Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| effects of air pollutants on the composition of stable carbon isotopes, deltac, of leaves and wood, and on leaf injury. | air pollutants are known to cause visible leaf injury as well as impairment of photosynthetic co(2) fixation. here we evaluate whether the effects on photosynthesis are large enough to cause changes in the relative composition of stable carbon isotopes, delta(13)c, of plant tissue samples, and, if so, how the changes relate to visual leaf injury. for that purpose, several woody and herbaceous plant species were exposed to so(2) + o(3) and so(2) + o(3) + no(2) for one month (8 hours per day, 5 da ... | 1988 | 16666270 |
| temporary disturbance of translocation of assimilates in douglas firs caused by low levels of ozone and sulfur dioxide. | douglas firs (pseudotsuga menziesii [mirb.] franco) are suffering strongly from air pollution in western europe. we studied the effect of low concentrations of ozone (200 micrograms per cubic meter during 3 days) and sulfur dioxide (53 micrograms per cubic meter during 28 days) on translocation of assimilates in 2 year old douglas firs. the trees were exposed to the pollutants and afterward transferred to a growth chamber adapted to the use of (14)co(2). root/soil respiration was measured daily. ... | 1988 | 16666348 |
| root growth in sitka spruce and douglas-fir transplants: dependence on the shoot and stored carbohydrates. | when dormant sitka spruce (picea sitchensis (bong.) carr.) transplants were lifted from the nursery in march and transferred to favorable growing conditions in a controlled environment chamber, new roots emerged and elongated even when the plants were bark-ringed so that the roots could not receive metabolites from the shoot by phloem translocation. carbohydrate analysis showed that starch reserves in the roots of the bark-ringed plants were depleted, indicating that these reserves provided the ... | 1988 | 14972820 |
| seasonal changes in levels of cytokinin-like compounds from douglas-fir xylem extrudate. | high-performance liquid chromatography, immunochromatography, and radioimmunoassay were used to identify cytokinin-like bases and glycosides in xylem sap of douglas-fir (pseudotsuga menziesii (mirb.) franco). isopentenyladenosine-type (isopentenyladenine and isopentenyladenosine) and zeatin-riboside type (zeatin, zeatin riboside, and dihydrozeatin riboside) cytokinins were detected during springtime. a glucosyl conjugate of zeatin riboside was also present in small amounts. levels of cytokinin-l ... | 1988 | 14972830 |
| the influence of glutamine on growth and viability of cell suspension cultures of douglas-fir after exposure to polyethylene glycol. | the response of cell cultures of douglas-fir (pseudotsuga menziesii (mirb.) franco) to osmotic stress was studied by measuring cell growth and viability after exposure to polyethylene glycol (peg) (m(r) 6000-8000). growth of cells inoculated in a medium containing 10% peg was slightly inhibited, whereas growth in a medium containing 15% peg was severely inhibited. cells grown for 6 days in nutrient medium and then subcultured in a medium containing 15% peg to induce water stress showed high viab ... | 1988 | 14972807 |
| cardiopulmonary responses after spontaneous inhalation of douglas fir smoke in goats. | in the majority of clinical cases, smoke inhalation results in a self-limited lung injury mostly confined to the airways. in this study, an animal model of inhalation injury was developed that reflected similar pathophysiology. cardiopulmonary parameters were studied in awake, instrumented goats following spontaneous inhalation of characterized douglas fir smoke. peak carboxyhemoglobin levels averaged 37% during a mean exposure time of 33 minutes. all animals survived the 24-hour study period, a ... | 1988 | 3346914 |
| an investigation of the toxic effects of combustion products--analysis of smoke components. | a comprehensive experimental design was developed to study the effects of thermal degradation products formed by the combustion of building materials on the behavior of rats. three materials were studied. they were douglas fir, wool, and polyvinyl chloride. each material was tested under both flaming and nonflaming modes of combustion. the smoke and gases produced by each material were analyzed by specific gas detector tubes, gas chromatography/mass spectrometry, and infrared spectroscopy. produ ... | 1988 | 3226125 |
| chloroplast genomes of two conifers lack a large inverted repeat and are extensively rearranged. | chloroplast genomes of douglas-fir [pseudotsuga menziesii (mirb.) franco] and radiata (monterey) pine [pinus radiata d. don], two conifers from the widespread pinaceae, were mapped and their genomes were compared to other land plants. douglas-fir and radiata pine lack the large (20-25 kilobases) inverted repeat that characterizes most land plants. to our knowledge, this is only the second recorded loss of this ancient and highly conserved inverted repeat among all lineages of land plants thus fa ... | 1988 | 2836862 |
| a two-dimensional electrophoresis procedure for single meristems of different forest species. | high resolution two-dimensional electrophoresis, with isoelectric focusing in the first dimension and electrophoresis in sodium dodecyl sulfate in thin acrylamide gels in the second dimension, has been applied to separate the proteins of single meristems (200-300 microns) from sequoiadendron giganteum, sequoia sempervirens, pseudotsuga menziesii, picea abies, pinus pinaster, eucalyptus gunnii and populus nigra. the technique may prove an efficient tool for studying inter- and intraclonal differe ... | 1989 | 2776736 |
| dispersed repetitive sequences in the chloroplast genome of douglas-fir. | restriction mapping and dna sequencing were used to characterize dispersed repetitive dna in the chloroplast genome of douglas-fir [pseudotsuga menziesii (mirb.) franco]. to map repeat families, chloroplast dna (cpdna) clones were hybridized at high stringency to one another and to cpdna cut with restriction enzymes. repeats are clustered in four regions of the genome and comprise at least six families. sequence analysis of one repeat family shared among three xbai fragments indicated the presen ... | 1989 | 2598277 |
| relationships among cold hardiness, root growth potential and bud dormancy in three conifers. | greenhouse-cultured, container-grown ponderosa pine (pinus ponderosa var. scopulorum engelm.), interior douglas-fir (pseudotsuga menziesii var. glauca (beissn.) franco) and engelmann spruce (picea engelmannii (parry) engelm.) were cold acclimated and deacclimated in growth chambers over 19 weeks. stem cold hardiness, total new root length at 14 days and days to bud break were measured weekly. relationships among cold hardiness, root growth potential (rgp) and bud dormancy suggest that cold hardi ... | 1989 | 14972975 |
| evidence of cytokinin bases, ribosides and glucosides in roots of douglas-fir, pseudotsuga menziesii. | concentrations of cytokinin-like compounds were measured in root tips of douglas-fir (pseudotsuga menziesii (mirb.) franco) collected in spring. cytokinin bases and ribosides were estimated by radioimmunoassay after purification by immunoaffinity (zeatin riboside and isopentenyladenosine antibodies coupled to cellulose gel) and high performance liquid chromatography. cytokinin glucosides were similarly analyzed in root extracts treated with beta-glucosidase and octadecyl-silica column chromatogr ... | 1989 | 14972999 |
