Reactive oxygen species as architects of redox dynamics and adaptive potential in cereal crops under global climate change. Part I

The article presents current insights into the role of reactive oxygen species (ROS) in regulating the expression of genes responsible for histone modifications in cereal crops under abiotic stress conditions. It is shown that ROS perform not only destructive but also essential sig-naling functions, participating in the maintenance of redox homeostasis and the orchestration of adaptive plant responses. The mechanisms of ROS generation and scavenging are analyzed, along with their involvement in the regulation of transcriptional cascades and their interactions with an-tioxidant and hormonal systems. Special attention is given to the relationship between redox sig-naling and epigenetic modifications, including histone acetylation and methylation, which drive chromatin remodeling and the establishment of stress memory. The work summarizes experimen-tal evidence on redox-epigenetic regulation in wheat and other cereals, demonstrating that ROS-induced epigenetic modifications underlie the flexibility and heritability of adaptive responses. Additionally, the mechanisms of ROS involvement in the coordination of inter-organellar signal-ing and systemic plant responses are discussed. The study emphasizes the significance of ROS as a key integrator linking metabolic, transcriptional, and chromatin-level regulation. The epigenetic network governed by ROS is proposed as a molecular compass guiding plant adaptation to stress and the development of climate-resilient, high-yielding cereal crops. Considering ROS as a central hub of redox regulation opens new perspectives for targeted manipulation of redox-epigenetic mechanisms within breeding and biotechnological strategies aimed at improving plant productiv-ity and stress tolerance under global climate change.