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David I Dunstan - One of the best experts on this subject based on the ideXlab platform.
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germination of encapsulated embryos of interior spruce Picea glauca engelmannii complex and black spruce Picea mariana mill
Plant Cell Reports, 1993Co-Authors: Monika M Lulsdorf, T E Tautorus, Susan I Kikcio, Terry D Bethune, David I DunstanAbstract:Interior spruce (Picea glauca engelmannii complex) and black spruce (Picea mariana Mill.) cotyledonary somatic embryos were encapsulated in sodium alginate. Somatic embryo viability was retained, but germination occurred at a reduced frequency compared with the equivalent zygotic embryos. The addition of 0.5% (w/v) activated charcoal to the alginate capsule significantly enhanced root development and germination for somatic embryos but not for zygotic embryos. The possibility of developing an artiflcal endosperm was also investigated, by addition of Litvay (Litvay et al. 1981) nutrients with or without 90 mM sucrose to the alginate-charcoal capsule. This treatment significantly enhanced root development for all embryo categories with the exception of black spruce somatic embryos. Encapsulated and non-encapsulated somatic embryos survived one month cold storage at 4 °C without reduction in germination frequency.
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bioreactor culture of Picea mariana mill black spruce and the species complex Picea glauca engelmannii interior spruce somatic embryos growth parameters
Applied Microbiology and Biotechnology, 1992Co-Authors: T E Tautorus, Monika M Lulsdorf, Susan I Kikcio, David I DunstanAbstract:Somatic embryo cultures of Picea mariana and the species complex P. glauca-engelmannii were each grown in 7.5-l-capacity mechanically-stirred bioreactors containing 61 medium (LP, von Arnold and Eriksson) with 30 mm sucrose. Growth of both species occurred with no observable signs of shear stress due to mechanical agitation. Growth kinetics were analysed using an array of parameters (settled culture volume, packed culture volume, osmolarity, conductivity, pH). These were compared with fresh weight, dry weight, and somatic embryo number in order to determine what parameters were highly correlated with growth and embryo number. Increasing the sucrose concentration from 30 mm to 60 mm resulted in an increase in biomass and total number of somatic embryos. For P. mariana a maximum dry weight of 6.3 gl−1 and 3076 embryos ml−1 occurred in LP medium with 60 mm sucrose after 10–12 days of culture. For P. glauca-engelmannii a maximum dry weight of 4.3 gl−1 and 2278 embryos ml−1 occurred in LP medium with 60 mm sucrose after 6–8 days culture. For all sucrose concentrations, fresh weight, dry weight and embryo number were closely correlated with packed culture volume and conductivity for P. mariana, and settled culture volume, packed culture volume and conductivity for P. glauca-engelmannii.
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growth parameters of embryogenic suspension cultures of interior spruce Picea glauca engelmannii complex and black spruce Picea mariana mill
Plant Science, 1992Co-Authors: Monika M Lulsdorf, T E Tautorus, Susan I Kikcio, David I DunstanAbstract:Abstract Enhanced stability of conifer somatic embryo suspensions could improve their utility for mass propagation. For this purpose, growth characteristics of interior spruce ( Picea glauca-engelmannii complex) and black spruce ( Picea mariana Mill.) embryogenic lines in suspension were determined over a 21-day period as well as the characteristics of several other parameters which might be correlated with growth. Maximum growth for both species in terms of dry weight occurred between day 2 and day 8 whereas the number of embryos per ml (4000–6000) peaked on day 10 or later. Settled culture volume, packed culture volume, osmolarity and medium conductivity were closely correlated with growth. However, osmolarity was considered the best non-destructive growth parameter because only microliters of supernatant were required for its determination. Carbohydrate, nitrogen and potassium utilization were also monitored. Neither ammonium, nitrate nor potassium were found to be limiting but carbohydrate supply could be a growth restricting factor.
Monika M Lulsdorf - One of the best experts on this subject based on the ideXlab platform.
