The structure of genetic diversity in Engelmann spruce and a comparison with blue spruce

2006 ◽  
Vol 84 (12) ◽  
pp. 1806-1828 ◽  
Author(s):  
F. Thomas Ledig ◽  
Paul D. Hodgskiss ◽  
David R. Johnson
Keyword(s):  
Genetic Diversity ◽  
Geographic Distance ◽  
Picea Engelmannii ◽  
Blue Spruce ◽  
Picea Pungens ◽  
Engelmann Spruce ◽  
Inbreeding Coefficients ◽  
Isozyme Loci ◽  
Total Diversity ◽  
The Last Glacial

Genetic diversity and genetic structure in Engelmann spruce (Picea engelmannii Parry ex Engelm.) were interpreted with respect to the effects of glacial and interglacial displacement and compared with patterns in blue spruce (Picea pungens Engelm.), which occupies a range well south of the last glacial front. On average, Engelmann spruce populations were polymorphic at 80% of 24 isozyme loci, with 2.4 alleles per locus and expected heterozygosity of 0.255. The respective means for four populations of blue spruce were 42.7%, 1.6 alleles, and 0.138. Of total diversity, 14.7% was among populations in Engelmann spruce and 8.6% in blue spruce. In Engelmann spruce, numbers of alleles increased from south to north. Recent bottlenecks were indicated in the three southernmost populations of Engelmann spruce and in the northernmost population of blue spruce. Cluster analysis divided Engelmann spruce into a northern group and a Southwestern group; however, populations from Utah were distributed among both clusters. Genetic distance was correlated with geographic distance between northern populations but not between Southwestern populations, where drift predominated over gene flow. In two Engelmann spruce populations from Utah, multilocus outcrossing rates were 0.951 (±0.016) and 0.940 (±0.071). At Flys Peak, Arizona, the southernmost location of Engelmann spruce, outcrossing was also high, 0.899 (±0.017). Thus, inbreeding coefficients observed for parental (–0.104 to 0.047) and filial (0.011 to 0.026) generations were low. Although Engelmann spruce seemed genetically robust, the evidence of bottlenecks in the southern extreme of its range suggested future problems in an era of global warming.

Adaptation of Picea engelmannii populations to the heterogeneous environments of the Intermountain West

1994 ◽  
Vol 72 (8) ◽  
pp. 1197-1208 ◽  
Author(s):  
Gerald E. Rehfeldt
Keyword(s):  
Genetic Variation ◽  
Regression Models ◽  
Cold Hardiness ◽  
Ecological Genetics ◽  
Picea Engelmannii ◽  
Heterogeneous Environments ◽  
Intermountain West ◽  
Morphometric Characters ◽  
Blue Spruce ◽  
Engelmann Spruce

Seedlings from 104 natural populations of Engelmann spruce (Picea engelmannii) and 10 blue spruce (Picea pungens) populations from the Intermountain West, U.S.A., were compared in common gardens. Comparisons involved 16 characters that described growth, development, and cold hardiness plus nine monoterpenes. Canonical discriminant analyses detected one population of blue spruce that had been misidentified, readily separated populations of blue and Engelmann spruce, suggested that three Southwest populations differed markedly from Intermountain populations of Engelmann spruce, but identified no Intermountain populations that reflected introgression with blue spruce. Genetic differences were detected among populations of Engelmann spruce for 16 of the morphometric characters, and multiple regression models accounted for as much as 70% of the variance among populations. The regressions described genetic variation occurring along clines that were dominated by elevational and latitudinal effects. The slope of the clines, however, was relatively gentle; populations located within the same physiographic province must be separated by at least 420 m in elevation before genetic differentiation becomes a reasonable possibility. By providing a means for assessing the degree by which similar genotypes recur across the landscape, the regression models have direct practical application in programs ranging from land management to conservation biology. Key words: population differentiation, genetic variation, ecological genetics.

Genetic Analysis of Chinese Cucumber Collections in the U.S. National Germplasm Collection

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 534e-534 ◽  
Author(s):  
J. Staub ◽  
Felix Sequen ◽  
Tom Horejsi ◽  
Jin Feng Chen
Keyword(s):  
Genetic Diversity ◽  
Principal Component Analysis ◽  
Genetic Variation ◽  
Genetic Analysis ◽  
Allelic Variation ◽  
Germplasm Collection ◽  
Principal Component ◽  
Isozyme Loci ◽  
National Plant Germplasm System ◽  
The U.S

Genetic variation in cucumber accessions from China was assessed by examining variation at 21 polymorphic isozyme loci. Principal component analysis of allelic variation allowed for the depiction of two distinct groupings of Chinese accessions collected in 1994 and 1996 (67 accessions). Six isozyme loci (Gpi, Gr, Mdh-2, Mpi-2, Pep-gl, and Pep-la) were important in elucidating these major groups. These groupings were different from a single grouping of Chinese 146 accessions acquired before 1994. Allelic variation in Chinese accessions allowed for comparisons with other accessions in the U.S. National Plant Germplasm System (U.S. NPGS) collection grouped by continent and sub-continent. When Chinese accessions taken collectively were compared with an array of 853 C. sativus U.S. NPGS accessions examined previously, relationships differed between accessions grouped by country or subcontinent. Data indicate that acquisition of additional Chinese and Indian cucumber accessions would be strategically important for increasing genetic diversity in the U.S. NPGS cucumber collection.

scholarly journals Comparative assessment of genetic diversity in wild and primitive cultivated barley in a center of diversity.

