Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| organogenesis in in vitro cultures of embryonic shoots of abies balsamea (balsam fir). | embryonic shoots of 15- to 20-year-old abies balsamea (balsam fir) trees were soaked in (a) water for 15 min or 24 hr and (b) water with 1000 mg per 1 indolebutyric acid (iba), n-dimethylaminosuccinamic acid (alar-85), or 1-phenyl-3-methyl-5-pyrazolone (ppz), singly or in combination with 100 mg per 1 caffeic acid, for 15 min. after the soaking, the embryonic shoots were transferred to a nutrient medium. nonsoaked (control) embryonic shoots elongated and often formed a basal callus but never sho ... | 1977 | 856724 |
| differences in urinary chemistry profiles of moose on isle royale during winter. | during winters 1987-1988 (i) and 1988-1989 (ii), we assessed the physiological status of moose (alces alces) residing on the west and east ends of isle royale (michigan, usa) by collecting and chemically analyzing urine deposited in snow (snow-urine) from january to early march. samples were assayed for urea nitrogen (u), sodium (na), potassium (k), calcium (ca), phosphorus (p) and creatinine (c). throughout both winters, elevated urinary u:c ratios in snow-urine samples collected from east-end ... | 1991 | 1920659 |
| fenitrothion and aminocarb residues in water and balsam fir foliage following spruce budworm spraying programs in quebec, 1979 to 1982. | 2013 | 3697537 | |
| the persistence and fate of fenitrothion insecticide in a forest environment. ii. accumulation of residues in balsam fir foliage. | 2014 | 4433873 | |
| effects of volatile substances released by foliage of abies balsamea. | 1972 | 4621720 | |
| juvenile hormone: identification of an active compound from balsam fir. | a sesquiterpenoid ester with high juvenile hormone activity for pyrrhocoris apterus (l.) was isolated from balsam fir, abies balsamea (l.) miller, and identified as the methyl ester of todomatuic acid. | 1966 | 5919750 |
| dehydrojuvabione - a new compound with juvenile hormone activity from balsam fir. | 1967 | 6039536 | |
| residues of chlorpyrifos-methyl in balsam fir foliage, forest litter, soil, stream water, sediment and fish tissue after double aerial applications of reldan. | chlorpyrifos-methyl was applied twice at 70 g a.i./ha by means of a fixed-wing aircraft to a mixed coniferous forest near allardville, new brunswick. residue in balsam fir foliage was highest (1 ppm wet wt) 1 hr after spraying and rapidly declined to about 30% within 1 day, but persisted at a very low level (0.03 ppm wet wt) for 125 days. current year's foliage contained a higher level of residue than old foliage. chlorpyrifos-methyl persisted longer in forest litter than in soil. after 125 days ... | 1981 | 6175678 |
| insect-plant interactions: endocrine defences. | it is the inevitable consequence of evolution that competitive species living together in a restricted space must try to exclude each other. plants and insects are prime examples of this eternal competition, and although neither of these is in danger of extinction, their mutual defensive strategies are of compelling interest to the human race. plant defences based on the insecticidal activity of certain of their secondary chemicals are readily apparent. only through research into the fundamental ... | 1984 | 6559111 |
| environmental hazards of aluminum to plants, invertebrates, fish, and wildlife. | aluminum is extremely common throughout the world and is innocuous under circumneutral or alkaline conditions. however, in acidic environments, it can be a major limiting factor to many plants and aquatic organisms. the greatest concern for toxicity in north america occurs in areas that are affected by wet and dry acid deposition, such as eastern canada and the northeastern u.s. acid mine drainage, logging, and water treatment plant effluents containing alum can be other major sources of al. in ... | 1996 | 7494908 |
| electrophoretic analysis of coniferyl alcohol oxidase and related laccases. | gradient gel electrophoretic methods enabled a distinction to be made between coniferyl alcohol oxidase (cao) of lignifying cell walls and a pi approximately 9 pine "laccase" recently implicated in lignification (science 1993 260, 672). following treatment of a partially purified protein mixture from developing xylem of pinus strobus with 2-[n-morpholine]ethanesulfonic acid (mes) buffer, isoelectric focusing and sodium dodecyl sulphate-polyacrylamide gel electrophoresis indicated that cao had be ... | 1994 | 7859710 |
| comparison of ribosomal dna length and restriction site polymorphisms in gremmeniella and ascocalyx isolates. | the small subunit (ssu) and the internal transcribed spacer (its) of nuclear ribosomal dna genes from 27 specimens of the fungal genera gremmeniella and ascocalyx were amplified by pcr. length polymorphisms were observed in the ssu and allowed the differentiation of four groups among the isolates tested: (i) ascocalyx abietis; (ii) gremmeniella isolates from picea spp.; (iii) gremmeniella isolates from abies balsamea; and (iv) gremmeniella isolates from abies sacchalinensis, larix spp., and pinu ... | 1994 | 7912501 |
| liquid chromatographic determination of rh-5992, an ecdysone agonist, in some forestry matrixes. | a liquid chromatographic method is described for the analysis of rh-5992 (n'-t-butyl-n'-[3,5-dimethyl-benzoyl]-n- [-ethylbenzoyl]hydrazine) from various terrestrial and aquatic forestry matrixes and stream water. the processed soils, litter, oak foliage, sediment, aquatic plants, and fish were extracted with a mixture of acetone and water; balsam fir needles were extracted with acidified methanol solution; stream water was extracted with dichloromethane. aliquots of crude extracts were solvent p ... | 2008 | 8318862 |
| the demographic cost of reproduction and its consequences in balsam fir (abies balsamea). | it is an axiom of life-history theory that reproduction involves age-specific costs in terms of survival or future reproduction. the measurement of costs of reproduction in plants is difficult, and few field studies have measured these costs in terms of fitness or demographic components, thus creating a hiatus between theory and data. in this article, we describe methods for overcoming the problem, illustrated by a field study of balsam fir. we used serial correlation and a permutation test to d ... | 1999 | 10506547 |
| modern pollen-representation of some boreal species on islands in a large lake in canada. | studies of pollen source areas of closed-canopy sites are contradictory. some authors found that closed-canopy sites mainly collect local pollen while others found more distant sources. this dichotomy might stem from the use of canopies of varying degrees of closure, and from variations in the pollen productivity of the local vegetation and the background pollen rain. here, 30 islands were used to evaluate the pollen sources of closed-canopy sites. we compared pollen with the forest inventory in ... | 2000 | 10704644 |
| genetic discontinuity revealed by chloroplast microsatellites in eastern north american abies (pinaceae). | development of conservation strategies for fraser fir (abies fraseri) in the southern appalachian mountains depends in part on recognition of the extent to which fraser fir is genetically distinct from the closely related balsam (a. balsamea) and intermediate (a. balsamea var. phanerolepis) fir. these sibling species have exhibited intergrading, clinal variation in morphological, chemical, and genetic characteristics in prior research. chloroplast microsatellite markers were polymerase chain rea ... | 2000 | 10860908 |
