Abstract: To explore the effect of calcium chloride treatment on the postharvest quality of green bell peppers with mechanical damage, bell pepper fruit were dropped from a high place to simulate mechanical damage that may occur during transportation and immersed in 1 mmol/L calcium chloride solution. The hardness, color and sensory quality of bell peppers were determined during storage. Meanwhile, transcriptomic analysis was conducted by high-throughput sequencing technology. Experimental results indicated that 1 mmol/L calcium chloride treatment could significantly delay the reddening, softening and decay of green bell peppers, and the color and texture changes and flavor and aroma-related genes were determined. In addition, the key enzymes and transcription factors involved in the plant hormone signal transduction pathway were identified, and the effect of calcium chloride treatment on the storage quality of green bell peppers with mechanical damage was evaluated. Calcium chloride may occur through the inhibition of the bifunctional 15-cis-octahydrolycopene synthase (PSY) and capsaicin/capsaicin synthase (CCS) and other genes to inhibit carotenoid synthesis, by the inhibition of cellulose synthase A (Ces), endo-1,3-β-glucosidase (β-Glu) and endoglucanase 25 (EG25) to alleviate their softening, and influencing the expression of certain transcription factors, phytohormones and aroma flavor related genes in pepper to improve the apparent quality of green round pepper fruit with mechanical damage. Conclusion: Calcium chloride treatment can effectively delay the deterioration of the fruit quality of the green round pepper, and prolong the storage period of the fruit.

Key words: green bell peppers; transcription; genes; quality; storage