Assessment of the genetic variation of chamomile (Matricaria chamomilla L.) populations using phytochemical, morphological and ISSR markers

► In this study, 21 chamomile populations collected from different geographic regions of Iran and two from Italy and Hungary were used. ► In molecular study, most of the Iranian populations were grouped according to their geographical distribution. ► Morphological data revealed relatively high variation among studied populations. ► Hungary population had the highest essential oil yield, whereas among Iranian ones the highest and the lowest essential oil yield belonged to NW and C regions, respectively.