Genome Analysis of Eurasian Elymus thoroldianus, E. melantherus, and E. kokonoricus (Triticeae: Poaceae)

Elymus thoroldianus (Oliver) G. Singh, E. melantherus (Keng) A. Löve, and E. kokonoricus (Keng) A. Löve are short-lived perennial grasses of the tribe Triticeae distributed throughout the upper and middle mountain ranges of central Asia. Analyzer species used to produce interspecific hybrids with the three target taxa were Pseudoroegneria spicata (Pursh) A. Löve (SS), E. lanceolatus (Scribn. & Smith) Gould (SSHH), Psathyrostachys juncea (Fisch.) Nevski (NN), E. batalinii (Krasn) A. Löve (SSYYPP), E. alatavicus (Drob.) Tzvelev (SSYYPP), E. grandiglumis (Keng) A. Löve (SSYYPP), and E. kengii (Tzvelev) A. Löve (SSYYPP). Elymus thoroldianus, E. melantherus, and E. kokonoricus are self-fertile allohexaploids (2n = 42). Analysis of metaphase I pairing configurations in the F1 indicate that E. thoroldianus, E. melantherus, and E. kokonoricus possess the S, Y, and P genomes, with only minor structural rearrangements. Chromosome pairing in interspecific hybrids with the target species and hexaploid accessions of E. batalinii, E. alatavicus, E. kengii, and E. grandiglumis supports the inclusion of E. thoroldianus, E. melantherus, and E. kokonoricus in the genus Elymus section Hyalolepis.