Limited genome size variation in Sesleria albicans

The extent and significance of intraspecific genome size variation in plant s continues to be a matter of discussion: in some species considerable vari ation has been described, while no variation has been detected in other tax a. In the present study, intraspecific genome size variation was analysed i n a perennial grass Sesleria albicans Kit. ex Schult. (Poaceae). Flow cytom etry was used for the analysis of nuclear DNA content in ten geographically isolated populations of S. albicans. Despite long-term isolation and lack of gene-flow between the populations, only negligible inter-population diff erences were found. Although the differences between the populations were s tatistically significant, the maximum inter-population difference reached o nly 1.6 % of the mean 2C value (9.78 +/- 0.04 pg). The variation was not co rrelated with geographical location or with altitude of the populations ana lysed. The present study clearly demonstrates that S. albicans belongs to t he plant taxa with a highly stable genome size. (C) 2000 Annals of Botany C ompany.