Comparison of physiological and biochemical responses of local and commercial tomato varieties under water stress and rehydration

Water scarcity presents an increasingly urgent challenge with global implications for the production of irrigated vegetables. Among these crops, tomatoes stand out as one of the most widely cultivated. Given their vulnerability to water stress, it is crucial to ensure efficient and sustainable water management for tomato irrigation. This study aims to compare physiological and biochemical parameters among three local and three commercial resilient tomato varieties in response to water stress and rehydration. We subjected tomato plants to either two brief periods of water stress (WE1) or one extended period of water stress (WE2), followed by rehydration. Our results did not reveal significant differences in the response to water stress among the varieties, which could be attributed to their respective origins. Following rehydration, the plants quickly returned to their normal physiological values. An exploration of oxidative stress markers revealed that oxidative damage occurred solely during the second episode of water stress in WE1 plants, or towards the conclusion of the prolonged water stress period in WE2 plants. However, after rehydration, tomato plants returned to normal oxidative parameters values, indicating the absence of irreversible damage. Although the severe water stress did not compromise the viability of the plants, all treatments and varieties exhibited a predictable and substantial growth inhibition. In conclusion, the different tomato varieties studied exhibited similar responses to water stress, primarily characterized by the inhibition of gas exchange processes and heightened oxidative stress. Nonetheless, none of the plants suffered irreversible damage from this stress.