| developmental expression and stress induction of glutathione s-transferase in the spruce budworm, choristoneura fumiferana. | developmental and stress-induced expression of choristoneura fumiferana glutathione s-transferase (cfgst) mrna and protein were examined using northern blots and western blots. high levels of cfgst mrna and protein were detected in 1st instar larvae and diapausing 2nd instar larvae. expression of cfgst gradually decreased during larval development from 3rd to 5th instar, after which the expression increased once again, reaching peak levels in 6th instar larvae. cfgst mrna and protein were undete ... | 2001 | 11033162 |
| size-specific fecundity and the influence of lifetime size variation upon effective population size in abies balsamea. | the hierarchy of plant size often present in dense populations of plants and the close correlation found between size and fecundity can result in an unequal distribution of fecundity, which reduces the ratio of effective population size/census number (ne/n). such an effect has been found previously in annuals, but no study has hitherto tested for the effect in the lifetime fecundity variation of a perennial population. we use the demographically stable size distribution to be found in natural, w ... | 2000 | 11240627 |
| photosynthesis and carbon allocation of six boreal tree species grown in understory and open conditions. | one-year-old seedlings of abies balsamea (l.) mill, picea glauca (moench) voss, pinus contorta loudon, betula papyrifera marsh., populus tremuloides michx. and populus balsamifera l. were transplanted in the spring, in pots, to the understory of a mixed p. tremuloides-p. balsamifera stand or to an adjacent open site. growth and leaf characteristics were measured and photosynthetic light response curves determined in mid-august. overall, the coniferous seedlings showed less photosynthetic plastic ... | 2001 | 11276418 |
| spectral reflectance of picea rubens (pinaceae) and abies balsamea (pinaceae) needles along an elevational gradient, mt. moosilauke, new hampshire, usa. | relationships among elevation, foliar morphology, spectral reflectance, and chlorophyll fluorescence of two co-occurring montane conifers, red spruce (picea rubens sarg.) and balsam fir (abies balsamea [l.] mill.), were investigated along two transects from 460 to 1460 m on mt. moosilauke in the white mountains of new hampshire, usa. spectral reflectance (300-1100 nm wavelengths) and the chlorophyll fluorescence f(v)/f(m) ratio were measured on dark-adapted needles. foliar morphology (needle siz ... | 2001 | 11302853 |
| increasing the sink:source balance enhances photosynthetic rate of 1-year-old balsam fir foliage by increasing allocation of mineral nutrients. | to determine the impact of altering the sink:source balance on gas exchange rates in 1-year-old foliage of balsam fir (abies balsamea (l.) mill.), seedlings were either debudded before the growing season began or left intact. to assess alternative explanations for the observed photosynthetic response, additional seedlings were variously root pruned, shaded, drought stressed or deprived of fertilizer in combination with debudding. foliar gas exchange rates and carbohydrate concentrations, xylem w ... | 2001 | 11340042 |
| chemical characterization of fine particle emissions from fireplace combustion of woods grown in the northeastern united states. | a series of source tests was conducted to determine the chemical composition of fine particle emissions from the fireplace combustion of six species of woods grown in the northeastern united states: red maple, northern red oak, paper birch, eastern white pine, eastern hemlock, and balsam fir. results include fine particle emission rates for total mass, organic and elemental carbon, ionic species, elemental species including potassium, and over 250 specific organic compounds. the data are intende ... | 2001 | 11452590 |
| importance of needle age and shoot structure on canopy net photosynthesis of balsam fir (abies balsamea): a spatially inexplicit modeling analysis. | we have developed a spatially inexplicit model of canopy photosynthesis for balsam fir (abies balsamea (l.) mill.) that accounts for key processes of light-shoot interaction including irradiance interception by the shoot, spatial aggregation of shoots into branches and crowns, the differential propagation of diffuse and direct light within the canopy, and an ideal representation of penumbra. also accounted for in the model are the effects of the average radiative climate and shoot age on needle ... | 2001 | 11498329 |
| pervasive influence of large-scale climate in the dynamics of a terrestrial vertebrate community. | large-scale climatic variability has been implicated in the population dynamics of many vertebrates throughout the northern hemisphere, but has not been demonstrated to directly influence dynamics at multiple trophic levels of any single system. using data from isle royale, usa, comprising time series on the long-term dynamics at three trophic levels (wolves, moose, and balsam fir), we analyzed the relative contributions of density dependence, inter-specific interactions, and climate to the dyna ... | 2001 | 11782292 |
| fate of spinosad in litter and soils of a mixed conifer stand in the acadian forest region of new brunswick. | spinosad is a natural insecticide, produced via fermentation culture of the actinomycete saccharopolyspora spinosa, with potential use against a number of forest pests including spruce budworm (choristoneura fumiferana [clem]). persistence of spinosad was determined in terrestrial fate experiments conducted within a semimature stand of black spruce (picea mariana [mill.]) and balsam fir (abies balsamea [l]) in the acadian forest region of new brunswick, canada. results of experiments established ... | 2002 | 11829646 |
| gravimorphism in current-year shoots of abies balsamea: involvement of compensatory growth, indole-3-acetic acid transport and compression wood formation. | we investigated the cause of gravimorphic growth inhibition in current-year shoots of balsam fir (abies balsamea (l.) mill.) seedlings displaced from their normal orientation in the gravitational field. tilting the main stem of seedlings decreased shoot elongation, cambial growth as measured by tracheid production, and leaf dry weight of the terminal shoot and the lateral shoots on the lower side of the tilted stem. removing either the terminal shoot or all lateral shoots induced compensatory gr ... | 2002 | 11960755 |
| fate of spinosad in litter and soils of a white spruce plantation in central ontario. | spinosad is a natural insecticide with potential as a novel biorational control agent for spruce budworm (choristoneura fumiferana [clem]), the most destructive insect defoliator of spruce and balsam fir in canada. concurrent terrestrial fate experiments were conducted under full coniferous canopy and in a natural opening of a mature white spruce (piecea glauca [moench]) plantation of central ontario to examine the fate and persistence of spinosad in the forest floor and underlying soils. mean i ... | 2002 | 11975189 |
| changes in foliar spectral reflectance and chlorophyll fluorescence of four temperate species following branch cutting. | spectral reflectance and chlorophyll fluorescence are rapid non-invasive methods that can be used to quantify plant stress. because variation in ambient light (e.g., diurnal patterns of solar radiation) may have a confounding effect on these measurements, branches are often excised in the field and then measured under controlled conditions in the laboratory. we studied four temperate tree species (abies balsamea (l.) mill. (balsam fir), betula papyrifera var. cordifolia (regel) fern. (paper birc ... | 2002 | 11986053 |
