Preharvest drought and salinity modulate postharvest physiology, quality, and secondary metabolites of tomato fruit during storage

Preharvest abiotic stress affects tomato quality, but its effects during storage remain poorly understood. This study examined how defined preharvest drought, salinity, and combined drought-salinity stress affected postharvest physiology, fruit quality, and secondary metabolites of tomato fruit stored at 6 °C and 16 °C for up to 20 days. Storage at 6 °C reduced weight loss and decay but increased chilling injury and electrolyte leakage during prolonged storage, particularly in fruit exposed to combined drought-salinity stress. In contrast, storage at 16 °C minimized chilling injury but accelerated ripening-related changes, dehydration, and decay. Preharvest drought and salinity altered dry matter, soluble sugars, and the TSS/TA ratio during early to mid-storage, while secondary metabolite responses were storage temperature- and time-dependent. Combined drought-salinity stress was associated with greater physiological vulnerability despite relatively high values for the antioxidant-related parameters assessed during early to mid-storage, particularly at 6 °C, indicating that higher antioxidant-related responses did not necessarily translate into improved storage stability. Preharvest stress had comparatively limited effects on volatile composition, with the most pronounced treatment-related response observed in drought-treated fruit stored at 16 °C. Overall, preharvest stress history shaped postharvest response trajectories, while storage temperature and duration determined the balance between quality retention and physiological deterioration.