Gamma-radiation Induced Modulation of Physical and Defence Enzymatic Dynamics in Post-harvest Tomato

Tomato is a world-wide important agricultural crop which is prone to damage due to high water content and also for various biotic and abiotic stress. Gamma-radiation can be a sustainable method to compensate all the stress and improve its overall shelf-life. It can enhance tomato fruits’ post-harvest shelf-life through enhancement of defence enzymes like Polyphenol oxidase (PPO), Peroxidase (PO), Phenylalanine ammonia-lyase (PAL), overall improvement of Phenol, Flavonoid content, reduction in fungal infection severity and also by reducing weight loss percentage, decay percentage, improving fruit quality. The objective of the experiment to investigate the effects of gamma irradiation on postharvest quality and shelf life of tomato ( Solanum lycopersicum L.). Tomatoes of the local cultivar Pusa Rubi were exposed to different doses of gamma radiation (80 Gy, 100 Gy and 120 Gy) and observed for a storage period of 7 days, 14 days and 21 days. Biochemical, physiological and pathological parameters including phenolic and flavonoid content, defence enzyme activities (PAL, PO, PPO), reactive oxygen species (ROS), hydrogen peroxide (H ₂ O ₂ ) accumulation, weight loss, decay percentage, and resistance to Alternaria solani infection were measured. Based on the experiments, the most effective treatment was the 120 Gy dose. This level notably improved the tomatoes' natural defences against fungal attacks and reduced overall waste. The experiment concluded with the outcome that using gamma irradiation at 120 Gy is a promising method for keeping tomatoes fresh longer while preserving their quality after harvest.