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[A karyological study of swamp and dry valley populations of Siberian fir (Abies sibirica Ledeb.)].

The karyological data on populations of Siberian fir (Abies sibirica Ledeb.) growing in lowland swamp and dry valleys are given. The diploid set of both populations included 24 chromosomes (2n = 24). Polykaryogram analysis revealed seven pairs of metacentric and five pairs of submetacentric chromosomes. The revealed differences between the populations included the absolute length of chromosomes, number of nucleolar organizer regions, and number of nucleoli. Changed chromosome numbers (mixoploidy and aneuploidy) as well as chromosomal aberrations were recorded. For the first time, mitosis was studied in this species and anaphase/telophase aberrations were revealed. The population of Siberian fir growing under extreme conditions of lowland swamp featured the widest range of mutations.

Abies↗

PubMed2005

[Microbial diversity in continuously planted Chinese fir soil].

The study on the microbial diversity of 1st, 2nd, 3rd and 4th generation Chinese fir soil at Huitong Forest Experimental Station showed that with the increase of generation, the numbers of bacteria and actinomyces decreased markedly, while that of fungi increased evidently. It was found by PCR and DGGE that the bacterial diversity changed slightly and its genetic similarity among different generations reached 87 %, but the fungal diversity reduced and its genetic similarity was only 45%. The numbers of pathogenic and deleterious fungi increased markedly with increasing Chinese fir generations.

Actinomyces↗

PubMed1999

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 detect growth costs of reproduction and show how these translate into demographic costs when relative tree size (and therefore growth) is critical to survival. Using chronosequences, we reconstructed the age- and size-specific dynamics of a subalpine population of Abies balsamea. A matrix model describing these dynamics was then used to estimate age- and size-specific probabilities of future survival to maturity ([Formula: see text]). By using a regression model of the relationship between tree size, age, and [Formula: see text], we were able to estimate the maximum age-specific demographic cost of reproduction for trees of all ages. The shape of the age-specific cost curve for A. balsamea may explain why, contrary to a previously published hypothesis, age at first reproduction in A. balsamea does not vary between wave-regenerating and normal populations.

Abies balsamea↗

PubMed1996

Accuracy of least squares designed spatial FIR filters for segmentation of images of fluorescence stained cell nuclei.

A method for accurate, real-time image segmentation is needed for the development of a fully automated image cytometer that combines the speed and case-of-use of flow cytometry with the detailed morphometry of imaging. Object intensity variation and inherent optical blur make real-time segmentation challenging. The best spatial finite impulse response (FIR) filter, implemented as a convolution, was tested for sharpening edges and creating the required contrast. The filter and threshold segmentation steps were treated as a two-category linear classifier. Best 3 x 3 through 25 x 25 filters were designed utilizing the perceptron criterion and nonlinear least squares, and tested on ten montage images of a combined 1,070 manually segmented DAPI stained cell nuclei. The resulting image contrast, or class separation, led to simple automatic thresholding via the histogram intermodal minimum. Image segmentation accuracy began to plateau at 7 x 7 filters and did not increase above 15 x 15. Little loss in accuracy occurred with application to the images not used for design. This segmentation method provides a systematic, fast and accurate means of creating binary object maps useful for subsequent measurement, processing and cell classification.

3T3 Cells↗

PubMed1996

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-stranded RNA (dsRNA). The dsRNA banding pattern was similar to the electropherotype of cytoplasmic polyhedrosis virus type 5. CPV infections were found in 27 of 170 DFTM larvae reared from field collected egg masses from four of 10 sites examined in three geographic regions of British Columbia. The CPV-infection rate for the DFTM larvae ranged from 10 to 86% depending on the location of the site.

Journal Article↗

PubMed1998

Assignment and Power Series Analysis of the FIR Fourier Transform Spectrum of Cyanamide Using a Multimolecule Ritz Program.

The "Ritz" program, originally written for the analysis of the Fourier transform spectra of the methanol isotopomers and presented in previous papers, has been extended in order to analyze the spectra of other molecules. This program evaluates the term values involved in the assigned transitions by the Rydberg-Ritz combination principle, and can tackle such perturbations as Fermi-type resonances or Coriolis interactions. As a first application of the extended version, we present an investigation of the Fourier transform spectrum of cyanamide between 25 and 980 cm-1. More than 16 000 lines have been assigned. Our Ritz database now comprises a list of more than 19 000 assigned lines (including of the microwave and FIR lines available in the JPL database) and more than 3900 term values. All of the lines presented in this paper correspond to transitions within the ground and first excited inversion levels of the ground vibrational state of the small-amplitude modes. Copyright 1998 Academic Press.

