Temporal components of genetic variation in migrating and wintering American wigeon

1993 ◽  
Vol 71 (11) ◽  
pp. 2229-2235 ◽  
Author(s):  
Olin E. Rhodes Jr. ◽  
Loren M. Smith ◽  
Ronald K. Chesser
Keyword(s):  
Genetic Variation ◽  
Gene Diversity ◽  
High Plains ◽  
Genetic Characteristics ◽  
Total Genetic Variation ◽  
Breeding Populations ◽  
Wintering Waterfowl ◽  
Breeding Grounds ◽  
Average Proportion ◽  
Wintering Population

Data from allele frequencies of wintering American wigeon (Anas americana) from the Southern High Plains (SHP) of Texas were used to monitor changes in genetic characteristics of the wintering population through time, and to estimate the average proportion of total genetic variation partitioned among parent breeding populations. Wigeon were surveyed electrophoretically for genetic variation at 25 biochemical loci. Changes in total gene diversity were observed throughout the study period (5 October 1988 to 15 March 1989) at numerous loci. Significant temporal changes in the genetic composition of the wintering population were detected, and a minimum of 7% of the total genetic variation in these wigeon was thought to be partitioned among the breeding populations represented on the SHP. A new influx of migrating wigeon, weather-related movements of wigeon, or spatial subdivision of breeding populations on the SHP may be responsible for shifts observed in the genetic characteristics of the wintering population. Significant heterozygote deficiencies in the sample of wintering wigeon suggest that this species maintains some degree of genetic structure on the breeding grounds. Genetic data collected from wintering waterfowl may provide minimum expectations of the degree of genetic subdivision among breeding populations and may help waterfowl biologists to detect changes in the composition of wintering waterfowl populations through time.

Apportionment of genetic variance in migrating and wintering mallards

1995 ◽  
Vol 73 (6) ◽  
pp. 1182-1185 ◽  
Author(s):  
Olin E. Rhodes Jr. ◽  
Ronald K. Chesser ◽  
Loren M. Smith
Keyword(s):  
Genetic Variation ◽  
Genetic Information ◽  
Genetic Variance ◽  
Anas Platyrhynchos ◽  
Genetic Data ◽  
High Plains ◽  
Southern High Plains ◽  
Total Genetic Variation ◽  
Breeding Populations ◽  
Wintering Areas

Mallards (Anas platyrhynchos, n = 289) wintering in the Southern High Plains of Texas were collected from 15 October 1988 to 7 February 1989 and electrophoretically surveyed for genetic variation at 30 biochemical loci. Genetic data were used to detect mixtures of breeding populations in the wintering aggregation of mallards that migrate into the Southern High Plains and to estimate the proportion of total genetic variation partitioned among breeding populations represented on the study area there. Wintering mallards represented mixtures of genetically heterogeneous breeding populations with a minimum of 10.4 – 11.7% of the genetic variation partitioned among populations represented. Genetic information may be useful in detecting mixtures of breeding populations in specific wintering areas within and among flyways.

scholarly journals Global Hierarchical Gene Diversity Analysis Suggests the Fertile Crescent Is Not the Center of Origin of the Barley Scald Pathogen Rhynchosporium secalis

2006 ◽  
Vol 96 (9) ◽  
pp. 941-950 ◽  
Author(s):  
Pascal L. Zaffarano ◽  
Bruce A. McDonald ◽  
Marcello Zala ◽  
Celeste C. Linde
Keyword(s):  
Genetic Variation ◽  
Mating Type ◽  
Gene Diversity ◽  
Local Level ◽  
Geographic Distance ◽  
Hordeum Spontaneum ◽  
Rhynchosporium Secalis ◽  
Center Of Origin ◽  
Total Genetic Variation ◽  
Fertile Crescent

A total of 1,366 Rhynchosporium secalis isolates causing scald on barley, rye, and wild barley (Hordeum spontaneum) were assayed for restriction fragment length polymorphism loci, DNA fingerprints, and mating type, to characterize global genetic structure. The isolates originated from 31 field populations on five continents. Hierarchical analysis revealed that more than 70% of the total genetic variation within regions was distributed within a barley field. At the global level, only 58% of the total genetic variation was distributed within fields, while 11% was distributed among fields within regions, and 31% was distributed among regions. A significant correlation was found between genetic and geographic distance. These findings suggest that gene flow is common at the local level while it is low between regions on the same continent, and rare between continents. Analyses of multilocus associations, genotype diversity, and mating type frequencies indicate that sexual recombination is occurring in most of the populations. We found the highest allele richness in Scandinavia followed by Switzerland. This suggests that R. secalis may not have originated at the center of origin of barley, the Fertile Crescent, nor in a secondary center of diversity of barley, Ethiopia.

