Temporal differences in genetic diversity and structure of sugar maple in an old-growth forest

1992 ◽  
Vol 22 (10) ◽  
pp. 1504-1509 ◽  
Author(s):  
Stephanie A. Foré ◽  
R. James Hickey ◽  
Sheldon I. Guttman ◽  
John L. Vankat
Keyword(s):  
Sugar Maple ◽  
Gene Diversity ◽  
Genotype Frequency ◽  
Starch Gel Electrophoresis ◽  
Nature Preserve ◽  
Old Growth Forest ◽  
Genetic Diversity And Structure ◽  
Significant Difference ◽  
Starch Gel ◽  
Enzyme Patterns

Genetic data were collected for five developmentally based cohorts of Acersaccharum Marsh in a large southwestern Ohio nature preserve. A minimum of 48 individuals were sampled from each of the following cohorts: embryos, 1st-year seedlings, and three diameter at breast height classes (≤ 2, 15–25, and ≥ 40 cm). Genotypes at eight loci were inferred from phenotypic enzyme patterns of seven enzymes extracted from cambial tissue and resolved by starch gel electrophoresis. Allelic data were subdivided by cohort and statistically compared. There was no significant difference in observed heterozygosity among the cohorts. Nei's gene diversity statistics, Nei's unbiased genetic distance, and χ2 analyses of allele and genotype frequency heterogeneity indicated that there was little genetic differentiation among cohorts. The observed differentiation resulted from allele and genotype frequency differences between seedlings and other cohorts.

Isozyme variation in the fungus Atkinsonella hypoxylon within and among populations of its host grasses

1989 ◽  
Vol 67 (9) ◽  
pp. 2600-2607 ◽  
Author(s):  
Adrian Leuchtmann ◽  
Keith Clay
Keyword(s):  
Gel Electrophoresis ◽  
Gene Diversity ◽  
Host Population ◽  
Multilocus Genotype ◽  
Isozyme Variation ◽  
Starch Gel Electrophoresis ◽  
Gene Exchange ◽  
Multilocus Genotypes ◽  
Starch Gel ◽  
Atkinsonella Hypoxylon

Isozyme variation of 291 isolates of Atkinsonella hypoxylon (Clavicipitaceae, tribe Balansieae) from 24 populations of its four known host grasses (Danthonia compressa, Danthonia sericea, Danthonia spicata, and Stipa leucotricha) was examined using starch gel electrophoresis. In total, there were 20 distinct multilocus genotypes. Eleven out of 13 enzyme loci (84.6%) exhibited more than one allele (mean 2.8) per locus. Nei's total gene diversity (HT) within all isolates was 0.229. Between isolate samples from S. leucotricha and the three Danthonia hosts, Nei's genetic identity (I) ranged from 0.21 to 0.31 and among isolate samples from the three Danthonia species I ranged from 0.65 to 0.88, with isolates from D. spicata and D. compressa being most similar. Variation of A. hypoxylon occurred both within and among populations of D. spicata and D. compressa, where up to 53 isolates were sampled per host population. In contrast, all 20 isolates from S. leucotricha were identical, as were all 6 from D. sericea. A few isolates from D. spicata exhibited the same, unusual multilocus genotype with unique alleles at six different loci. The occurrence of several multilocus genotypes in isolates from the same ascostroma and the 1:1 segregation of genotypes among ascospores from a single ascus indicated gene exchange among sexually reproducing individuals, consistent with a heterothallic mating system for A. hypoxylon.