Journal Article↗

PubMed2000

A Theoretical Study of the Methyl and Aldehyde Torsion FIR Spectra in Symmetric Propanal Isotopomers.

This paper is an extension of the techniques developed by us [A. Vivier-Bunge, V. H. Uc, and Y. G. Smeyers, J. Chem. Phys. 109, 2279 (1998)] for standard propanal. In that paper the potential energy surface for the simultaneous methyl and asymmetric aldehydic torsions was calculated at RHF/MP2 level using the 6-311(3df,p) basis set for propanal. The fit of the energy values to symmetry-adapted functional forms was carried out by using the 28 energy values which retain the C(3) dynamical symmetry of the methyl group in the optimization procedure. With this potential, as well as with the kinetic parameters and the electric dipole moment variations, the FIR frequencies and intensities for the methyl and aldehyde torsions of seven symmetric isotopomers of propanal were determined theoretically using two-dimensional calculations. The calculated spectra of propanal and three of its isotopomers were compared with the available experimental data. It is found that the calculations for the cis conformer satisfactorily reproduce the aldehyde and methyl torsion spectra and furnish also methyl torsionally excited progressions for the aldehyde torsion modes. The methyl torsion frequencies agree especially well whenever the methyl group is nondeuterated. The small deviations encountered for the deuterated compound are probably due to some mass effect, such as the zero-point vibrational energy correction, which is not taken into account in the present calculations. Finally, the influence of the deuteration on the intensities is discussed. Copyright 2000 Academic Press.

Journal Article↗

PubMed1990

Genetic analysis of forest tree populations: isolation of DNA from spruce and fir apices.

A method is described for the isolation of DNA from spruce and fir, starting with 3 to 5 apices (5 mg material). Apices are prepared manually from dormant buds harvested in summer and autumn, which are homogenized in 30 microliters buffer containing 1% SDS. The DNA is extracted with phenol and precipitated with ethanol. Agarose gel electrophoresis and Southern hybridization show that its molecular length is ca. 30-40 kb and that it is readily digested with various restriction enzymes. The method is very fast, it does not need CsCl centrifugation and is therefore suited for the analysis of large numbers of individual trees. Moreover, the buds can be collected all over the year. The yield of the method is up to 30 micrograms of high molecular weight DNA, enough to do several digests and hybridizations.

DNA↗

PubMed1994

On-line respiratory artefact removal via adaptive FIR filters in rheopneumographic measurement.

Impedance rheopneumography is a simple non-invasive technique that can reflect the vascular condition in the human pulmonary circulatory system. However, the much larger and almost in-banding respiratory artefact present has greatly restricted its usefulness to only respiratory patients of a less severe type, in view of the existing practice of requiring the subject to stop breathing momentarily during measurement. Conventional fixed or adaptive filtering cannot satisfactorily remove the artefact in view of the non-time stationary characteristic of the latter. In the paper, a fast adaptive FIR filter design method, which is based on the filter coefficient look-up table (CLT) concept, is presented as a solution. The CLT is constructed with the coefficients indexed to the cut-off frequency to separate the two components of the plethysmogram. An on-line fast Fourier transform is calculated to track the cut-off frequency. This filter can adaptively change its coefficients, not only for different subjects, but also for the same subject during long-term monitoring. Results show that this filter design is capable of providing an almost respiratory artefact-free signal for a majority of patients. The high speed of implementation also renders it a possibility for real-time monitoring applications.

Humans↗

PubMed1977

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 showed organogenesis. The soaked embryonic shoots formed new apical buds, with or without bud scales, adventitious dwarf needles or shoots, and root- and embryo-like structures. One of the embryos germinated and formed an irregular shoot. No differences were found between the various soak treatments, except that the 15-min water soak was ineffective. The 24-hr water soak was as effective as the 15-min growth regulator treatments.

Butyrates↗

PubMed2003

Effects of inbreeding on coastal Douglas fir growth and yield in operational plantations: a model-based approach.

In advanced generation seed orchards, tradeoffs exist between genetic gain obtained by selecting the best related individuals for seed orchard populations, and potential losses due to subsequent inbreeding between these individuals. Although inbreeding depression for growth rate is strong in most forest tree species at the individual tree level, the effect of a small proportion of inbreds in seed lots on final stand yield may be less important. The effects of inbreeding on wood production of mature stands cannot be assessed empirically in the short term, thus such effects were simulated for coastal Douglas fir [ Pseudotsuga menziesii var. menziesii (Mirb.) Franco] using an individual-tree growth and yield model TASS (Tree and Stand Simulator). The simulations were based on seed set, nursery culling rates, and 10-year-old field test performance for trees resulting from crosses between unrelated individuals and for inbred trees produced through mating between half-sibs, full-sibs, parents and offspring and self-pollination. Results indicate that inclusion of a small proportion of related clones in seed orchards will have relatively low impacts on stand yields due to low probability of related individuals mating, lower probability of producing acceptable seedlings from related matings than from unrelated matings, and a greater probability of competition-induced mortality for slower growing inbred individuals than for outcrossed trees. Thus, competition reduces the losses expected due to inbreeding depression at harvest, particularly on better sites with higher planting densities and longer rotations. Slightly higher breeding values for related clones than unrelated clones would offset or exceed the effects of inbreeding resulting from related matings. Concerns regarding the maintenance of genetic diversity are more likely to limit inclusion of related clones in orchards than inbreeding depression for final stand yield.

