Differential Metabolic Reprogramming in -Primed Seedlings in Response to Infection.

Metabolic changes in sorghum seedlings in response to (NAS-6G6)-induced systemic resistance against crown rot were investigated by means of untargeted ultra-high performance liquid chromatography-high definition mass spectrometry (UHPLC-HDMS). Treatment of seedlings with the plant growth-promoting rhizobacterium at a concentration of 1 × 10 colony forming units mL prior to inoculation with lowered crown rot disease severity significantly at the highest inoculum dose of 1 × 10 spores mL. Intracellular metabolites were subsequently methanol-extracted from treated and untreated sorghum roots, stems and leaves at 1, 4 and 7 days post inoculation (d.p.i.) with . The extracts were analysed on an UHPLC-HDMS platform, and the data chemometrically processed to determine metabolic profiles and signatures related to priming and induced resistance. Significant treatment-related differences in primary and secondary metabolism post inoculation with were observed between -primed versus naïve seedlings. The differential metabolic reprogramming in primed plants comprised of a quicker and/or enhanced upregulation of amino acid-, phytohormone-, phenylpropanoid-, flavonoid- and lipid metabolites in response to inoculation with .