Molecular (ISSR, cp DNA, ITS) and morphological study of the genus Tragopogon L. (Asteraceae)

Abstract

Tragopogon is an Old World genus with 150 species. Mediterranean, Middle East, and Eastern Europe are the distribution centers of this genus. This genus has 26 species in Iran, of which 11 are endemic. The morphology studies of 32 species and Molecular studies (ISSR, ITS, cp DNA) of 22 species of the genus Tragopogon were investigated. Despite the anatomical and molecular studies done around the world, the exact classification of this genus is not clear due to the high number of secret species, hybridization, polyploidy, and rapid diversification. The purpose of these studies is to classify, determine interspecific relationship in this genus, and determine the important morphological characteristics in taxon differentiation. We conclude that sections of Rubriflori, Sosnowskya, Chromopappus, Majores, Angustissimi, and Krascheninnikovia introduced by the flora of Iranica are confirmed by our morphometry and molecular studies. Section of Profundisulcati in flora Iranica is confirmed based on morphometry data. The Species of T. jesdianus, T. porphyrocephalus, T. rezaiyensis, and T. Stroterocarpus in the flora of Iranica are not classified in any section which we classified in the Rubriflori section. Cp DNA dendrogram is not useful for classification in this genus and Chloroplast sequences are very similar among Tragopogon species. Therefore, the use of cp DNA markers in the classification of this genus is not recommended. The use of ISSR and ITS molecular markers are useful for classifying the genus Tragopogon.