Overcoming physiological dormancy in seeds of Triodia (Poaceae) to improve restoration in the arid zone

• DOI: 10.1111/rec.12357
• Publication Date: 2016-04-22T21:59:49Z
• Authors: Todd E. Erickson; Nancy Shackelford; Kingsley W. Dixon; Shane R. Turner; David J. Merritt
• Keywords: Gibberellic acid

Reinstating dominant Triodia grassland communities following disturbance has been a focus of arid land restoration practitioners for decades in Australia. Yet, seed quality and variable germination have seriously hindered the reestablishment potential species to date. This study set out examine diaspore quality, requirements, dormancy seven identify first, then resolve, impediments. Freshly collected florets from all were cleaned ensure that each floret contained viable evaluated their initial capacity. Very low (<10%) indicated presence physiological ( PD ) species. However, was significantly improved (up 57%) with use 0.67 µm karrikinolide KAR 1 ), lesser degree 289 gibberellic acid GA 3 ). When covering structures (i.e. lemma palea) removed, increased up 59%, which further enhanced after exposure 66%) 92%). Optimal temperatures varied 20 35°C specific. Dry after‐ripening DAR −30°C 50% relative humidity [ RH ]) seeds promoted progressive loss over 12–24 months storage most Germination, level, response incubation temperature differed amongst species, experimental units (florets seeds), treatments, stimulants For seeding programs, careful consideration pre‐treatments is necessary improve