A comprehensive meta-analysis exploring potential of GABA for postharvest chilling injury mitigation in horticultural produce

Abstract

γ-Aminobutyric acid (GABA) exhibits anti-chilling properties and significantly mitigates chilling stress in horticultural products. While numerous studies have explored the effects of GABA on fruits, vegetables, and flowers, uncertainties persist regarding the optimal GABA application method, concentration, and dipping duration for suppressing chilling injury (CI) symptoms. To address this gap, we conducted a comprehensive global meta-analysis comprising 157 evaluations from 19 research papers to assess the impact of GABA on horticultural goods. Our study revealed an overall substantial reduction in CI (-51.1 %) with GABA application compared to the control group. Furthermore, all relevant markers associated with the GABA shunt pathway, oxidative stress, antioxidant system (enzymatic and non-enzymatic), and lipid oxidation with the CI mechanism exhibited significance, except for GABA-En. Interestingly, dipping emerged as a more effective GABA application. Regarding horticultural commodities, GABA was found more effective in fruits (-54.65 %) followed by vegetables (-45.46 %) and flowers (-31.30 %). The regression analysis revealed that GABA concentrations exceeding 1 mM, 5 mM, and 15 mM were ineffective in mitigating CI in flowers, vegetables, and fruits, respectively. These results highlight the efficacy of the GABA dipping and dipping time, as well as, the precise GABA concentration in alleviating CI in flowers, vegetables, and fruits.