Priming applied to commercial seed lots is widely used by seed technologists to enhance seed vigour in terms of germination potential and increased stress tolerance. Priming can be also valuable to seed bank operators who need improved protocols of ex situ conservation of germplasm collections (crop and native species). Depending on plant species, seed morphology and physiology, different priming treatments can be applied, all of them triggering the so-called 'pre-germinative metabolism'. This physiological process takes place during early seed imbibition and includes the seed repair response (activation of DNA repair pathways and antioxidant mechanisms), essential to preserve genome integrity, ensuring proper germination and seedling development. The review provides an overview of priming technology, describing the range of physical-chemical and biological treatments currently available. Optimised priming protocols can be designed using the 'hydrotime concept' analysis which provides the theoretical bases for assessing the relationship between water potential and germination rate. Despite the efforts so far reported to further improve seed priming, novel ideas and cutting-edge investigations need to be brought into this technological sector of agri-seed industry. Multidisciplinary translational research combining digital, bioinformatic and molecular tools will significantly contribute to expand the range of priming applications to other relevant commercial sectors, e.g. the native seed market.

Physical dormancy (PY) in seeds/fruits, which is caused by the water-impermeable palisade layer, has long been considered a mechanism for synchronizing germination to a favourable time for seedling survival and establishment. Recently, a new hypothesis (crypsis hypothesis) was proposed as the main selective factor for the evolution of PY. However, there are some misconceptions in this hypothesis. Our objective is to critically evaluate the crypsis hypothesis and to point out that there are multiple adaptive roles of PY. The fundamental argument in the crypsis hypothesis, that PY evolved as an escape mechanism from predators, is not valid according to the evolutionary theory of Darwin. According to Darwin's hypothesis, variations (dormancy in our case) within a population occur randomly, i.e. there is no direct function of a variation at the time of its origin. Different selection pressures operating in the environment increase or decrease the fitness of individuals with the variation. Water-gap anatomy in seeds/fruits and phylogenetic relationships of species with PY suggest that PY has evolved several times in angiosperms. Thus, we argue that not only predatory pressure but also several other environmental pressures (e.g. proper timing of germination, ultra-drying of seeds, dispersal and pathogens) were involved in increasing the fitness of species producing seeds with PY. The significance of PY in the survival of the species under the abovementioned environmental pressures and other misconceptions of the crypsis hypothesis are discussed in detail.

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Understanding the key aspects of plant regeneration from seeds is crucial in assessing species assembly to their habitats. However, the regenerative traits of seed dormancy and germination are underrepresented in this context. In the alpine zone, the large species and microhabitat diversity provide an ideal context to assess habitat‐related regenerative strategies. To this end, seeds of 53 species growing in alpine siliceous and calcareous habitats (6230 and 6170 of EU Directive 92/43, respectively) were exposed to different temperature treatments under controlled laboratory conditions. Germination strategies in each habitat were identified by clustering with k‐means. Then, phylogenetic least squares correlations (PGLS) were fitted to assess germination and dormancy differences between species’ main habitat (calcareous and siliceous), microhabitat (grasslands, heaths, rocky, and species with no specific microhabitats), and chorology (arctic–alpine and continental). Calcareous and siliceous grasslands significantly differ in their germination behaviour with a slow, mostly overwinter germination and high germination under all conditions, respectively. Species with high overwinter germination occurs mostly in heaths and have an arctic–alpine distribution. Meanwhile, species with low or high germinability in general inhabit in grasslands or have no specific microhabitat (they belong to generalist), respectively. Alpine species use different germination strategies depending on habitat provenance, species’ main microhabitat, and chorotype. Such differences may reflect adaptations to local environmental conditions and highlight the functional role of germination and dormancy in community ecology.

Mangroves are highly adapted to extreme environmental conditions that occur at the interface of salt and fresh water. Adaptations to the saline environment during germination are a key to mangrove survival, and thereby, its distribution. The main objective of this research was to study the effect of salinity on seed germination of selected mangrove species and the application of a hydrotime model to explain the relationship between water potential of the medium and rate of seed germination. Germination of seeds was examined at 15, 25 and 35°C in light/dark over a NaCl gradient. Germination time courses were prepared, and germination data were used to investigate whether these species behave according to the principles of the hydrotime model. The model was fitted for the germination of Acanthus ilicifolius seeds at 25°C. Final germination percentage was significantly influenced by species, osmotic potential and their interaction at 25°C. Moreover, temperature had a clear effect on seed germination (Sonneratia caseolaris and Pemphis acidula) which interacted with osmotic potential. Only A. ilicifolius seeds behaved according to the hydrotime principles and thus its threshold water potential was –1.8 MPa. Optimum germination rates for seeds of the other species occurred at osmotic potentials other than 0 MPa. The descending order of salinity tolerance of the tested species was Aegiceras corniculatum > Sonneratia caseolaris > Acanthus ilicifolius > Pemphis acidula > Allophylus cobbe, suggesting that the viviparous species (A. corniculatum) is highly salt tolerant compared with the non-viviparous species. The results revealed that seeds of the study species exhibited facultative halophytic behaviour in which they can germinate over a broad range of saline environments. Use of a hydrotime model for mangroves was limited as germination of their seeds did not meet model criteria.