γ-aminobutyric acid (GABA) treatment improves disease resistance and preserves fresh-cut Mesembryanthemum crystallinum L

Abstract

Postharvest diseases significantly affect the quality of fresh-cut Mesembryanthemum crystallinum L. γ-aminobutyric acid (GABA) is a non-protein amino acid that plays a crucial role in the plant's disease resistance process as an endogenous metabolic product and signaling molecule. This study found that exogenous treatment of ice plant with GABA has a positive effect on inhibiting postharvest diseases by regulating the activity of antioxidant enzymes and activating the reactive oxygen species (ROS) pathway, thereby protecting cells from oxidative damage. Concurrently, the addition of exogenous GABA activates the salicylic acid pathway and promotes the biosynthesis of phenylpropanoids, thus enhancing the plant's defense against pathogenic microorganisms. This research proves that GABA could be used as a green preservative to limit postharvest disease losses in fresh-cut ice plants caused by Fusarium sp.