The role of dormancy, temperature and light in the regulation of seed germination of four annual Asteraceae from south-western Australia was investigated. The experiments aimed to identify after-ripening patterns, and to relate these to climatic conditions of the habitat in which the species occur. Seeds of all species were strongly dormant at maturity and maintained high levels of dormancy for...

The physiological dormancy of sunflower (Helianthus annuus) embryos can be overcome during dry storage (after-ripening) or by applying exogenous ethylene or hydrogen cyanide (HCN) during imbibition. The aim of this work was to provide a comprehensive model, based on oxidative signaling by reactive oxygen species (ROS), for explaining the cellular mode of action of HCN in dormancy alleviation. B...

seed dormancy is a temporary failure of a viable seed to germinate. various methods are used for breaking seed dormancy, depending on plant species and type of dormancy. three seed populations originated from esfahan, semnan and fars provinces were exposed to different seed dormancy breaking treatments such as mechanical and chemical scarification, humid chilling, ga3 and polyethylenglycol 6000...

seed dormancy has a critical role in ecological adaptation of wild plant species such as hordeum spontaneum, a wild relative of barley. in this study, 192 ecotypes of hordeum spontaneum maintained in national plant gene bank of iran (npgbi) originating from different climatic zones of the country were evaluated. morphological, phenological and physiological traits were recorded in the field. af...

After-ripening is the mechanism by which dormant seeds become nondormant during their dry storage after harvest. The absence of free water in mature seeds does not allow detectable metabolism; thus, the processes associated with dormancy release under these conditions are largely unknown. We show here that sunflower (Helianthus annuus) seed alleviation of dormancy during after-ripening is assoc...

The changes in germination potential of freshly harvested seeds of Arabidopsis thaliana stored in various combinations of temperature and relative humidity were investigated over 63 weeks of storage. Seeds of the wild type Col-0 and of two mutants displaying low and high levels of dormancy, cat2-1 and mtr4-1, respectively, were stored at harvest in 24 different environments including a combinat...

BACKGROUND AND AIMS Seed yield and dormancy status are key components of species fitness that are influenced by the maternal environment, in particular temperature. Responses to environmental conditions can differ between ecotypes of the same species. Therefore, to investigate the effect of maternal environment on seed production, this study compared two contrasting Arabidopsis thaliana ecotype...

Kent J. Bradford Department of Vegetable Crops, One Shields Avenue, University of California, Davis, CA 956168631, U.S.A. E-mail: [email protected] Knowledge and prediction of seasonal weed seedling emergence patterns is useful in weed management programs. Seed dormancy is a major factor influencing the timing of seedling emergence, and once dormancy is broken, environmental conditions det...