Seed Germination Ecology of the Cold Desert Annual Isatis violascens (Brassicaceae): Two Levels of Physiological Dormancy and Role of the Pericarp

• DOI: 10.1371/journal.pone.0140983
• Publication Date: 2015-10-29T17:59:34Z
• Authors: Yuan M. Zhou; Juan J. Lu; Dun Y. Tan; Carol C. Baskin; Jerry M. Baskin
• Keywords: Brassicaceae; Gibberellic acid; Stratification (seeds)

The occurrence of various species Brassicaceae with indehiscent fruits in the cold deserts NW China suggests that there are adaptive advantages this trait. We hypothesized pericarp single-seeded silicles Isatis violascens restricts embryo expansion and thus prevents germination for 1 or more years. Thus, our aim was to investigate role seed dormancy species. effects afterripening, treatment gibberellic acid (GA3) stratification on dormancy-break were tested using intact isolated seeds, phenology monitored an experimental garden. has a mechanically inhibiting fresh seeds promotes nondormant but it does not facilitate formation persistent bank. Seeds watered soil began germinate earlier autumn germinated higher percentages than seeds. Sixty-two percent buried by end first spring, only 3% remained nongerminated viable. Twenty twenty-five have nondeep physiological (PD) 75–80% intermediate PD. PD afterripen summer inside if is moist. Afterripening during significantly decreased amount required break presence both cohort may be bet-hedging strategy.