| does nutrition-related stress carry over to spruce budworm, choristoneura fumiferana (lepidoptera: tortricidae) progeny? | three different patterns of feeding of sixth-instar spruce budworm, choristoneura fumiferana clemens were simulated in the laboratory. larvae were fed artificial diets whose nitrogen and total soluble sugar contents varied according to levels similar to those found in three types of balsam fir, abies balsamea (l.) miller foliage (current-year foliage from middle and lower crown sections and one-year-old foliage). the biological performance of offspring was studied according to the nutrition of t ... | 2002 | 12020367 |
| mercury levels in lichens from different host trees around a chlor-alkali plant in new brunswick, canada. | mercury concentrations were determined in the epiphytic lichen hypogymnia physodes along five transects starting from a chlor-alkali plant located at dalhousie, new brunswick, a landfill site and a nearby electricity generating station. lichen samples were collected from white birch (betula papyrifera) and spruce (picea sp.) or balsam fir (abies balsamea). average lichen background mercury values were 0.088+/-0.005 microg/g from white birch and 0.148+/-0.046 microg/g from spruce trees, with a de ... | 2002 | 12109479 |
| lethal and sublethal effects of a neem-based insecticide on balsam fir sawfly (hymenoptera: diprionidae). | lethal and sublethal effects of neemix 4.5 ec, a commercial neem preparation, on balsam fir sawfly, neodiprion abietis (harris), were determined in the laboratory. larval mortality of n. abietis increased in a concentration-dependent manner, and lethal time decreased with increasing neemix 4.5 ec concentration. fifty percent of the larvae died after 4.6 d at a concentration of 90 ppm azadirachtin (aza) and 12.3 d at a concentration of 0.08 ppm. neemix 4.5 ec showed some deterrent effects to feed ... | 2003 | 12650342 |
| ethylene evolution, radial growth and carbohydrate concentrations in abies balsamea shoots ringed with ethrel. | the terminal (1-year-old) shoot of quiescent, 2-year-old abies balsamea (l.) mill. seedlings was either left untreated or ringed with 0, 1 or 10 mg ethrel g(-1) lanolin. after 5 weeks of culture under environmental conditions favorable for growth, the shoots were harvested to measure ethylene evolution and carbohydrate concentrations by gas chromatography, and tracheid number and bark radial width by microscopy. in untreated shoots, the basal rate of ethylene evolution followed the order: cambia ... | 1998 | 12651363 |
| advantages of a mixed diet: feeding on several foliar age classes increases the performance of a specialist insect herbivore. | two field studies were carried out to determine the influence of abies balsamea foliage age on the preference and performance of larvae of neodiprion abietis, a specialist diprionid sawfly. preference was determined by examining n. abietis defoliation on all age classes of foliage. performance was estimated using larval survival, cocoon weights and the percentage of adults that were females. neodiprion abietis preference for, and performance on, current-year foliage was very low, peaked on 2 or ... | 2003 | 12721829 |
| antitumor activity of balsam fir oil: production of reactive oxygen species induced by alpha-humulene as possible mechanism of action. | the antitumor activity of the essential oil of abies balsamea (balsam fir oil) was evaluated against several solid tumor cell lines including mcf-7, pc-3, a-549, dld-1, m4beu and ct-26. balsam fir oil was found to be active against all the solid tumor cell lines tested, with gi 50 values ranging between 0.76 and 1.7 mg/ml. the oil was analyzed by gc-ms and the cytotoxicity of each oil constituent was determined. balsam fir oil is essentially constituted of monoterpenes tau; 96 %) and some sesqui ... | 2003 | 12802719 |
| cloud water and throughfall deposition of mercury and trace elements in a high elevation spruce-fir forest at mt. mansfield, vermont. | as part of the lake champlain basin watershed study of mercury (hg) and pollutant deposition, cloud water and cloud throughfall collections were conducted at the south summit (1204 m) of mt. mansfield, vermont between august 1 and october 31, 1998, for multi-element chemical analysis. a passive teflon string collector was deployed during non-precipitating events to sample cloud/fog water at timberline, while three sets of paired funnels collected cloud throughfall under the red spruce-balsam fir ... | 2003 | 12948231 |
| constituents within pulp mill effluent deplete retinoid stores in white sucker and bind to rainbow trout retinoic acid receptors and retinoid x receptors. | wild female and male white sucker (catostomus commersoni) inhabiting an area receiving pulp mill effluent had reduced hepatic levels of retinol, didehydroretinol, retinyl esters, and didehydroretinyl esters, while vitamin e levels were unaffected. this disruption of the retinoid system led us to test methanol and dichloromethane extracts from the effluent of 11 pulp mills from across canada for their ability to bind to rainbow trout (oncorhynchus mykiss) retinoic acid receptors (rars) from the g ... | 2003 | 14713038 |
| seasonal and annual changes in soil respiration in relation to soil temperature, water potential and trenching. | soil respiration (rs), soil temperature (ts) and volumetric soil water content were measured in a balsam fir (abies balsamea (l.) mill.) ecosystem from 1998 to 2001. seasonal variation in root and microbial respiration, and covariation in abiotic factors confounded interpretation of the effects of ts and soil water potential (psis) on rs. to minimize the confounding effect of temperature, we analyzed the effect of psis on rs during the summers of 1998-2000 when changes in ts were slight. soil re ... | 2004 | 14757581 |
| crown architecture of abies balsamea from four canopy positions. | data collected from four distinct canopy positions from each of 39 abies balsamea (l.) miller trees were used to construct models to describe the cumulative leaf area distribution within the crown and to predict the needle mass of individual branches, the average branch angle, branch diameter, branch length, and crown radius per whorl, and the average number of living branches per whorl. we tested the hypotheses that regression models are equal among canopy positions and that a model to predict ... | 1997 | 14759876 |
| estimating stem maintenance respiration rates of dissimilar balsam fir stands. | stem maintenance respiration rates were measured in five contrasting balsam fir (abies balsamea (l.) mill.) stands. at 15 degrees c, average respiration rates for individual stands ranged from 120 to 235 micro mol m(-3) s(-1) when expressed per unit of sapwood volume, from 0.80 to 1.80 micro mol m(-2) s(-1) when expressed per unit of stem surface area, and from 0.50 to 1.00 micro mol g(-1) s(-1) when expressed per unit of nitrogen in the living stem biomass, but differences among stands were not ... | 1996 | 14871691 |
| laterally applied ethrel causes local increases in radial growth and indole-3-acetic acid concentration in abies balsamea shoots. | the terminal (1-year-old) shoot of quiescent, two-year-old balsam fir (abies balsamea (l.) mill.) seedlings was ringed with lanolin containing 0, 1 or 10 mg g(-1) ethrel, an ethylene-generating compound, and cultured for 6 weeks under environmental conditions favorable for growth. bud break and the elongation of the current-year terminal shoot were monitored, and the subjacent previous-year terminal shoot that had been treated with ethrel was harvested to measure stem radial growth by microscopy ... | 1996 | 14871721 |