Genetics ◽  
1988 ◽  
Vol 119 (4) ◽  
pp. 981-990
Author(s):  
S Jana ◽  
L N Pietrzak
Keyword(s):  
Genetic Diversity ◽  
Eastern Mediterranean ◽  
Hordeum Spontaneum ◽  
Hordeum Vulgare L ◽  
Closely Related Species ◽  
Mediterranean Countries ◽  
Isozyme Loci ◽  
Cultivated Barley ◽  
Multilocus Associations ◽  
High Degree

Abstract Wild barley (Hordeum spontaneum K.) and indigenous primitive varieties of cultivated barley (Hordeum vulgare L.), collected from 43 locations in four eastern Mediterranean countries, Jordan, Syria, Turkey and Greece, were electrophoretically assayed for genetic diversity at 16 isozyme loci. Contrary to a common impression, cultivated barley populations were found to maintain a level of diversity similar to that in its wild progenitor species. Apportionment of overall diversity in the region showed that in cultivated barley within-populations diversity was of higher magnitude than the between-populations component. Neighboring populations of wild and cultivated barleys showed high degree of genetic identity. Groups of 3 or 4 isozyme loci were analyzed to detect associations among loci. Multilocus associations of varying order were detected for all three groups chosen for the analysis. Some of the association terms differed between the two species in the region. Although there was no clear evidence for decrease in diversity attributable to the domestication of barley in the region, there was an indication of different multilocus organizations in the two closely related species.

Comparison of Terpene Composition in Engelmann Spruce (Picea engelmannii) Using Hydrodistillation, SPME and PLE

2004 ◽  
Vol 59 (9-10) ◽  
pp. 641-648 ◽  
Author(s):  
Marek Mardarowicz ◽  
Dorota Wianowska ◽  
Andrzej L. Dawidowicz ◽  
Ryszard Sawicki
Keyword(s):  
Essential Oils ◽  
Steam Distillation ◽  
Solid Phase ◽  
Picea Engelmannii ◽  
Enzymatic Reactions ◽  
Plant Materials ◽  
Engelmann Spruce ◽  
Pressurised Liquid Extraction ◽  
Conifer Trees ◽  
Spruce Needles

Abstract Terpenes emitted by conifer trees are generally determined by analysing plant extracts or essential oils, prepared from foliage and cones using steam distillation. The application of these procedures limits experiments to cut plant materials. Recently headspace techniques have been adopted to examine terpene emission by living plants. This paper deals with the application of solid-phase micro-extraction (SPME) for the analysis of terpenes emitted by conifers foliage of Engelmann spruce (Picea engelmannii), including its seedlings. The compositions of SPME extracts obtained for destroyed and non-destroyed old and juvenile spruce needles were compared with the compositions of essential oils and pressurised liquid extraction (PLE) extracts corresponding to the same plant materials. No substantial differences have been found in the qualitative terpene composition estimated by analysing essential oil and PLE and SPME extracts from non-destroyed old and juvenile foliage. The disintegration of spruce needles results in the formation of a significant amount of myrcene in the case of the old conifer foliage and non-terpenoic compounds in the case of juvenile conifer foliage. This phenomenon can be attributed to enzymatic reactions occurring in the destroyed plant cells.

Inheritance of isozymes in seed and bud tissues of blue and Engelmann spruce

Genome ◽  
1987 ◽  
Vol 29 (2) ◽  
pp. 239-246 ◽  
Author(s):  
S. G. Ernst ◽  
D. E. Keathley ◽  
J. W. Hanover
Keyword(s):  
Acid Phosphatase ◽  
Key Words ◽  
Malate Dehydrogenase ◽  
Glutamate Oxaloacetate Transaminase ◽  
Blue Spruce ◽  
Mating Design ◽  
Engelmann Spruce ◽  
Enzyme Systems ◽  
Segregation Ratios ◽  
Mode Of Inheritance

