Format

Send to

Choose Destination
Plant J. 2014 Apr;78(2):227-40. doi: 10.1111/tpj.12465. Epub 2014 Mar 26.

Targeting novel chemical and constitutive primed metabolites against Plectosphaerella cucumerina.

Author information

1
Metabolic Integration and Cell Signaling Group, Plant Physiology Section, Department of Ciencias Agrarias y del Medio Natural, Universitat Jaume I, Avenida Vicente Sos Baynat, E-12071, Castellón, Spain.

Abstract

Priming is a physiological state for protection of plants against a broad range of pathogens, and is achieved through stimulation of the plant immune system. Various stimuli, such as beneficial microbes and chemical induction, activate defense priming. In the present study, we demonstrate that impairment of the high-affinity nitrate transporter 2.1 (encoded by NRT2.1) enables Arabidopsis to respond more quickly and strongly to Plectosphaerella cucumerina attack, leading to enhanced resistance. The Arabidopsis thaliana mutant lin1 (affected in NRT2.1) is a priming mutant that displays constitutive resistance to this necrotroph, with no associated developmental or growth costs. Chemically induced priming by β-aminobutyric acid treatment, the constitutive priming mutant ocp3 and the constitutive priming present in the lin1 mutant result in a common metabolic profile within the same plant-pathogen interactions. The defense priming significantly affects sugar metabolism, cell-wall remodeling and shikimic acid derivatives levels, and results in specific changes in the amino acid profile and three specific branches of Trp metabolism, particularly accumulation of indole acetic acid, indole-3-carboxaldehyde and camalexin, but not the indolic glucosinolates. Metabolomic analysis facilitated identification of three metabolites in the priming fingerprint: galacturonic acid, indole-3-carboxylic acid and hypoxanthine. Treatment of plants with the latter two metabolites by soil drenching induced resistance against P. cucumerina, demonstrating that these compounds are key components of defense priming against this necrotrophic fungus. Here we demonstrate that indole-3-carboxylic acid induces resistance by promoting papillae deposition and H2 O2 production, and that this is independent of PR1, VSP2 and PDF1.2 priming.

KEYWORDS:

NRT2.1; indole-3-carboxylic acid; metabolomics; ocp3; priming; β-amino butyric acid

PMID:
24506441
DOI:
10.1111/tpj.12465
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center