Three Clonal Lineages of Phytophthora cinnamomi in Australia Revealed by Microsatellites

The genetic structure of populations of Phytophthora cinnamomi, a pathogen of an enormous variety of woody plants, was investigated using microsatellites. Three intensively sampled disease sites in southwest Australia were analyzed along with a large culture collection of Austra-lian isolates and some isolates from elsewhere in the world. The mutation in the four microsatellite loci analyzed revealed spatial patterns at the disease sites that correlated with the age of the infestation. Only three clonal lineages were identified in Australian populations and these same clonal lineages were present in worldwide populations, where it is suggested that a limited number of clonal lineages have spread in most regions. No evidence for sexual reproduction between these clonal lineages in Australia has been found even though the pathogen has the opportunity. Instead, mitotic recombination is frequent within the clonal lineages. The implications of this are discussed.

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The Significance of Sexual Reproduction on the Genetic Structure of Populations

Population Genetics and Evolution ◽

10.1007/978-3-642-73069-6_22 ◽

1988 ◽

pp. 209-214

Author(s):

J. Tomiuk ◽

K. Wöhrmann

Keyword(s):

Genetic Structure ◽

Sexual Reproduction ◽

Genetic Structure Of Populations

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Population Genetics ofCaenorhabditis elegans: The Paradox of Low Polymorphism in a Widespread Species

Genetics ◽

10.1093/genetics/163.1.147 ◽

2003 ◽

Vol 163 (1) ◽

pp. 147-157 ◽

Cited By ~ 6

Author(s):

Arjun Sivasundar ◽

Jody Hey

Keyword(s):

Genetic Variation ◽

Microsatellite Loci ◽

Population Expansion ◽

Widespread Species ◽

C Elegans ◽

Model Research ◽

The World ◽

Natural Isolates ◽

History Of ◽

Low Levels

AbstractCaenorhabditis elegans has become one of the most widely used model research organisms, yet we have little information on evolutionary processes and recent evolutionary history of this widespread species. We examined patterns of variation at 20 microsatellite loci in a sample of 23 natural isolates of C. elegans from various parts of the world. One-half of the loci were monomorphic among all strains, and overall genetic variation at microsatellite loci was low, relative to most other species. Some population structure was detected, but there was no association between the genetic and geographic distances among different natural isolates. Thus, despite the nearly worldwide occurrence of C. elegans, little evidence was found for local adaptation in strains derived from different parts of the world. The low levels of genetic variation within and among populations suggest that recent colonization and population expansion might have occurred. However, the patterns of variation are not consistent with population expansion. A possible explanation for the observed patterns is the action of background selection to reduce polymorphism, coupled with ongoing gene flow among populations worldwide.

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Genetic Relationships of Cory's Shearwater: Parentage, Mating Assortment, and Geographic Differentiation Revealed by DNA Fingerprinting

The Auk ◽

10.1093/auk/117.3.651 ◽

2000 ◽

Vol 117 (3) ◽

pp. 651-662 ◽

Cited By ~ 1

Author(s):

Corinne Rabouam ◽

Vincent Bretagnolle ◽

Yves Bigot ◽

Georges Periquet

Keyword(s):

Genetic Variation ◽

Genetic Structure ◽

Dna Fingerprinting ◽

Genetic Relatedness ◽

Isolation By Distance ◽

Genetic Relationships ◽

Cory’S Shearwater ◽

Genetic Structure Of Populations ◽

The Social ◽

Calonectris Diomedea

Abstract We used DNA fingerprinting to assess genetic structure of populations in Cory's Shearwater (Calonectris diomedea). We analyzed mates and parent-offspring relationships, as well as the amount and distribution of genetic variation within and among populations, from the level of subcolony to subspecies. We found no evidence of extrapair fertilization, confirming that the genetic breeding system matches the social system that has been observed in the species. Mates were closely related, and the level of genetic relatedness within populations was within the range usually found in inbred populations. In contrast to previous studies based on allozymes and mtDNA polymorphism, DNA fingerprinting using microsatellites revealed consistent levels of genetic differentiation among populations. However, analyzing the two subspecies separately revealed that the pattern of genetic variation among populations did not support the model of isolation by distance. Natal dispersal, as well as historic and/or demographic events, probably contributed to shape the genetic structure of populations in the species.

