Cold plasma treatment enhanced defense responses against gray mold and enhances postharvest quality in cherry tomatoes.

A dielectric barrier discharge (DBD) system was utilized to enhance the postharvest quality and defense responses of cherry tomatoes. Results indicated that Cold Plasma (CP) treatment enhanced both postharvest quality and gray mold resistance in the friut. CP treatment (41.5 kV, 3 min) yielded a maximum increase in the lycopene content of cherry tomatoes by 27.02% relative to the control. Microbial counts were concurrently reduced, by 0.31 log CFU/g for bacteria and 0.36 log CFU/g for fungi. Additionally, CP treatment mitigated weight loss, delayed firmness decline, and slowed the reduction of soluble solids content during storage. Furthermore, CP treatment (31.4 kV, 3.6 min) significantly enhanced gray mold resistance, reducing the lesion diameter by 35% and upregulating the activities of POD, SOD, CAT, APX, PAL, and C4H. These enhanced defense responses were accompanied by changes in cell wall- and respiration-related enzyme activities, evidenced by elevated SDH and CCO activities alongside suppressed PG and Cx activities. These findings provide physiological and biochemical evidence supporting the potential application of CP in the postharvest of tomatoes.