Intrapopulation genome size dynamics in Festuca pallens

ŠMARDA, Petr, Petr BUREŠ, Lucie HOROVÁ and Olga ROTREKLOVÁ. Intrapopulation genome size dynamics in Festuca pallens. Annals of Botany. Oxford: Oxford University Press, 2008, vol. 102, No 4, p. 599-607, 8 pp. ISSN 0305-7364.

Basic information

• Original name: Intrapopulation genome size dynamics in Festuca pallens
• Name in Czech: Vnitropopulační dynamika velikosti genomu u Festuca pallens
• Authors: ŠMARDA, Petr (203 Czech Republic, guarantor), Petr BUREŠ (203 Czech Republic), Lucie HOROVÁ (203 Czech Republic) and Olga ROTREKLOVÁ (203 Czech Republic).
• Edition: Annals of Botany, Oxford, Oxford University Press, 2008, 0305-7364.

Other information

• Original language: English
• Type of outcome: Article in a journal
• Field of Study: 10600 1.6 Biological sciences
• Country of publisher: United Kingdom of Great Britain and Northern Ireland
• Confidentiality degree: is not subject to a state or trade secret
• WWW: odkaz na komentář k článku ve vybraném obsahu časopisu odkaz na článek na stránkách časopisu
• Impact factor: Impact factor: 2.755
• RIV identification code: RIV/00216224:14310/08:00024952
• Organization unit: Faculty of Science
• UT WoS: 000259326300012
• Keywords in English: Nuclear DNA content; intraspecific variation; genome size evolution; heritability; stabilizing selection; grasses; flow cytometry
• Tags: flow cytometry, genome size evolution, grasses, heritability, intraspecific variation, nuclear DNA content, stabilizing selection
• Tags: International impact, Reviewed

Abstract

Background and Aims: It is well known that genome size differs among species. However, information on the variation and dynamics of genome size in wild populations and on the early phase of genome size divergence between taxa is currently lacking. Genome size dynamics, heritability and phenotype effects are analysed here in a wild population of Festuca pallens (Poaceae). Methods: Genome size was measured using flow cytometry with DAPI dye in 562 seedlings from 17 maternal plants varying in genome size. The repeatability of genome size measurements was verified at different seasons through the use of different standards and with propidium iodide dye; the range of variation observed was tested via analysis of double-peaks. Additionally, chromosome counts were made in selected seedlings. Key Results and Conclusions: Analysis of double-peaks showed that genome size varied up to 1.188-fold within all 562 seedlings, 1.119-fold within the progeny of a single maternal plant and 1.117-fold in seedlings from grains of a single inflorescence. Generally, genome sizes of seedlings and their mothers were highly correlated. However, in maternal plants with both larger and smaller genomes, genome sizes of seedlings were shifted towards the population median. This was probably due to the frequency of available paternal genomes (pollen grains) in the population. There was a stabilizing selection on genome size during the development of seedlings into adults, which may be important for stabilizing genome size within species. Furthermore, a positive correlation was found between genome size and the development rate of seedlings. A larger genome may therefore provide a competitive advantage, perhaps explaining the higher proportion of plants with larger genomes in the population studied. The reason for the observed variation may be the recent induction of genome size variation, e.g. by activity of retrotransposons, which may be preserved in the long term by the segregation of homeologous chromosomes of different sizes during gametogenesis.

Abstract (in Czech)

Background and Aims: It is well known that genome size differs among species. However, information on the variation and dynamics of genome size in wild populations and on the early phase of genome size divergence between taxa is currently lacking. Genome size dynamics, heritability and phenotype effects are analysed here in a wild population of Festuca pallens (Poaceae). Methods: Genome size was measured using flow cytometry with DAPI dye in 562 seedlings from 17 maternal plants varying in genome size. The repeatability of genome size measurements was verified at different seasons through the use of different standards and with propidium iodide dye; the range of variation observed was tested via analysis of double-peaks. Additionally, chromosome counts were made in selected seedlings. Key Results and Conclusions: Analysis of double-peaks showed that genome size varied up to 1.188-fold within all 562 seedlings, 1.119-fold within the progeny of a single maternal plant and 1.117-fold in seedlings from grains of a single inflorescence. Generally, genome sizes of seedlings and their mothers were highly correlated. However, in maternal plants with both larger and smaller genomes, genome sizes of seedlings were shifted towards the population median. This was probably due to the frequency of available paternal genomes (pollen grains) in the population. There was a stabilizing selection on genome size during the development of seedlings into adults, which may be important for stabilizing genome size within species. Furthermore, a positive correlation was found between genome size and the development rate of seedlings. A larger genome may therefore provide a competitive advantage, perhaps explaining the higher proportion of plants with larger genomes in the population studied. The reason for the observed variation may be the recent induction of genome size variation, e.g. by activity of retrotransposons, which may be preserved in the long term by the segregation of homeologous chromosomes of different sizes during gametogenesis.

Links

• GP206/08/P222, research and development project: Name: Evoluce GC obsahu a genomu trav

Investor: Czech Science Foundation, GC content and genome evolution of grasses

• LC06073, research and development project: Name: Centrum pro výzkum biodiverzity

Investor: Ministry of Education, Youth and Sports of the CR, Biodiversity Research Center

• MSM0021622416, plan (intention): Name: Diverzita biotických společenstev a populací: kauzální analýza variability v prostoru a čase

Investor: Ministry of Education, Youth and Sports of the CR, Diversity of Biotic Communities and Populations: Causal Analysis of variation in space and time