Postharvest longevity of perishable produce remains a challenge in the global fresh market supply chain. Postharvest longevity is determined by the rates of ripening and senescence, which are influenced by harvest time and storage conditions. Ripening and senescence are predominantly regulated by ethylene, which produces a plethora of metabolic effects within the harvested produce, leading to physiological and developmental changes during postharvest. Broccoli (Brassica oleracea L. var. italica) are prone to yellowing and wilting due to the relatively high respiration rate and tissue senescence during postharvest handling, transportation, and storage, which greatly affects the quality and reduces market value that led to the problem of food waste and loss. Broccoli florets treated with hydrocooling, 1-MCP (ethylene inhibitor) and controlled atmosphere (CA) can delay the senescence. However, little is known about the mechanisms on how those treatments worked at the molecular level. Here, we combined a physiological, biochemical, and genomics analyses on the postharvest broccoli and identified a core gene regulatory network governing senescence-associated developmental events, ethylene-regulated signaling pathways, and activation of stress responses. Additionally, we developed genome-editing toolkits by CRISPR/Cas9 system to understand deterioration of broccoli as well as through machine learning approaches to aid development of an innovative and easy-to-use accessibility tool to accurately estimate the freshness of produce. The findings give insights into ethylene biosynthesis and signal transduction at the tissue-specific level in broccoli and provide guidance on how to extend broccoli shelf life and reduce its economic losses, which also generate genetics and molecular recourses for marker-assistant breeding and expand the general scientific knowledge of regulating senescence of Brassicaceae family.
