Reactive Oxygen Species in Crop Plants: Production, Detoxification, Signaling, and Molecular Cross-Talk

Although excess generation of reactive oxygen species (ROS) is harmful for plants, at mild concentrations, they are able to positively regulate the metabolic pathway and signaling cascades of the cell. The mechanisms functional under the ROS-induced stress tolerance need to be decoded for the development of new abiotic stress-tolerant crop varieties with a clear vision. This study details ROS generation, roles of enzymatic antioxidants as well as non-enzymatic antioxidants, and ROS-induced cellular events. Emphasis is given to crucial topics such as cyclin-dependent kinases and mitogen-activated protein kinases signaling mechanisms, calcium-mediated cellular cross-talk, and activation or inactivation of various transcription factors. Introduction of different genetic and molecular approaches to manipulate the ROS pathway helps to find out novel recombinant plant varieties. Selection of specific biotechnological tools, appropriate omics analysis and implementation of CRISPR/Cas 9 in crop plants assist the designing of mutants. This review highlights the beneficial roles of oxidative stress, spotlighting the molecular mechanisms that support the physiological, morphological and biochemical modifications of plant cells.