Variation in growth rate within and among full-sib families of Douglas-fir (Pseudotsuga menziesii)

1989 ◽  
Vol 67 (1) ◽  
pp. 140-145 ◽  
Author(s):  
Jack Maze ◽  
Satindranath Banerjee ◽  
Yousry A. El-Kassaby
Keyword(s):  
Growth Rate ◽  
Pseudotsuga Menziesii ◽  
Common Garden ◽  
Developmental Models ◽  
Genetic Complexity ◽  
Group Variation ◽  
Sib Families ◽  
Lateral Branches ◽  
Natural Situation ◽  
Intraspecific Group

Variation in growth rate in the four uppermost lateral branches of seedlings of Pseudotsuga menziesii (Mirb.) Franco was greatest among individuals within full-sib families. These results are consistent with those from other studies on conifers indicating there is much more within- than among-intraspecific group variation. Since these seedlings were grown in a common garden, it is assumed that the among-individual variation has a genetic basis. The greatest growth rate was in seedlings produced by crossing trees that had the highest average increments of growth; the lowest growth rate was in seedlings produced by crossing trees that had the lowest average increments of growth. However, the seedlings with the lowest growth rate were similar to those produced by crosses between trees with high average increments of growth. This implies that phenotypically superior trees, as assessed in a natural situation, do not necessarily produce superior offspring in their second year of growth. The high within-family variation coupled with the ontogenetic events associated with growth rate implies a complex multigenic control of growth rate. The genetic complexity of an apparently simple developmental event such as growth in length implies that evolutionary or developmental models based on a small portion of the genome may be inadequate.

A comparison of variation of Pseudotsuga menziesii seedlings from genetically defined and undefined sources

1989 ◽  
Vol 67 (3) ◽  
pp. 945-947 ◽  
Author(s):  
Jack Maze ◽  
Satindranath Banerjee
Keyword(s):  
Pseudotsuga Menziesii ◽  
Genetic Background ◽  
Complex Mixture ◽  
Growing Season ◽  
Population Variation ◽  
Mixed Genetic Background ◽  
Diverse Background ◽  
Group Variation ◽  
Sib Families

Leader lengths were compared for seedlings (i) from full-sib families and (ii) of mixed genetic background 12 times over their second growing season. We wished to examine whether the variation in genetically defined groups was equal to, or less than, that from a genetically diverse background. Aside from one time, there was no difference in within-group variation for full-sib seedlings and for those of mixed genetic background. When variation was not equal, it was one of the full-sib families that was the most variable. This indicates that the high within-population variation in Pseudotsuga menziesii reflects crossing between highly variable individuals and not a complex mixture of half-sib families.

scholarly journals Feed demand behavior in sea bass juveniles: Effects on individual specific growth rate variation and health (inter-individual and inter-group variation)

Aquaculture ◽  
2008 ◽  
Vol 274 (1) ◽  
pp. 87-95 ◽  
Author(s):  
S. Millot ◽  
M.-L. Bégout ◽  
J. Person-Le Ruyet ◽  
G. Breuil ◽  
C. Di-Poï ◽  
...  
Keyword(s):  
Growth Rate ◽  
Specific Growth Rate ◽  
Specific Growth ◽  
Sea Bass ◽  
Rate Variation ◽  
Group Variation

ASSOCIATIONS BETWEEN ALLOZYME GENOTYPES AND QUANTITATIVE TRAITS IN DOUGLAS-FIR [PSEUDOTSUGA MENZIESII (MIRB.) FRANCO]

Genetics ◽  
1982 ◽  
Vol 101 (1) ◽  
pp. 103-115
Author(s):  
Yousry A El-Kassaby
Keyword(s):  
Pseudotsuga Menziesii ◽  
Discriminant Function ◽  
Discriminant Function Analysis ◽  
Quantitative Traits ◽  
Function Analysis ◽  
Genotypic Differences ◽  
Enzyme Loci ◽  
Canonical Variates ◽  
Sib Families ◽  
Highly Correlated

ABSTRACT Effects of maternal genotypes for eight enzyme loci on seven quantitative traits in 41 half-sib families were determined. Heritability estimates for the quantitative traits were highly significant and ranged from 0.57 to 0.86. Only six of 112 comparisons (56 comparisons for each of the genotypes and 56 for homozygous versus heterozygous contrasts) were statistically significant (P < 0.05). None of these significant comparisons could be associated with either a particular allele or a particular genotype. No heterotic effects were observed when the homozygous genotypes were compared with the heterozygous ones. Because the quantitative traits are highly correlated, a discriminant function analysis was performed to obtain the two most important canonical variates that accounted for 75% of the variance in the quantitative traits. There were no significant associations among enzyme loci and the two canonical variates. I conclude that, in this study, enzyme genotypic differences do not influence the quantitative traits to a major extent.

