RAPD analysis of the intraspecific and interspecific variation and phylogenetic relationships of Aegilops L. species with the U genome

Abstract

RAPD analysis was used to study the genetic variation and phylogenetic relationships of polyploid Aegilops species with the U genome. In total, 115 DNA samples of eight polyploid species containing the U genome and the diploid species Ae. umbellulata (U) were examined. Substantial interspecific polymorphism was observed for the majority of the polyploid species with the U genome (interspecific differences, 0.01-0,2; proportion of polymorphic loci, 56.6-88.2%). Aegilops triuncialis was identified as the only alloploid species with low interspecific polymorphism (interspecific differences, 0-0.01, P = 50%) in the U-genome group. The U-genome Aegilops species proved to be separated from other species of the genus. The phylogenetic relationships were established for the U-genome species. The greatest separation within the U-genome group was observed for the US-genome species Ae. kotschyi and Ae. variabilis. The tetraploid species Ae. triaristata and Ae. columnaris, which had the UX genome, and the hexaploid species Ae. recta (UXN) were found to be related to each other and separate from the UM-genome species. A similarity was observed between the U M-genome species Ae. ovata and Ae. biuncialis, which had the UM genome, and the ancestral diploid U-genome species Ae. umbellulata. The UC-genome species Ae. triuncialis was rather separate and slightly similar to the UX-genome species.