| the contribution of ammonia emissions from agriculture to the deposition of acidifying and eutrophying compounds onto forests. | in the vicinity of a large ammonia emission area, dry and wet deposition of acidifying and eutrophying compounds onto douglas fir forests was studied by sampling throughfall, stemflow and bulk precipitation. deposition amounts of nh(4)(+) and so(4)(2-) were recognised to be among the highest of central europe, resulting in extremely high inputs of (potential) acid to the forest soils (13.1 keq ha(-1) year(-1)). the contribution of nh(3) emissions from agriculture to the total acid deposition to ... | 1989 | 15092390 |
| distribution of endogenous indole-3-acetic acid and compression wood formation in reoriented branches of douglas-fir. | five-year-old segments of intact 7-year-old branches of douglas-fir (pseudotsuga meziesii [mirb.] franco) were reoriented to determine the relation between indole-3-acetic acid (iaa) and the formation of compression wood. eight branches per treatment were either left at their original angle (mean of 69 degrees , the control), or bent proximal to the segment to reorient it up or down 30 degrees . differentiating xylem tissue from the upper and lower sides of each segment was collected and extract ... | 1989 | 16667021 |
| cytokinins in vegetative and reproductive buds of pseudotsuga menziesii. | immunoaffinity techniques using columns of immobilized antibodies raised against zeatin riboside and isopentenyladenosine were found to be effective in isolating cytoklnins from vegetative, female, and male buds of douglas-fir (pseudotsuga menziesii [mirb.] franco). the purified cytokinins were separated by reverse phase high performance liquid chromatography and analyzed by radioimmunoassay. confirmation of cytokinin identities was by gas chromatography-mass spectrometry. immediately prior to b ... | 1990 | 16667467 |
| extended host range of agrobacterium tumefaciens in the genus pinus. | two-to 4-month-old seedlings of nine pine species (pinus eldarica medw., pinus elliottii engelm., pinus jeffreyi grev. & balf., pinus lambertiana dougl., pinus ponderosa laws., pinus radiata d. don, pinus sylvestris l., pinus taeda l., pinus virginiana mill), douglas fir (pseudotsuaa menziesii (mirb.) franco) and incense cedar (libocedrus decurrens torr.) were inoculated with five strains of agrobacterium tumefaciens. transformation occurred in all conifer species tested as determined by gall fo ... | 1990 | 16667394 |
| expression of cab genes in douglas-fir is not strongly regulated by light. | dark-grown douglas-fir (pseudotsuga menziesii [mirb.] franco) seedlings had approximately 30% of the major polypeptide of the light-harvesting chlorophyll a/b binding protein, 30% of cab mrna, 54% of psba mrna, and 14% of total chlorophyll, in comparison with amounts in light-grown seedlings. seedlings entrained under a 24-hour photoperiod of light and dark showed small diurnal fluctuations in cab and psba mrna levels and, when transferred to continuous conditions, no circadian rhythms in mrna l ... | 1990 | 16667545 |
| the population biology of bromus tectorum in forests: effect of disturbance, grazing, and litter on seedling establishment and reproduction. | the effect of tree canopy, understory, herbivores, and litter depth on seedling establishment, survival, and reproduction of the alien grass, bromus tectorum (cheatgrass), was examined in a series of experiments in four forest habitat types in western north america. higher recruitment, survival, and reproduction on clearcuts, which would be expected if the overstory alone is limiting the distribution of cheatgrass in forests, were not observed. removing the understory in an otherwise undisturbed ... | 1990 | 28312970 |
| the population biology of bromus tectorum in forests: distinguishing the opportunity for dispersal from environmental restriction. | with increasing elevation and corresponding changes in the macroclimate, forest zones in the intermountain region of western north america are often dominated in turn by pinus ponderosa, pseudotsuga menziesii, abies grandis, an thuja plicata. bromus tectorum (cheatgrass), and introduced annual grass now abundant in the region's steppe, is uncommon in mature stands representative of these forest zones. in order to determine whether b. tectorum is largely excluded from these forests by insufficien ... | 1990 | 28312969 |
| selection and physiology of cell cultures of douglas-fir grown under conditions of water stress. | douglas-fir (pseudotsuga menziesii (mirb.) franco) cell cultures sampled 3, 6, or 9 days after subculture in nutrient medium were able to survive subsequent subculture in a medium containing 15% polyethylene glycol (peg) (m(r) 6000-8000) (-1.21 mpa), whereas cell sampled 12 or 16 days after subculture in nutrient medium became senescent when transferred to a medium containing 15% peg. cells sampled after subculture for 3, 6, or 9 days in nutrient medium had lower fresh weight/dry weight ratios, ... | 1990 | 14972942 |
| comparison of three cold hardiness tests for conifer seedlings. | greenhouse-cultured, container-grown ponderosa pine (pinus ponderosa var. scopulorum engelm.), interior douglas-fir (pseudotsuga menziesii var. glauca (beissn.) franco), and engelmann spruce (picea engelmannii (parry) engelm.) were cold acclimated and deacclimated in growth chambers over 19 weeks. cold hardiness was measured weekly by a whole-plant freeze test and by two quick tissue tests: freeze-induced electrolyte leakage of needles, and differential thermal analysis of buds. the whole-plant ... | 1990 | 14972928 |
| effects of aluminum on growth and nutrient status of douglas-fir seedlings grown in culture solution. | effects of al on growth, nutrient uptake and proton efflux were studied in douglas-fir (pseudotsuga menziesii (mirb.) franco) seedlings grown for about nine months in culture solutions with a ph between 3.4 and 3.6 and with both calcium and magnesium (ca + mg) at a concentration of 0.1, 0.5 or 2.5 mm. in the absence of al, plant dry matter production and root development increased with increasing concentrations of (ca + mg) in the culture solution. at the low and intermediate (ca + mg) concentra ... | 1990 | 14972948 |
| lignified materials as potential medicinal resources. ii. prevention of pathogenic bacterial infections in mice. | antibacterial activity was demonstrated when ddy mice were intraperitoneally infected with e. coli or p. aeruginosa two days after a single ip-injection of a hot-water or alkaline extract obtained from lignified materials, such as chips of slash pine, douglas fir, tallow wood, and two shelf fungi. lignified material is a promising medicinal resource for the prevention and/or treatment of pathogenic microbial infection. | 1990 | 2103363 |
| sequence of the gene for the large subunit of ribulose 1,5-bisphosphate carboxylase from a gymnosperm, douglas fir. | 1990 | 2103468 | |
| identification of an agrobacterium tumefaciens virulence gene inducer from the pinaceous gymnosperm pseudotsuga menziesii. | inducible t-strand mobilization from the ti plasmid of agrobacterium tumefaciens to the genome of a plant host is mediated by the activation of a cascade of bacterial virulence genes. it is initiated when the bacterium senses the presence of a low molecular weight inducer secreted by the plant. although many hydroxyphenylpropanoid and phenolic compounds can activate the virulence cascade, the only native inducers that have been identified to date are acetosyringone and hydroxyacetosyringone. a n ... | 1990 | 2110367 |
