A model of genetic variation for Pinus ponderosa in the Inland Northwest (U.S.A.): applications in gene resource management

1991 ◽  
Vol 21 (10) ◽  
pp. 1491-1500 ◽  
Author(s):  
G. E. Rehfeldt
Keyword(s):  
Genetic Variation ◽  
Pinus Ponderosa ◽  
Regression Models ◽  
Common Garden ◽  
Shoot Elongation ◽  
The United States ◽  
Independent Data ◽  
Gene Conservation ◽  
Seed Transfer ◽  
Inland Northwest

Models were developed to describe genetic variation among 201 seedling populations ofPinusponderosa var. ponderosa in the Inland Northwest of the United States. Common-garden studies provided three variables that reflected growth and development in field environments and three principal components of six variables that reflected patterns of shoot elongation. Regression models were developed for describing genetic variation across the landscape. Using functions of latitude, longitude, and elevation as descriptors, these models produced values of R2 that were as large as 0.66, while averaging 0.39. The models described genetic variation as occurring along relatively steep elevational clines and gentle geographic (i.e., latitudinal and longitudinal) clines. An exercise at validating the models with independent data supported their veracity. Predictions made by the models are applied to limiting seed transfer, designing breeding zones, planning gene conservation programs, interpreting phenotypic variation, and predicting the effects of environmental change on the adaptedness of populations.

scholarly journals Genetic variation of piperidine alkaloids in Pinus ponderosa: a common garden study

2008 ◽  
Vol 103 (3) ◽  
pp. 447-457 ◽  
Author(s):  
Elizabeth A. Gerson ◽  
Rick G. Kelsey ◽  
J. Bradley St Clair
Keyword(s):  
Genetic Variation ◽  
Pinus Ponderosa ◽  
Common Garden ◽  
Piperidine Alkaloids

Genecology and seed zones for tapertip onion in the US Great Basin

Botany ◽  
2013 ◽  
Vol 91 (10) ◽  
pp. 686-694 ◽  
Author(s):  
R.C. Johnson ◽  
Barbara C. Hellier ◽  
Ken W. Vance-Borland
Keyword(s):  
Great Basin ◽  
Plant Traits ◽  
Principal Component ◽  
Common Garden ◽  
The United States ◽  
Production Traits ◽  
Seed Transfer ◽  
Common Gardens ◽  
Seed Zones ◽  
Surrounding Areas

The choice of germplasm is critical for sustainable restoration, yet seed transfer guidelines are lacking for all but a few herbaceous species. Seed transfer zones based on genetic variability and climate were developed using tapertip onion (Allium acuminatum Hook.) collected in the Great Basin and surrounding areas in the United States. Bulbs from 53 locations were established at two common garden sites and morphological (such as leaf and scape dimensions), phenological (such as bolting date and flowering), and production traits (such as emergence and seeds per plant) were measured. Differences among source locations for plant traits within both common gardens were strong (P < 0.001), indicating genetic variation. Principal component 1 (PC 1) for phenological traits, with R2 = 0.59, and PC 1 for production traits, with R2 = 0.65, were consistently correlated with annual, maximum, minimum, and average temperature, annual precipitation, and frost-free days at source locations (P < 0.05). Regression of PC 1 phenology and PC 1 production scores with source location climates resulted in models with R2 values of 0.73 and 0.52, respectively. Using a geographic information system, maps of these models were overlaid to develop proposed seed zones to guide the choice of germplasm for conservation and restoration of tapertip onion across the collection region.