Genetic variation in populations of the endemic Achillea millefolium ssp. megacephala from the Athabasca sand dunes and the widespread ssp. lanulosa in western North America

1996 ◽  
Vol 74 (7) ◽  
pp. 1138-1146 ◽  
Author(s):  
Brett G. Purdy ◽  
Randall J. Bayer
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Diversity ◽  
Sand Dunes ◽  
Achillea Millefolium ◽  
Starch Gel Electrophoresis ◽  
Widespread Species ◽  
Polymorphic Loci ◽  
Endemic Taxon ◽  
Starch Gel

As part of an analysis of genetic diversity in endemic taxa of the Athabasca sand dunes in northern Saskatchewan, Canada, genetic variation was examined by starch gel electrophoresis in six populations of the endemic Achillea millefolium ssp. megacephala, and 13 populations of the closely related widespread taxon, A. millefolium ssp. lanulosa. Endemic populations had more alleles per locus, a higher percentage of polymorphic loci, and greater genetic diversity than did populations of the widespread taxon. At polymorphic loci, total gene diversity was comparable in both taxa, although within-population gene diversity was higher in the endemic taxon. Population differentiation (GST) was considerably lower in ssp. megacephala than in ssp. lanulosa, although GST values were reduced when the parameter was calculated separately for geographic subdivisions of the widespread taxon. Our results differ from previous studies in which the endemic is typically depauperate of genetic variation relative to related widespread species. We suggest that obligate sexual reproduction and the absence of long-term asexual reproduction may be one of a number of factors that help populations of ssp. megacephala maintain higher levels of genetic variation on the Athabasca sand dunes. Keywords: genetic variation, endemic, rare species, Athabasca sand dunes, Achillea millefolium.

ELECTROPHORETIC ANALYSIS OF DIVERSITY WITHIN CUPRESSUS SEMPERVIRENS L. GROWING IN ISRAEL

1997 ◽  
Vol 45 (1) ◽  
pp. 1-8
Author(s):  
Gabriel Schiller ◽  
Leonid Korol
Keyword(s):  
Gel Electrophoresis ◽  
Gene Diversity ◽  
Electrophoretic Analysis ◽  
Starch Gel Electrophoresis ◽  
Cupressus Sempervirens ◽  
Single Tree ◽  
Enzyme Systems ◽  
High Gene ◽  
Starch Gel ◽  
Viable Seeds

Isoenzyme variants withinCupressus sempervirensL. planted in Israel have been identified using starch gel electrophoresis of enzymes extracted from the megagametophytic and perisperm seed tissue. Single-tree cone collection from 493 trees growing in 27 populations at holy sites and in plantations planted at the end of the 19th and the beginning of the 20th century in the country was done in 1986–1987. In 1994 viable seeds were available from only 267; of them, 140 trees were phenotypically identified as var.pyramidalisand 67 as being of var.horizontalis; the other 60 trees were not identified phenotypically. The results gained show that in the plantedC. sempervirensL. under investigation 11 (47.8%) out of the 23 gene loci in 13 enzyme systems analyzed were polymorphic; they contain a relatively high gene diversity of 0.479. The genetic distance between the two varieties planted in Israel is 0.007. Differences in allele frequencies between the two varieties occurred only in 5 loci, viz., IDH2PGI2, MDH3, PGM1, and ACO1.

Genetic structure after forest fragmentation: a landscape ecology perspective on Acer saccharum

1992 ◽  
Vol 70 (8) ◽  
pp. 1659-1668 ◽  
Author(s):  
Stephanie A. Foré ◽  
R. James Hickey ◽  
John L. Vankat ◽  
Sheldon I. Guttman ◽  
Robert L. Schaefer
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Forest Fragmentation ◽  
Acer Saccharum ◽  
Sugar Maple ◽  
Fragmented Landscape ◽  
Starch Gel Electrophoresis ◽  
Long Distance ◽  
Local Populations ◽  
Genetic Diversity And Structure

Fragmentation of large expanses of forests into small stands has isolated local populations of organisms. Sugar maple (Acer saccharum) was used to determine if the degree of forest fragment isolation affects genetic diversity and structure of local populations. Genetic data were collected from canopy (prefragmentation) and juvenile (postfragmentation) individuals in 15 woodlots. Genotypes were inferred from phenotypic enzyme patterns of seven enzymes representing eight loci extracted from cambium and resolved with starch gel electrophoresis. Analyses of allelic data indicated that genetic diversity was not significantly different between juvenile or canopy subdivisions, or between woodlots with low and high degrees of isolation. Genetic differentiation among woodlots was significantly greater for the canopy than for the juvenile subdivision. Estimates of gene flow indicate that postfragmentation gene flow rates are higher than prefragmentation rates. Apparently, sugar maple's high potential for long-distance gene flow is enhanced by altered wind flux across a fragmented landscape. The results also show that forest fragmentation does not always result in greater isolation of local populations. Key words: sugar maple, gene flow, conservation, isolation, allozymes.