| interaction between indole-3-acetic acid and ethylene in the control of tracheid production in detached shoots of abies balsamea. | we investigated the interaction between indole-3-acetic acid (iaa) and ethylene in the regulation of the seasonal periodicity of tracheid production in 1-year-old balsam fir (abies balsamea (l.) mill.) cuttings collected at different times during the dormant period. the cuttings were left with their buds intact or were debudded and treated either apically with iaa or 2-chloroethylphosphonic acid (ethrel) in lanolin, laterally with iaa or ethrel in lanolin, or basally with ethrel, co(2+) or ag(+) ... | 1995 | 14966008 |
| canopy dynamics and the morphological development of abies balsamea: effects of foliage age on specific leaf area and secondary vascular development. | data were collected from two branches from each whorl of nine open-grown abies balsamea (l.) miller trees to test the hypothesis that specific leaf area (sla, m(2) projected fresh leaf area kg(-1) oven-dry foliage) is constant among five foliage age classes (current-year, 1-year-old, 2-year-old, 3-year-old and 4-year-old-plus). between-tree variation in sla was greater than within-tree variation. differences in sla among the foliage age classes were small, but statistically significant, showing ... | 1995 | 14966011 |
| a comparison of red spruce and balsam fir shoot structures. | i compared the shoot structures of high-elevation red spruce (picea rubens sarg.) and balsam fir (abies balsamea (l.) mill.). needle widths, thicknesses and perimeters were measured to estimate total leaf areas from measured projected leaf areas. measured needle perimeter/needle width ratios differed significantly from estimated ratios that assumed needles were either rhomboidal or elliptical in cross section. the vertical and horizontal silhouette shoot area to total leaf area ratios (star(v) a ... | 1993 | 14969913 |
| neutralization and buffering capacity of leaves of sugar maple, largetooth aspen, paper birch and balsam fir. | we compared the acidity, the external acid neutralizing capacity and the buffering capacity of leaves of four commercially important tree species, largetooth aspen (populus grandidentata michx.), sugar maple (acer saccharum marsh.), paper birch (betula papyrifera marsh.) and balsam fir (abies balsamea (l.) mill), at two sites of contrasting soil fertility in southern quebec. external acid neutralizing capacity (enc) of leaves was determined by measuring the change in ph induced by soaking fresh ... | 1993 | 14969931 |
| auxin and ethylene regulation of diameter growth in trees. | recent studies on the phytohormonal regulation of seasonal cell-division activity in the cambium, primary-wall radial expansion of cambial derivatives, differentiation of xylem cells, and growth of the cortex in forest trees of the north temperate zone are reviewed. indol-3-ylacetic acid (iaa, auxin) has been characterized by combined gas chromatography-mass spectrometry (gc-ms) in the cambial region of abies balsamea, pinus densiflora, pinus sylvestris and quercus robur. all of the evidence sup ... | 1988 | 14972810 |
| changes in the water relations of balsam fir and white birch saplings after thinning. | in the autumn of 1987, young balsam fir (abies balsamea (l.) mill.) and white birch (betula papyrifera marsh.) trees were thinned and their water relations followed during the next two growing seasons. at the beginning of the first summer following treatment, thinned trees of both species had lower osmotic potentials at full saturation (psi(pi,sat)) and at turgor loss point (psi(pi,tlp)) compared with controls. at this time, psi(pi,sat) was linearly related to the percentage of full sunlight rea ... | 1990 | 14972929 |
| a method for reconstructing the development of the sapwood area of balsam fir. | leaf area is commonly estimated as a function of sapwood area. however, because sapwood changes to heartwood over time, it has not previously been possible to reconstruct either the sapwood area or the leaf area of older trees into the past. in this study, we report a method for reconstructing the development of the sapwood area of dominant and codominant balsam fir (abies balsamea (l.) mill.). the technique is based on establishing a species-specific relationship between the number of annual gr ... | 1990 | 14972939 |
| differences in stem respiration responses to temperature between balsam fir trees in thinned and unthinned stands. | the change in stem respiration rates with change of temperature was significantly lower in a recently thinned balsam fir (abies balsamea (l.) mill.) stand than in an unthinned stand. a comparison of respiration measurements made in the morning with those made in the afternoon indicated that there was more variation among afternoon readings and greater responses to changes in temperature among morning readings. lower respiration rates in the afternoon were more common in the thinned stand than in ... | 1987 | 14975815 |
| an effect of gravity on bud-burst in balsam fir. | bud-burst on first order lateral branches of abies bafsamea l. (balsam fir) was delayed when the branches were rotated 180 degrees about their long axis. this was not a consequence of injury caused by the treatment because buds rotated 180 degrees on inverted plants flushed at the same time as the controls, whereas flushing of all other buds was delayed. buds thus appear to be more vigorous when maintained in the same orientation to gravity in which they are formed and the site of gravitational ... | 1986 | 14975906 |
| design and evaluation of an aerial spray trial with true replicates to test the efficacy of bacillus thuringiensis insecticide in a boreal forest. | a field trial using true replicates was conducted successfully in a boreal forest in 1996 to evaluate the efficacy of two aerially applied bacillus thuringiensis formulations, abg 6429 and abg 6430. a complete randomized design with four replicates per treatment was chosen. twelve to 15 balsam fir (abies balsamea [l.] mill.) per plot were randomly selected as sample trees. interplot buffer zones, > or = 200 m wide, adequately prevented cross contamination from sprays that were atomized with four ... | 2003 | 14994805 |
| the influence of top-down, bottom-up and abiotic factors on the moose (alces alces) population of isle royale. | long-term, concurrent measurement of population dynamics and associated top-down and bottom-up processes are rare for unmanipulated, terrestrial systems. here, we analyse populations of moose, their predators (wolves, canis lupus), their primary winter forage (balsam fir, abies balsamea) and several climatic variables that were monitored for 40 consecutive years in isle royale national park (544 km2), lake superior, usa. we judged the relative importance of top-down, bottom-up and abiotic factor ... | 2004 | 15058396 |
| bacillus thuringiensis subsp. kurstaki aerial spray prescriptions for balsam fir stand protection against spruce budworm (lepidoptera: tortricidae). | although commercial formulations of bacillus thuringiensis subsp. kurstaki (btk) are being widely used in forest protection against lepidopteran defoliators, optimal application prescriptions have often yet to be worked out in detail. we conducted field experiments over a 6-yr period (1996-2001) in southwestern québec to determine application prescriptions for optimal protection of balsam fir, abies balsamea (l.), healthy stands against the spruce budworm, choristoneura fumiferana (clemens) (lep ... | 2004 | 15568352 |
