TY - JOUR
T1 - Genetic structure of a population sample of apomictic dandelions
AU - Van der Hulst, R.G.M.
AU - Mes, T.H.M.
AU - Falque, M.
AU - Stam, P.
AU - Den Nijs, J.C.M.
AU - Bachmann, K.
N1 - Reporting year: 2003
Metis note: 3160; CTE; PVP; file:///L:/Endnotedatabases/NIOOPUB/pdfs/Pdfs2003/VanderHulst_ea_3160.pdf
PY - 2003
Y1 - 2003
N2 - In Northern Europe, dandelion populations consist solely of triploid or higher polyploid apomicts. Without a regular sexual cycle or lateral gene transmission, a clonal structure is expected for Taraxacum apomicts, although this was not found by compatibility analysis. In this study, we investigate whether this observation could be suported by performing independent tests based on data from hypervariable microsatellite markers as well as more conservative data based on allozymes and matrilinear cpDNA markers. In addition, population genetic methods were used to test departure from panmictic expectations, which is expected for clonal populations. Results indicated that many data sets, again, did not agree with expectations from clonal evolution because only small groups of genotypes exhibit no marker incompatibility. Population genetic analysis revealed that virtually all genotypes, but not individuals, agreed with random segregation and genotypic equilibria. Exceptions were genotypes with rare allozyme alleles or nearly identical microsatellite genotypes. Consequently, a population sample of apomictic dandelions essentially harbours genotypes that resulted from segregation and/or recombination and only a few genotypes that may have differentiated by somatic mutations [KEYWORDS: Taraxacum, apomixis, AFLPs, character incompatibility]
AB - In Northern Europe, dandelion populations consist solely of triploid or higher polyploid apomicts. Without a regular sexual cycle or lateral gene transmission, a clonal structure is expected for Taraxacum apomicts, although this was not found by compatibility analysis. In this study, we investigate whether this observation could be suported by performing independent tests based on data from hypervariable microsatellite markers as well as more conservative data based on allozymes and matrilinear cpDNA markers. In addition, population genetic methods were used to test departure from panmictic expectations, which is expected for clonal populations. Results indicated that many data sets, again, did not agree with expectations from clonal evolution because only small groups of genotypes exhibit no marker incompatibility. Population genetic analysis revealed that virtually all genotypes, but not individuals, agreed with random segregation and genotypic equilibria. Exceptions were genotypes with rare allozyme alleles or nearly identical microsatellite genotypes. Consequently, a population sample of apomictic dandelions essentially harbours genotypes that resulted from segregation and/or recombination and only a few genotypes that may have differentiated by somatic mutations [KEYWORDS: Taraxacum, apomixis, AFLPs, character incompatibility]
KW - NIOO/CTE/PVP
U2 - 10.1038/sj.hdy.6800248
DO - 10.1038/sj.hdy.6800248
M3 - Article
SN - 0018-067X
VL - 90
SP - 326
EP - 335
JO - Heredity
JF - Heredity
IS - 4
ER -