University of Freiburg, Faculty of Biology, Institute for Biology II, Botany / Plant Physiology, Schänzlestr. 1, D-79104 Freiburg, Germany (KG, GLM)
Department of Plant Breeding & Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linné-Weg 10, 50829 Cologne, Germany (KN, EM, WM)
School of Biological Sciences, Plant Molecular Science, Royal Holloway, University of London, Egham, Surrey TW20 0EX, Uk (GLM);
Web: 'The Seed Biology Place' - www.seedbiology.eu
Received 2012; Revised 2012; Accepted 2012
Article first published online: 19 June 2012
Seed dormancy is an important component of plant fitness that causes a delay of germination until the arrival of a favourable growth season. Dormancy is a complex trait that is determined by genetic factors with a substantial environmental influence. Several of the tissues comprising a seed contribute to its final dormancy level. The roles of the plant hormones abscisic acid and gibberellin in the regulation of dormancy and germination have long been recognized. The last decade saw the identification of several additional factors that influence dormancy including dormancy-specific genes, chromatin factors and non-enzymatic processes. This review gives an overview of our present understanding of the mechanisms that control seed dormancy at the molecular level, with an emphasis on new insights. The various regulators that are involved in the induction and release of dormancy, the influence of environmental factors and the conservation of seed dormancy mechanisms between plant species are discussed. Finally, expected future directions in seed dormancy research are considered.
Key words: abscisic acid (ABA);dormancy;gibberellin (GA);germination;reactive oxygen species (ROS);seed maturation
Financial support: Our work is funded by grants from the Deutsche Forschungsgemeinschaft (Grant DFG LE720/7 to GLM and SO691/3-1 and SFB572 to WJJS), which is gratefully acknowledged.