Thirteen loci from 11 enzyme systems were identified among full-sib and half-sib progeny of blue and Engelmann spruce. Eleven of the loci were expressed in bud, embryo, and megagametophyte tissue; the remaining two loci were expressed only in embryo and megagametophyte tissue. There were no mobility differences observed between loci expressed in seed and bud tissues. The mode of inheritance for 10 of the loci was confirmed based on progeny genotypic distributions. For the two loci not expressed in bud tissue, acid phosphatase (Acp-2) and diaphorase (Dia-2), inheritance was inferred from pooled segregation ratios of megagametophytes from open-pollinated seed from heterozygous females. The inheritance of glutamate oxaloacetate transaminase (Got-3) was also inferred from segregation ratios and diploid embryo phenotypes of open-pollinated progeny owing to a lack of variability at this locus among the 40 parents in the mating design. Two loci, aldolase (Ald) and malate dehydrogenase (Mdh-2), were monomorphic among the 20 parents of both species. Key words: isozymes, Engelmann spruce, blue spruce, Picea.

Factors influencing understory seedling establishment of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies lasiocarpa) in southeast Wyoming

1982 ◽  
Vol 60 (12) ◽  
pp. 2753-2761 ◽  
Author(s):  
Alan K. Knapp ◽  
William K. Smith
Keyword(s):  
Seedling Establishment ◽  
Rocky Mountain ◽  
Field Measurements ◽  
Incident Radiation ◽  
Picea Engelmannii ◽  
Abies Lasiocarpa ◽  
Northern Rocky Mountains ◽  
Medicine Bow Mountains ◽  
Engelmann Spruce ◽  
Surface Drying

Although seedlings of Abies lasiocarpa are generally more abundant than those of Picea engelmannii in the understory of mature spruce–fir forests throughout the central and northern Rocky Mountains, little information exists concerning environmental or plant factors that may influence the establishment of these two conifers. Field measurements in the Medicine Bow Mountains of southeast Wyoming showed that seedlings of A. lasiocarpa had greater photosynthetic rates at low understory light levels and required lower levels of incident radiation for saturation of photosynthesis compared with those of P. engelmannii. However, both conifers occurred in understory locations where total daily solar radiation was equally low (<2 MJ∙m−2∙day−1) and thus, a lack of light did not appear to be responsible for the low number of P. engelmannii seedlings in the understory. In contrast, seedlings of P. engelmannii were substantially more abundant at locations with thinner litter layers compared with those of A. lasiocarpa. Also, laboratory studies showed that the smaller seeds of P. engelmannii germinated more rapidly and at lower temperatures than seeds of A. lasiocarpa although growth of tap roots on A. lasiocarpa seedlings was greater initially ([Formula: see text] longer in 2-week-old seedlings) as well as for 10-week-old seedlings (50% longer). The deeper penetrating tap root of A. lasiocarpa seedlings may enable this conifer to establish more abundantly on thick, rapidly drying litter layers that are characteristic of mature spruce–fir forests. In contrast, establishment of P. engelmannii seedlings may be limited to microsites without a thick litter layer such as disturbed areas or decomposing wood, where surface drying may occur more gradually throughout the summer. These results are discussed in terms of the potential effects of seedling establishment on the observed patterns in climax vegetation of central and northern Rocky Mountain subalpine forests.

scholarly journals Statistical analysis in support of maintaining a healthy traditional Siamese cat population

2021 ◽  
Vol 53 (1) ◽  
Author(s):  
Arthur M. A. Pistorius ◽  
Ineke Blokker
Keyword(s):  
Genetic Diversity ◽  
Cluster Analysis ◽  
Companion Animals ◽  
Hereditary Diseases ◽  
Small Scale ◽  
Genetic Traits ◽  
Inbreeding Coefficients ◽  
A Value ◽  
Siamese Cat ◽  
Line Breeding

Abstract Background For many years, breeders of companion animals have applied inbreeding or line breeding to transfer desirable genetic traits from parents to their offspring. Simultaneously, this resulted in a considerable spread of hereditary diseases and phenomena associated with inbreeding depression. Results Our cluster analysis of kinship and inbreeding coefficients suggests that the Thai or traditional Siamese cat could be considered as a subpopulation of the Siamese cat, which shares common ancestors, although they are considered as separate breeds. In addition, model-based cluster analysis could detect regional differences between Thai subpopulations. We show that by applying optimal contribution selection and simultaneously limiting the contributions by other breeds, the genetic diversity within subpopulations can be improved. Conclusion In principle, the European mainland Thai cat population can achieve a genetic diversity of about 26 founder genome equivalents, a value that could potentially sustain a genetically diverse population. However, reaching such a target will be difficult in the absence of a supervised breeding program. Suboptimal solutions can be obtained by minimisation of kinships within regional subpopulations. Exchanging animals between different regions on a small scale might be already quite useful to reduce the kinship, by achieving a potential diversity of 23 founder genome equivalents. However, contributions by other breeds should be minimised to preserve the original Siamese gene pool.