| interacting influence of light and size on aboveground biomass distribution in sub-boreal conifer saplings with contrasting shade tolerance. | plant size often influences shade tolerance but relatively few studies have considered the functional response of taller plants to contrasting light environments. several boreal and sub-boreal abies, picea and pinus species were studied along a light (0-90% full sunlight) and size (30-400-cm high) gradient to examine the interactive influence of tree size and light availability on aboveground biomass distribution. sampling was conducted in two regions of canada: (a) british columbia, for abies l ... | 2005 | 15631985 |
| epiphytic lichen diversity on dead and dying conifers under different levels of atmospheric pollution. | based on literature data, epiphytic lichen abundance was comparably studied in montane woodlands on healthy versus dead or dying conifers of europe and north america in areas with different levels of atmospheric pollution. study sites comprised picea abies forests in the harz mountains and in the northern alps, germany, picea rubens-abies balsamea forests on whiteface mountain, adirondacks, new york, u.s.a. and picea engelmannii-abies lasiocarpa forests in the salish mountains, montana, u.s.a. d ... | 2005 | 15701398 |
| carbon and biomass partitioning in balsam fir (abies balsamea). | balsam fir (abies balsamea (l.) mill) was extensively sampled to investigate the effects of forest management practices, site location, within-crown position, tree component (i.e., stem, foliage, branches and roots), and tree social classes on biomass and carbon (c) partitioning at the individual tree level and across ecological regions. the sites were located in three ecologically distinct forest regions of west-central new brunswick, canada. there were no significant differences in %c content ... | 2005 | 15996964 |
| virulence of a nucleopolyhedrovirus to neodiprion abietis (hymenoptera: diprionidae). | different larval stages of balsam fir sawfly, neodiprion abietis (harris) (hymenoptera: diprionidae), were challenged by different concentrations of a nucleopolyhedrovirus in the laboratory to determine larval susceptibility to the virus and to test treatment effects of the virus on the sawfly survivors. the results indicated that younger larvae were more susceptible to the virus than older instars. the speed of larval death depended on the larval age and the virus concentration. generally, the ... | 2005 | 16539106 |
| influence of larval stage and virus inoculum on virus yield in insect host neodiprion abietis (hymenoptera: diprionidae). | virus yield produced by dead larvae of balsam fir sawfly, neodiprion abietis (harris) (hymenoptera: diprionidae), that had been infected at four different larval stages (second, third, fourth, or fifth instar) with two virus concentrations (10(5) polyhedral inclusion bodies (pib) /ml or 10(7) pib/ml), were analyzed and compared to determine the effects of instar and amount of virus inoculum on virus production. the results indicate that both larval stage and inoculation dosage significantly affe ... | 2005 | 16539107 |
| dark respiration rate increases with plant size in saplings of three temperate tree species despite decreasing tissue nitrogen and nonstructural carbohydrates. | in shaded environments, minimizing dark respiration during growth could be an important aspect of maintaining a positive whole-plant net carbon balance. changes with plant size in both biomass distribution to different tissue types and mass-specific respiration rates (r(d)) of those tissues would have an impact on whole-plant respiration. in this paper, we evaluated size-related variation in r(d), biomass distribution, and nitrogen (n) and total nonstructural carbohydrate (tnc) concentrations of ... | 2006 | 16585037 |
| composition and antibacterial activity of abies balsamea essential oil. | the antibacterial activity of the essential oil of abies balsamea (balsam fir) was evaluated against escherichia coli and staphylococcus aureus. the essential oil of a. balsamea was found to be inactive against e. coli (>100 microg/ml) and active against s. aureus, with an mic of 56 microg/ml. the oil composition was analysed by gc-ms and the antibacterial activity of each oil constituent was determined. the essential oil of a. balsamea is essentially constituted of monoterpenes (>96%) and some ... | 2006 | 16619365 |
| relationships between stand composition and ectomycorrhizal community structure in boreal mixed-wood forests. | we investigated the community structure of ectomycorrhizal fungi under varying overstory tree compositions in the southern mixed-wood boreal forest of quebec. sampling took place at two locations of differing postfire ages and nine 100-m2 plots were sampled per location. the dominant overstory tree species in the plots were trembling aspen (populus tremuloides michx.), white birch (betula papyrifera marsh.) or white spruce [picea glauca (moench) voss], and balsam fir [abies balsamea (l.) mill.]. ... | 2006 | 16699911 |
| sequence analysis and organization of the neodiprion abietis nucleopolyhedrovirus genome. | of 30 baculovirus genomes that have been sequenced to date, the only nonlepidopteran baculoviruses include the dipteran culex nigripalpus nucleopolyhedrovirus and two hymenopteran nucleopolyhedroviruses that infect the sawflies neodiprion lecontei (nelenpv) and neodiprion sertifer (nesenpv). this study provides a complete sequence and genome analysis of the nucleopolyhedrovirus that infects the balsam fir sawfly neodiprion abietis (hymenoptera, symphyta, diprionidae). the n. abietis nucleopolyhe ... | 2006 | 16809301 |
| forest dynamics after successive spruce budworm outbreaks in mixedwood forests. | in order to assess the long-term spatiotemporal influence of the spruce budworm in sub-boreal mixedwood forests, we studied the effect of three successive outbreaks in a region of western quebec, canada. we used dendrochronology to detect past outbreaks in three areas (111-185 ha), based on the recruitment age of balsam fir (abies balsamea) and on growth patterns of white spruce (picea glauca), the two main host species of this defoliating insect. we also used a series of aerial photographs take ... | 2006 | 16995632 |
| paleoecological assessment of watershed history in primenet watersheds at acadia national park, usa. | paleoecological reconstructions of forest stand histories for two upland watersheds at acadia national park in maine were completed to support related watershed chemistry studies. the project hypothesis was that forest type and fire history influence long-term cycling and storage of atmospheric mercury and nitrogen within watersheds. the reconstructions document differences in major vegetation composition and disturbance between the burned and unburned watersheds during the past several centurie ... | 2007 | 17057985 |
| diversity of the small subunit ribosomal rna gene of the arbuscular mycorrhizal fungi colonizing clintonia borealis from a mixed-wood boreal forest. | arbuscular mycorrhizal fungi (amf) communities in clintonia borealis roots from a boreal mixed forests in northwestern québec were investigated. roots were sampled from 100 m2 plots whose overstory was dominated by either trembling aspen (populus tremuloides michx.), white birch (betula papyrifera marsh.), or mixed white spruce (picea glauca (moench) voss) and balsam fir (abies balsamea (l.) mill.). part of the 18s ribosomal gene of the amf was amplified and the resulting pcr products were clone ... | 2006 | 17064264 |
