Amelioration of postharvest chilling stress by trehalose in pepper

Currently, reduced shelf-life due to several issues including the elevated chance of chilling stress and the faster deterioration of freshly-cut versus whole fruits, long-term storage of freshly-cut pepper fruits at low temperature storage is still dangerous. In the current report, minimization of pepper chilling stress by the use of trehalose was investigated. Membrane permeability, as well as the concentrations of chlorophyll, vitamin C and malondialdehyde (MDA) were analyzed. Antioxidant peroxidase (POD) and catalase (CAT) enzyme activities were measured. Furtherly, the post-harvest cell ultrastructure of pepper was also observed. These results demonstrated that trehalose enhanced the chilling stress resistance in peppers by reducing cell membrane permeability and MDA content. Activities of POD and CAT in trehalose-treated-fruit were considerably higher than control fruit. Chloroplast membrane was relatively integrated, Osmiophilic globules were inhibited and mitochondria kept their characteristic shape and cristae. Cell walls were undisturbed and the layers of cell wall were clear. These results suggested that trehalose increased pepper-fruit cold tolerance by upregulating antioxidant enzymatic activity and reducing ultrastructural damage.