Environmental Factors Influencing Gardner Saltbush Seed Dormancy Alleviation

Abstract

Pregermination treatments applied to seed of Gardner saltbush, [Atriplex gardneri (Moq.) D. Dietr.] were evaluated for alleviation of seed dormancy. Treatments selected simulated conditions the seed might be exposed to in its natural environment, including dry afterripening, scarification, leaching, and cold stratification. Germination response to individual treatments was equal to or higher than nontreated seed. Germination percentage of afterripened seed was increased from 17% for nontreated filled seed to an average of 86% of filled seed by the combined treatments of scarification, leaching, and 4-week stratification. This combination of treatments allowed optimum germination. Response to treatments provided evidence as to the type of dormancy in Gardner saltbush seeds. The levels of germination response to specific treatments appears to be an adaptation to ensure a temporal dispersal of dormancy release and seedling emergence. Pregermination treatments used in this study were relatively easy to apply to the seeds and stimulated germination without potentially damaging the embryo. Thus, they would be useful in revegetation by direct seeding efforts.