INFLUENCES OF TEMPERATURE, LIGHT AND WATER-STRESS ON GERMINATION OF FRINGED SAGE (ARTEMISIA-FRIGIDA)

Experiments were conducted to determine the influences of temperature, light, winter storage, and water stress on seed germination of fringed sage, Seeds collected in 3 yr in central Saskatchewan were placed in sealed vials and buried in the soil after harvest, and germination was tested in spring and early summer, Seeds germinated over a wide range of temperatures with alternating 25/15 C being optimal, The range of optimal temperatures was higher for older seeds than younger seeds, The stimulating effect of light on germination varied among collections and incubating temperatures, Total germination and germination rate was limited by water stress and no seeds germinated at osmotic potentials below -0.9 MPa. Seeds hydrated in the autumn and exposed to low winter temperatures had higher germination the following spring than dry seeds exposed to the same conditions. Results suggest that sufficient soil moisture combined with moderate seedbed temperatures are optimal for fringed sage germination, Periodicity of germination may be influenced by variable germination requirements in different aging seeds.