Enzyme variation in natural populations of Sitka spruce (Piceasitchensis). 1. Genetic variation patterns among trees from 10 IUFRO provenances

1980 ◽  
Vol 10 (3) ◽  
pp. 415-422 ◽  
Author(s):  
Francis C. Yeh ◽  
Yousry A. El-Kassaby
Keyword(s):  
Genetic Variation ◽  
Gene Diversity ◽  
Natural Populations ◽  
Sitka Spruce ◽  
Genetic Distances ◽  
Pairwise Comparisons ◽  
A Value ◽  
Variation Patterns ◽  
Average Proportion ◽  
Geographic Sources

Genetic variation at 24 enzyme loci was studied for 10 IUFRO populations of Sitka spruce (Piceasitchensis (Bong.) Carr.). The average proportion of polymorphic loci per population was 0.51 ± 0.02 and the average proportion of heterozygous loci per individual was 0.15 ± 0.03. The following generalizations were advanced: (1) the amount of genetic polymorphism varied considerably from locus to locus; (2) many populations were similar in the amount and pattern of genetic variation for most loci; (3) but some loci had large differences among populations.Eight percent of the gene diversity was attributed to interpopulation differentiation; 92% of the total gene diversity resided within populations. Pairwise comparisons of genetic distances averaged 0.014, a value which reflected very little differentiation between geographic sources.

scholarly journals Population genetic variation analysis of bitter gourd wilt caused by Fusarium oxysporum f. sp. momordicae in China using inter simple sequence repeats (ISSR) molecular markers

2021 ◽  
Author(s):  
Rui Zang ◽  
Ying Zhao ◽  
Kangdi Guo ◽  
Kunqi Hong ◽  
Huijun Xi ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Genetic Differentiation ◽  
Fusarium Oxysporum ◽  
Diversity Index ◽  
Gene Diversity ◽  
Pcr Amplification ◽  
Bitter Gourd ◽  
Diseased Plant ◽  
Variation Analysis ◽  
Group I

AbstractBitter gourd wilt caused by Fusarium oxysporum f. sp. momordicae (FOM) is a devastating crop disease in China. A total of 173 isolates characteristic of typical Fusarium oxysporum with abundant microconidia and macroconidia on white or ruby colonies were obtained from diseased plant tissues. BLASTn analysis of the rDNA-ITS of the isolates showed 99% identity with F. oxysporum species. Among the tested isolates, three were infectious toward tower gourd and five were pathogenic to bottle gourd. However, all of the isolates were pathogenic to bitter gourd. For genetic differences analysis, 40 ISSR primers were screened and 11 primers were used for ISSR-PCR amplification. In total, 127 loci were detected, of which 76 were polymorphic at a rate of 59.84%. POPGENE analysis showed that Nei’s gene diversity index (H) and Shannon’s information index (I) were 0.09 and 0.15, respectively, which indicated that the genetic diversity of the 173 isolates was low. The coefficient of gene differentiation (Gst = 0.33 > 0.15) indicated that genetic differentiation was mainly among populations. The strength of gene flow (Nm = 1.01 > 1.0) was weak, indicating that the population differentiation caused by gene drift was blocked to some degree. The dendrogram based on ISSR markers showed that the nine geographical populations were clustered into two groups at the threshold of genetic similarity coefficient of 0.96. The Shandong and Henan populations were clustered into Group I, while the Guangdong, Hainan, Guangxi, Fujian, Jiangxi, and Hubei populations constituted Group II. Results of the genetic variation analysis showed that the Hunan and Guangxi populations had the highest degree of genetic differentiation, while the Hubei population had the lowest genetic differentiation. Our findings enrich the knowledge of the genetic variation characteristics of FOM populations with the goal of developing effective disease-management programs and resistance breeding programs.

