Echoes of a Stressful Past: Abiotic Stress Memory in Crop Plants towards Enhanced Adaptation

Plants can develop stress memory as a response to various abiotic stresses, but the underlying mechanisms are not yet fully understood. Most of the knowledge concerning the mechanisms of stress memory development and inheritance in plants is primarily based on research in the model plant Arabidopsis. While shared mechanisms exist across plant species, it is crucial to expand our understanding of epigenetic regulation in crops. Stress priming, or prior exposure to mild stress, can enhance a plant’s adaptation to future stress events and the development of stress memory. During stress priming, plants undergo physiological, biochemical, molecular, and epigenetic changes that can be transient or maintained throughout their lifespan, and in some cases, these changes can also be inherited by the offspring. In this review, we present the current state of knowledge on the development of priming-induced stress memory in agronomically important crops towards stress resilience. The most prominent abiotic stresses, namely, heat, cold, salt, drought, and waterlogging, are highlighted in relation to stress cis-/trans-priming and memory development at the intra-, inter-, and transgenerational levels. The cost for developing stress memory in plants along with the duration of these memory imprints and stress memory fading are also discussed. This review is particularly important in the era of climate change, which necessitates the development of agricultural sustainability strategies