Abiotic stressors, such as drought, heavy metals, and high salinity, are causing huge crop losses worldwide. These abiotic stressors are expected to become more extreme, less predictable, and more widespread in the near future. With the rapidly growing human population and changing global climate conditions, it is critical to prevent global crop losses to meet the increasing demand for food and other crop products. The reactive gaseous signaling molecule nitric oxide (NO) is involved in numerous plant developmental processes as well as plant responses to various abiotic stresses through its interactions with various molecules. Together, these interactions lead to the homeostasis of reactive oxygen species (ROS), proline and glutathione biosynthesis, post-translational modifications such as S-nitrosylation, and modulation of gene and protein expression. Exogenous application of various NO donors positively mitigates the negative effects of various abiotic stressors. In view of the multidimensional role of this signaling molecule, research over the past decade has investigated its potential in alleviating the deleterious effects of various abiotic stressors, particularly in ROS homeostasis. In this review, we highlight the recent molecular and physiological advances that provide insights into the functional role of NO in mediating various abiotic stress responses in plants.

Originally identified as root-derived exudates that trigger the germination of parasitic weed seeds, strigolactones (SLs) were later discovered to be crucial facilitators of plant symbiotic associations with arbuscular mycorrhizal fungi and then found to be a bona fide plant hormone class in 2008. Thereafter, SLs have been revealed as versatile regulators of plant development, regulating processes as diverse as shoot branching, root architecture, leaf senescence, vasculature formation, and stem secondary growth. Beyond these developmental roles, they function as signaling molecules, enabling plants to adapt to and withstand environmental stresses. This review focuses on the evolutionary diversification of SL biosynthesis and perception, emphasizing how pathway specialization, receptor remodeling, hydrolysis, and downstream signaling generate distinct endogenous and interorganismal functions. It details the complex biosynthetic pathway of SLs, highlighting key enzymes that work together to convert carotenoid precursors into the diverse SLs. The review then explores SL signaling mechanisms, emphasizing the receptor DWARF14 and its interactions with downstream components, such as DWARF53 proteins, which influence how plants perceive and respond to SLs. It also examines the evolutionary aspects of SL biosynthesis and signaling, especially their dual roles in promoting plant-microbe symbiosis and regulating hormone activity. This comprehensive update enhances our understanding of SL functions at the molecular and ecological levels. Moreover, the review discusses the relationship between SLs and karrikins, focusing on DWARF14 and the KARRIKIN INSENSITIVE 2 receptor, and explores potential applications of SLs in agriculture to improve crop resilience and yields. This in-depth account of how SLs operate as master regulators in plant life provides insights into both their evolutionary significance and their potential utility in agriculture.