Ecological genetics of Pinuscontorta in the Wasatch and Uinta Mountains of Utah

1985 ◽  
Vol 15 (3) ◽  
pp. 524-530 ◽  
Author(s):  
G. E. Rehfeldt
Keyword(s):  
Regression Models ◽  
Laboratory Tests ◽  
Cold Hardiness ◽  
Geographic Location ◽  
Shoot Elongation ◽  
Ecological Genetics ◽  
Growth Potential ◽  
Uinta Mountains ◽  
Population Means ◽  
Seed Transfer

Genetic differentiation of 45 populations of Pinuscontorta primarily from the Wasatch and Uinta Mountains was studied in field, greenhouse, and laboratory tests. Analyses of variables reflecting growth potential, morphology, cold hardiness, and periodicity of shoot elongation revealed population differentiation for a variety of traits. Regression models related as much as 77% of the variance among population means to the elevation and geographic location of the seed source. For genetic variation to be arranged along relatively steep environmental clines implies pronounced adaptive differentiation. As a result, seed transfer in reforestation should be restricted severely if maladaptation is to be controlled.

Landscape patterns of phenotypic variation and population structuring in a selfing grass, Elymus glaucus (blue wildrye)

2004 ◽  
Vol 82 (12) ◽  
pp. 1776-1789 ◽  
Author(s):  
Vicky J Erickson ◽  
Nancy L Mandel ◽  
Frank C Sorensen
Keyword(s):  
Genetic Variation ◽  
Principal Component ◽  
Common Garden ◽  
Primary Objective ◽  
Landscape Patterns ◽  
Clinal Variation ◽  
Phenotypic Variance ◽  
Seed Transfer ◽  
Wide Range ◽  
Elymus Glaucus

Source-related phenotypic variance was investigated in a common garden study of populations of Elymus glaucus Buckley (blue wildrye) from the Blue Mountain Ecological Province of northeastern Oregon and adjoining Washington. The primary objective of this study was to assess geographic patterns of potentially adaptive differentiation in this self-fertile allotetraploid grass, and use this information to develop a framework for guiding seed movement and preserving adaptive patterns of genetic variation in ongoing restoration work. Progeny of 188 families were grown for 3 years under two moisture treatments and measured for a wide range of traits involving growth, morphology, fecundity, and phenology. Variation among seed sources was analyzed in relation to physiographic and climatic trends, and to various spatial stratifications such as ecoregions, watersheds, edaphic classifications, etc. Principal component (PC) analysis extracted four primary PCs that together accounted for 67% of the variance in measured traits. Regression and cluster analyses revealed predominantly ecotypic or stepped-clinal distribution of genetic variation. Three distinct geographic groups of locations accounted for over 84% of the variation in PC-1 and PC-2 scores; group differences were best described by longitude and ecoregion. Clinal variation in PC-3 and PC-4 scores was present in the largest geographic group. Four geographic subdivisions were proposed for delimiting E. glaucus seed transfer in the Blue Mountains.Key words: Elymus glaucus, morphological variation, local adaptation, seed transfer, seed zones, polyploid.

scholarly journals Evolvability of Drought Response in Four Native and Non-native Conifers: Opportunities for Forest and Genetic Resource Management in Europe

2021 ◽  
Vol 12 ◽  
Author(s):  
Silvio Schueler ◽  
Jan-Peter George ◽  
Sandra Karanitsch-Ackerl ◽  
Konrad Mayer ◽  
Raphael Thomas Klumpp ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Norway Spruce ◽  
Common Garden ◽  
Tree Breeding ◽  
Drought Response ◽  
Silver Fir ◽  
European Larch ◽  
Drought Sensitivity ◽  
Seed Transfer ◽  
Intraspecific Genetic Variation

Intraspecific genetic variation in drought response is expected to play an important role in determining the persistence of tree populations in global change as it (1) allows for spontaneous selection and local adaptation of tree populations, (2) supports assisted seed transfer of less-drought-sensitive provenance, and (3) enables the integration of drought-sensitivity traits into tree breeding. Estimating the potential of such adaptation options requires quantitative genetic knowledge of drought sensitivity across significant parts of species distributions and a comparative assessment of genetic variation within economically and ecologically important tree species. We quantified genetic variation within and among populations of four conifers growing within common garden experiments in the drought-prone eastern Austria. This region experienced three strong drought periods between 1980 and 2010 that resulted in significant reductions in radial growth. Among the four tested species, Douglas-fir revealed the highest resistance during drought and silver fir the best recovery after drought, while European larch and Norway spruce showed the lowest resistance. High genetic variation among populations and phenotypic stability across all three drought events was found for Norway spruce and silver fir, but not for the other species. Heritability and evolvability of drought traits, both approximated via genetic repeatability, revealed strong differences among populations of all four species. Repeatability and evolvability for resistance were highest in Norway spruce and, for recovery, highest in European larch. Our comparison indicates that the mean drought sensitivity of a species is not related to the intraspecific genetic variation in drought response. Thus, also highly drought-sensitive species, such as Norway spruce and European larch, harbor significant genetic variation in drought response within and among populations to justify targeted tree breeding, assisted gene flow, and supportive forest management to foster local adaptations to future conditions.

