Reactive oxygen species (ROS) and reactive nitrogen species (RNS) incessantly produced as by-products of metabolism play significant roles in seed physiology. ROS (hydroxyl, superoxide radical and hydrogen peroxide) and RNS (nitric oxide, nitric dioxide, nitrous acid and dinitrogen tetroxide) content changes in all phases of seed life cycle that influence seed germination, dormancy and longevity. Recent studies illustrate that ROS and RNS are performing oxidative and nitrosative signaling to induce seed germination within oxidative window level. Besides, ROS/RNSmediated post-translational modifications (PTM) like carbonylation, S-nitrosylation and nitration are gaining interest in promoting seed germination. Understanding the signalling pathways, cross-talk with plant hormones and their role in promoting seed germination and dormancy alleviation could pave way for hormone engineering that help in crop productivity, particularly under climatic changing conditions. In addition, role of antioxidants and glutathione thiols in protecting from oxidative damage indicate that these compounds can be used for seed viability/ quality markers that aid in monitoring of crop establishment. In this review, sources of ROS and RNS, their cross-talk with plant hormones (prospects for hormone engineering), signalling functions pertaining to seed germination, dormancy and deterioration have been illustrated. In addition, seed quality markers under climatic changing conditions for effective monitoring of crop stand establishment and diagnostics development have been elucidated.