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Duncan, Canada

Funda T.,University of British Columbia | Funda T.,Czech University of Life Sciences | Liewlaksaneeyanawin C.,University of British Columbia | Fundova I.,University of British Columbia | And 7 more authors.
Canadian Journal of Forest Research | Year: 2011

Seed orchards' parental reproductive success is often assessed through surveys of seed-and pollen-cone production (reproductive investment). Although the reliability of this approach has been questioned, its speed and ease made it the method of choice for providing approximate estimates for the genetic quality and quantity of seed orchard crops. In this study, reproductive investment data from various female and male phenotypic assessment methods from three seed orchards (lodgepole pine (Pinus contorta Dougl. ex. Loud. var. latifolia Engelm.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and western larch (Larix occidentalis Nutt.)) were compared with reproductive success estimates based on DNA fingerprinting and parentage analyses. The use of reproductive investment as a proxy to reproductive success on estimating seed crop's volume genetic worth and diversity (measured by effective number of parents) was evaluated. Regression analyses indicated that the phenotypic assessment methods reflect the true parental reproductive success and that estimates of seed-and pollen-cone volume production appear to be the most appropriate indicators of female and male reproductive success, respectively. Although the best combination of female-male survey methods produced inflated effective number of parents estimates, the genetic worth estimates were similar to those based on DNA, highlighting their robustness to fertility variation assessment. Source


Lai B.S.,University of British Columbia | Funda T.,University of British Columbia | Funda T.,Czech University of Life Sciences | Liewlaksaneeyanawin C.,University of British Columbia | And 7 more authors.
Annals of Forest Science | Year: 2010

Pollination dynamics was studied in a Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seed orchard using 8 nuclear microsatellite markers and pedigree reconstruction. The seed orchard consisted of 49 parents (clones). Cone-crop management included bloom delay and supplemental mass pollination (SMP) using 12 internal and 4 external pollen donors. A random sample of 801 bulk seeds was genotyped for both haploid megagametophyte and corresponding diploid embryo. Using the parental population's multilocus genotypes, full pedigree reconstruction generated all the information needed to estimate the maternal, paternal, and parental reproductive success, selfing, pollen contamination, and pollination success of the 4 external pollen donors. Maternal, paternal, and parental reproductive success varied with 80% of gametes being produced by 23, 45, and 37% of the orchard's parents, respectively, resulting in a drastically reduced effective population size as compared to the census number (14 vs. 53). Selfing, pollen contamination, and aggregate SMP success (internal and external) were estimated to be 15.2, 10.4, and 15.0%, respectively. Full pedigree reconstruction was effective in unraveling the orchard's pollination dynamics and both female and male reproductive success. © 2010 INRA, EDP Sciences. Source


Kong L.,University of Victoria | Kong L.,University of Georgia | von Aderkas P.,University of Victoria | Zaharia I.,National Research Council Canada | And 3 more authors.
Journal of Plant Growth Regulation | Year: 2012

In lodgepole pine (Pinus contorta Dougl. ex Loud. var. latifolia Engelm), cone initiation and gender differentiation are site-specific in long-shoot buds, with female cones in the distal portion and male cones in the proximal portion. By using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) in multiple-reaction monitoring (MRM) mode, cytokinins, indole-3-acetic acid (IAA), abscisic acid (ABA), and their selected metabolites were investigated in developing long-shoot buds from multiple genotypes. Spatially, higher concentrations of trans-zeatin riboside (t-ZR) and dihydrozeatin riboside (dhZR) existed in the distal parts of long-shoot buds, whereas concentrations of isopentenyl adenosine (iPA), IAA, ABA glucose ester (ABA-GE), and phaseic acid (PA) were higher in the proximal parts in all investigated genotypes. In long-shoot buds of genotypes with a history of high female cone yield, concentrations of t-ZR and the ratio of zeatin-type to isopentenyl-type cytokinins were higher in the entire buds, whereas dhZR or IAA was higher in either the distal or the proximal part, respectively. In low female cone yielding genotypes, concentrations of c-ZR, iPA, ABA-GE, and PA were higher in both of the parts. Temporally, concentrations of several hormone-related compounds showed obvious changes in late June and late July, prior to male and female cone bud differentiation. This study reveals that the local hormonal status in a long-shoot bud at specific developmental stages may play an important role in gender determination and cone yield. © 2012 Springer Science+Business Media, LLC. Source


