Morphological and molecular variability of Helianthus giganteus L. and Helianthus maximiliani Sch. species

Abstract

Genus Helianthus consists of 49 species. Two species H. giganteus L. and H. maximiliani Sch., distributed and collected in North America, were investigated. In order to determine morphological variability in/between these two species, fifteen populations of each species were used. Thirty traits were measured on five plants per species, grown in the same conditions in the wild species nursery at Rimski Sancevi. According to the investigated morphological traits, three species of H. giganteus were closer to H. maximiliani populations, which possibly indicates the existence of a new intraspecies taxon in H. giganteus. In order to test this hypothesis molecular variability of the same populations-species, was also investigated. The polymorphism of genomic DNA, that was isolated from frozen leaves, was investigated by microsatellites, recently shown to be the most powerful for the analysis of molecular genetic variability in genus Helianthus. Obtained results confirm the high variability between examined populations. Dendrograms constructed by cluster analysis of examined morphological traits and molecular markers are discussed.