Analysis of Variance↗

PubMed2004

Response of zooplankton and phytoplankton communities to creosote-impregnated Douglas fir pilings in freshwater microcosms.

Creosote has been used extensively as an industrial wood preservative for the protection of marine pilings, railway ties, and utility poles and is a common source of polycyclic aromatic hydrocarbons (PAHs) into aquatic environments. At present, there is little information by which to judge the potential for creosote leached from impregnated pilings to cause toxicity to biota in aquatic environments. The objective of the current study was to assess the effects of creosote on zooplankton and phytoplankton populations in freshwater microcosms in relation to changes in the concentration and composition of PAHs leached from creosote-impregnated Douglas fir pilings during an 83-day exposure period. The study consisted of single microcosms containing one half, one, two, three, four, and six treated pilings. Two microcosms that received untreated pilings were used as controls. The total surface area of pilings in each microcosm was normalized by adding the appropriate number of untreated pilings. Samples were collected periodically between -14 and 83 days pre- and postexposure to determine aqueous concentrations of 15 priority PAHs and to assess the response of zooplankton and phytoplankton communities. Plankton community response to creosote was analyzed using principle responses curves. Peak aqueous concentrations of sigmaPAH occurred at day 7, ranging from 7.3 to 97.3 microg/L. Zooplankton abundance decreased in all microcosms after introduction of the impregnated pilings, with the magnitude of response varying as a function of aqueous creosote concentration. Using inverse regression, a no-observed-effect concentration for the zooplankton community of 11.1 microg/L was estimated. In contrast, algal abundance and diversity increased in all treatments between 7 and 21 days and attained levels up to twice that in control microcosms. This trend most likely reflected decreased grazing pressure because of the decrease in zooplankton populations, but it may also have reflected growth stimulation resulting from exposure to various constituents within the creosote mixture. Our results indicate that creosote leached from impregnated pilings deployed under typical conditions (e.g., wharves) may cause transient toxicity to benthic or limnetic communities shortly after deployment, but this likely poses few long-term risks to aquatic freshwater plankton communities.

Animals↗

PubMed2002

The influence of bark on the fermentation of Douglas-fir whitewood pre-hydrolysates.

Douglas-fir ( Pseudotsuga menziesii) whitewood was supplemented with increasing concentrations of bark (0-30%) and was pretreated using SO(2)-catalysed steam explosion. The presence of bark in the feedstock resulted in the decreased recovery of total sugars, furfural and 5-hydroxymethylfurfural in the resultant pre-hydrolysate. No detrimental impact on monomer sugar recovery was observed. The concentration of lipophilic extractives present in the pre-hydrolysate increased with increasing bark loading, to a maximum of 0.43 g x l(-1). The water-soluble pre-hydrolysates were fermented by Saccharomyces cerevisiae to determine the impact of bark on sugar consumption and ethanol production. Despite the inclusion of bark, fermentation of all pre-hydrolysates resulted in the complete consumption of hexose sugars within 48 h. Ethanol yields were greater than 0.43 g x g(-1) for all pre-hydrolysates regardless of bark content, indicating that, up to a content of 30%, bark had a negligible impact on the fermentation of the pre-hydrolysates to ethanol.

Biotechnology↗

PubMed2002

Measuring positive, negative, and null impacts of forest disturbances: a case study using dwarf mistletoe on Douglas fir.

Not all disease activity causes an impact. Not all impacts are negative. The aim of this study was to examine a method that could conceptually specify when impacts occur and that could quantify both negative and positive disease impacts. For this study, dwarf mistletoe ( Arceuthobium douglasi) of Douglas fir ( Pseudotsuga menziesii) in southwestern Oregon was used as a case study. The method uses six variables for forest growth, mortality, and stand structure, and six categorical disease severity scores. The impact model displays stands as points in multidimensional scaling space, where relative position is determined by values of the six stand variables. Positions in this two-dimensional space change when stand characteristics change. Differences associated with disease severity could be traced as trajectories, and impact was quantified using the length and direction of these trajectories. This multivariate impact assessment method was contrasted to impact assessments based on single variables. Methods based on multiple variables offer a useful way of characterizing impact on multiple objectives. The model indicates that dwarf mistletoe has positive, negative, and neutral impacts and that these could be illustrated and quantified using this method.

