Connected phytohormone biosynthesis pathways at the core of growth-stress tradeoffs

Abstract

How plants experiencing environmental stress regulate their growth to survive is a fundamental question crucial for future food security. Drought and high salinity both represent osmotic stresses that severely decrease crop yields worldwide. Understanding how plants cope with these stresses becomes increasingly critical as the world faces a rapid deterioration of arable land. Plants respond to stress by activating stress-avoidance or stress-tolerance pathways, reprogramming gene regulatory networks, and increasing protective solutes (reviewed in Claeys and Inzé, 2013 Claeys H. Inzé D. The agony of choice: how plants balance growth and survival under water-limiting conditions. . 2013; 162: 1768-1779https://doi.org/10.1104/pp.113.220921 Google Scholar ; Zhang et al., 2020 Zhang H. Zhao Y. Zhu J.K. Thriving under stress: How plants balance growth and the stress response. Dev. Cell. 2020; 55: 529-543https://doi.org/10.1016/j.devcel.2020.10.012 Abstract Full Text Full Text PDF PubMed Scopus (80) Google Scholar ). A primary outcome of increasing stress tolerance is reduced growth, creating an essential tradeoff between growth and stress tolerance—plants must carefully manage this tradeoff to survive the stress and maintain competitiveness. Recently, a study by Liu et al., 2022 Liu W.C. Song R.F. Zheng S.Q. Li T.T. Zhang B.L. Gao X. Lu Y.T. Coordination of plant growth and abiotic stress responses by tryptophan synthase β subunit 1 through modulation of tryptophan and ABA homeostasis in Arabidopsis. Mol. Plant. 2022; https://doi.org/10.1016/j.molp.2022.04.009 Abstract Full Text Full Text PDF Scopus (11) Google Scholar demonstrated a new mechanism in which these tradeoffs are achieved.