scholarly journals RAPD ANALYSIS OF GENETIC VARIATION IN NATURAL POPULATIONS OF AEGILOPS SP. FROM SOUTH ADRIATIC

AGROFOR ◽  
2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Miodrag DIMITRIJEVIĆ ◽  
Sofija PETROVIĆ ◽  
Borislav BANJAC ◽  
Goran BARAĆ
Keyword(s):  
Genetic Variation ◽  
Food Production ◽  
Rapd Markers ◽  
Rapd Analysis ◽  
Gene Diversity ◽  
Rapd Marker ◽  
Natural Populations ◽  
Genetic Structuring ◽  
Potential Source ◽  
Novel Approach

New challenges that food production is facing, requires novel approach inagricultural strategy. The scissors of growing demand for food and the limits of theEarth's resources are forcing plant breeders to run for the new borders, utilizing allthe available genetic variation in order to create fruitful and economically soundcultivars. Aegilops sp. (Poaceae) is a potential source of genetic variation for wheatimprovement. RAPD marker analysis was used in order to distinguish and evaluatedifferent genotypes of Aegilops sp. population samples from the collectiongathered during few years’ expeditions in South Adriatic, along the coastal, littoraland the inland parts of Montenegro. Ten randomly amplified polymorphic DNAmarkers (RAPDs) were tested: OPA-05, OPA-08, OPB-06, OPA-02, OPA-07,OPA-25, OPB-07, OPB-18, OPC-06, OPC-10 to examine genetic structuring on 18samples of 6 populations of different Aegilops sp. According to global AMOVA,75% of total gene diversity was attributable mostly to diversity within population(ΦPT =0.205 p=0.001), indicating that the groups of studied goat grass populationswere seemingly to differing genetically. In contrast, 25% of the variation camefrom variation among populations. According to PCoA, the distribution of 18 goatgrass accessions by Principal Coordinate Analysis shows 3 distinct groups. PCoaxis 1, PCo axis 2, and PCo axis 3 account for 20.8%, 18.2% and 14.1% of thevariation, respectively. The results showed that RAPD markers could be aconvenient tool for investigating genetic variation and for detecting geneticstructuring of populations. Genetic variability formed under natural selection wasentrenched.

scholarly journals Genetic studies revealed differences between European and North American populations of Calypogeia azurea

2016 ◽  
Vol 42 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Katarzyna Buczkowska ◽  
Alina Bączkiewicz ◽  
Patrycja Gonera
Keyword(s):  
Genetic Variation ◽  
North America ◽  
Genetic Distance ◽  
Gene Diversity ◽  
Oil Bodies ◽  
Genetic Studies ◽  
Isozyme Loci ◽  
The Mean ◽  
Different Parts ◽  
Nei's Genetic Distance

Abstract Calypogeia azurea, a widespread, subboreal-montane liverwort species, is one of a few representatives of the Calypogeia genus that are characterized by the occurrence of blue oil bodies. The aim of the study was to investigate the genetic variation and population structure of C. azurea originating from different parts of its distribution range (Europe and North America). Plants of C. azurea were compared with C. peruviana, another Calypogeia species with blue oil bodies. In general, 339 gametophytes from 15 populations of C. azurea were examined. Total gene diversity (HT) estimated on the basis of nine isozyme loci of C. azurea at the species level was 0.201. The mean Nei’s genetic distance between European populations was equal to 0.083, whereas the mean genetic distance between populations originating from Europe and North America was 0.413. The analysis of molecular variance (AMOVA) showed that 69% of C. azurea genetic variation was distributed among regions (Europe and North America), 15% - among populations within regions, and 16% - within populations. Our study revealed that C. azurea showed genetic diversity within its geographic distribution. All examined samples classified as C. azurea differed in respect of isozyme patterns from C. peruviana.

scholarly journals Genetic status of Norway spruce (Picea abies) breeding populations for northern Sweden

2013 ◽  
Vol 62 (1-6) ◽  
pp. 127-136 ◽  
Author(s):  
P. Androsiuk ◽  
A. Shimono ◽  
J. Westin ◽  
D. Lindgren ◽  
A. Fries ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Norway Spruce ◽  
Population Differentiation ◽  
Distinct Group ◽  
Null Alleles ◽  
Multilocus Genotype ◽  
Northern Sweden ◽  
High Genetic Diversity ◽  
Breeding Populations ◽  
Ssr Loci