Genetic variation in trembling aspen in Ontario based on isozyme studies

1987 ◽  
Vol 17 (9) ◽  
pp. 1134-1138 ◽  
Author(s):  
Jung O. Hyun ◽  
Om P. Rajora ◽  
Louis Zsuffa
Keyword(s):  
Gene Diversity ◽  
Fixation Index ◽  
Starch Gel Electrophoresis ◽  
Root Tips ◽  
Young Root ◽  
Isozyme Loci ◽  
Starch Gel ◽  
The Mean ◽  
Geographic Regions ◽  
East West

Isoenzyme studies were conducted on root tips of 200 Populustremuloides clones selected from eight geographic regions (populations) along north–south and east–west transects in Ontario. Starch gel electrophoresis was used to assay crude enzyme extracts from young root rips of rooted suckers obtained from the clones sampled. A total of 15 isozyme loci coding for eight different enzyme systems were resolved. The mean of total gene diversity was 0.252. An average of 79% of the loci were polymorphic in any one population, with an average of 2.7 alleles per locus. More than 90% of the genetic variability could be attributed to within-population differentiation. A deficiency of observed heterozygotes was calculated for all populations studied. The fixation index averaged 0.462. The genetic distance estimates among populations had an overall mean of 0.103. There was no correlation between genetic and geographic distances. Results of this study suggest this species in its Ontario range is genetically variable and moderately differentiated.

scholarly journals Foetal-Maternal Blood Respiratory Properties of an Ovoviviparous Snake the Cottonmouth, Agkistrodon Piscivorus

1984 ◽  
Vol 108 (1) ◽  
pp. 247-255 ◽  
Author(s):  
GEOFFREY F. BIRCHARD ◽  
CRAIG P. BLACK ◽  
GORDON W. SCHUETT ◽  
VIRGINIA BLACK
Keyword(s):  
Haemoglobin Concentration ◽  
Oxygen Affinity ◽  
Maternal Blood ◽  
Nucleoside Triphosphate ◽  
Starch Gel Electrophoresis ◽  
Agkistrodon Piscivorus ◽  
Significant Difference ◽  
Starch Gel ◽  
Blood Oxygen Affinity ◽  
Hill Coefficients

The respiratory properties of maternal, foetal and juvenile whole blood were studied in the ovoviviparous snake, Agkistrodon piscivorus. Haematocrit, haemoglobin concentration, O2 capacity, Bohr effect and Hill coefficients were not significantly different in foetal and maternal blood and were similar to values previously reported from snakes. A significant difference in foetal-maternal blood P50 (foetal 19.5, maternal 48.8) was found. Nucleoside triphosphate (NTP) levels were lower in foetal than in maternal and juvenile snakes. The foetal-maternal difference in P50 and NTP levels disappeared soon after birth (juvenile P50 45.5). Starch gel electrophoresis revealed no difference in foetal and maternal haemoglobins. We suggest that the foetal-maternal shift in blood oxygen affinity is modulated directly and/or indirectly by NTP levels. Note:

Bovine Platelet Proteins II. Purification of Platelet Fibrinogen

1969 ◽  
Vol 21 (03) ◽  
pp. 419-427 ◽  
Author(s):  
N. O Solum ◽  
S Łopaciuk
Keyword(s):  
Analytical Ultracentrifugation ◽  
Insoluble Fraction ◽  
Disc Electrophoresis ◽  
Plasma Fibrinogen ◽  
Starch Gel Electrophoresis ◽  
Freezing And Thawing ◽  
Insoluble Material ◽  
High Resolution Power ◽  
Starch Gel ◽  
Platelet Proteins

