title: Metabolic pathways regulated by abscisic acid, salicylic acid and γ-aminobutyric acid in association with improved drought tolerance in creeping bentgrass (Agrostis stolonifera).
abstract: Abscisic acid (ABA), salicylic acid (SA) and γ-aminobutyric acid (GABA) are known to play roles in regulating plant stress responses. This study was conducted to determine metabolites and associated pathways regulated by ABA, SA and GABA that could contribute to drought tolerance in creeping bentgrass (Agrostis stolonifera). Plants were foliar sprayed with ABA (5 μM), GABA (0.5 mM) and SA (10 μM) or water (untreated control) prior to 25 days drought stress in controlled growth chambers. Application of ABA, GABA or SA had similar positive effects on alleviating drought damages, as manifested by the maintenance of lower electrolyte leakage and greater relative water content in leaves of treated plants relative to the untreated control. Metabolic profiling showed that ABA, GABA and SA induced differential metabolic changes under drought stress. ABA mainly promoted the accumulation of organic acids associated with tricarboxylic acid cycle (aconitic acid, succinic acid, lactic acid and malic acid). SA strongly stimulated the accumulation of amino acids (proline, serine, threonine and alanine) and carbohydrates (glucose, mannose, fructose and cellobiose). GABA enhanced the accumulation of amino acids (GABA, glycine, valine, proline, 5-oxoproline, serine, threonine, aspartic acid and glutamic acid) and organic acids (malic acid, lactic acid, gluconic acid, malonic acid and ribonic acid). The enhanced drought tolerance could be mainly due to the enhanced respiration metabolism by ABA, amino acids and carbohydrates involved in osmotic adjustment (OA) and energy metabolism by SA, and amino acid metabolism related to OA and stress-defense secondary metabolism by GABA.
authors: Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China.|Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, 08901, USA.
authors: Zhou
authors: Z
authors: Li
authors: College of Agro-Grassland Science, Nanjing Agricultural University, Nanjing, 210095, China.
authors: Jingjin
authors: J
authors: Yu
authors: Department of Grassland Science, College of Animal Science and Technology, Sichuan Agricultural University, Chengdu, 611130, China.
authors: Yan
authors: Y
authors: Peng
authors: Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ, 08901, USA.
authors: Bingru
authors: B
authors: Huang
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D031703:Agrostis / Q000187:drug effects / Q000502:physiology*; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D053858:Metabolic Networks and Pathways / Q000187:drug effects*; D010937:Plant Growth Regulators / Q000494:pharmacology*; D018515:Plant Leaves / Q000187:drug effects / Q000502:physiology; D020156:Salicylic Acid / Q000494:pharmacology*; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
chemical_list: D010937:Plant Growth Regulators; D005680:gamma-Aminobutyric Acid; D000040:Abscisic Acid; D020156:Salicylic Acid