Kong L.,University of Victoria | Kong L.,University of Georgia | von Aderkas P.,University of Victoria | Owen S.J.,National Research Council Canada | And 3 more authors.
New Forests | Year: 2012

Stem-girdling treatments were applied in early spring to stimulate cone formation in two genotypes of interior Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco). After girdling treatments, male cone yield increased significantly in the next growing season. The increase was 14-fold in genotype 9137. In genotype 9550, more than 8,700 male cones were induced from each tree whereas no male cones were found in controls. Female cone yield was zero in controls and low for girdled trees in both genotypes. Multiple phytohormone-related compounds, including gibberellins (GAs), cytokinins, indole-3-acetic acid (IAA), abscisic acid (ABA) and their selected metabolites, were analyzed in developing long shoots after girdling treatments by high performance liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) in multiple reaction monitoring mode. Concentrations of GA 4 were slightly higher at week 2 following girdling treatment, whereas at week 8 lower GA 4 concentrations were found in girdled samples. Stem girdling did not affect concentrations of IAA and major cytokinins, such as zeatin riboside and isopentenyl adenosine. Concentrations of ABA differed two-fold between the genotypes. Although girdling treatment did not cause differences in ABA concentrations, it generally resulted in higher concentrations of ABA glucose ester. Concentration increase of 7′-hydroxy ABA by girdling was only found in genotype 9550 at week 8. Girdling caused little change in concentrations of phaseic acid in both genotypes. © 2011 Springer Science+Business Media B.V. Source


Stoehr M.,British Columbia Ministry of forests | Ott P.,British Columbia Ministry of forests | Woods J.,SelectSeed Company Ltd
Annals of Forest Science | Year: 2015

Context: The effects of inbreeding on growth traits have been studied and are fairly well understood in young conifers. However, in trees approaching mid-rotation, this information is not widely available at present.Aim: The aim of this study is to assess inbreeding depression in mid-rotation coastal Douglas-fir in growth traits, survival, and wood density.Methods: Several levels of inbreeding were created in coastal Douglas-fir, using a nine-clone founder population to produce 148 families with varying levels of inbreeding ranging from f = 0 (outcrossed) to f = 0.5 (selfed). The trees were planted in 1987 on two farm-field sites in coastal BC. Here, we report effects of inbreeding in height, diameter, tree volume, survival, and wood density in 26-year-old trees.Results: Previous results obtained from this test population showed negative near linear effects with levels of inbreeding in seed production, nursery growth performance, and growth traits in the field assessed at age 10. At age 26, inbreeding depression was highest in survival, ranging from 20 to 80 % for f = 0.125 and f = 0.5, respectively. In contrast, the most severe inbreeding depression among the three levels of inbreeding was only 4 % for wood density at f = 0.5 (selfing). Inbreeding depression in height, diameter at breast height (dbh), and volume increased linearly from f = 0 to f = 0.25, then leveled off.Conclusion: Founder genotypes had varied responses to inbreeding as parental breeding values across inbreeding levels were inconsistent (in magnitude, sign, and trait). No differences in levels of inbreeding depression were found between full-sib matings and parent-offspring matings. These findings have implications for the testing of parents within sublines, where inbreeding is accumulated in sublines. However, since parents respond differently to levels of inbreeding, their performance may not be well correlated to their quality as outcrossing parents. © 2014, INRA and Springer-Verlag France. Source

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