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germination of encapsulated embryos of interior spruce Picea glauca engelmannii complex and black spruce Picea mariana mill
Plant Cell Reports, 1993Co-Authors: Monika M Lulsdorf, T E Tautorus, Susan I Kikcio, Terry D Bethune, David I DunstanAbstract:Interior spruce (Picea glauca engelmannii complex) and black spruce (Picea mariana Mill.) cotyledonary somatic embryos were encapsulated in sodium alginate. Somatic embryo viability was retained, but germination occurred at a reduced frequency compared with the equivalent zygotic embryos. The addition of 0.5% (w/v) activated charcoal to the alginate capsule significantly enhanced root development and germination for somatic embryos but not for zygotic embryos. The possibility of developing an artiflcal endosperm was also investigated, by addition of Litvay (Litvay et al. 1981) nutrients with or without 90 mM sucrose to the alginate-charcoal capsule. This treatment significantly enhanced root development for all embryo categories with the exception of black spruce somatic embryos. Encapsulated and non-encapsulated somatic embryos survived one month cold storage at 4 °C without reduction in germination frequency.
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bioreactor culture of Picea mariana mill black spruce and the species complex Picea glauca engelmannii interior spruce somatic embryos growth parameters
Applied Microbiology and Biotechnology, 1992Co-Authors: T E Tautorus, Monika M Lulsdorf, Susan I Kikcio, David I DunstanAbstract:Somatic embryo cultures of Picea mariana and the species complex P. glauca-engelmannii were each grown in 7.5-l-capacity mechanically-stirred bioreactors containing 61 medium (LP, von Arnold and Eriksson) with 30 mm sucrose. Growth of both species occurred with no observable signs of shear stress due to mechanical agitation. Growth kinetics were analysed using an array of parameters (settled culture volume, packed culture volume, osmolarity, conductivity, pH). These were compared with fresh weight, dry weight, and somatic embryo number in order to determine what parameters were highly correlated with growth and embryo number. Increasing the sucrose concentration from 30 mm to 60 mm resulted in an increase in biomass and total number of somatic embryos. For P. mariana a maximum dry weight of 6.3 gl−1 and 3076 embryos ml−1 occurred in LP medium with 60 mm sucrose after 10–12 days of culture. For P. glauca-engelmannii a maximum dry weight of 4.3 gl−1 and 2278 embryos ml−1 occurred in LP medium with 60 mm sucrose after 6–8 days culture. For all sucrose concentrations, fresh weight, dry weight and embryo number were closely correlated with packed culture volume and conductivity for P. mariana, and settled culture volume, packed culture volume and conductivity for P. glauca-engelmannii.
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growth parameters of embryogenic suspension cultures of interior spruce Picea glauca engelmannii complex and black spruce Picea mariana mill
Plant Science, 1992Co-Authors: Monika M Lulsdorf, T E Tautorus, Susan I Kikcio, David I DunstanAbstract:Abstract Enhanced stability of conifer somatic embryo suspensions could improve their utility for mass propagation. For this purpose, growth characteristics of interior spruce ( Picea glauca-engelmannii complex) and black spruce ( Picea mariana Mill.) embryogenic lines in suspension were determined over a 21-day period as well as the characteristics of several other parameters which might be correlated with growth. Maximum growth for both species in terms of dry weight occurred between day 2 and day 8 whereas the number of embryos per ml (4000–6000) peaked on day 10 or later. Settled culture volume, packed culture volume, osmolarity and medium conductivity were closely correlated with growth. However, osmolarity was considered the best non-destructive growth parameter because only microliters of supernatant were required for its determination. Carbohydrate, nitrogen and potassium utilization were also monitored. Neither ammonium, nitrate nor potassium were found to be limiting but carbohydrate supply could be a growth restricting factor.
Jean Bousquet - One of the best experts on this subject based on the ideXlab platform.
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complete chloroplast genome sequence of a black spruce Picea mariana from eastern canada
Microbiology Resource Announcements, 2020Co-Authors: Lauren Coombe, Diana Lin, Rene L Warren, Heather Kirk, Pawan Pandoh, Yongjun Zhao, Richard A Moore, Andrew J Mungall, Carol Ritland, Jean BousquetAbstract:ABSTRACT Here, we present the chloroplast genome sequence of black spruce (Picea mariana), a conifer widely distributed throughout North American boreal forests. This complete and annotated chloroplast sequence is 123,961 bp long and will contribute to future studies on the genetic basis of evolutionary change in spruce and adaptation in conifers.
