title: β-Aminobutyric acid increases abscisic acid accumulation and desiccation tolerance and decreases water use but fails to improve grain yield in two spring wheat cultivars under soil drying.
abstract: A pot experiment was conducted to investigate the effect of the non-protein amino acid, β-aminobutyric acid (BABA), on the homeostasis between reactive oxygen species (ROS) and antioxidant defence during progressive soil drying, and its relationship with the accumulation of abscisic acid (ABA), water use, grain yield, and desiccation tolerance in two spring wheat (Triticum aestivum L.) cultivars released in different decades and with different yields under drought. Drenching the soil with 100 µM BABA increased drought-induced ABA production, leading to a decrease in the lethal leaf water potential (Ψ) used to measure desiccation tolerance, decreased water use, and increased water use efficiency for grain (WUEG) under moderate water stress. In addition, at severe water stress levels, drenching the soil with BABA reduced ROS production, increased antioxidant enzyme activity, and reduced the oxidative damage to lipid membranes. The data suggest that the addition of BABA triggers ABA accumulation that acts as a non-hydraulic root signal, thereby closing stomata, and reducing water use at moderate stress levels, and also reduces the production of ROS and increases the antioxidant defence enzymes at severe stress levels, thus increasing the desiccation tolerance. However, BABA treatment had no effect on grain yield of wheat when water availability was limited. The results suggest that there are ways of effectively priming the pre-existing defence pathways, in addition to genetic means, to improve the desiccation tolerance and WUEG of wheat.
authors.affiliation: State Key Laboratory of Grassland Agroecosystem, Institute of Arid Agroecology, School of Life Sciences, Lanzhou University Lanzhou 730000, Gansu Province  China.
authors.forename: Yan-Lei
authors.initials: YL
authors.lastname: Du
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Wang
authors.forename: Jing-Wei
authors.initials: JW
authors.lastname: Fan
authors.forename: Neil C
authors.initials: NC
authors.lastname: Turner
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
authors.forename: Feng-Min
authors.initials: FM
authors.lastname: Li
mesh_terms: D000040:Abscisic Acid / Q000032:analysis / Q000378:metabolism*; D000613:Aminobutyrates / Q000494:pharmacology*; D000975:Antioxidants / Q000378:metabolism; D018533:Biomass; D003890:Desiccation; D055864:Droughts; D002523:Edible Grain / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D054046:Plant Stomata / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D018526:Plant Transpiration / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D012987:Soil; D013312:Stress, Physiological / Q000187:drug effects*; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D014867:Water / Q000378:metabolism*
chemical_list: D000613:Aminobutyrates; D000975:Antioxidants; D017382:Reactive Oxygen Species; D012987:Soil; D014867:Water; C047667:3-aminobutyric acid; D000040:Abscisic Acid