AbstractEfficient use of any breeding resources requires a good understanding of the genetic value of the founder breeding materials for predicting the gain and diversity in future generations. This study evaluates the distribution of genetic variation and level of relatedness among and within nine breeding populations of Norway spruce for Northern Sweden using nuclear microsatellite markers. A sample set of 456 individuals selected from 140 stands were genotyped with 15 SSR loci. Over all loci each individual was identified with unique multilocus genotype. High genetic diversity (average He=0.820) and low population differentiation (FST=0.0087) characterized this material. Although low in FST, the two northernmost populations were clustered as a distinct group diverged from the central populations. The population differentiation pattern corresponds well with the post glacial migration history of Norway spruce and the current gene flow and human activity in the region. The average inbreeding coefficient was 0.084 after removal loci with high frequency of null alleles. The estimated relatedness of the trees gathered in the breeding populations was very low (average kinship coefficient 0.0077) and not structured. The high genetic variation and low and not structured relatedness between individuals found in the breeding populations confirm that the Norway spruce breeding stock for northern Sweden represent valuable genetic resources for both long-term breeding and conservation programs.

scholarly journals Mercury and Stable Isotopes in Feathers Of Audouin's Gulls as Indicators of Feeding Habits and Migratory Connectivity

The Condor ◽  
2007 ◽  
Vol 109 (2) ◽  
pp. 268-275 ◽  
Author(s):  
Carola Sanpera ◽  
Xavier Ruiz ◽  
Rocío Moreno ◽  
Lluís Jover ◽  
Susan Waldron
Keyword(s):  
Trophic Ecology ◽  
Feeding Habits ◽  
Geographical Area ◽  
Future Research ◽  
Migratory Connectivity ◽  
Migration Patterns ◽  
Isotopic Signatures ◽  
Breeding Populations ◽  
Breeding Grounds ◽  
Wintering Areas

Abstract To better understand migratory connectivity between breeding and nonbreeding populations, we analyzed mercury (Hg) and stable isotope signatures of nitrogen (δ15N), carbon (δ13C), and sulfur (δ34S) in Audouin's Gulls (Larus audouinii) breeding in two different colonies, the Ebro Delta (northeastern Spain) and the Chafarinas Islands (southwestern Mediterranean). Although abundant information is available on the biology and trophic ecology of this gull's breeding populations, little is known about migration patterns, distribution in winter, or conditions faced during the nonbreeding period. Analyses were carried out on first primary feathers, grown during the summer while gulls are on the breeding grounds, and mantle feathers, grown during the winter. Different isotopic signatures (δ15N, δ13C, and δ34S) in summer (primary) feathers from each area agree with the observed differences in diet between the two colonies. In winter (mantle) feathers, isotopic signatures did not differ, consistent with a common wintering ground and common diet, although the lack of isotopic basemaps in marine systems precludes assignment to a geographical area of reference. Future research is needed to relate isotopic signatures and Hg values in mantle feathers to trophic ecology in wintering areas. Results for Hg indicate that the excretory role played by primary feathers precludes their use as indicators of trophic ecology.

The Loggerhead Turtle, Caretta-Caretta, in Queensland - Population Breeding Structure

1988 ◽  
Vol 15 (2) ◽  
pp. 197 ◽  
Author(s):  
E Gyuris ◽  
CJ Limpus
Keyword(s):  
Genetic Variation ◽  
Life History ◽  
Loggerhead Turtle ◽  
Caretta Caretta ◽  
Breeding Population ◽  
Barrier Reef ◽  
Breeding Structure ◽  
Marine Park ◽  
Breeding Populations ◽  
Population Breeding

Population models proposed as a result of independent tagging programs of nesting Caretta caretta in Queensland are in disagreement about the size of discrete breeding units. An electrophoretic survey was conducted to assess the relevance of genetic variation as revealed by electrophoresis to the investigation of Caretta caretta population breeding structure. Low level electrophoretic variability (H*L(obs) = 0.016) was found. The geographical distribution of alleles, when compared with tag-recapture data and other aspects of life history, indicated that discrete breeding populations of C. caretta in Queensland are larger than previously thought. C. caretta nesting on the mainland beaches and on the cays of the Capricornia Section of the Great Barrier Reef Marine Park form a panmictic population. The data indicate that those nesting on the Swain Reefs cays do not interbreed with the mainland-Capricornia breeding population.

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