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factors affecting the accuracy of genomic selection for growth and wood quality traits in an advanced breeding population of black spruce Picea mariana
BMC Genomics, 2017Co-Authors: Jean Beaulieu, Patrick R N Lenz, Shawn D Mansfield, Sebastien Clement, Mireille Desponts, Jean BousquetAbstract:Genomic selection (GS) uses information from genomic signatures consisting of thousands of genetic markers to predict complex traits. As such, GS represents a promising approach to accelerate tree breeding, which is especially relevant for the genetic improvement of boreal conifers characterized by long breeding cycles. In the present study, we tested GS in an advanced-breeding population of the boreal black spruce (Picea mariana [Mill.] BSP) for growth and wood quality traits, and concurrently examined factors affecting GS model accuracy. The study relied on 734 25-year-old trees belonging to 34 full-sib families derived from 27 parents and that were established on two contrasting sites. Genomic profiles were obtained from 4993 Single Nucleotide Polymorphisms (SNPs) representative of as many gene loci distributed among the 12 linkage groups common to spruce. GS models were obtained for four growth and wood traits. Validation using independent sets of trees showed that GS model accuracy was high, related to trait heritability and equivalent to that of conventional pedigree-based models. In forward selection, gains per unit of time were three times higher with the GS approach than with conventional selection. In addition, models were also accurate across sites, indicating little genotype-by-environment interaction in the area investigated. Using information from half-sibs instead of full-sibs led to a significant reduction in model accuracy, indicating that the inclusion of relatedness in the model contributed to its higher accuracies. About 500 to 1000 markers were sufficient to obtain GS model accuracy almost equivalent to that obtained with all markers, whether they were well spread across the genome or from a single linkage group, further confirming the implication of relatedness and potential long-range linkage disequilibrium (LD) in the high accuracy estimates obtained. Only slightly higher model accuracy was obtained when using marker subsets that were identified to carry large effects, indicating a minor role for short-range LD in this population. This study supports the integration of GS models in advanced-generation tree breeding programs, given that high genomic prediction accuracy was obtained with a relatively small number of markers due to high relatedness and family structure in the population. In boreal spruce breeding programs and similar ones with long breeding cycles, much larger gain per unit of time can be obtained from genomic selection at an early age than by the conventional approach. GS thus appears highly profitable, especially in the context of forward selection in species which are amenable to mass vegetative propagation of selected stock, such as spruces.
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development of highly reliable in silico snp resource and genotyping assay from exome capture and sequencing an example from black spruce Picea mariana
Molecular Ecology Resources, 2016Co-Authors: Nathalie Pavy, Astrid Deschenes, Brian Boyle, Jean Beaulieu, Jean BousquetAbstract:Picea mariana is a widely distributed boreal conifer across Canada and the subject of advanced breeding programmes for which population genomics and genomic selection approaches are being developed. Targeted sequencing was achieved after capturing P. mariana exome with probes designed from the sequenced transcriptome of Picea glauca, a distant relative. A high capture efficiency of 75.9% was reached although spruce has a complex and large genome including gene sequences interspersed by some long introns. The results confirmed the relevance of using probes from congeneric species to perform successfully interspecific exome capture in the genus Picea. A bioinformatics pipeline was developed including stringent criteria that helped detect a set of 97,075 highly reliable in silico SNPs. These SNPs were distributed across 14,909 genes. Part of an Infinium iSelect array was used to estimate the rate of true positives by validating 4267 of the predicted in silico SNPs by genotyping trees from P. mariana populations. The true positive rate was 96.2% for in silico SNPs, compared to a genotyping success rate of 96.7% for a set 1115 P. mariana control SNPs recycled from previous genotyping arrays. These results indicate the high success rate of the genotyping array and the relevance of the selection criteria used to delineate the new P. mariana in silico SNP resource. Furthermore, in silico SNPs were generally of medium to high frequency in natural populations, thus providing high informative value for future population genomics applications.
