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.Rod Helianthus se sastoji od 49 vrsta. U ovom radu ispitivane su dve vrste H. giganteus L. i H. maximiliani Sch., koje su rasprostranjene i sakupljene u severnoj Americi. Da bi se utvrdila morfoloska varijabilnost unutar/izmedju ove dve vrste ispitivano je po petnaest populacija od svake vrste. Analizirano je trideset morfoloskih osobina na pet biljaka od svake populacije, koje su gajene u istim uslovima u kolekciji divljih vrsta na Rimskim Sancevima. Tri populacije iz vrste H. giganteus su na osnovu morfoloskih osobina pokazale vecu slicnost sa populacijama iz vrste H. maximiliani, sto mozda ukazuje na postojanje novog intraspecies taksona u vrsti H. giganteus. Da bi se proverila ova hipoteza ispitivana je i molekularna varijabilnost na istim populacijama-vrstama. Izolovana je genomska DNK iz zamrznutih listova navedenih populacija. Za ispitivanje polimorfizma genomske DNK koristeni su markeri za mikrosatelite, za koje je nedavno pokazana dosad najveca molekularna geneticka varijabilnost u rodu Helianthus. Dobijeni rezultati potvrdjuju visok stepen varijabilnosti izmedju ispitivanih populacija, a u radu su uporedjeni dendrogrami dobijeni klaster analizom morfoloskih osobina i molekularnih markera.