| contemporary use of bark for medicine by two salishan native elders of southeast vancouver island, canada. | elders of the saanich and cowichan coast salish people of southern vancouver island treat, or have treated in the recent past, many ailments with bark preparations. interviews with two elder salishan women revealed that: respiratory ailments were treated with bark of abies grandis, arbutus menziesii, cornus nuttallii, prunus emarginata, pseudotsuga menziesii and quercus garryana; digestive tract ailments with the bark of abies grandis, alnus rubra, arbutus menziesii, malus fusca. oemleria cerasi ... | 1990 | 2345461 |
| lignified materials as potential medicinal resources. iii. diversity of biological activity and possible molecular species involved. | diverse biological activities of hot-water and alkali extracts of lignified materials were reviewed and the molecular species involved are discussed. materials tested included pine cone of pinus parviflora sieb. et zucc., wood chips of slash pine, douglas fir, and tallow wood, and two basidiocarps, in addition to their partially degraded preparations and commercial lignins. as a tentative conclusion, the lignin structure of these extracts might be responsible for the potent stimulation of granul ... | 1990 | 2085883 |
| decreased biocide susceptibility of adherent legionella pneumophila. | in a study of the in vitro effectiveness of biocides against legionella pneumophila, some aspects of the cooling tower environment were replicated in the laboratory, paying particular attention to water hardness and ph. pieces of douglas fir and polyvinyl chloride were colonized in a recirculating system and the comparative efficacy of two biocides (bronopol and kathon) against the sessile and planktonic populations was examined. while the biocides were relatively effective against the planktoni ... | 1991 | 1778846 |
| tracheal obstruction caused by tree needles in a cat. | tracheal obstruction was suspected in a 1-year-old female domestic shorthair cat. clinical signs consisted of inspiratory and expiratory dyspnea and cyanosis. the cat did not improve when treated with oxygen, epinephrine, prednisolone sodium succinate, and aminophylline. bronchoscopy revealed obstruction of the trachea and carina by a 2.5-cm twig and needles from a douglas fir tree. needles had migrated into distal airways. the cat was euthanatized at the owner's request. | 1991 | 1917661 |
| carbon budgets of temperate forest ecosystems. | a summary of carbon-budget data from 30 forest stands is presented together with information on both above- and belowground ecosystem components. only 10 of the stands had complete biomass data, 21 had complete productivity data and six had heterotrophic, or autotrophic respiration data, or both. the most comprehensive stand-level data have been collected for pinus spp., pseudotsuga menziesii, abies amabilis and liriodendron tulipifera. only incomplete carbon budgets are available for most ecosy ... | 1991 | 14972857 |
| new root growth of douglas-fir seedlings at low carbon dioxide concentration. | new root growth of conifer nursery seedlings is dependent on light, but whether this is necessary only for photosynthesis, or also has some other root growth promoting effect is unknown. this question was investigated using one-year-old douglas-fir (pseudotsuga menziesii (mirb.) franco) seedlings grown at two nurseries from the same seed lot and taken from cold storage in march and april. new root production was examined in two 10-day root growth capacity (rgc) experiments. seedlings were subjec ... | 1991 | 14972879 |
| chloroplast dna restriction fragment length polymorphism in sequoia sempervirens d. don endl., pseudotsuga menziesii (mirb.) franco, calocedrus decurrens (torr.), and pinus taeda l. | the extent and type of chloroplast dna restriction fragment length polymorphism was determined among individual tree samples of coast redwood, douglas fir, incense-cedar, and loblolly pine. a total of 107 trees was surveyed for three restriction enzymes (bamhi, ecori, hindiii) and six chloroplast dna probes from petunia (p3, p4, p6, p8, p10, s8). the probes comprise 64% of the petunia chloroplast genome. polymorphisms were detected in all species but loblolly pine. coast redwood and incense-ceda ... | 1991 | 24221163 |
| transient gene expression of microprojectile-introduced dna in douglas-fir cotyledons. | plasmid dna containing the reporter gene uida encoding β-glucuronidase (gus), driven by the cauliflower mosaic virus 35s promoter, was introduced on high-velocity microprojectiles into cultured cotyledons of douglas-fir [pseudotsuga menziesii (mirb.) franco]. transient gene expression was measured by counting the number of distinct loci of gus activity per cotyledon. contrary to published results on angiosperms, repeated bombardments did not increase expression in douglas-fir. expression varied ... | 1991 | 24221286 |
| defense mechanisms of conifers : relationship of monoterpene cyclase activity to anatomical specialization and oleoresin monoterpene content. | cell-free extracts from pinus ponderosa lawson (ponderosa pine) and pinus sylvestris l. (scotch pine) wood exhibited high levels of monoterpene synthase (cyclase) activity, whereas bark extracts of these species contained no detectable activity, and they inhibited cyclase activity when added to extracts from wood, unless polyvinylpyrrolidone was included in the preparation. the molecular mass of the polyvinylpyrrolidone added was of little consequence; however, polyvinylpolypyrrolidone (a cross- ... | 1991 | 16668182 |
| technique for using microencapsulated terpenes in lepidopteran artificial diets. | we have developed and tested a technique to microencapsulate terpene compounds by forming gelatin-walled microcapsules around the terpene essential oils. eight terpenes that are common constituents of douglas fir (pseudotsuga menziesii) oleoresin were encapsulated, including five monoterpenes (α-pinene,β-pinene, camphene, myrcene, and limonene) and three oxygenated monoterpenes (bornyl acetate, linalool, andβ-citronellol). the encapsulated terpenes were mixed into artificial diets to determine t ... | 1992 | 24253865 |
| absolute and relative growth of douglas-fir seedlings of different sizes. | douglas-fir (pseudotsuga menziesii (mirb.) franco) seedlings of a single seed source were grown in a bare-root nursery for two years to produce five different stock types by varying spacing and transplanting treatments. they were then planted in the forest together with one-year-old container seedlings of the same seed source, which constituted a sixth treatment. stem volume mean relative growth rate (r(v)) was low immediately after planting for all stock types except the container seedlings, an ... | 1992 | 14969865 |
| root growth and water use efficiency of douglas-fir (pseudotsuga menziesii (mirb.) franco) and lodgepole pine (pinus contorta dougl.) seedlings. | one-year-old douglas-fir (pseudotsuga menziesii (mirb.) franco) and lodgepole pine (pinus contorta dougl.) seedlings were grown for 17 weeks in 100-cm deep, 7.8-liter containers. two douglas-fir provenances, one from a wet and one from a dry site in coastal british columbia, and two lodgepole pine provenances, one from a wet and one from a dry site in interior british columbia, were grown in wet (522% water content) or dry (318% water content) peat/vermiculite soil in a factorial design. each co ... | 1992 | 14969945 |
| evaluation of methods for detecting ecological effects from genetically engineered microorganisms and microbial pest control agents in terrestrial systems. | this report summarizes and evaluates research from several laboratories that deals with the detection of ecological effects induced through exposure of microbes or plants to genetically engineered microorganisms (gems) and microbial pest control agents (mpcas). some 27 potential endpoints for measuring effects have been studied. perturbations induced by gems have been detected in about one-half of these endpoints. detectable effects have been recorded for over half of the 16 species of bacteria ... | 1992 | 14544532 |
