Submitted to: Eastern Native Grass Symposium
Publication Type: Abstract Only
Publication Acceptance Date: July 11, 2003
Publication Date: January 1, 2004
Citation: Tischler, C.R., Derner, J.D., Polley, H.W., Johnson, H.B. 2004. An 'Alamo' switchgrass population with reduced seed dormancy. In: Randall, J., Burns, J.C. Proceedings of The Third Eastern Native Grass Symposium, October 1-3, 2002, Chapel Hill, North Carolina. p. 292.
Alamo switchgrass seed often germinate poorly without a stratification pretreatment. This is one of the reasons that Alamo switchgrass is difficult to establish. Positive results with other warm season grass species prompted us to use recurrent selection as a tool to reduce post-harvest seed dormancy in this species. We performed four cycles of recurrent selection, saving early germinating seedlings from freshly-collected bulk harvests. Progeny testing of seed from 163 plants from the fourth cycle of selection identified 24 plants with superior germination, and these plants were established in replicated plots, and resulting seed was tested for germination at alternating and constant temperatures. Seed from each plant demonstrated considerably better germination (under both temperature conditions) than unselected Alamo. There was a very poor correlation between germination under the differing temperature regimes, indicating a requirement for alternating temperatures in addition to a stratification requirement. Our selection protocol has successfully reduced post-harvest seed dormancy in Alamo switchgrass, and the experimental population is being evaluated for field establishment and possible release as a germplasm.