Models, Theoretical↗

PubMed2000

Characterization and expression of the Douglas-fir luminal binding protein (PmBiP).

The endoplasmic reticulum (ER) molecular chaperone, BiP, plays a role in the cotranslational translocation and subsequent folding and assembly of newly synthesized proteins targeted to the ER and secretory pathway. The sequence encoding a Douglas-fir (Pseudotsuga menziesii [Mirb] Franco) BiP homologue (PmBiP) was identified by differential screening of a seedling cDNA library. Southern blotting indicated that PmBiP is most likely present as a single copy. The deduced amino acid sequence of PmBiP contains an HEEL tetrapeptide sequence which functions to retain PmBiP in the ER and is different from HDEL commonly found in angiosperm plant BiPs. Amino acid sequence alignment and phylogenetic analysis show that PmBiP is highly similar to other plant BiPs yet forms a distinct phylogenetic subgroup which is separate from the angiosperm BiPs. Northern and western blotting revealed that PmBiP is subject to developmental regulation during seed development, germination, and early seedling growth and is seasonally regulated in needles of young seedlings.

Amino Acid Sequence↗

PubMed2005

(3Z,6Z,9Z, 12Z, 15Z)-Pentacosapentaene, a key pheromone component of the fir coneworm moth, Dioryctria abietivorella.

The sex pheromone of the fir coneworm moth consists of a blend of (3Z,6Z,9Z,12Z,15Z)-pentacosapentaene and (9Z, 11E)-tetradecadienyl acetate. Analogous blends of polyunsaturated, long-chain hydrocarbons with much shorter chain aldehydes or alcohols recently have been discovered in three other moth species in the superfamily Pyraloidea. These combinations of components from two distinct structural classes may represent an important and widespread new pheromone blend motif within the Lepidoptera.

Animals↗

PubMed1991

Characterization of the constitutive and wound-inducible monoterpene cyclases of grand fir (Abies grandis).

Monoterpene cyclase activity is greatly increased in grand fir (Abies grandis) sapling stems in response to wounding and the composition of the cyclic olefin mixture generated differs from that produced constitutively as determined by radio gas-liquid chromatography. Cell-free extracts from wounded stems and from non-wounded controls were systematically compared for monoterpene cyclase activities following partial purification and separation of these enzymes by anion-exchange chromatography (Mono Q FPLC) and native PAGE. The increase in monoterpene cyclase activity following wounding represents both the apparent enhancement of constitutive cyclase activities and the appearance of novel cyclization enzymes that are absent in nonwounded controls. A pinene cyclase was shown to be the major wound-inducible enzyme directly responsible for oleoresin monoterpene formation and was tentatively identified as a 62-kDa protein by SDS-PAGE.

Enzyme Induction↗

PubMed1992

Wound-inducible pinene cyclase from grand fir: purification, characterization, and renaturation after SDS-PAGE.

The major wound-inducible monoterpene synthase (cyclase) of grand fir (Abies grandis) stems transforms geranyl pyrophosphate to both (-)-alpha-pinene (40%) and (-)-beta-pinene (60%). The enzyme was purified to apparent homogeneity by anion-exchange and hydrophobic interaction chromatography, coupled to discontinuous native polyacrylamide gel electrophoresis at neutral pH and polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (also at neutral pH) followed by renaturation in 1% Tween 20 (polyoxyethylenesorbitan monolaurate). The renatured enzyme produced a mixture of isomeric pinenes from geranyl pyrophosphate identical to that generated by the native form. The protein exhibited a molecular weight of 63,000 by gel permeation chromatography and of 62,000 by denaturing gel electrophoresis, indicating that the monomer is active. The enzyme required Mn2+ (Km = 30 microM) for activity, exhibited a Km value of 6 microM for the substrate geranyl pyrophosphate, showed a pH optimum at 7.8 and temperature optimum at 42 degrees C, and was inhibited by pyrophosphate (I50 = 0.17 mM), orthophosphate (I50 = 51 mM), and alpha-pinene, as well as by the histidine-directed reagent diethylpyrocarbonate (I50 = 0.64 mM) and the cysteine-directed reagent p-hydroxymercuribenzoate (I50 = 1.9 microM). Although similar in many respects to constitutive monoterpene cyclases of herbaceous species, this inducible cyclase, the first enzyme of this type to be purified to homogeneity from a conifer, is distinguished by the relatively high pH optimum, and the strict specificity and high affinity for the divalent metal ion cofactor.

Cations, Divalent↗