XVI International Botanical Congess

The genus Nolana (Solanaceae) consisting of 80 species is distributed in the Pacific coastal region in South America and isolated in Galapagos Islands. The Nolana are main components of the lomas in the deserts. This study aims to examine the evolution of Nolana in the deserts.The species in Peru are herbs with large flat leaves while those in Chile are shrubs with small terete leaves. The putative CAM plants were recognized by higher values of delta 13C in Atacama Desert. The molecular phylogenetic tree by the sequences of the ITS region of nrDNA suggests that N. galapagensis was separated at the earliest stage of the evolution of the genus. Successive speciation occurred firstly in Peruvian Desert then in Atacama Desert. Divergence time of the Nolana from the closest sister taxa was estimated to be middle Miocene.