Operational mechanisms of the plant circadian clock in stress

Abstract

The circadian clock is the internal time-keeping mechanism that anticipates changes in environmental signals in a 24-hour diurnal manner and prepares the plant for synchronization, survival and fitness. Recent research revealed that alterations in components of various hormone and stress-responsive pathways can influence the circadian clock functions and rhythm. Hence, the circadian clock trades off between the growth and defense responses by modulating the robustness or pace of the rhythm through direct or indirect interactions with components of various signaling pathways and networks. Disruptions of the intricate time-keeping processes caused by biotic or abiotic factors can significantly impact plant health. Therefore, it is vital to explore strategies for maintaining plant vitality in the face of such challenges and ensuring the continued functionality of the biological clock. This review discusses contemporary progress in understanding the influence of various unfavorable environmental conditions upon circadian clock function relayed onto the plant responses. It synthesizes current knowledge regarding the responses of clock components to different conditions while identifying areas that remain unexplored. Understanding such processes will allow us to expand the productivity of plants and help us to fortify them against several stressors, particularly in the context of sustainable agriculture and the climate crises.