Constitutive gibberellin response in grafted tomato modulates root-to-shoot signaling under drought stress

Author(s)

Gaion, Lucas Aparecido ^[1] ; Monteiro, Carolina Cristina ^[1] ; Rodrigues Cruz, Flavio Jose ^[1] ; Rossatto, Davi Rodrigo ^[1] ; Lopez-Diaz, Isabel ^[2] ; Carrera, Esther ^[2] ; Lima, Joni Esrom ^[3] ; Pereira Peres, Lazaro Eustaquio ^[4] ; Carvalho, Rogerio Falleiros ^[1]

Affiliation

^[1] Sao Paulo State Univ, Dept Biol Appl Agr, Via Acesso Prof Paulo Donato Castellane, BR-14884900 Jaboticabal - Brazil

^[2] CSIC UPV, Inst Plant Mol & Cellular Biol IBMCP, Carrer Enginyer Fausto Elio, Valencia 46011 - Spain

^[3] Univ Fed Minas Gerais, Inst Biol Sci, Bot Dept, Avea Presidente Antonio Carlos, 6627, Belo Horizonte, MG - Brazil

^[4] Univ Sao Paulo, Dept Biol Sci, Ave Padua Dias, BR-13418900 Piracicaba - Brazil

• Document type: Journal article
• Source: Journal of Plant Physiology; v. 221, p. 11-21, FEB 2018.
• Web of Science Citations: 6

Abstract

Plants are sessile organisms that must perceive and respond to various environmental constraints throughout their life cycle. Among these constraints, drought stress has become the main limiting factor to crop production around the world. Water deprivation is perceived primarily by the roots, which efficiently signal the shoot to trigger drought responses in order to maximize a plant's ability to survive. In this study, the tomato (Solanum lycopersicum L.) mutant procera (pro), with a constitutive response to gibberellin (GA), and its near isogenic line cv. Micro-Tom (MT), were used in reciprocal grafting under well-watered and water stress conditions to evaluate the role of GA signaling in root-to-shoot communication during drought stress. Growth, oxidative stress, gene expression, water relations and hormonal content were measured in order to provide insights into GA-mediated adjustments to water stress. All graft combinations with pro (i.e. pro/pro, MT/pro and pro/MT) prevented the reduction of growth under stress conditions without a reduction in oxidative stress. The increase of oxidative stress was followed by upregulation of SlDREB2, a drought-tolerance related gene, in all drought-stressed plants. Scions harboring the pro mutation tended to increase the abscisic acid (ABA) content, independent of the rootstock. Moreover, the GA sensitivity of the rootstock modulated stomatal conductance and water use efficiency under drought stress, indicating GA and ABA crosstalk in the adjustment of growth and water economy. (AU)

• FAPESP's process: 14/19165-2 - Using of a mutant in gibberellin in grafting of the tomato to study signaling this hormone between roots and shoots during water deficit
• Grantee: Lucas Aparecido Gaion
• Support Opportunities: Scholarships in Brazil - Doctorate