Geographic patterns of genetic diversity in North American trees: a continent-wide analysis

2021 ◽  
Author(s):  
Andrew V. Gougherty
Keyword(s):  
Genetic Diversity ◽  
Population Genetics ◽  
North America ◽  
North American ◽  
Tree Species ◽  
Geographic Patterns ◽  
Study Characteristics ◽  
Dispersal Traits ◽  
The Last Glacial Maximum ◽  
The Last Glacial

In the northern hemisphere, many species have been reported to have greater genetic diversity in southern populations than northern populations - ostensibly due to migration northward following the last glacial maximum (LGM). The generality of this pattern, while well-established for some taxa, remains unclear for North American trees. To address this issue, I collected published population genetics data for 73 North American tree species, and tested whether genetic diversity was associated with latitude or longitude and whether geographic trends were associated with dispersal traits, range or study characteristics. I found there were no general geographic patterns in genetic diversity, and the strength of the geographic gradients were not associated with any species or study characteristics. Species in the northern and western regions of North America tended to have more species with genetic diversity that declined with latitude, but most species had no significant trend. This work shows that North American trees have complex, individualistic, patterns of genetic diversity that may negate explanation by any particular dispersal trait or range characteristic.

Detection of genetic diversity in rough fescue (Festuca campestris Rydb) populations of southern Alberta and British Columbia, Canada, using RAPD markers

2008 ◽  
Vol 88 (2) ◽  
pp. 307-312
Author(s):  
Zhao Mengli ◽  
Han Bing ◽  
Walter D Willms
Keyword(s):  
Genetic Diversity ◽  
British Columbia ◽  
Genetic Distance ◽  
Random Amplified Polymorphic Dna ◽  
Geographic Distance ◽  
Genetic Distances ◽  
Gene Frequencies ◽  
Southern Alberta ◽  
Potential Adaptation ◽  
Rough Fescue

Mountain rough fescue (Festuca campestris Rydb.) is a tufted native grass in southern Alberta and British Columbia, Canada, and has attracted interest for use in reclamation. However, its seed is often available from only a few localized sources and may not be adapted for areas removed from the collection site. We conducted a study to determine the genetic variability among rough fescue populations to assess its potential adaptation. Thirty plants were collected from each of six populations and analyzed using Random Amplified Polymorphic DNA (RAPD). One population (Kamloops, BC) was separated by several mountain ranges from the five easterly Alberta populations.The Kamloops population was also separated from the Alberta populations by genetic distance in two clusters. Of the total genetic variation present in the data, 21% was found among populations while the remaining (79%) was found within populations. Nei’s genetic distances among populations were related to their geographical distances. Genetic differences among populations appeared to be caused primarily by differences in gene frequencies rather than rare genes. Also, genetic diversity appeared to increase from west to east suggesting that the more easterly populations had greater adaptation potential. We speculate that the more easterly populations are less likely to share genes since the prevailing winds are from the west. Germplasm from the more easterly populations may be used with suitable precautions within Alberta and possibly around Kamloops. Key words: Genetic distance, geographic distance, reclamation, potential adaptation

Lignocellulose degradation by Fusarium species

1983 ◽  
Vol 61 (4) ◽  
pp. 1194-1198 ◽  
Author(s):  
John B. Sutherland ◽  
Anthony L. Pometto III ◽  
Don L. Crawford
Keyword(s):  
Wheat Straw ◽  
Degradation Products ◽  
Fusarium Species ◽  
Water Soluble ◽  
Lignocellulose Degradation ◽  
Blue Spruce ◽  
Picea Pungens ◽  
Weight Losses ◽  
Aromatic Degradation ◽  
Different Strains

Eighteen strains of fungi in the genus Fusarium, including varieties of F. episphaeria, F. lateritium, F. moniliforme, F. nivale, F. oxysporum, F. rigidiusculum, F. roseum, F. solani, and F. tricinctum, slowly degraded lignocelluloses from blue spruce (Picea pungens) and wheat (Triticum aestivum). When grown with [lignin-14C]lignocellulose from blue spruce, 15 of the Fusarium strains converted 2.2 to 4.3% of the [14C]lignin in 60 days to 14CO2 and 3.9 to 8.4% to labeled water-soluble products. When grown with unlabeled lignocellulose from wheat straw, the strains caused total weight losses in 60 days of 7 to 25%, acid-insoluble (Klason) lignin losses of 2 to 17%, and carbohydrate losses of 3 to 33%. Crude protein contents of degraded wheat-straw lignocellulose samples were 3.2 to 5.1%. Among the aromatic degradation products from wheat-straw lignocellulose degraded by different strains, as shown by gas chromatography, were p-coumaric acid, vanillic acid, vanillin, syringaldehyde, and p-hydroxybenzaldehyde.

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