 1.11.1.11) and glutathione reductase (EC 1.6.4.2) activities progressively rise both in the embryo and in endosperm. These changes are probably required for counteracting production of reactive oxygen species caused by recovery of oxidative metabolism. The two enzymes involved in the ascorbate recycling, ascorbate free radical (AFR) reductase (EC 1.6.5.4) and DHA reductase (EC 1.8.5.1), show different behaviour: the DHA reductase activity decreases, while that of AFR reductase remains unchanged. The relationship between ascorbate and glutathione metabolism and their relevance in the germination of orthodox seeds are also discussed.

Antioxidants↗
PubMed1976

Effect of extraction of histones and their reconstitution on [3H] actinomycin D binding to isolated nuclei of the root of Pinus silvestris.

The purpose of the study presented was to investigate the effect of the extraction of histones on the template activity of DNA, measured by the autoradiographically evaluated intensity of [3H]actinomycin D ([3H]AMD) binding. The study was carried out on nuclei isolated from the root meristem of Pinus silvestris. Histones were removed selectively from them and reconstituted in the nuclei deprived of these proteins. The greatest rise in radioactivity was found after the extraction of the arginine fraction and that of lysine-rich and moderately lysine-rich fractions removed together, whereas the extraction of the lysine-rich fraction does not cause such a considerable increase in radioactivity. The reconstitution of particular histone fractions induced a fall in radioactivity to the level of controls in all the cases examined. No [3H]AMD binding to the nucleolus was found. The extraction of lysine histones results in the decondensation of chromatin and their reconstitution in the formation of complexes of compact chromatin.

Binding Sites↗
PubMedDate not supplied

Suppression by a pine cone extract of Pinus parviflora Sieb et Zucc of mammary tumour virus in milk of mice.

The intravenous or the oral administration of a pine cone extract of Pinus parviflora Sieb et Zucc (Fr VI) and the related synthetic agent (DHP-FA) to lactating SHN mice prevented an increase of milk levels of mouse mammary tumour virus (MMTV) from day 7 to day 14 of lactation. Furthermore, Fr VI decreased the MMTV level at the 2nd lactation compared to the 1st lactation. This is the first report on the inhibition of milk MMTV of mice in the in vivo system.

Administration, Oral↗