Genetic variation in juvenile growth of tamarack (Larixlaricina) in northwestern Ontario

1993 ◽  
Vol 23 (9) ◽  
pp. 1852-1862 ◽  
Author(s):  
Robert E. Farmer Jr. ◽  
Gwenoth O'Reilly ◽  
Deng Shaotang
Keyword(s):  
Genetic Variation ◽  
Common Garden ◽  
Shoot Elongation ◽  
Allozyme Variation ◽  
Broad Sense ◽  
Population Variation ◽  
Broad Sense Heritability ◽  
Northwestern Ontario ◽  
Test Population ◽  
N 93

Nested designs incorporating provenances and families and clones within provenances were used in two common garden tests near Thunder Bay, Ont. (48°N, 84°W) to evaluate genetic variation in growth and sylleptic branching among and within populations of tamarack (Larixlaricina (Du Roi) K. Koch) from 46°N, 80°W to 53°N, 93°W. At 7 and 8 years there was a north-south trend of increasing height among provenances. Genetic variation in height was related to both rate and duration of shoot elongation, but latitudinal variation in shoot growth mainly resulted from differences in late-season elongation. There was substantial genetic variance in height within populations, and broad-sense heritability based on pooled variances was 0.23 for one test population at 8 years and 0.11 for the second at 7 years. The more vigorous southern provenances had a greater potential for sylleptic branching in the test area than northern sources, and wide within-population variation in syllepsis was under stronger genetic control than growth (broad-sense heritability = 0.47 in year 6). Patterns of genetic variation observed in the study were not congruent with patterns of morphological and allozyme variation previously reported for the sampled populations.

Mapping genetic variation and seed zones for Bromus carinatus in the Blue Mountains of eastern Oregon, USAIn this article, mention of companies or trade names does not constitute an endorsement of any product or procedure.

Botany ◽  
2010 ◽  
Vol 88 (8) ◽  
pp. 725-736 ◽  
Author(s):  
R. C. Johnson ◽  
Vicky J. Erickson ◽  
Nancy L. Mandel ◽  
J. Bradley St Clair ◽  
Kenneth W. Vance-Borland
Keyword(s):  
Environmental Variables ◽  
Regression Models ◽  
Plant Traits ◽  
Seed Source ◽  
Maximum Temperature ◽  
Blue Mountains ◽  
Seed Transfer ◽  
Bromus Carinatus ◽  
Seed Zones ◽  
Transfer Zones

Seed transfer zones ensure that germplasm selected for restoration is suitable and sustainable in diverse environments. In this study, seed zones were developed for mountain brome ( Bromus carinatus Hook. & Arn.) in the Blue Mountains of northeastern Oregon and adjoining Washington. Plants from 148 Blue Mountain seed source locations were evaluated in common-garden studies at two contrasting test sites. Data on phenology, morphology, and production were collected over two growing seasons. Plant traits varied significantly and were frequently correlated with annual precipitation and annual maximum temperature at seed source locations (P < 0.05). Plants from warmer locations generally had higher dry matter production, longer leaves, wider crowns, denser foliage, and greater plant height than those from cooler locations. Regression models of environmental variables with the first two principal components (PC 1 and PC 2) explained 46% and 40% of the total variation, respectively. Maps of PC 1 and PC 2 generally corresponded to elevation, temperature, and precipitation gradients. The regression models developed from PC 1 and PC 2 and environmental variables were used to map seed transfer zones. These maps will be useful in selecting mountain brome seed sources for habitat restoration in the Blue Mountains.

