Cytology and taxonomy of Elymus kengii, E. grandiglumis, E. alatavicus, and E. batalinii (Poaceae: Triticeae)

Abstract

Elymus alatavicus (Drob.) A. Löve, E. batalinii (Krasn.) A. Löve, E. kengii (Keng) Tzvelev, and E. grandiglumis (Keng) A. Löve are rare hexaploid perennial grasses of the tribe Triticeae native to central Asia. This paper further describes the (i) genomic makeup of E. batalinii and E. alatavicus; (ii) chromosome pairing and fertility in hybrids between E. alatavicus or E. batalinii and E. kengii or E. grandiglumis; (iii) morphological variation among the taxa; and (iv) necessary taxonomic changes within Elymus necessitated by the above studies. On the basis of chromosome pairing in the hybrids E. batalinii × E. dentatus (Hook. f.) Tzvelev ssp. ugamicus (Drob.) Tzvelev, 10.21 I + 12.11 II + 0.18 III + 0.01 IV, and E. alatavicus × Pseudoroegneria tauri (Boiss. &Bal.) A. Löve, 13.10 I + 10.05 II + 0.52 III + 0.08 IV, the genomic formula for E. batalinii and E. alatavicus can be written as SSYYPP. Chromosome pairing in the hybrids E. alatavicus × E. grandiglumis, 9.37 I + 16.23 II + 0.06 III; E. kengii × E. batalinii, 10.25 I + 15.54 II + 0.21 III + 0.02 IV; and E. grandiglumis × E. batalinii, 9.15 I + 13.47 II + 1.09 III + 0.06 IV, combined with species morphology, supports the grouping of the above taxa in Elymus L. section Hyalolepis (Nevski) A. Löve rather than being separated in Elymus section Goulardia (Husnot) Tzvelev.Key words: genome, meiosis, chromosome pairing, interspecific hybrids, Elymus, Triticeae.