Temperature Profiles for Germination of Two Species of Winterfat

Abstract

Germination of seeds of winterfat [Ceratoides lanata (Pursh) Howell] and Eurasian winterfat [C. latens (J.F. Gnel.) Reveal and Holmgren] was compared at 55 constant and alternating temperatures. The seeds of both species germinated at a wide range of temperatures. Optimum germination (defined as not lower than the maximum and its 0.01 probability confidence interval) occurred most frequently at 0, 2, and 5 degrees C cold period temperatures alternating with 15 and 20 degrees C. Optimum temperature regimes tended to be slightly warmer for seeds of Eurasian winterfat. There were large year-to-year differences in the quality of Eurasian winterfat seeds. Three sources of winterfat purchased from commercial seed dealers had low to very low germinability. Seeds of the Hatch selection of winterfat that we tested had a germination response equal to or better than the commercial sources of winterfat seeds.