| ex vitro photosynthetic activity in plantlets of tissue-cultured douglas-fir. | plantlets of douglas-fir (pseudotsuga menziesii (mirb.) franco) had lower rates of net co(2) uptake and higher rates of root respiration than greenhouse-grown seedlings. they also had a lower photosynthetic efficiency at high photosynthetic photon flux density, and exhibited significant depression of co(2) uptake under water stress. the ability of plantlets to utilize high irradiance and to photosynthesize under conditions of water stress was enhanced by the presence of many roots. carbon dioxid ... | 1992 | 14969977 |
| physiology and morphology of douglas-fir rooted cuttings compared to seedlings and transplants. | cuttings of douglas-fir (pseudotsuga menziesii (mirb.) franco) from three open-pollinated families were rooted in two types of tray, and then grown for 1.5 years in a bareroot nursery. during their second winter they were sampled periodically and tested for cold hardiness, dormancy status, root growth potential and various morphological characteristics. two-year-old seedlings and transplants were tested concurrently for comparison. rooted cuttings, seedlings and transplants cold hardened at simi ... | 1992 | 14969868 |
| effects of atmospheric ammonia and ammonium sulphate on douglas fir (pseudotsuga menziesii). | three-year-old douglas firs (pseudotsuga menziesii) were fumigated with 180 microg m(-3) nh3 or clean (charcoal-filtered) air. during these fumigations the plants received 15 mm artificial rain weekly, supplemented with 20, 500 or 2500 micromol litre(-1) (nh4)2so4. exposure to nh3 and nh4+ for 14 weeks resulted in a change of the nutrient status of the needles. the most remarkable effect was the increase in the n/k ratio, due to both uptake of n and leaching of k. the action of nh3 was stronger ... | 1992 | 15092001 |
| nutrient leaching from conifer needles in relation to foliar apoplast cation exchange capacity. | limited evidence to date suggests that acidic precipitation promotes leaching of nutrient cations from conifer foliage. in order to evaluate the relative contribution of the apoplast cation exchange complex and symplast nutrient pools to the leached ions, the magnitude of foliar leaching in response to acidic solutions was compared to foliar apoplast cation exchange capacity (cec) for two conifer tree species (pseudotsuga menziesii and picea engelmanii). leaching potential was determined by imme ... | 1992 | 15092012 |
| research on the impact of forest stand structure on atmospheric deposition. | dry and wet deposition onto thirty forest stands in relation to stand structure is studied by sampling throughfall and bulk precipitation. nine measurement sites are situated in pseudotsuga menziesii stands, ten in pinus sylvestris and eleven in quercus robur stands. all stands are situated within a radius of 1.2 km to assure a more or less equal air pollution load. in each stand, detailed forest structure inventories are made to determine aerodynamic roughness, collecting efficiency and surface ... | 1992 | 15092040 |
| measurement of dry deposition of ammonia on a forest. | ammonia concentration gradients above a douglas fir canopy were measured from 16 august to 31 december 1989 by two automated high-precision thermodenuders at the location speulderbos in the netherlands. concentration gradients were used to calculate the dry deposition flux of ammonia via flux-gradient theory. meteorological data were obtained from a nearby tower. ammonia concentrations were highly variable with highest values during the night. concentration gradients were very small during dayti ... | 1992 | 15092045 |
| a repetitive proline-rich protein from the gymnosperm douglas fir is a hydroxyproline-rich glycoprotein. | intact cell elution of suspension cultures derived from douglas fir, pseudotsuga menziesii (mirbel) franco, yielded two extensin monomers, the first hydroxyproline-rich glycoproteins (hrgps) to be isolated from a gymnosperm. these hrgps resolved on superose-6 gel filtration. the smaller monomer was compositionally similar to angiosperm extensins like tomato p1. the larger monomer had a simple composition reminiscent of repetitive proline-rich proteins (rprps) from soybean cell walls and containe ... | 1992 | 16668765 |
| a gymnosperm extensin contains the serine-tetrahydroxyproline motif. | the extensin family is a diverse group of hydroxyproline-rich glycoproteins located in the cell wall and characterized by repetitive peptide motifs glycosylated to various degrees. the origin of this diversity and its relationship to function led us earlier to compare extensins of the two major groups of angiosperms from which we concluded that the highly glycosylated ser-hyp(4) motif was characteristic of advanced herbaceous dicots, occurring rarely or not at all in a representative graminaceou ... | 1992 | 16668921 |
| cloning and sequencing of an agrobacterium tumefaciens beta-glucosidase gene involved in modifying a vir-inducing plant signal molecule. | induction of agrobacterium tumefaciens virulence genes by plant phenolic compounds is essential for successful t-dna transfer to a host plant. in douglas fir needles, the major virulence region inducer is the glycoside coniferin (j. w. morris and r. o. morris, proc. natl. acad. sci. usa 87:3612-3618, 1990). agrobacterium strains with high beta-glucosidase activity respond to coniferin and infect douglas fir seedlings, whereas most strains with low beta-glucosidase activity fail to respond to con ... | 1992 | 1537792 |
| biosynthesis of monoterpenes: regio- and stereochemistry of (+)-3-carene biosynthesis. | incubation of [1-3h1]geraniol with stem disks of douglas fir (pseudotsuga menziesii) and incubation of [1-3h1]geranyl pyrophosphate with both a soluble enzyme extract from douglas fir and a partially purified preparation of (+)-3-carene synthase from lodgepole pine (pinus contorta) resulted in the production of (+)-3-[3h] carene. subsequent conversion of the product to car-3-en-5-one and to 4-isocaranone followed by base-catalyzed exchange of the alpha-hydrogens established that the 3h located a ... | 1993 | 8373196 |
| molecular cloning and characterization of a legumin-like storage protein cdna of douglas fir seeds. | a cdna library was made from poly(a)+ rna isolated from developing douglas fir (pseudotsuga menziesii) embryo and megagametophytic tissue, and the cdna clones were identified by immunoscreening with polyclonal antiserum against the crystalloid storage protein complex of douglas fir. the nucleotide sequence of the longest cdna insert (df1) was analysed. the amino acid sequence derived from the dna sequence verified its identity as a legumin-like storage protein (pseudotsugin) and confirmed that t ... | 1993 | 8448370 |
| chloroplast dna diversity among trees, populations and species in the california closed-cone pines (pinus radiata, pinus muricata and pinus attenuata). | the amount, distribution and mutational nature of chloroplast dna polymorphisms were studied via analysis of restriction fragment length polymorphisms in three closely related species of conifers, the california closed-cone pines-knobcone pine: pinus attenuata lemm.; bishop pine: pinus muricata d. don; and monterey pine: pinus radiata d. don. genomic dna from 384 trees representing 19 populations were digested with 9-20 restriction enzymes and probed with cloned cpdna fragments from douglas-fir ... | 1993 | 7905846 |
