Inter-simple sequence repeats (ISSR) and morphological diversity in Onosma L. (Boraginaceae) species in Iran

Abstract

Morphological characteristics as well as inter-simple sequence repeats (ISSR) molecular markers were used to study the species relationship in Onosma species (Boraginaceae) in Iran. Principal component analysis (PCA) showed that morphological characters like caule leaf size and shape, bract shape, corolla shape, nutlet length, venation and corolla teeth size and anther length are the most variable morphological characters among Onosma species studied. Out of 17 ISSR primers used, 6 primers produced 41 polymorphic and reproducible bands. Few specific ISSR bands were obtained for the species studied which show genetic material change during species diversification. Such bands may be used in the species identification too. Morphological and molecular trees obtained partly agreed with each other. In both trees, Onosma dasytrichum and Onosma microcarpum are placed close to each other, Onosma procerum and Onosma pachypodum show affinity to each other and Onosma araraticum, Onosma bodeanum, Onosma bistonensis, Onosma stenosiphon and  Onosma bulbotrichum are placed close to each other while, Onosma rostellatum stands far from the other species. The combined morphological and ISSR tree obtained separated the members of three sections of Onosma, Podnosma and Protonosma from each other. Moreover, almost a good separation of different subsections in the section Onosma was observed in the combined tree.

Key words: Inter-simple sequence repeats, morphometry, Onosma.