Variable Germination Response to Temperature for Different Sources of Winterfat Seed

Abstract

Superior sources of winterfat seed for range revegetation should be sought, but a clearer concept of what constitutes a "superior" type is necessary. Laboratory germination temperature response of seed collected from three sources was determined. Some positive reactions to 5 degrees C prechilling were observed 13-16 weeks after collection. When the same seedlots were subjected to constant temperatures of 5 degrees C, 10 degrees C, and 20 degrees C, seed from plants originating at the lower elevations (Simla, Colorado and Pine Bluffs, Wyoming) germinated best at the lower temperatures, unlike seed collected from a Laramie, Wyoming source. Kinetic studies of germination verified that rates varied among the seedlots, but were not associated with differences during any particular stage of germination. Different temperature responses between seedlots could have practical implications regarding stand establishment.