| three dimensional distribution of needle and stem surface area in a douglas-fir. | the distribution of needles and branches in the crown of a 14-m tall douglas-fir was investigated for the purpose of developing a three-dimensional structure for use with radiation transfer models. we found a linear relationship between the basal area of main branches originating at the bole and the total one-sided planimetric surface area of the foliage attached to each branch. a similar linear relationship was found between the branch basal area and the mass of stem material on the branch. tot ... | 1993 | 14969896 |
| effects of foliar nitrogen concentration on photosynthesis and water use efficiency in douglas-fir. | leaf-level physiological processes were studied in douglas-fir (pseudotsuga menziesii (mirb.) franco) to determine whether apparent increases in stand-level water use efficiency (wue) observed in response to nitrogen (n) fertilization were attributable to foliar n effects on carbon fixation rates or on stomatal control of water loss. photosynthesis and transpiration were measured at different light intensities and ambient co(2) molar fractions and comparisons were made between current-year shoot ... | 1993 | 14969910 |
| the effects of atmospheric nitrogen deposition and soil chemistry on the nutritional status of pseudotsuga menziesii, pinus nigra and pinus sylvestris. | the ammonium content and the base cation content, expressed relative to ammonium, are enhanced in the soil of dutch forests, due to the extremely high deposition of ammonium to the forest floor. a nation-wide investigation was carried out to establish whether and how these changed nitrogen fluxes in deposition and soil affect the nutritional status of coniferous trees. the chemical composition of needles of douglas fir, scots pine and corsican pine showed a regional trend similar to that of depo ... | 1993 | 15091876 |
| frost injury prediction model for douglas-fir seedlings in the pacific northwest. | because simple seed- or breeding-zone guidelines are inadequate for controlling the risk of maladaptation to environmental stresses, we are developing operational procedures to assess the risk of frost kill to genetically improved families of douglas-fir (pseudotsuga menziesii mirb. franco). we have (1) determined the time course of cold hardening and dehardening of nursery-grown douglas-fir seedlings over four winters, by means of controlled freezing tests, (2) fitted curves to relationships be ... | 1994 | 14967654 |
| seasonal biochemical changes in coniferous forest canopies and their response to fertilization. | seasonal changes in concentrations of total nitrogen, free amino acids, chlorophyll, starch and sugar were measured in foliage from fertilized and unfertilized conifer forests in new mexico and oregon. in the new mexico douglas-fir (pseudotsuga menziesii var glauca (beissn.) franco) forest, fertilization resulted in elevated foliar nitrogen concentrations on all dates, from an average of 9 mg g(-1) in unfertilized trees to 14 mg g(-1) in fertilized trees. in the oregon western hemlock (tsuga het ... | 1994 | 14967674 |
| maturation in douglas-fir: i. changes in stem, branch and foliage characteristics associated with ontogenetic aging. | two experiments were conducted to characterize changes associated with ontogenetic aging in coastal douglas-fir (pseudotsuga menziesii (mirb.) franco) and to identify possible maturation "markers" for this species. in the first experiment (experiment 1), scions of ages 1, 4 and 9 years were collected from four seed zones in field progeny tests and grafted onto 1-year-old rootstocks. in experiment 2, scions from five full-sib families of ages 1 and 10 years were collected from one progeny test an ... | 1994 | 14967615 |
| maturation in douglas-fir: ii. maturation characteristics of genetically matched douglas-fir seedlings, rooted cuttings and tissue culture plantlets during and after 5 years of field growth. | seedlings, rooted cuttings from juvenile stock plants, and cotyledon-derived tissue culture plantlets were propagated from several coastal douglas-fir (pseudotsuga menziesii (mirb.) franco) full-sib families so that the rooted cuttings and plantlets were clonally identical. the stock types (seedlings, rooted cuttings and plantlets) were planted in the field in spring 1987. in fall 1991, after five complete growing seasons, the plants were measured and these values compared to maturation "markers ... | 1994 | 14967616 |
| adaptive significance of intermittent shoot growth in douglas-fir seedlings. | we tested the hypothesis that intermittent (lammas) shoot growth in douglas-fir (pseudotsuga menziesii var menziesii (mirb.) franco) seedlings from dry regions of southwest oregon is adaptively significant. seedlings from open-pollinated families (160 total) from two inland (dry) and two coastal (wet) sources were grown under either well-watered or intermittent drought conditions (temporary drought followed by rewatering) for two growing seasons. in the first growing season, the results supporte ... | 1994 | 14967617 |
| effects of short-term ozone exposure and soil water availability on the carbon economy of juvenile douglas-fir. | effects of ozone and soil water availability on partitioning and translocation of assimilates were studied in three-year-old douglas-fir (pseudotsuga menziesii [mirb.] franco) seedlings exposed, in separate experiments, to 0 and 106 or 0 and 514 micro g m(-3) ozone for 8 h day(-1) for 9 days. the dynamics of carbon from assimilated (14)co(2) were followed. no interactions between ozone and soil water content were observed. total net uptake of carbon was reduced by low soil water content, but was ... | 1994 | 14967680 |
| smoke inhalation with a concurrent systemic stress results in lung alveolar injury. | smoke inhalation causes injuries to lung airways, and, at times, alveolar inflammation also develops over approximately 24 h. the pathophysiology of parenchymal lung injuries is unknown, and it is often fatal. we hypothesized that an inflammatory stress remote from the smoke-related lung insult was required for development of alveolar injuries. spontaneously breathing rats were exposed, head only, to smoke generated by nonflaming pyrolysis (smoldering) of douglas fir wood (df), polyvinylchloride ... | 1994 | 8111586 |
| comparison of the inhibitory effects of monomeric, dimeric, and trimeric procyanidins on the biochemical markers of skin tumor promotion in mouse epidermis in vivo. | several procyanidin dimers and an epicatechin trimer purified from douglas fir bark tannins were compared with their monomer components (+)-catechin and (-)-epicatechin for their abilities to inhibit the biochemical effects of the potent tumor promoter 12-o-tetradecanoylphorbol 13-acetate (tpa) in mouse epidermis in vivo. topical applications of the procyanidins, 15 min before the tumor promoter, inhibit tpa-induced ornithine decarboxylase (odc) activity and this inhibition increases with the de ... | 1994 | 8073090 |
| role of neutrophils and nitric oxide in lung alveolar injury from smoke inhalation. | we examined potential mechanisms responsible for the parenchymal lung injury seen in an animal model of smoke inhalation with concurrent inflammation. rats injected with sterile glycogen and exposed to smoke generated by the nonflaming pyrolysis of combined douglas fir wood and polyvinylchloride showed a 74% increase in 125i-albumin lung permeability and a fivefold increase in lung myeloperoxidase (mpo) compared with control rats. there was also a significant increase in plasma indices of oxidat ... | 1994 | 8049812 |
