Species delimitation and relationship in Crocus L. (Iridaceae)

Abstract

AbstractThe genusCrocusL. (Iridaceae) is monophyletic and contains about 100 species throughout the world.Crocusspecies have horticultural, medicinal and pharmacological importance. Saffron is the dried styles ofC. sativusand is one of the world’s most expensive spices by weight. Controversy exits about the taxonomy of the genus and the species relationship. Exploring genetic diversity and inter-specific cross-ability are important tasks for conservation of wild taxa and for breeding of cultivatedC. sativus. The present study was performed to study genetic variability and population structure in fiveCrocusL. species includingCrocus almehensisBrickell & Mathew,C. caspiusFischer & Meyer,C. speciosusMarschall von Biberstein,C. haussknechtiiBoissier, andC. sativusL. by inter simple sequence repeat (ISSR) molecular markers. We also used published internal transcribed spacer (ITS) sequences to study species relationship and compare the results with ISSR data. The results revealed a high degree of genetic variability both within and among the studied species. Neighbor joining (NJ) tree and network analysis revealed that ISSR markers are useful inCrocusspecies delimitation. Population fragmentation occurred inC. caspiusandC. sativus. Both ISSR and sequenced based analyses separatedC. sativusfrom the other studied species. Close genetic affinity ofC. sativusandC. pallisiiand inter-specific gene flow was supported by both data sets.