Exploring ripening suppression in peach fruit during controlled atmosphere storage with transcriptome insights

This study evaluated the effectiveness of controlled atmosphere (CA) storage in preserving the post-harvest quality of peaches (Prunus persica), focusing on delaying ripening and extending shelf life. Peaches harvested 110 days after bloom were stored under CA conditions with reduced oxygen and elevated carbon dioxide at low temperatures. CA storage significantly suppressed internal and external discoloration, maintained fruit firmness, and reduced ethylene production, contributing to prolonged freshness and marketability. Physiological assessments revealed that CA storage slowed the decline in firmness, minimized weight loss, and controlled respiration and ethylene production, particularly at 10 °C. Transcriptome analysis identified approximately 1971 differentially expressed genes associated with CA storage. Among these, ethylene biosynthesis and signaling genes such as ACC synthase 1, ACC synthase 6, and ACC oxidase 1 were significantly downregulated under CA conditions, leading to the suppression of ethylene production. This reduction in ethylene biosynthesis likely played a critical role in delaying the ripening process during storage. As a result of the suppressed ethylene signaling, the expression of key cell wall-degrading enzymes, including polygalacturonase and pectate lyase family, was also notably reduced. This downregulation contributed to the maintenance of fruit firmness by minimizing enzymatic degradation of the cell wall. CA storage also modulates the activity of reactive oxygen species-related enzymes, enhancing fruit resistance to oxidative stress. These findings highlight the targeted benefits of CA storage in extending the shelf life of peaches by delaying ripening, maintaining fruit firmness, and reducing spoilage. This approach offers a scientifically supported strategy to minimize post-harvest losses and enhance economic returns in the horticultural industry.