| inhibition of eukaryote signal-regulated protein kinases by plant-derived catechin-related compounds. | the cladodes of phyllocladus trichomanoides, the bark of pseudotsuga menziesii and the heartwood of acacia melanoxylon contain catechin derivatives that are potent inhibitors of rat brain protein kinase c. most of these compounds are also inhibitors of bovine heart cyclic amp-dependent protein kinase catalytic subunit and wheat ca(2+)-dependent protein kinase. however, these compounds are either not inhibitors or are relatively poor inhibitors of avian myosin light chain kinase. the most potent ... | 1994 | 7515625 |
| molecular cloning and characterization of a legumin-like storage protein cdna of douglas fir seeds. | 1994 | 7999993 | |
| role of douglas fir (pseudotsuga menziesii) carbohydrates in resistance to budworm (choristoneura occidentalis). | the current year's growth of douglas fir contains galactose, unusual in that this carbohydrate makes up 78.7% of the total carbohydrate fraction. an agar diet study was undertaken to determine the effects of galactose, other carbohydrates, and terpenes on western spruce budworm larval mortality, growth rate, and adult biomas production. all concentrations of the carbohydrates and terpenes tested, as well as other mineral elements not tested, were typical of the current year's foliage of douglas ... | 1994 | 24242063 |
| mapped dna probes from loblolly pine can be used for restriction fragment length polymorphism mapping in other conifers. | a high-density genetic map based on restriction fragment length polymorphisms (rflps) is being constructed for loblolly pine (pinus taeda l.). consequently, a large number of dna probes from loblolly pine are potentially available for use in other species. we have used some of these dna probes to detect rflps in 12 conifers and an angiosperm. thirty complementary dna and two genomic dna probes from loblolly pine were hybridized to southern blots containing dna from five species of pinus (p. elli ... | 1994 | 24186006 |
| tandem mass spectrometry and structural elucidation of glycopeptides from a hydroxyproline-rich plant cell wall glycoprotein indicate that contiguous hydroxyproline residues are the major sites of hydroxyproline o-arabinosylation. | hydroxyproline-rich glycoproteins (hrgps) occur in the extracellular matrix of land plants and green algae. hrgps contain from 2 to 95% of their dry weight as carbohydrate, predominantly as oligoarabinosides and/or as heteropolysaccharides which are o-linked to the hydroxyproline residues. a glycosylation code that determines the presence or absence and extent of arabinosylation at each hydroxyproline residue is likely, as each hrgp has a unique arabinosylation profile. previously we noted a pos ... | 1995 | 7852316 |
| a mutation hotspot in the chloroplast genome of a conifer (douglas-fir: pseudotsuga) is caused by variability in the number of direct repeats derived from a partially duplicated trna gene. | we determined the dna sequence of a 2.7-kb cpdna xbai fragment from douglas-fir [pseudotsuga menziesii (mirb.) franco]. rflps revealed by the 2.7-kb xbai clone were observed to vary up to 1 kb among species within the genus pseudotsuga and up to 200 bp among trees of p. menziesii. the polymerase chain reaction (pcr) allowed the locus of polymorphism to be identified, and the variable region was then sequenced in a second douglas-fir tree, a single tree of a related species, japanese douglas-fir ... | 1995 | 7553944 |
| red oak condensate: its apparent lack of cytotoxic and genotoxic effects as compared with three other wood-drying condensates. | a major activity of the lumber industry is the kiln-drying of wood. in order to ascertain whether wood-drying condensates pose a possible environmental hazard, the cytotoxicity and genotoxicity of these condensates in vitro, were tested using an assay validated using chinese hamster ovary (cho) cells and a known genotoxicant, mitomycin c. subsequently, the assay was developed for the human peripheral blood lymphocyte (hpbl) system, as it was felt that results derived from human cells would refle ... | 1995 | 8829893 |
| mitochondrial dna products among rapd profiles are frequent and strongly differentiated between races of douglas-fir. | racial differentiation and genetic variability were studied between and within the coastal, north interior, and south interior races of douglas-fir using rapd and allozyme markers. nearly half of all rapd bands scored (13: 45%) were found to be amplified from mitochondrial dna. they exhibited maternal inheritance among hybrids and backcrosses between the races, and were much more highly differentiated (gst = 0.62 for haplotype frequencies) than were allozymes (gst = 0.26). no evidence of hybridi ... | 1995 | 8574443 |
| carbon isotope variation in douglas-fir foliage: improving the delta(13)c-climate relationship. | the natural abundance of stable carbon isotopes in the annual rings of forest trees is used as a tracer of environmental changes such as climate and atmospheric pollution. although tree-ring delta(13)c varies by about 2 per thousand from year to year, variability within the foliage can be as high as 6 per thousand. recent studies have shown that branch length affects stomatal response, which influences the integrated foliar delta(13)c signal. to improve the ability of delta(13)c to predict clima ... | 1995 | 14965999 |
| pollen management for intensive seed orchard production. | artificially increasing pollen supply (supplemental mass pollination (smp)) to conifer seed orchards has the potential to increase seed yields and improve the genetic worth of seed crops that would otherwise suffer from the detrimental effects of pollen contamination and unbalanced paternal contribution. however, success rates, measured as the proportion of seed fertilized by smp, have been low. this review examines the concepts underlying smp and presents data for two smp field trials with doug ... | 1995 | 14965935 |
| growth response of bigcone douglas fir (pseudotsuga macrocarpa) to long-term ozone exposure in southern california. | long-term radial growth of bigcone douglas fir (pseudotsuga macrocarpa) was studied throughout its range in the san bernardino mountains of southern california, where ambient ozone has been high for approximately the past 40 years. a gradient of both ozone concentration and precipitation exists from west (high) to east (low). growth rates of bigcone douglas fir are considerably lower since 1950 throughout the san bernardino mountains, with the largest growth reductions in the western part of the ... | 1995 | 15658165 |
| correlations between stable carbon-isotope abundance and hydraulic conductivity in douglas-fir across a climate gradient in oregon, usa. | stomatal conductance in trees is related to both foliar carbon-isotope abundance and stem hydraulic properties. by combining these relationships, i hypothesized that carbon-isotope abundance in foliage should vary with limitations to water movement through supporting branches. i sampled douglas-fir branches (pseudotsuga menziesii (mirb.) franco) from six sites across a climate gradient in oregon, usa for foliar carbon-isotope abundance and stem hydraulic properties. i used a forest growth model ... | 1996 | 14871681 |
| root growth potential as an indicator of drought stress history. | container-grown quiescent douglas-fir (pseudotsuga menziesii var. glauca (beissn.) franco) seedlings were air dried to plant water potentials of -0.2, -2.2 or -3.8 mpa (unstressed, moderate, and severe stress treatments, respectively). trees from each treatment were either placed in root mist chambers held at 10, 20, or 28 degrees c for 28 days and root growth potential (rgp) and plant water potential (pwp) measured weekly, or potted in a 1/1 mix of peat and vermiculite, watered only once, and h ... | 1996 | 14871687 |
