Effect of Different Osmotica on Germination of Alkali Sacaton (Sporobolus airoides Torr.) at Various Moisture Stresses

The moisture-limiting ability of aqueous solutions of mannitol, Carbowax 200, and Carbowax 4,000 was tested at moisture tensions ranging from 0.3 through 15.0 atm. Carbowax 4,000 was the only osmoticum that reduced seed germination at 3.0 atm over that at 0.3 atm. Germination of seeds treated with Carbowax 200 was less at 8.0, 12.0, and 15.0 atm than that of seeds treated with mannitol and Carbowax 4,000, but there were no differences in germination of seeds treated with the latter two osmotica at these tensions. There were no differences in percent germination among any of the osmotica at 0.3 and 3.0 atm.