Multifaceted functions of strigolactones in annual and perennial plants: developmental regulation, phytohormone crosstalk and abiotic stresses

Strigolactones (SLs) are a class of carotenoid-derived terpenoid lactones. Recent studies have revealed the mechanisms by which endogenous SLs control numerous aspects of plant architecture formation and growth, including shoot branching, root architecture development, and the responses to various environmental stresses such as drought, cold, and low-phosphorus and low-nitrogen levels. As a relatively newly discovered type of plant hormone, SLs are gaining attention for their exceptional development value and application potential in the fields of agricultural science and forestry biology. In this review, we initially summarize the discovery history and structural characteristics of SLs. Then, we introduce the physiological regulatory patterns and molecular regulatory mechanisms of SLs in plant growth and development regulation, abiotic stress adaptation, and the interactions of SLs with other hormones. Finally, we discuss recent advances in SL research in forest trees and outline future research frontiers and emerging techniques involving SLs. Thus, this review provides theoretical guidance and technical support for the physiological and molecular basis of SL use in regulating plant growth and development and offers new perspectives for investigating the genetic regulatory networks of important traits for improved plant breeding via molecular design.