Giemsa C-banded karyotypes of three subspecies of Taeniatherum caput-medusae and of two intergeneric hybrids with Psathyrostachys spp. (Poaceae)

Abstract

Three subspecies of Taeniatherum caput-medusae (2n=2x=14) had the same karyotype with five pairs of metacentrics, one pair of submetacentrics, and one pair of metacentric SAT-chromosomes with small satellites. The rather similar C-banded karyotypes were characterized by banding patterns with a limited number of mostly small or very small bands randomly distributed. Plants of the same population had identical banding patterns. Banding pattern polymorphism was prevalent, but apparently no larger among than within taxa. The similarity of the C-banded karyotypes supports a close relationship of taxa. Differences in chromosome size and C-banding patterns identified parental genomes in two Taeniatherum×Psathyrostachys hybrids. Psathyrostachys SAT-chromosomes exerted nucleolar dominance. A hierarchy of nucleolar dominance: Hordeum vulgare > P. fragilis > T. caput-medusae is indicated.