Genetic Variation in Chamaecyparis nootkatensis from Coastal British Columbia1

1992 ◽  
Vol 7 (1) ◽  
pp. 25-29 ◽  
Author(s):  
M. L. Cherry ◽  
D. T. Lester
Keyword(s):  
Genetic Variation ◽  
Growth Traits ◽  
Weight Ratio ◽  
Common Garden ◽  
Dry Weight ◽  
Frost Damage ◽  
Chamaecyparis Nootkatensis ◽  
Shoot Dry Weight ◽  
Lateral Branches ◽  
Port Orford Cedar

Abstract Genetic variation in several traits of Alaska-cedar (Chamaecyparis nootkatensis) was measured in progeny from seven coastal B.C. provenances, each represented by three open-pollinated families. The common-garden nursery trial also included one provenance of Port-Orford cedar (Chamaecyparis lawsoniana). Growth traits and frost hardiness were measured at the end of the first growing season, and morphological traits after the second year. Provenances varied in percentage germination, shoot dry weight, shoot to root dry weight ratio, number of lateral branches per stem, and cold injury to a minimum temperature of -20°C in December. Families differed in height, root collar diameter, and in the number of nodes of primary foliage. Port-Orford cedar exhibited much greater height, stem caliper, and dry weight than any Alaska-cedar provenance, but was more susceptible to frost damage. West. J. Appl. For. 7(1):25-29.

Comparison of genetic and phenotypic parameters in a purebred and a synthetic beef cattle population

1991 ◽  
Vol 71 (2) ◽  
pp. 279-285 ◽  
Author(s):  
M. F. Liu ◽  
M. Makarechian ◽  
R. T. Berg
Keyword(s):  
Growth Rate ◽  
Birth Weight ◽  
Beef Cattle ◽  
Variance Components ◽  
Growth Traits ◽  
Cattle Population ◽  
Coefficients Of Variation ◽  
Sib Families ◽  
Phenotypic Variations ◽  
Two Populations

Genetic and phenotypic parameters of growth traits from birth to 1 year of age were compared in a multibreed Beef Synthetic (SY) and a purebred Hereford (HE) population managed together under the same environmental conditions and selected for growth rate from 1961 to 1979. Growth traits studied were birth weight, preweaning and postweaning gains. Records of 2077 calves of 70 HE and 100 SY paternal half-sib families were used for analysis. Except for birth weight, phenotypic variances of growth traits were similar for the synthetic (SY) and purebred (HE) populations, but genetic variances were larger in SY than in HE for all growth traits except postweaning gain in males. The coefficients of variation were comparable for all the traits studied in the two populations, indicating that phenotypic variations in the multibreed population and the purebred population were similar. Key words: Variance components, heritability, beef cattle

Increased population growth rate in invasive polyploidCentaurea stoebein a common garden

2012 ◽  
Vol 15 (9) ◽  
pp. 947-954 ◽  
Author(s):  
Min A. Hahn ◽  
Yvonne M. Buckley ◽  
Heinz Müller-Schärer
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Population Growth Rate ◽  
Common Garden

scholarly journals Looking for the needle in a downsized haystack: Whole-exome sequencing unravels how selection and gene flow have shaped climatic adaptation in Douglas-fir (Pseudotsuga menziesii)

2020 ◽  
Author(s):  
Jan-Peter George ◽  
Silvio Schueler ◽  
Michael Grabner ◽  
Sandra Karanitsch-Ackerl ◽  
Konrad Mayer ◽  
...  
Keyword(s):  
Gene Flow ◽  
Pseudotsuga Menziesii ◽  
Multiple Testing ◽  
Common Garden ◽  
Douglas Fir ◽  
Exome Capture ◽  
Nucleotide Polymorphisms ◽  
Local Climate ◽  
Climate Conditions ◽  
Climatic Adaptation

AbstractThe widespread Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) occurs along a steep gradient of diverse climates throughout its natural range, which is expected to result in spatially varying selection to local climate conditions. However, phenotypic signals of climatic adaptation can often be confounded, because unraveled clines covary with signals caused by neutral evolutionary processes such as gene flow and genetic drift. Here, we present phenotypic and genotypic data from a common garden experiment showing a putative signal of adaptation to climate after trees have been growing for 40 years in a common environment. Sixteen Douglas-fir provenances originating from a North-to-South gradient of approx. 1,000 km were analyzed and genomic information was obtained from exome capture, which resulted in an initial genomic dataset of >90,000 single nucleotide polymorphisms. We used a restrictive and conservative filtering approach which permitted us to include only SNPs and individuals in environmental association analysis (EAA) that were free of potentially confounding effects (LD, relatedness among trees, heterozygosity deficiency and deviations from Hardy-Weinberg proportions). We used four conceptually different genome scan methods based on FST outlier detection and gene-environment association in order to disentangle truly adaptive SNPs from neutral SNPs and found that a relatively small proportion of the exome showed a truely adaptive signal (0.01-0.17%) when population substructuring and multiple testing was accounted for. Nevertheless, the unraveled SNP candidates showed significant relationship with climate at provenance origins which strongly suggests that they have most likely featured adaption in Douglas-fir across a steep climatic gradient. Two SNPs were independently found by three of the employed algorithms and one could be assigned with high probability to a Picea abies homolog gene involved in circadian clock control as was also found in Populus balsamifera.