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The influence of land use on the genetic structure of populations of the common frog Rana temporaria

Biological Conservation ◽

10.1016/0006-3207(90)90054-s ◽

1990 ◽

Vol 54 (3) ◽

pp. 239-249 ◽

Cited By ~ 131

Author(s):

W. Reh ◽

A. Seitz

Keyword(s):

Land Use ◽

Genetic Structure ◽

Rana Temporaria ◽

Common Frog ◽

Genetic Structure Of Populations ◽

Frog Rana Temporaria ◽

The Common

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The Complex Genetic Structure of Sugarcane Limits Identification of Additional SNP-Defined Simplex Alleles in Microsatellite Loci

Tropical Plant Biology ◽

10.1007/s12042-009-9035-4 ◽

2009 ◽

Vol 2 (3-4) ◽

pp. 133-142 ◽

Cited By ~ 1

Author(s):

Cathrine Lynne McIntyre ◽

Mayling Goode ◽

Thea Monks ◽

Graham D. Bonnett

Keyword(s):

Genetic Structure ◽

Microsatellite Loci

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The genetic structure of populations of Chuckotka Peninsula Eskimos and Chuckchi based on the study of 13 loci of serum and erythrocyte proteins and enzymes

American Journal of Physical Anthropology ◽

10.1002/ajpa.1330790109 ◽

1989 ◽

Vol 79 (1) ◽

pp. 81-88

Author(s):

Ariadna F. Nazarova

Keyword(s):

Genetic Structure ◽

Genetic Structure Of Populations

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The spatial genetic structure of bank vole (Myodes glareolus) and yellow-necked mouse (Apodemus flavicollis) populations: The effect of distance and habitat barriers

Animal Biology ◽

10.1163/157075609x437691 ◽

2009 ◽

Vol 59 (2) ◽

pp. 169-187 ◽

Cited By ~ 19

Author(s):

Michal Kozakiewicz ◽

Alicja Gryczyńska–Siemiątkowska ◽

Hanna Panagiotopoulou ◽

Anna Kozakiewicz ◽

Robert Rutkowski ◽

...

Keyword(s):

Genetic Diversity ◽

Genetic Structure ◽

Bank Vole ◽

Microsatellite Loci ◽

Myodes Glareolus ◽

Apodemus Flavicollis ◽

Island Populations ◽

Local Populations ◽

Bank Vole Myodes Glareolus ◽

Yellow Necked Mouse

AbstractHabitat barriers are considered to be an important factor causing the local reduction of genetic diversity by dividing a population into smaller sections and preventing gene flow between them. However, the “barrier effect” might be different in the case of different species. The effect of geographic distance and water barriers on the genetic structure of populations of two common rodent species – the yellow-necked mouse (Apodemus flavicollis) and the bank vole (Myodes glareolus) living in the area of a lake (on its islands and on two opposite shores) was investigated with the use of microsatellite fragment analysis. The two studied species are characterised by similar habitat requirements, but differ with regard to the socio-spatial structure of the population, individual mobility, capability to cross environmental barriers, and other factors. Trapping was performed for two years in spring and autumn in north-eastern Poland (21°E, 53°N). A total of 160 yellow-necked mouse individuals (7 microsatellite loci) and 346 bank vole individuals (9 microsatellite loci) were analysed. The results of the differentiation analyses (FST and RST) have shown that both the barrier which is formed by a ca. 300 m wide belt of water (between the island and the mainland) and the actual distance of approximately 10 km in continuous populations are sufficient to create genetic differentiation within both species. The differences between local populations living on opposite lake shores are the smallest; differences between any one of them and the island populations are more distinct. All of the genetic diversity indices (the mean number of alleles, mean allelic richness, as well as the observed and expected heterozygosity) of the local populations from the lakeshores were significantly higher than of the small island populations of these two species separated by the water barrier. The more profound “isolation effect” in the case of the island populations of the bank vole, in comparison to the yellow-necked mouse populations, seems to result not only from the lower mobility of the bank vole species, but may also be attributed to other differences in the animals' behaviour.

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