| interannual consistency in canopy stomatal conductance control of leaf water potential across seven tree species. | we investigated interannual variability of canopy transpiration per unit ground area (e (c)) and per unit leaf area (e (l)) across seven tree species in northern wisconsin over two years. these species have previously been shown to be sufficient to upscale stand-level transpiration to the landscape level during one growing season. our objective was to test whether a simple plant hydraulic model could capture interannual variation in transpiration. three species, wetland balsam fir (abies balsame ... | 2007 | 17169902 |
| geographic biotype and host-associated local adaptation in a polyphagous species, lambdina fiscellaria (lepidoptera: geometridae) feeding on balsam fir on anticosti island, canada. | the debate about mechanisms underlying the evolution of host specialization by herbivorous insects remains open. natural selection may act locally and lead to different patterns of geographic variation in life history traits of polyphagous herbivores. the hypothesis of genetically-based trade-offs in offspring performance on different hosts has been proposed but this has rarely been demonstrated. under laboratory conditions, the biological performance of two populations of the hemlock looper lam ... | 2006 | 17201980 |
| comparative use of mindarus abietinus (homoptera: aphididae) by two coccinellids (coleoptera: coccinellidae), the native anatis mali and the exotic harmonia axyridis, in a christmas tree plantation. | the exotic coccinellid harmonia axyridis (pallas) recently expanded its range into eastern canada and elsewhere in north america. we hypothesized that this coccinellid should be less well adapted to the prey mindarus abietinus koch. on balsam fir trees than the native coccinellid anatis mali (say), which evolved in close association with aphids on conifers in north america. we compared, under field conditions, prey use by both species by collecting data on their synchrony with m. abietinus, thei ... | 2007 | 17445366 |
| in vivo replication kinetics and transcription patterns of the nucleopolyhedrovirus (neabnpv) of the balsam fir sawfly, neodiprion abietis. | dna replication and transcription of neabnpv, the nucleopolyhedrovirus (npv) of the balsam fir sawfly, neodiprion abietis (hymenoptera: diprionidae), in host larvae were investigated. npv dna replication kinetics and gene-expression patterns have been resolved only in lepidopteran cell-culture systems and in limited in vivo experiments with lepidopteran larvae. furthermore, there are significant differences in pathologies caused by lepidopteran npvs, which replicate in many tissues, and hymenopt ... | 2007 | 17554027 |
| developmental polymorphism in a newfoundland population of the hemlock looper, lambdina fiscellaria (lepidoptera: geometridae). | the hemlock looper [lambdina fiscellaria (guenée)], a widespread and highly polyphagous geometridae, is considered one of the most economically important defoliators of north american coniferous forests. variations in the number of larval instars between geographic populations of this species have been previously reported in the literature. however, whether such developmental polymorphism occurs within a given population is unknown. in this study, we report the presence of both four and five lar ... | 2007 | 17716462 |
| natural disturbance and the steady state in high-altitude balsam fir forests. | wind-induced, cyclic waves of death, regeneration, and maturation constantly move through the high-altitude balsam fir forests in the northeastern united states. biomass and productivity relations, species diversity, and nutrient cycling patterns are closely tied to this cycle of disturbance. disturbance is thus an integral part of the long-term maintenance of this ecosystem. since forests of this type normally include all phases of the disturbance-regeneration cycle, they may constitute a stead ... | 1981 | 17748274 |
| cloud droplet deposition in subalpine balsam fir forests: hydrological and chemical inputs. | subalpine forests of the northern appalachians are subject to significant deposition of water and chemicals via cloud droplet impaction. this deposition has been estimated by a method linking micrometeorological measures of turbulent transfer, a detailed representation of canopy structure, and experimentally derived capture efficiencies. water inputs from clouds are about 46 percent, and chemical inputs range from 150 to 430 percent of the bulk precipitation. | 1982 | 17770164 |
| identity of a fungus causing blue stain in balsam fir. | blue-stained balsam fir wood [abies balsamea (l.) mill.] consistently yielded cultures of a nonsporulating fungus which were found to be the same as those obtained from ascospores of amphisphaeria thujina (peck) sacc. collected from dead branches of this host. this blue stain appears to be identical with a previously reported but hitherto unidentified stain of conifers. the association of amphisphaeria with stain in living trees does not appear to have been recognized before. | 1961 | 17814562 |
| erratum. | in the report "cloud droplet deposition in subalpine balsam fir forests: hydrological and chemical inputs" by g. m. lovett et al. (24 dec., p. 1303), two errors appeared in table 2 on page 1304. the cloud deposition of so(4)(2-), incorrectly reported as 275.8 kg ha(-1) year(-1), should have been 137.9 kg ha(-1) year(-1). the percentage of the sum contributed by clouds, reported as 81 for so(4)(2-), should have been 68. | 1983 | 17831392 |
| distribution and hosts of callidiellum rufipenne (coleoptera: cerambycidae), an asian cedar borer established in the eastern united states. | the distribution and hosts of the exotic cedar-boring beetle, callidiellum rufipenne (motschulsky) (coleoptera: cerambycidae), were determined in five northeastern u.s. states by capturing adults on cedar trap logs and by rearing adults from various conifers. this beetle was detected in the coastal states of massachusetts, rhode island, connecticut, new york, and new jersey. in these states, adults emerged from the live or dead wood of four genera and eight species of cupressaceae; species of pi ... | 2007 | 17849882 |
| plant community influences on soil microfungal assemblages in boreal mixed-wood forests. | we studied the relationships between assemblages of soil microfungi and plant communities in the southern boreal mixed-wood forests of quebec. sampling took place in 18,100 m2 plots from an existing research site. plots were separated into three categories based on dominant overstory tree species: (i) trembling aspen, (ii) white birch and (iii) a mixture of white spruce and balsam fir. within each plot a 1 m2 subplot was established in which the understory herbaceous layer was surveyed and soil ... | 2007 | 17883027 |
| kinetic characterization for dilute sulfuric acid hydrolysis of timber varieties and switchgrass. | hydrolysis of four timber species (aspen, balsam fir, basswood, and red maple) and switchgrass was studied using dilute sulfuric acid at 50 g dry biomass/l under similar conditions previously described as acid pretreatment. the primary goal was to obtain detailed kinetic data of xylose formation and degradation from a match between a first order reaction model and the experimental data at various final reactor temperatures (160-190 degrees c), sulfuric acid concentrations (0.25-1.0% w/v), and pa ... | 2008 | 17904838 |
