Changes in the metabolomic profiling of Allium cepa L. (onion) plants infected with Stemphylium vesicarium

Screening of short-day onions for resistance to Stemphylium leaf blight in the seed-to-bulb stage (stage I) and bulb-to-seed stage (stage II)

“…Also, the higher phenolic acid levels may cause changes in pH of plant cell cytoplasm, which results in the inhibition of pathogen development and ultimately enhance the level of resistance (Ojalvo et al, 1987;Mahmoodi-Khaledi et al, 2015). Medina-Melchor et al (2022) reported that upon infection with S. vesicarium, the concentration of pyruvic acid increased in the bulb, roots, and leaves of onion plants. Likewise, in our study also pyruvic acid in leaf tissue increased from before inoculation and was found maximum at 20 days after inoculation in genotypes having low disease incidence.…”

Twenty Years of 1H NMR Plant Metabolomics: A Way Forward toward Assessment of Plant Metabolites for Constitutive and Inducible Defenses to Biotic Stress

“…The most commonly reported increases were described for alanine 50,91,100 and glutamic acid, 46,91,100 followed by proline, 29 tyrosine, 100 phenylalanine, 100 isoleucine, 100 leucine, 100 and valine. 100 Biotic stress to host plants is known to cause increases in the concentration of certain amino acids in phloem sap or in the amino acid pool in cells. Some amino acids, like tryptophane, tyrosine, phenylalanine, and methionine, serve as precursors for antimicrobial secondary metabolites.…”

“…29 Galactose decreased in the early stage infection of onions with Stemphylium vesicarium. 100 Glucose (but not so fructose and sucrose) responded to bacterial infection by either an increase 57,90,101 or decrease 30,36 in various plants exposed to bacterial infections depending on the species and type of bacteria. For example, phytoplasma infection in Catharanthus roseus has increased leaf sucrose, but this was related to the type of phytoplasma.…”

“…Glucose and sucrose often responded simultaneously in stress conditions. 29,[49][50][51]91,100 Changes were reported in fructose of grapes challenged by the esca disease. 49 Arabinose and xylose increased in the late-stage infection of oil palms with G. boninens.…”

“…Overall, the levels of amino acids show an overall increase in response to fungal infection with some exceptions. The most commonly reported increases were described for alanine ,, and glutamic acid, ,, followed by proline, tyrosine, phenylalanine, isoleucine, leucine, and valine . Biotic stress to host plants is known to cause increases in the concentration of certain amino acids in phloem sap or in the amino acid pool in cells.…”