The ability of a seed to germinate and establish a plant at the right time of year is of vital importance from an ecological and economical point of view. Due to the fragility of these early growth stages, their swiftness and robustness will impact later developmental stages and crop yield. These traits are modulated by a continuous interaction between the genetic makeup of the plant and the environment from seed production to germination stages. In this review, we have summarized the established knowledge on the control of seed germination from a molecular and a genetic perspective. This serves as a “backbone” to integrate the latest developments in the field. These include the link of germination to events occurring in the mother plant influenced by the environment, the impact of changes in the chromatin landscape, the discovery of new players and new insights related to well-known master regulators. Finally, results from recent studies on hormone transport, signaling, and biophysical and mechanical tissue properties are underscoring the relevance of tissue-specific regulation and the interplay of signals in this crucial developmental process.

Seed germination is a complex trait determined by the interaction of hormonal, metabolic, genetic, and environmental components. Variability of this trait in crops has a big impact on seedling establishment and yield in the field. Classical studies of this trait in crops have focused mainly on the analyses of one level of regulation in the cascade of events leading to seed germination. We have carried out an integrative and extensive approach to deepen our understanding of seed germination in Brassica napus by generating transcriptomic, metabolic, and hormonal data at different stages upon seed imbibition. Deep phenotyping of different seed germination-associated traits in six winter-type B. napus accessions has revealed that seed germination kinetics, in particular seed germination speed, are major contributors to the variability of this trait. Metabolic profiling of these accessions has allowed us to describe a common pattern of metabolic change and to identify the levels of malate and aspartate metabolites as putative metabolic markers to estimate germination performance. Additionally, analysis of seed content of different hormones suggests that hormonal balance between ABA, GA, and IAA at crucial time points during this process might underlie seed germination differences in these accessions. In this study, we have also defined the major transcriptome changes accompanying the germination process in B. napus. Furthermore, we have observed that earlier activation of key germination regulatory genes seems to generate the differences in germination speed observed between accessions in B. napus. Finally, we have found that protein–protein interactions between some of these key regulator are conserved in B. napus, suggesting a shared regulatory network with other plant species. Altogether, our results provide a comprehensive and detailed picture of seed germination dynamics in oilseed rape. This new framework will be extremely valuable not only to evaluate germination performance of B. napus accessions but also to identify key targets for crop improvement in this important process.

Los organismos genéticamente modificados (OGM) constituyen un concepto equívoco y diferencialmente definido por las distintas legislaciones y sensibilidades que está presente en nuestro léxico desde hace más de 30 años. Con un campo semántico tecnológico y amenazador, la modificación genética y los alimentos GM han sido adoptados en diferentes regiones del mundo, aunque la aceptación por parte de los consumidores y la opinión pública ha sido, por lo general, baja. El debate por la seguridad de este tipo de alimentos está todavía abierto y regido por dos posturas predominantes: el principio de equivalencia por un lado, en el que se da un mayor peso al producto y que ha sido adoptado por Estados Unidos y la Administración de Alimentos y Medicamentos (FDA), y el principio de cautela, en el que se da un mayor peso a la tecnología y que ha sido adoptado por la Unión Europea y la Autoridad Europea de Seguridad Alimentaria (EFSA). La comunidad científica hoy día se decanta por el principio de equivalencia, pero al constituir este un debate complejo y multidisciplinar se requiere un método comunicacional que se sitúe más allá del Modelo de Déficit y un debate abierto y racional.