Biogeography of Lycium L. (Solanaceae) and Phylogeny of Old world Taxa Based on Sequences of nrDNA (ITS) and cpDNA (trnL-F)

More than 100 species of genus Lycium, in family Solanaceae, subfamily Solanoideae and tribe Lycieae are distributed in the arid and semi-arid regions of the world. Phylogenetic and biogeographic studies have mostly been based on South and North American species and some other species in old world. In this research for determining phylogeny of Old world taxa and biogeographic relationships between Old and New world taxa, Iranian species have been studied beside the most of species in New and Old world based on the two genes tmL-F (from chloroplast) and ITS (from nucleus). The results based on the sequencing of these regions indicated that in contrast to some previous reports, the Old world species were polyphyletic group. Genus Lycium appeared in new world (Southern American) and then they were transferred to Southern Africa and from that place were distributed to Eurasia. They were transferred from Southern Africa and Eurasia to Australia. According to this investigation, it can be concluded that Australia is the end area of Lycium dispersal.