The Cucurbitaceae family constitutes a phylogenetically diverse botanical group encompassing major agricultural models, specifically evaluating major species under investigation such as Cucumis sativus, Citrullus lanatus, and Cucurbita pepo. Despite their global agrarian prominence, the intricate molecular mechanisms orchestrating their chemodiversity and phenotypic plasticity remain underexplored. This investigation deploys a comprehensive metabolomic framework across 20 representative species spanning 15 distinct tribes to resolve their complex metabolic architectures.
Employing advanced analytical methods based on ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), high-resolution profiling successfully delineated the spatial-temporal distribution of specialized secondary metabolites across diverse plant tissues. Two prominent chemical signatures were explicitly identified: first, the localized hyperaccumulation of oxygenated tetracyclic triterpenoids (cucurbitacins B and E), which act as critical phytoanticipins mediating robust biotic stress mitigation; and second, distinct concentration profiles of bioactive flavonoid glycosides governing environmental adaptation across various plant developmental phases. Furthermore, the systematic integration of stoichiometric metabolic modeling mapped network flux dynamics, yielding quantitative predictive insights into secondary metabolite biosynthesis under fluctuating environmental perturbations and elicitor treatments.
These empirical findings significantly advance our fundamental understanding of chemosystematic evolution within Cucurbitaceae and furnish a robust baseline for molecular breeding initiatives. By isolating high-resolution metabolic markers associated with superior nutritional density and heightened stress resilience, this study delivers actionable data for crop improvement, successfully bridging classical phytotaxonomy with predictive metabolic engineering.