Can Solid Matrix Priming With GA3 Break Seed Dormancy in Eastern Gamagrass?

Abstract

Development of methods for breaking seed dormancy in eastern gamagrass (Tripsacum dactyloides, L.) could increase its use. Solid matrix priming, the controlled hydration of seed in a system of solid carrier and water, has been used with some success to enhance germination in warm-season grasses. gibberellic acid (ga3), a known promoter of eastern gamagrass germination, can be added to solid matrix priming systems. In this study, systems were evaluated for conditioning eastern gamagrass seeds using the solid carriers Agro-Lig, MicroCel E, and Vermiculite #5. GA3 was added in 0.01 M concentration solutions to systems with water potentials of -0.4 and -0.6 MPa in Agro-Lig and -0.2 and -0.4 in MicroCel E and Vermiculite #5 and compared with systems with deionized water. Priming seed with GA3 increased germination to 18% compared with 13% without GA3. MicroCel E and Vermiculite #5 were suitable materials for controlled hydration of eastern gamagrass seed. Germination was only 11% in Agro-Lig compared with 16%-19% for MicroCel E and Vermiculite #5. Priming with GA3 does not appear to be as successful at breaking seed dormancy as cold, wet stratification.