Calcium (Ca2+) signaling in plants: A plant stress perspective

Calcium ions (Ca2+) serve as ubiquitous signaling molecules and are involved in diverse biological processes, particularly pivotal in plant growth and stress response. When plants sense environmental changes, an initial response involves an intracellular shift in free Ca2+ levels, with the spatiotemporal characteristics influenced by the nature, intensity, and duration of the stimulus. Decoding and relaying these changes into biological processes require the utilization of Ca2+ sensors. Abiotic stresses impact plant physiology and development by causing environmental fluctuations beyond optimal ranges. Abiotic stressors encompass suboptimal temperature, osmotic disturbances, hazardous ions, and nutrient deficiency. Recognizing and transducing signals in response to these stressors involve multiple components and methods due to their complexity. Additionally, plants contend with biotic factors, triggering calcium signaling cascades. However, understanding of gene functions related to managing specific transient calcium signals during particular stresses is limited. This review delves into the emerging conceptual implications of Ca2+ signaling in plant abiotic stress responses at both intracellular and extracellular levels. It also explores the potential influence of Ca2+ signaling on various agricultural stresses in future research directions.