| element mobility and partitioning along a soil acidity gradient in central ontario forests, canada. | the potential environmental risk posed by metals in forest soils is typically evaluated by modeling metal mobility using soil-solution partitioning coefficients (k(d)), although such information is generally restricted to a few well-studied metals. soil-solution partitioning coefficients were determined for 17 mineral elements (al, as, be, ba, ca, cr, cu, fe, ga, k, li, mg, rb, sr, tl, u and v) in a-horizon (0-5 cm) soil at 46 forested sites that border the precambrian shield in central ontario, ... | 2008 | 18058024 |
| spectral analysis of coniferous foliage and possible links to soil chemistry: are spectral chlorophyll indices related to forest floor dissolved organic c and n? | dissolved organic matter in soils can be predicted from forest floor c:n ratio, which in turn is related to foliar chemistry. little is known about the linkages between foliar constituents such as chlorophylls, lignin, and cellulose and the concentrations of water-extractable forest floor dissolved organic carbon and dissolved organic nitrogen. lignin and cellulose are not mobile in foliage and thus may be indicative of growing conditions during prior years, while chlorophylls respond more rapid ... | 2008 | 18191443 |
| modeling spruce budworm population revisited: impact of physiological structure on outbreak control. | understanding the dynamics of spruce budworm population is very important for the protection of spruce and balsam fir trees of north american forests, and a full understanding of the dynamics requires careful consideration of the individual physiological structures that is essential for outbreak control. a model as a delay differential equation is derived from structured population system, and is validated by comparing simulation results with real data from the green river area of new brunswick ... | 2008 | 18306004 |
| springtime resumption of photosynthesis in balsam fir (abies balsamea). | photosynthesis in balsam fir (abies balsamea (l.) mill.) was measured in the field at two locations in new brunswick, canada from late winter to late spring in 2004 and 2005. no photosynthesis was detectable while the soil remained below 0 degrees c throughout the rooting zone. in both years, photosynthesis began once soil temperature rose to 0 degrees c. in potted seedlings in growth chambers, there was no photosynthesis at an air temperature of 10 degrees c if the pots were frozen. these findi ... | 2008 | 18450571 |
| ecophysiology and growth of advance red spruce and balsam fir regeneration after partial cutting in yellow birch-conifer stands. | we investigated ecophysiological and growth responses of short (0.4 to 1.3 m in height) advance regeneration of red spruce (picea rubens sarg.) and balsam fir (abies balsamea l.) six years after removal of 0, 40, 50, 60 and 100% of the overstory basal area (ba) in two yellow birch-conifer stands. partial cuts significantly increased stomatal conductance of red spruce only. light-saturated photosynthesis (leaf-area basis) of both species increased with ba removal, but unlike red spruce, specific ... | 2008 | 18519253 |
| cambial activity and intra-annual xylem formation in roots and stems of abies balsamea and picea mariana. | studies on xylogenesis focus essentially on the stem, whereas there is basically no information about the intra-annual growth of other parts of the tree. as roots strongly influence carbon allocation and tree development, knowledge of the dynamics of xylem production and maturation in roots at a short time scale is required for a better understanding of the phenomenon of tree growth. this study compared cambial activity and xylem formation in stem and roots in two conifers of the boreal forest i ... | 2008 | 18708643 |
| impact of nutrient removal through harvesting on the sustainability of the boreal forest. | the cycling of base cations (k, ca, mg, and na) was investigated in a boreal balsam fir forest (the lake laflamme watershed) between 1999 and 2005. base cation budgets were calculated for the soil rooting zone that included atmospheric deposition and soil leaching losses, two scenarios of tree uptake (whole-tree and stem-only harvesting), and three scenarios of mineral weathering, leading to six different scenarios. in every scenario there was a net accumulation of mg within the soil exchangeabl ... | 2008 | 18839760 |
| genetic variability of canadian populations of the sapstain fungus ophiostoma piceae. | abstract genetic diversity was studied in seven canadian populations of ophiostoma piceae, the most prevalent sapstain fungus in canadian softwoods. a total of 239 single-spore isolates were recovered following a systematic survey of sapstain fungi in logs and lumber at seven selected sawmills in six canadian provinces (british columbia, alberta, saskatchewan, ontario, québec, and new brunswick). sampling was carried out on five commercially important softwood species: balsam fir (abies balsamea ... | 2001 | 18943849 |
| seasonal changes in abundance and phosphorylation status of photosynthetic proteins in eastern white pine and balsam fir. | during winter, the light-harvesting complexes of evergreen plants change function from energy-harvesting to energy-dissipating centers. the goal of our study was to monitor changes in the composition of the photosynthetic apparatus that accompany these functional changes. seasonal changes in chlorophyll fluorescence, pigment concentration, and abundance and phosphorylation status of photosynthetic proteins in pinus strobus l. (sun-exposed trees) and abies balsamea (l.) p. mill. (sun-exposed and ... | 2009 | 19203960 |
| wood formation in abies balsamea seedlings subjected to artificial defoliation. | we determined the cambial sensitivity and quantified the anatomical differences in xylem of abies balsamea (l.) mill. seedlings subjected to artificial defoliation to simulate spruce budworm feeding. defoliation was performed by removing two-thirds of needles of all current-year shoots for up to four consecutive growth cycles to account for inter- and intra-annual xylem formation. in experiment 1, xylem development was studied from may to october 2005 in seedlings defoliated at the end of june. ... | 2009 | 19203970 |
| host tree age as a selective pressure leading to local adaptation of a population of a polyphagous lepidoptera in virgin boreal forest. | we tested the hypothesis that host tree age may act as a selective factor and lead to local adaptation of the hemlock looper (lambdina fiscellaria), a geometrid lepidoptera that has a wide geographical distribution and has evolved in different eco-zones characterized by different levels of floristic composition, age structure and fragmentation level. considering that hemlock looper outbreaks mainly occurred in old forests, we compared the biological performances of two populations. the first pop ... | 2009 | 19224661 |
| genomic differences among pathotypes of bursaphelenchus xylophilus. | total genomic dna from bursaphelenchus xylophilus pathotypes mpsy-1 and vpst-1 and from b. mucronatus was digested with restriction endonucleases. dna fragments were electrophoretically separated, southern blotted to nitrocellulose, and hybridized to genomic dna from one of the isolates. the resulting hybridization patterns indicate genomic differences in repetitive dna sequences among these populations. greatest differences were seen between b. xylophilus and b. mucronatus, but genomic differen ... | 1988 | 19290214 |