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transition from juvenile to mature wood in black spruce Picea mariana mill b s p
Wood and Fiber Science, 2005Co-Authors: Ahmed Koubaa, Nathalie Isabel, Jean BousquetAbstract:The radial patterns of several intra-ring traits in increment cores of black spruce (Picea mariana (Mill.) B.S.P.) plantation trees were modeled with polynomials to characterize their trends and to estimate the transition age from juvenile to mature wood. Wood density, ring width, latewood density, and latewood proportion were obtained by X-ray densitometry. Average radial trends were similar to those reported earlier in Picea species. For all traits measured, significant differences were found among diameter classes. Thus, the juvenile wood production period varies with growth rate. In addition, transition age for a given diameter class varies, depending on trait. Hence, transition age needs to be defined more precisely, basing it on biological processes.
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variation in mitochondrial dna reveals multiple distant glacial refugia in black spruce Picea mariana a transcontinental north american conifer
Molecular Ecology, 2004Co-Authors: Juan P Jaramillocorrea, Jean Beaulieu, Jean BousquetAbstract:Range-wide genetic variation of black spruce (Picea mariana) was studied using polymerase chain reaction-random fragment length polymorphism markers of the mitochondrial genome. Four polymorphic mitochondrial DNA (mtDNA) loci were surveyed and two or three alleles were detected at each locus, resulting in 10 multilocus mtDNA types or mitotypes. A significant subdivision of population genetic diversity was detected (GST = 0.671; NST = 0.726), suggesting low levels of gene flow among populations. The distribution of mitotypes was not random (NST > GST; P < 0.05) and revealed four partially overlapping zones, presumably representative of different glacial populations. Comparison of the genetic structure derived from mtDNA markers and the colonization paths previously deduced from the fossil and pollen records allow us to infer at least three southern and one northeastern glacial populations for black spruce. The patterns revealed in this study suggest that black spruce shares its biogeographical history with other forest-associated North American species.
T E Tautorus - One of the best experts on this subject based on the ideXlab platform.
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germination of encapsulated embryos of interior spruce Picea glauca engelmannii complex and black spruce Picea mariana mill
Plant Cell Reports, 1993Co-Authors: Monika M Lulsdorf, T E Tautorus, Susan I Kikcio, Terry D Bethune, David I DunstanAbstract:Interior spruce (Picea glauca engelmannii complex) and black spruce (Picea mariana Mill.) cotyledonary somatic embryos were encapsulated in sodium alginate. Somatic embryo viability was retained, but germination occurred at a reduced frequency compared with the equivalent zygotic embryos. The addition of 0.5% (w/v) activated charcoal to the alginate capsule significantly enhanced root development and germination for somatic embryos but not for zygotic embryos. The possibility of developing an artiflcal endosperm was also investigated, by addition of Litvay (Litvay et al. 1981) nutrients with or without 90 mM sucrose to the alginate-charcoal capsule. This treatment significantly enhanced root development for all embryo categories with the exception of black spruce somatic embryos. Encapsulated and non-encapsulated somatic embryos survived one month cold storage at 4 °C without reduction in germination frequency.
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bioreactor culture of Picea mariana mill black spruce and the species complex Picea glauca engelmannii interior spruce somatic embryos growth parameters
Applied Microbiology and Biotechnology, 1992Co-Authors: T E Tautorus, Monika M Lulsdorf, Susan I Kikcio, David I DunstanAbstract:Somatic embryo cultures of Picea mariana and the species complex P. glauca-engelmannii were each grown in 7.5-l-capacity mechanically-stirred bioreactors containing 61 medium (LP, von Arnold and Eriksson) with 30 mm sucrose. Growth of both species occurred with no observable signs of shear stress due to mechanical agitation. Growth kinetics were analysed using an array of parameters (settled culture volume, packed culture volume, osmolarity, conductivity, pH). These were compared with fresh weight, dry weight, and somatic embryo number in order to determine what parameters were highly correlated with growth and embryo number. Increasing the sucrose concentration from 30 mm to 60 mm resulted in an increase in biomass and total number of somatic embryos. For P. mariana a maximum dry weight of 6.3 gl−1 and 3076 embryos ml−1 occurred in LP medium with 60 mm sucrose after 10–12 days of culture. For P. glauca-engelmannii a maximum dry weight of 4.3 gl−1 and 2278 embryos ml−1 occurred in LP medium with 60 mm sucrose after 6–8 days culture. For all sucrose concentrations, fresh weight, dry weight and embryo number were closely correlated with packed culture volume and conductivity for P. mariana, and settled culture volume, packed culture volume and conductivity for P. glauca-engelmannii.
