Genome Size Variation among Accessions of Arabidopsis thaliana

Abstract

A closer investigation of the DNA fractions involved in intraspecific genome size differences in this experimentally accessible species may provide information on the factors involved in stability and evolution of genome sizes.

Genome size variation in Chenopodium quinoa (Chenopodiaceae)

“…Similarly, variation of up to 27% has been found among Finnish genotypes of Tanacetum vulgare L. (Keskitalo et al 1998). Considering these findings, the intraspecific variation revealed in C. quinoa (5.9%) should be regarded as limited; however, it is in agreement with the findings of a number of recent studies which showed genome size variation in species with rather small genomes; for example, A. thaliana (Schmuths et al 2004) and Sesleria albicans Kit. ex Schult.…”

“…However, the results are not straightforward and the relationship between intraspecific variation and environment is still not clear (Knight et al 2005). For example, a negative correlation has been observed between genome size and latitude in A. thaliana (Schmuths et al 2004), whereas no such correlation was found in S. albicans (Lysak et al 2000).…”

“…The DNA C-value for a species is the amount of nuclear DNA in the unreplicated haploid genome of a gamete, and it tends to be characteristic of a taxon and quite constant within a species (Swift 1950). However, since the beginning of the 1980s the number of studies showing significant intraspecific variation in genome size has continued to increase and the original view of species-specific constancy has been questioned (Michaelson et al 1991;Reeves et al 1998;Schmuths et al 2004). Numerous studies have shown variation in C-values in many plant species ranging from a few to as high as 32% (for example, in Arabidopsis thaliana (L.) Heynh.…”

“…Numerous studies have shown variation in C-values in many plant species ranging from a few to as high as 32% (for example, in Arabidopsis thaliana (L.) Heynh. and Helianthus annuus L. respectively) (Michaelson et al 1991;Schmuths et al 2004;Doležel and Bartos 2005). In several cases these findings have been rejected on reinvestigation using an improved technical approach (Greilhuber 2005).…”

“…In several cases these findings have been rejected on reinvestigation using an improved technical approach (Greilhuber 2005). However, in recent years there has been an increase in the number of studies using meticulous methodologies showing intraspecific genome size variation (Lysak et al 2000;Schmuths et al 2004). Intraspecific genome size variation has particularly been found among geographically distant populations or among populations growing in contrasting macroclimatic conditions.…”