GERMINATION RESPONSE OF TWO ALPINE GRASSES FROM THE ROCKY MOUNTAINS OF ALBERTA

Abstract

Germination studies on alpine bluegress (Poa alpina L.) and broad-glumed wheatgrass (Agropyron latiglume Scribn. and Smith [Rydb.]) were undertaken to determine optimum germination conditions, the presence of seed dormancy and the extent of variability among populations for rapid germination. Poa alpina seeds germinated best under darkness and 16/8 h cycles of 22/15 °C temperature, while A. latiglume needed a 29/22 °C regime and darkness for best germination. Rapid germination in both species occurred within a narrow range of temperature conditions. Light and suboptimal temperatures appeared to have an inhibitory effect on seed germination during the initial period of imbibition. Germination inhibition through external factors (secondary dormancy) and the presence of primary dormancy in the nursery-grown seeds may be a genetic adaptation to stressful alpine environments. This and the differences among populations for seed germination in both species are encouraging for our breeding program which is developing genotypes for alpine and subalpine reclamation.Key words: Alpine bluegrass, broad-glumed wheat grass, temperature effect, light, population, seed germination.