scholarly journals Testing the link between genome size and growth rate in maize

2016 ◽  
Author(s):  
Maud I Tenaillon ◽  
Domenica Manicacci ◽  
Stéphane D Nicolas ◽  
Francois Tardieu ◽  
Claude Welcker
Keyword(s):  
Growth Rate ◽  
Genome Size ◽  
Inbred Lines ◽  
Genetic Structuring ◽  
Climate Conditions ◽  
Genetic Groups ◽  
Rate Maximum ◽  
Group Variation ◽  
Open Question ◽  
Modern Breeding

Little is known about the factors driving within species Genome Size (GS) variation. GS may be shaped indirectly by natural selection on development and adaptative traits. Because GS variation is particularly pronounced in maize, we have sampled 83 maize inbred lines from three well described genetic groups adapted to contrasted climate conditions: inbreds of tropical origin , Flint inbreds grown in temperate climates, and Dent inbreds distributed in the Corn Belt. As a proxy for growth rate, we measured the Leaf Elongation Rate maximum during nighttime (LERmax) as well as GS in all inbred lines. In addition we combined available and new nucleotide polymorphism data at 29,090 sites to characterize the genetic structure of our panel. We found significant variation for both LERmax and GS among groups defined by our genetic structuring. Tropicals displayed larger GS than Flints while Dents exhibited intermediate values. LERmax followed the opposite trend with greater growth rate in Flints than in Tropicals. In other words, LERmax and GS exhibited a significantly negative correlation (r=-0.27). However, this correlation was driven by among-group variation rather than within-group variation – it was no longer significant after controlling for structure and kinship among inbreds. Our results indicate that selection on GS may have accompanied ancient maize diffusion from its center of origin, with large DNA content excluded from temperate areas. Whether GS has been targeted by more intense selection during modern breeding within groups remains an open question. <!--[if !supportLineBreakNewLine]--> <!--[endif]-->

Multivariate variation within and between open-pollinated families of Douglas-fir (Pseudotsuga menziesii)

1987 ◽  
Vol 65 (8) ◽  
pp. 1614-1621 ◽  
Author(s):  
R. K. Scagel ◽  
Y. A. El-Kassaby ◽  
J. Maze
Keyword(s):  
Pseudotsuga Menziesii ◽  
Common Garden ◽  
Morphological Data ◽  
Common Garden Experiment ◽  
Single Population ◽  
Causal Factors ◽  
Historical Factors ◽  
Sources Of Variation ◽  
Family Variable ◽  
Family Variation

The morphological variation of seedlings from a single population of Pseudotsuga menziesii was examined and related to their maternal parentage (41 families) and speed of germination (selection) during the course of a common garden experiment. The largest source of variation among seedlings was attributed to within-family variation. Furthermore, within-family variable intercorrelations differed from family to family, suggesting that intrinsic causal factors are important to the generation and organization of variation. Pooled within-family variation was explored and shown to be related to the between-family variation. These results suggest that developmental and historical factors cannot be ignored in the interpretation and exploitation of sources of variation. Such considerations identify limitations to Neo-Darwinian explanations and suggest reappraisal of progeny trials with respect to these issues. The results also pose limitations to our interpretations of genetic similarity on the basis of multivariate morphological data.

scholarly journals Shifting thresholds: rapid evolution of migratory life histories in steelhead/rainbow trout, Oncorhynchus mykiss

2014 ◽  
Author(s):  
Corey Phillis ◽  
Jonathan W Moore ◽  
Mathieu Buoro ◽  
Sean Hayes ◽  
Carlos Garza ◽  
...  
Keyword(s):  
Growth Rate ◽  
Oncorhynchus Mykiss ◽  
Life Histories ◽  
Rapid Evolution ◽  
Common Garden ◽  
Source Population ◽  
Contemporary Evolution ◽  
Conditional Strategy ◽  
Threshold Size ◽  
Rainbow Trout Oncorhynchus Mykiss

Expression of phenotypic plasticity depends on reaction norms adapted to historic selective regimes; anthropogenic changes in these selection regimes necessitate contemporary evolution or extirpation. Adaptation of conditional strategies following a change in the selection regime requires evolution of either the environmentally influenced cue (e.g. growth rate) or the state (e.g. size threshold) at which an individual switches between conditional strategies. Using a population of steelhead (Oncorhynchus mykiss) introduced above a barrier waterfall in 1910, we evaluate how the conditional strategy to migrate evolves in response to selection against migration. Common garden-raised offspring of parents from the above-barrier population were 11% smaller and 31% lighter than offspring of parents from the below-barrier source population. Using a novel analytical approach we estimate that the mean size at which above-barrier fish switch between the resident and migrant strategy is 43% larger than below-barrier fish. As a result, above-barrier fish were 30% less likely to express the migratory strategy. Our results demonstrate how rapid and opposing changes in growth rate and threshold size contribute to the contemporary evolution of a conditional strategy and indicate that migratory barriers may elicit rapid evolution towards the resident life-history on timescales relevant for conservation and management of conditionally migratory species.

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