| effects of formaldehyde-enriched mists on pseudotsuga menziesii (mirbel) franco and lobaria pulmonaria (l.) hoffm. | the atmosphere in some areas is polluted with formaldehyde (hcho); however, little is known about effects of hcho on plants at concentrations resembling those in polluted areas. the effects of simulated fogwater enriched with hcho on seedlings of pseudotsuga menziesii (mirbel) franco (douglas fir) and pendants of lobaria pulmonaria (l.) hoffm. were assessed. plants were treated with hcho-enriched fog (target concentrations of 100, 500, and 1000 microm) during five 4-night mist sessions. growth a ... | 1996 | 15093509 |
| geographic distribution of cytoplasmic polyhedrosis virus infection in douglas-fir tussock moth larvae, orgyia pseudotsugata, in british columbia | we have examined the geographic distribution and prevalence of insect-specific viral infections in douglas-fir tussock moth populations in british columbia. nucleic acids extracted from field collected egg masses from 10 different locations in british columbia were subjected to agarose gel electrophoresis and southern blot analysis. electrophoresis of nucleic acids after digestion with rnase a at high and low ionic strengths showed that the extra bands detected in agarose gels were double-strand ... | 1996 | 8812604 |
| post-termination-induced and hormonally dependent expression of low-molecular-weight heat shock protein genes in douglas fir. | we have isolated and sequenced two cdna clones (pm 18.2a; pm 18.2b) from douglas fir (pseudotsuga menziesii (mirb.) franco) which encode for the low-molecular-weight heat shock proteins (lmw hsps) of 18.2 kda. the predicted amino acid sequences of the two douglas fir proteins are 97.5% identical. a phylogenetic tree of class i lmw hsps showed that the pm lmw hsps are found within a subgroup consisting exclusively of dicot species indicating that class i lmw hsps evolved from a common ancestor pr ... | 1996 | 8704123 |
| structure and expression of a developmentally regulated cdna encoding a cysteine protease (pseudotzain) from douglas fir. | we report the complete sequence and expression of a cdna clone (pm3-3) encoding a cysteine protease (cysp) from pseudotsuga menziesii [mirb] (pm) franco (douglas fir). the sequence consists of a 5' untranslated region (utr) of 153-bp followed by an open reading frame (orf) of 1362 bp encoding a putative mature cysp flanked by n- and c-terminal propeptides. a 364-bp 3' utr contains multiple putative au-rich elements (are) that may be involved in the destabilization of transcripts. the deduced pri ... | 1996 | 8682307 |
| simulating secondary succession of elk forage values in a managed forest landscape, western washington | modern timber management practices often influence forage production for elk (cervus elaphus) on broad temporal and spatial scales in forested landscapes. we incorporated site-specific information on postharvesting forest succession and forage characteristics in a simulation model to evaluate past and future influences of forest management practices on forage values for elk in a commercially managed douglas fir (pseudotsuga menziesii, psme)-western hemlock (tsuga heterophylla, tshe) forest in we ... | 1996 | 8703108 |
| douglas-fir: a third wood-drying condensate found to exhibit in vitro cytotoxicity and genotoxicity. | the present study applies the approach described in mark et al. for the testing of toxic chemicals produced during the drying of douglas-fir. the genotoxic potential of douglas-fir condensate has been previously unexplored and is thus an area of appropriate concern to the forest products industry, regulatory, agencies, and the general public. previous research conducted in this laboratory has identified two wood-drying condensates that yield positive cytotoxic and genotoxic effects. the results ... | 1996 | 8726220 |
| douglas-fir root-associated microorganisms with inhibitory activity towards fungal plant pathogens and human bacterial pathogens. | a microbial culture collection composed of 1820 bacterial strains, including 298 actinomycete strains, was established from the roots of douglas-fir (pseudotsuga menziesii (mirb.) franco) seedlings harvested from conifer nurseries and forest sites. two hundred and thirty-four strains inhibited the growth of fusarium, cylindrocarpon, and (or) pythium spp. in in vitro assays. a significantly greater proportion of bacterial strains from actinomycete genera exhibited antifungal properties compared w ... | 1996 | 8764683 |
| inter- and intraspecific polymorphism at chloroplast ssr loci and the inheritance of plastids in pinus radiata d. don. | dna sequence analysis of chloroplast genomes has revealed many short nucleotide repeats analogous to nuclear microsatellites, or simple sequence repeats (ssrs). we designed pcr primers flanking five of these regions identified in the chloroplast sequence from pinus thunbergii and tested them for amplification in pinus radiata, p. elliotii, p. taeda, p. strobus, pseudotsuga menziesii, cupressus macrocarpa, four new zealand native conifer species (podocarpus totara, podocarpus hallii, podocarpus n ... | 1996 | 24162352 |
| diversity and inheritance of inter-simple sequence repeat polymorphisms in douglas-fir (pseudotsuga menziesii) and sugi (cryptomeria japonica). | we studied inter-simple sequence repeat (issr) polymorphism and inheritance in douglas-fir [pseudotsuga menziesii (mirb.) franco] and sugi (cryptomeria japonica d. don) megagametophytes using primers that anneal to simple repeats of various lengths, sequences, and non-repetitive motifs at the 5' and 3' ends. products were visualized on agarose gels with ethidium bromide staining. more than 60% of the 96 primers tested gave interpretable banding patterns in both douglas-fir and sugi, and the usef ... | 1996 | 24166114 |
| neolignan glycosides from pseudotsuga menziesii. | 1996 | 17252508 | |
| bleach boosting and direct brightening by multiple xylanase treatments during peroxide bleaching of kraft pulps. | the effects of multiple xylanase treatments were assessed during the peroxide bleaching of three pulps: douglas-fir (kraft); western hemlock (oxygen delignified kraft); and trembling aspen (kraft). the addition of a xylanase treatment stage, either before or after the peroxide bleaching stage(s), resulted in the enhanced brightening of all pulps. a higher brightness was achieved using two enzyme treatments, one before and one after the peroxide stage(s). both bleach boosting and direct brighteni ... | 1997 | 18634097 |
| characterization of nuclear polyhedrosis viruses from three subspecies of lambdina fiscellaria | the eastern hemlock looper (ehl), lambdina fiscellaria fiscellaria, the western hemlock looper (whl), l. fiscellaria lugubrosa, and the western oak looper (wol), l. fiscellaria somniaria, are closely related insects that are pests in canadian forests. we have used restriction endonuclease (ren) and southern blot analyses to characterize dna of nuclear polyhedrosis viruses (npvs) isolated from each of the three subspecies of l. fiscellaria. ren analysis of ehl-npv, whl-npv, and wol-npv dnas revea ... | 1997 | 9056463 |
| the isolation of a novel metallothionein-related cdna expressed in somatic and zygotic embryos of douglas-fir: regulation by aba, osmoticum, and metal ions. | to isolate genes which are expressed preferentially during embryogenesis, a douglas-fir embryogenesis cdna library was constructed and differentially screened with cdna probes made with mrna from developing and mature embryos, respectively. the cdna clone pm 2.1 was isolated based on its abundance in developing seeds and absence in mature seeds, and its predicted amino acid sequence was shown to have structural features characteristic of plant mt-like proteins. alignment of the pm 2.1 predicted ... | 1997 | 9207840 |
