Ethephon promotes germination of Echinacea angustifolia E. pallida in darkness

Abstract

Seeds from five lots each of Echinacea angustifolia DC and E. pallida (Nutt) Nutt. were germinated in a growth chamber in light (40 μmol·m-2·s-1) or darkness at 25°C for 16 to 20 days after soaking in 1 mM ethephon or water for 10 minutes or moist stratification at 4 - 6 °C for 2 weeks. Either light or ethephon promoted seed germination of E. angustifolia and E. pallida compared with darkness in nine often lots. Ethephon in the dark had similar or greater germination percentages than water with light. Ethephon with light improved germination in three of ten lots compared with ethephon in the dark. The effect of cold, moist stratification compared with darkness varied by seed lot. Five lots of E. purpurea (L.) Moench were tested, however, no treatment differences were measured. The finding that ethethon promoted E. angustifolia and E. pallida seed germination in darkness could be useful in the cultivation of these two species. Chemical name used: 2-chloroethylphosphonic acid (ethephon).