Genome Size Variation inMalusSpecies

摘要

The nuclear DNA content for 256 different accessions belonging to 26 primaryMalusspecies and 20 species hybrids was estimated by flow cytometry using propidium iodide. Diploids ranged from 1.245 (M. tschonoskii) to 1.653  pg per 2C nucleus (M. florentina). As our study covered complete phylogenetic and geographic representation, preliminary conclusions between nuclear DNA content and geographical and taxonomic features could be drawn. The data indicated that species found far from the centre of origin in Asia clustered into separate sections and series and possessed higher DNA content. These areM. trilobataandM. florentinathe only two species existing in South-East Europe on one hand;M. ioensisand 3x and 4x speciesM.×heterophylla, M.×platycarpa, M. glaucescens, M. angustifolia, M. lancifoliaandM. coronaria—in East and Central North America on the other hand. A significantly decreased 1Cx DNA content was observed with the increase in ploidy for six species.