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growth parameters of embryogenic suspension cultures of interior spruce Picea glauca engelmannii complex and black spruce Picea mariana mill
Plant Science, 1992Co-Authors: Monika M Lulsdorf, T E Tautorus, Susan I Kikcio, David I DunstanAbstract:Abstract Enhanced stability of conifer somatic embryo suspensions could improve their utility for mass propagation. For this purpose, growth characteristics of interior spruce ( Picea glauca-engelmannii complex) and black spruce ( Picea mariana Mill.) embryogenic lines in suspension were determined over a 21-day period as well as the characteristics of several other parameters which might be correlated with growth. Maximum growth for both species in terms of dry weight occurred between day 2 and day 8 whereas the number of embryos per ml (4000–6000) peaked on day 10 or later. Settled culture volume, packed culture volume, osmolarity and medium conductivity were closely correlated with growth. However, osmolarity was considered the best non-destructive growth parameter because only microliters of supernatant were required for its determination. Carbohydrate, nitrogen and potassium utilization were also monitored. Neither ammonium, nitrate nor potassium were found to be limiting but carbohydrate supply could be a growth restricting factor.
Nathalie Isabel - One of the best experts on this subject based on the ideXlab platform.
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enhancing genetic mapping of complex genomes through the design of highly multiplexed snp arrays application to the large and unsequenced genomes of white spruce and black spruce
BMC Genomics, 2008Co-Authors: Nathalie Pavy, Nathalie Isabel, Manuel Lamothe, Betty Pelgas, Stephanie Beauseigle, Sylvie Blais, Isabelle GosselinAbstract:Background To explore the potential value of high-throughput genotyping assays in the analysis of large and complex genomes, we designed two highly multiplexed Illumina bead arrays using the GoldenGate SNP assay for gene mapping in white spruce (Picea glauca [Moench] Voss) and black spruce (Picea mariana [Mill.] B.S.P.).
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transition from juvenile to mature wood in black spruce Picea mariana mill b s p
Wood and Fiber Science, 2005Co-Authors: Ahmed Koubaa, Nathalie Isabel, Jean BousquetAbstract:The radial patterns of several intra-ring traits in increment cores of black spruce (Picea mariana (Mill.) B.S.P.) plantation trees were modeled with polynomials to characterize their trends and to estimate the transition age from juvenile to mature wood. Wood density, ring width, latewood density, and latewood proportion were obtained by X-ray densitometry. Average radial trends were similar to those reported earlier in Picea species. For all traits measured, significant differences were found among diameter classes. Thus, the juvenile wood production period varies with growth rate. In addition, transition age for a given diameter class varies, depending on trait. Hence, transition age needs to be defined more precisely, basing it on biological processes.
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rapds as an aid to evaluate the genetic integrity of somatic embryogenesis derived populations of Picea mariana mill b s p
Theoretical and Applied Genetics, 1993Co-Authors: Nathalie Isabel, L Tremblay, M Michaud, Francine Tremblay, Jean BousquetAbstract:The usefulness of random amplified polymorphic DNA (RAPD) in assessing the genetic stability of somatic embryogenesis-derived populations of black spruce [Picea mariana (Mill.) B.S.P.] was evaluated. Three arbitrary 11-mer primers were successfully used to amplify DNA from both in-vivo and in-vitro material. Twenty-five embryogenic cell lines, additional zygotic embryos and megagametophytes from three controlled crosses involving four selected genotypes of black spruce were used for the segregation analysis of RAPD variants. Ten markers were genetically characterized and used to evaluate the genetic stability of somatic embryos derived from three embryogenic cell lines (one cell line per cross, 30 somatic embryos per cell line). No variation was detected within clones. The utilization of RAPD markers both for the assessment of genetic stability of clonal materials and to certify genetic stability throughout the process of somatic embryogenesis is discussed.