Effect of Sodium and Magnesium Sulfate on Forage Seed Germination

Abstract

Initial screening of plant species for salt tolerance has often been accomplished by recording germination percent in various salt solutions under controlled environmental conditions. The objectives of this study were to: (1) determine the incubation time required to properly evaluate the germination percent of 8 forage species in sodium sulfate (NaSO4) and magnesium sulfate (MgSO4) solutions under controlled conditions; (2) to document the germination percent of the 8 forage species in response to the Na2SO4 and MgSO4 solutions after the required incubation period. The incubation time required to stabilize the germination percent for each species in the salt solutions varied. Alkali sacaton and switchgrass germination percent stabilized after 7 days; fourwing saltbush, little bluestem, red clover, and thickspike wheatgrass required 14 days; and green needlegrass, 21 days. The germination percent of Canby bluegrass increased throughout the 28-day study period. Germination, after the above incubation periods, was enhanced for fourwing saltbush by the Na2 SO4 and MgSO4 treatments. Germination of green needlegrass and red clover was depressed by all salt treatments; and alkali sacaton, little bluestem and switchgrass germination was depressed by the Na2 SO4 treatment. Germination of thickspike wheatgrass and Canby bluegrass (at 28 days) was not affected by any of the salt treatments. Results show the importance of the incubation period used in the initial screening of forage species for salt tolerance. Fourwing saltbush, thickspike wheatgrass, and Canby bluegrass were the least sensitive to the Na2 SO4 and MgSO4 solutions studied.