Summary1. Platelet fibrinogen has been purified from washed bovine platelets. The procedure was based on the methods for purification of plasma fibrinogen by fractionated precipitations and extractions with ethanol and glycine below 0°, and precipitation of proteins by dimethylformamide at 0°.2. The platelet extract obtained by freezing and thawing of the cells, freed from insoluble material by centrifugation at 23,000 x g for 30 min, contained 0.22 ±0.003mg fibrinogen per 109 platelets. Total protein of this fraction was 0.77 ±0.08 mg per 109 platelets whereas that of the insoluble fraction was 0.79 ±0.09 mg per 109 platelets.3. The most purified platelet fibrinogen fraction contained 91-98% of the protein in a thrombin-clottable state. The yield was approx. 20%. It showed homogeneity in analytical ultracentrifugation, in immunoelectrophoresis using an antiserum produced by immunization of rabbits against platelet extract, and in starch gel electrophoresis using a discontinuous system of Tris HCl and borate buffers offering a high resolution power towards the platelet proteins. Polyacrylamide disc electrophoresis revealed two to three faint lines behind the main fibrinogen line. At least one such line was also observed with purified plasma fibrinogen.

Fractionation of Plasminogen by Starch Gel Electrophoresis

1964 ◽  
Vol 12 (01) ◽  
pp. 126-136 ◽  
Author(s):  
Karl H. Slotta ◽  
J. D Gonzalez
Keyword(s):  
Gel Electrophoresis ◽  
Room Temperature ◽  
Broad Band ◽  
Caproic Acid ◽  
Starch Gel Electrophoresis ◽  
Full Activity ◽  
Veronal Buffer ◽  
Starch Gel ◽  
Alkaline Range

SummaryWhen urea or ε-amino caproic acid were used as solublizing agents for plasminogen in electrophoretic experiments, only one broad band of the proenzyme was obtained on acetate cellulose, in starch block, and in acrylamide gel. In starch gel electrophoresis, however, both forms of plasminogen – the native or euglobulin and Kline’s or Pseudoglobulin plasminogen – separated into six bands. These migrated toward the cathode at room temperature in borate or veronal buffer in the alkaline range and showed full activity in fibrinagar-streptokinase plates.

scholarly journals PROTEIN POLYMORPHISMS, SEGREGATION IN GENETIC CROSSES AND GENETIC DISTANCES AMONG FISHES OF THE GENUS XIPHOPHORUS (POECILIIDAE)

Genetics ◽  
1982 ◽  
Vol 102 (3) ◽  
pp. 539-556
Author(s):  
Don C Morizot ◽  
Michael J Siciliano
Keyword(s):  
Goodness Of Fit ◽  
Inbred Strains ◽  
Interspecific Backcross ◽  
Genetic Distances ◽  
Rapid Expansion ◽  
Starch Gel Electrophoresis ◽  
Lower Vertebrate ◽  
Protein Coding ◽  
Group I ◽  
Starch Gel

ABSTRACT The products of 49 protein-coding loci were examined by starch gel electrophoresis for populational variation in six species of Xiphophorus fishes and/or segregation in intra- and interspecific backcross and intercross hybrids. Electrophoretic variation was observed for 29 of the 35 locus products in a survey of 42 population samples. The highest frequency of polymorphic loci observed in noninbred populations was 0.143. After ten or more generations of inbreeding, all loci studied were monomorphic. Inbred strains generally exhibited the commonest electrophoretic alleles of the population from which they were derived. An assessment of genetic distances among Xiphophorus populations reflected classical systematic relationships and suggested incipient subspeciation between X. maculatus from different drainages as well as several species groups. Thirty-three loci were analyzed with respect to segregation in hybrids. The goodness of fit of segregations to Mendelian expectations at all loci analyzed (except loci in linkage group I) is interpreted as evidence for high genetic compatibility of the genomes of Xiphophorus species. It is anticipated that these data will result in a rapid expansion of the assignment of protein-coding loci to linkage groups in these lower vertebrate species.

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