scholarly journals A Survey of Genetic Variation in Streptomyces Isolates Causing Potato Common Scab in the United States

2006 ◽  
Vol 96 (12) ◽  
pp. 1363-1371 ◽  
Author(s):  
Leslie A. Wanner
Keyword(s):  
United States ◽  
Genetic Variation ◽  
Common Scab ◽  
Disease Incidence ◽  
The United States ◽  
Rrna Gene ◽  
Population Genetic Study ◽  
Variable Regions ◽  
Genus Streptomyces ◽  
Characteristic Features

Common scab is a serious disease of potatoes and other root and tuber crops, affecting crop quality and market value. The disease is caused by gram positive soil bacteria in the genus Streptomyces. Disease incidence and severity vary in different locations and years; this is due in part to variation in the environment (weather) and genetic variation in potato cultivars. Little information is available on the contribution of genetic variation by the pathogen. To examine genetic diversity in different locations within the United States, streptomycetes were isolated from lesions on field-grown potatoes from six states. Isolates were classified into species based on sequence of variable regions in the 16s rRNA gene. The presence of genes associated with the recently described S. turgidiscabies pathogenicity island (PAI) was also determined. About half of the isolates belonged to S. scabies or S. europaeiscabiei based on 16s rDNA sequence, and had characteristic features of the PAI. They were found in all six states, and were pathogenic on potato and radish. The remaining isolates included pathogens and nonpathogens. They were varied in appearance, and represent several species, including one pathogenic species not previously reported. Some pathogenic isolates lacked one or more genes characteristic of the PAI, although all had genes for biosynthesis of the pathogenicity determinant thaxtomin. In this relatively small survey, regional differences in scab-causing streptomycetes were seen. This report furnishes tools and baseline data for population genetic study of scab-causing streptomycetes in the United States.

Genetic variation and evolutionary relationships amongst bluetongue viruses endemic in the United States

1991 ◽  
Vol 21 (2) ◽  
pp. 91-109 ◽  
Author(s):  
H.W. Heidner ◽  
L.G. Iezzi ◽  
B.I. Osburn ◽  
N.J. MacLachlan
Keyword(s):  
United States ◽  
Genetic Variation ◽  
The United States ◽  
Evolutionary Relationships

Revitalizing Difference in the HapMap: Race and Contemporary Human Genetic Variation Research

2008 ◽  
Vol 36 (3) ◽  
pp. 471-477 ◽  
Author(s):  
Jennifer A. Hamilton
Keyword(s):  
Genetic Variation ◽  
Human Genome ◽  
Genetic Research ◽  
The United States ◽  
Genome Project ◽  
Human Genetic Variation ◽  
Early 21St Century ◽  
The Social ◽  
English Speaking ◽  
The Human Genome Project

In 2000, researchers from the Human Genome Project (HGP) proclaimed that the initial sequencing of the human genome definitively proved, among other things, that there was no genetic basis for race. The genetic fact that most humans were 99.9% the same at the level of their DNA was widely heralded and circulated in the English-speaking press, especially in the United States. This pronouncement seemed proof that long-term antiracist efforts to de-biologize race were legitimized by scientific findings. Yet, despite the seemingly widespread acceptance of the social construction of race, post-HGP genetic science has seen a substantial shift toward the use of race variables in genetic research and, according to a number of prominent scholars, is re-invoking the specter of earlier forms of racial science in some rather discomfiting ways. During the past seven years, the main thrust of human genetic research, especially in the realm of biomedicine, has shifted from a concern with the 99.9% of the shared genome — what is thought to make humans alike — towards an explicit focus on the 0.1% that constitutes human genetic variation. Here I briefly explore some of the potential implications of the conceptualization and practice of early 21st century genetic variation research, especially as it relates to questions of race.

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