Date of this Version
Seed Technology 2008, v. 30, no. 1.
Aged switchgrass seed lots can display various levels of dormancy. Under-standing the causes for this dormancy will provide better insight into seed physiology, and potentially lead to treatments that reduce variability in seed germination assays. The effects of sodium nitroprusside, potassium ferro-cyanide and hydrogen peroxide on the germination of eight aged switch-grass (Panicum virgatum L.) seed lots, seven of which were produced in the same year at a single experiment station, were examined. Seed germination demonstrated a significant seed lots × days and treatments × days effect. However, responses of individual seed lots to specific chemicals varied considerably. Genetically related seed lots did not display similar responses to the treatments, while switchgrass derived from a different germplasm exhibited a more similar response. Coleoptile emergence was significantly improved by chemical treatments and showed a significant seed lots × treatment interaction. Together, these results indicate (1) chemicals releasing re-active nitrogen species or peroxide can overcome residual dormancy and stimulate seed germination and coleoptile emergence in diverse switchgrassseed lots, and (2) multiple mechanisms, to some extent under genetic control, appear to direct switchgrass seed germination.