Preharvest gibberellic acid4+7 (GA4+7) treatment induces physiological disorders by mediating major metabolites in cold-stored ‘Wonhwang’ pears (Pyrus pyrifolia Nakai)

Abstract

The aim of this study was to evaluate the effectiveness of preharvest gibberellic acid4+7 (GA4+7) treatment on fruit quality attributes, major metabolites, and physiological disorders in cold-stored ‘Wonhwang’ pears. The GA4+7 treatment was applied to the fruit stalk at 35 days after full bloom. Pears were stored at 0.5 °C and 90 % relative humidity for up to six months after harvest and then maintained for one day of shelf life at 22 °C. All physiological variables in preharvest GA4+7 treatment, especially, flesh firmness, soluble solids content, and titratable acidity, were significantly decreased after six months of cold storage. Moreover, the targeted metabolic profile analyses indicated that the contents of major organic acids, besides malic acid, free amino acids, and sorbitol, were lower in GA4+7 treated fruit than in untreated fruit. The preharvest GA4+7 treatment also reduced levels of soluble carbohydrates and organic acids. In addition, the incidence and severity of physiological disorders, such as peel staining, cortex browning, water soaking, and cavity were much more severe in the GA4+7 treated fruit than in untreated fruit. Therefore, the results indicated that preharvest GA4+7 treatment negatively affected certain major metabolites mainly in amino acids and thus aggravated postharvest fruit quality attributes, contributing to the incidence and severity of physiological disorders in cold-stored ‘Wonhwang’ pears. Overall, preharvest GA4+7 treatment negatively affected fruit quality and induced physiological disorders after long-term cold storage. © 2024 Elsevier B.V.