Influence of temperature regimes and water stress on the germination of three range grasses and its possible ecological significance to a shortgrass prairie.
Abstract
A germination response study using mannitol was conducted in growth chambers. The highest rate of germination in Agropyron smithii (western wheatgrass) was obtained at 24/13 deg C (day/night temperature regime) while in Bouteloua gracilis (blue grama) and Buchloe dactyloides (buffalo grass) the same was recorded at 29.5/18 deg C. Seed germination in buffalo grass, western wheatgrass, and blue grama was delayed at water stress greater than -3, -7 and -11 bars, respectively. A 9-day sequence with water stress less than or equal to -1 bar under a temperature range of 13 deg C to 29.5 deg C was found to be the most suitable period for germination of these species, under field conditions.