| wood losses and economical threshold of btk aerial spray operation against spruce budworm. | spruce budworm, choristoneura fumiferana (clem.), causes cumulative defoliation and hence annual growth loss of the balsam fir, abies balsamea (l.) mill, host tree. annual growth increments of mixed balsam fir stands were measured by stem analysis over a 9 year period (1994-2002), when bacillus thuringiensis ssp. kurstaki (btk) was applied to control spruce budworm defoliation. with this approach, it was possible to quantify the change in stand volume growth after aerial spray applications of bt ... | 2010 | 19938000 |
| anti-insect secondary metabolites from fungal endophytes of conifer trees. | choristoneura fumiferana is the most economically-important insect pest in eastern north america. historically, strategies to control epidemics have relied on chemical pesticides that are no longer approved for use. the presence of fungal endophytes in cool area grass species and their role in reducing the impact of herbivorous insects is well understood. recent work has demonstrated that foliar endophytes of conifers also produce anti-insect toxins. field and nursery studies testing trees infec ... | 2009 | 19967982 |
| boring in response to bark and phloem extracts from north american trees does not explain host acceptance behavior of orthotomicus erosus (coleoptera: scolytidae). | when invasive herbivorous insects encounter novel plant species, they must determine whether the novel plants are hosts. the mediterranean pine engraver, orthotomicus erosus (wollaston), an exotic bark beetle poised to expand its range in north america, accepts hosts after contacting the bark. to test the hypothesis that o. erosus accepts hosts on the basis of gustatory cues, we prepared bark and phloem extracts from logs of four north american tree species that we had used in previous host acce ... | 2010 | 20388300 |
| forest restoration in a mixed-ownership landscape under climate change. | the extent to which current landscapes deviate from the historical range of natural variability (rnv) is a common means of defining and ranking regional conservation targets. however, climate-induced shifts in forest composition may render obsolete restoration strategies and conservation targets based on historic climate conditions and disturbance regimes. we used a spatially explicit forest ecosystem model, landis-ii, to simulate the interaction of climate change and forest management in northe ... | 2010 | 20405791 |
| optimization of spray drying process for bacillus thuringiensis fermented wastewater and wastewater sludge. | response surface methodology was used to optimize spray drying process for producing biopesticide powders of bacillus thuringiensis by using fermented broth of starch industry wastewater and wastewater sludge. analysis of variance was carried out using number of viable spores in the powder as dependent variable. the determination coefficients of models were 92 and 94% for fermented broth of starch industry wastewater and wastewater sludge, respectively. under the optimal conditions of the operat ... | 2011 | 20835715 |
| cree antidiabetic plant extracts display mechanism-based inactivation of cyp3a4. | seventeen cree antidiabetic medicinal plants were studied to determine their potential to inhibit cytochrome p450 3a4 (cyp3a4) through mechanism-based inactivation (mbi). the ethanolic extracts of the medicinal plants were studied for their inhibition of cyp3a4 using the substrates testosterone and dibenzylfluorescein (dbf) in high pressure liquid chromatography (hplc) and microtiter fluorometric assays, respectively. using testosterone as a substrate, extracts of alnus incana, sarracenia purpur ... | 2011 | 21186373 |
| species composition of saproxylic fungal communities on decaying logs in the boreal forest. | coarse woody debris supports large numbers of saproxylic fungal species. however, most of the current knowledge comes from scandinavia and studies relating the effect of stand or log characteristics on the diversity and composition of decomposer fungi have not been conducted in northeastern canada. logs from five tree species were sampled along a decomposition gradient in nine stands representing three successional stages of the boreal mixed forest of northwestern quebec, canada. using a molecul ... | 2011 | 21246195 |
| transcriptomic responses of the softwood-degrading white-rot fungus phanerochaete carnosa during growth on coniferous and deciduous wood. | to identify enzymes that could be developed to reduce the recalcitrance of softwood resources, the transcriptomes of the softwood-degrading white-rot fungus phanerochaete carnosa were evaluated after growth on lodgepole pine, white spruce, balsam fir, and sugar maple and compared to the transcriptome of p. carnosa after growth on liquid nutrient medium. one hundred fifty-two million paired-end reads were obtained, and 63% of these reads were mapped to 10,257 gene models from p. carnosa. five-hun ... | 2011 | 21441342 |
| host associations between fungal root endophytes and boreal trees. | fungal root endophytes colonize root tissue concomitantly with mycorrhizal fungi, but their identities and host preferences are largely unknown. we cultured fungal endophytes from surface-sterilized cenococcum geophilum ectomycorrhizae of betula papyrifera, abies balsamea, and picea glauca from two boreal sites in eastern canada. isolates were initially grouped on the basis of cultural morphology and then identified by internal transcribed spacer ribosomal dna sequencing or by pcr restriction fr ... | 2011 | 21475991 |
| effects of soil moisture manipulations on fine root dynamics in a mature balsam fir (abies balsamea l. mill.) forest. | we tested the hypothesis that moisture stress affects fine root dynamics during and after the stress. to this end, we investigated the effects of soil moisture on annual and seasonal fine root production and mortality over 4 years in a mature balsam fir (abies balsamea l. mill.) stand using a minirhizotron and soil coring. droughting and irrigating treatments were imposed for 17 weeks during the third year of the study, and post-treatment recovery was measured during the fourth year. monthly fin ... | 2011 | 21489968 |
| reproductive potential of balsam fir (abies balsamea), white spruce (picea glauca), and black spruce (p. mariana) at the ecotone between mixedwood and coniferous forests in the boreal zone of western quebec. | the reproductive potentials of balsam fir and white spruce (co-dominants in mixedwood forests) and black spruce (dominant in coniferous forests) were studied to explain the location of the ecotone between the two forest types in the boreal zone of quebec. four sites were selected along a latitudinal gradient crossing the ecotone. cone crop, number of seeds per cone, percentage filled seeds, and percentage germination were measured for each species. balsam fir and white spruce cone crops were sig ... | 2007 | 21636443 |
| genetic variation and population structure in central and isolated populations of balsam fir, abies balsamea (pinaceae). | genetic variation and spatial genetic structure in balsam fir (abies balsamea) were examined in two isolated populations in iowa and minnesota thought to be paleorefugia and in two ecologically central populations in old-growth forests of upper michigan. overall levels of genetic variability at 22 allozyme loci were lower than that found in most conifer species (h(o) values ranged from 0.005 in the isolated populations to 0.025 in the central populations). the mean f(is) value (0.154) was larger ... | 2002 | 21665678 |