| visualization of golgi apparatus in methacrylate embedded conifer embryo tissue using the monoclonal antibody jim 84. | methacrylate embedding followed by resin removal has been used for the first time to visualize a membrane-associated antigen at the tissue level. monoclonal antibody jim 84 was used to stain the golgi apparatus of gymnosperm (conifer) embryos by light microscope immunocytochemistry. specificity of labelling was confirmed by electron microscope immunocytochemistry using lr-white resin. ga staining was evident in all stages of white spruce somatic embryo development from immature to mature. some r ... | 1997 | 9243805 |
| effects of shade and root confinement on the expression of plagiotropic growth in juvenile-origin douglas-fir rooted cuttings. | the purpose of this experiment was to determine why juvenile-origin douglas-fir (pseudotsuga menziesii (mirb.) franco) rooted cuttings, which remain plagiotropic (branchlike) when grown in containers in shaded glasshouses, become orthotropic (vertical) after they are transplanted to an outdoor environment. plagiotropic rooted cuttings (mean angle from vertical = 45-50 degrees) from three full-sib families were transplanted into an outdoor nursery and subjected to four treatments consisting of a ... | 1997 | 11540948 |
| evidence for red:far red signaling and photomorphogenic growth response in douglas-fir (pseudotsuga menziesii) seedlings. | in a greenhouse experiment, potted coastal douglas-fir (pseudotsuga menziesii (mirb.) franco) seedlings were grown in miniature "nelder" (nelder 1962) plots where growing space varied from 265 to 2555 cm(2) per plant. after thirty weeks, mean plant height, crown biomass and branch number increased significantly (p = 0.0141) with decreasing growing space (increasing plant density). differences in height growth became apparent about six weeks after sowing. furthermore, horizontally reflected radia ... | 1997 | 14759870 |
| light availability and photosynthesis of pseudotsuga menziesii seedlings grown in the open and in the forest understory. | the light environment, photosynthetic dynamics and steady-state net photosynthetic rates of lateral branch shoots of pseudotsuga menziesii var. glauca (beissn.) franco seedlings growing in the open and in the forest understory were investigated in situ. mean incident photosynthetic photon flux density (ppfd) was 702.5 micro mol m(-2) s(-1) on open-grown branches and 52.0 micro mol m(-2) s(-1) on understory-grown branches. mean daily durations of ppfd greater than 500, 200, and 50 micro mol m(-2) ... | 1997 | 14759910 |
| responses of picea, pinus and pseudotsuga roots to heterogeneous nutrient distribution in soil. | the spatial distribution of plant-available mineral nutrients in forest soils is often highly heterogeneous. to test the hypothesis that local nutrient enrichment of soil leads to increased root proliferation in the nutrient-rich soil zone, we studied the effects of nutrient enrichment on the growth and nutrient concentrations of douglas-fir (pseudotsuga menziesii (mirb.) franco), scots pine (pinus sylvestris l.) and norway spruce (picea abies (l.) karst.) roots. three-year-old seedlings were gr ... | 1997 | 14759912 |
| estimation of leaf area with an integrating sphere. | relative absorptance of intact branches measured with an integrating sphere was compared to leaf area estimated by conventional methods (volume displacement and scanning area meter) for three conifer species: picea mariana (mill.) bsp, pinus banksiana (lamb.) and pseudotsuga menziesii (mirb.) franco. a consistent relationship between relative absorptance and surface area emerged for the three species. the ability to predict leaf area from absorptance was further explored by measuring branches of ... | 1997 | 14759830 |
| xylem cavitation in roots and stems of douglas-fir and white fir. | roots of hardwoods have been shown to be more vulnerable to xylem cavitation than stems. this study examined whether this pattern is also observed in a conifer species. vulnerability to cavitation was determined from the pressure required to inject air into the vascular system of hydrated roots and stems, and reduce hydraulic conductance of the xylem. according to the air-seeding hypothesis for the cavitation mechanism, these air pressures predict the negative xylem pressure causing cavitation i ... | 1997 | 14759867 |
| cellobiose dehydrogenase, an active agent in cellulose depolymerization. | the ability of cellobiose dehydrogenase purified from phanerochaete chrysosporium to modify a douglas fir kraft pulp was assessed. although the addition of cellobiose dehydrogenase alone had little effect, supplementation with cellobiose and iron resulted in a substantial reduction in the degree of polymerization of the pulp cellulose. when the reaction was monitored over time, a progressive depolymerization of the cellulose was apparent with the concomitant production of cellobiono-1,5-lactone. ... | 1997 | 16535705 |
| location and survival of mycorrhiza helper pseudomonas fluorescens during establishment of ectomycorrhizal symbiosis between laccaria bicolor and douglas fir. | the mycorrhiza helper bacterium pseudomonas fluorescens bbc6, isolated from a laccaria bicolor sporocarp, consistently promotes l. bicolor-douglas fir (pseudotsuga menziesii) ectomycorrhizal formation, even with low doses of bacterial inoculum. in order to describe this phenomenon more accurately, we have looked at the location and survival of the introduced bacterial strain in the soil and in the rhizosphere during the establishment of mycorrhizal symbiosis in glasshouse and nursery experiments ... | 1997 | 16535478 |
| metabolic and genotypic fingerprinting of fluorescent pseudomonads associated with the douglas fir-laccaria bicolor mycorrhizosphere. | a collection of 300 isolates of fluorescent pseudomonads was established from douglas fir-laccaria bicolor mycorrhizas and mycorrhizosphere and from adjacent bulk soil. these isolates were first phenotypically characterized with the biolog method. taxonomic identification assigned 90% of the isolates to the different biovars of pseudomonas fluorescens, with inverted frequencies of biovars v and i from the bulk soil to the mycorrhizas, suggesting that the mycorrhizas exert a selective stimulation ... | 1997 | 16535600 |
| a model of dry matter partitioning in trees. | in mechanistic growth models, the description of assimilate allocation or dry matter partitioning plays a key role. although theoretical concepts of allocation exist, they include many parameters that cannot be quantified. therefore, many growth models use descriptive keys that represent the proportions of dry matter or carbohydrates assigned to each plant component. i have developed a model to describe the dynamic partitioning of dry matter in individual trees, and used it to investigate the ef ... | 1998 | 12651393 |
| biomass and nutrient allocation in douglas-fir and amabilis fir seedlings: influence of growth rate and nutrition. | allocation of biomass and nutrients to shoots and roots was followed for three years in fast and slow growing populations of douglas-fir (pseudotsuga menziesii (mirb.) franco), a fast growing pioneer species, and amabilis fir (abies amabilis dougl. ex j. forbes), a slow growing shade-tolerant species. seedlings were grown for three seasons in five nutrient treatments containing varying proportions of nitrogen and phosphorus (n:p). in both species, growth was greatest in the 250:20 n:p treatment ... | 1998 | 12651401 |