Bulbous barley

Hordeum bulbosum, the bulbous barley, is a perennial grass in the Poaceae family native to southern Europe, northern Africa, the Middle East and Central Asia as far east as Afghanistan, with naturalized populations in parts of the Americas and Australia. It is distinguished within the genus by the swollen, bulbous bases of its stems, which serve as perennating organs and allow regrowth after summer dormancy in Mediterranean climates. The plant forms tufts of erect culms 30 to 100 centimetres tall arising from these basal bulbs. The leaves are linear, flat to involute, 2 to 6 millimetres wide, with short membranous ligules and slightly auriculate sheaths. The inflorescence is a slender, cylindrical, two-rowed spike 5 to 12 centimetres long, with spikelets borne in groups of three at each rachis node; the central spikelet of each triplet is fertile and bears a long, scabrid awn 1 to 4 centimetres long, while the two lateral spikelets are usually reduced and sterile. Hordeum bulbosum has become important to plant breeders since 1970 as a source of disease-resistance genes and for the production of doubled-haploid wheat and barley lines.