Sleeping but not defenceless: seed dormancy and protection

• Published in: Journal of experimental botany 2024-10, Vol.75 (19), p.6110-6124
• Main Authors: Hubert, Benjamin, Leprince, Olivier, Buitink, Julia
• Format: Article
• Language: English
• Subjects: Ecology, environment; Life Sciences; Plant Dormancy - physiology; Plant Growth Regulators - metabolism; Plant Growth Regulators - physiology; Plant Proteins - genetics; Plant Proteins - metabolism; Review Papers; Seeds - growth & development; Seeds - physiology; Signal Transduction; Vegetal Biology
• ISSN: 0022-0957; 1460-2431; 1460-2431
• DOI: 10.1093/jxb/erae213

Abstract To ensure their vital role in disseminating the species, dormant seeds have developed adaptive strategies to protect themselves against pathogens and predators. This is orchestrated through the synthesis of an array of constitutive defences that are put in place in a developmentally regulated manner, which are the focus of this review. We summarize the defence activity and the nature of the molecules coming from the exudate of imbibing seeds that leak into their vicinity, also referred to as the spermosphere. As a second layer of protection, the dual role of the seed coat will be discussed; as a physical barrier and a multi-layered reservoir of defence compounds that are synthesized during seed development. Since imbibed dormant seeds can persist in the soil for extensive periods, we address the question of whether during this time a constitutively regulated defence programme is switched on to provide further protection, via the well-defined pathogenesis-related (PR) protein family. In addition, we review the hormonal and signalling pathways that might be involved in the interplay between dormancy and defence and point out questions that need further attention. In the soil, dormant seeds must cope with pathogens to ensure their persistence. Here we review different defence strategies that dormant seeds rely on to allow their persistence until germination.