Trade-Off Between Fruit Yield and Antioxidant Accumulation in Physalis peruviana L. Under Different Water Availability Regimes

Physalis peruviana L., a South American species, has been increasingly cultivated because of its bioactive compounds and high commercial value. This study evaluated the biochemical responses and fruit quality of physalis plants subjected to different water availability regimes (40%, 70%, and 100% of field capacity), followed by recovery periods. The experiment was conducted at São Paulo State University in a randomized block design with split plots. Plants were exposed to different irrigation regimes and subsequently rewatered over a 120-day period. Leaf and fruit analyses showed that water stress at 40% field capacity significantly increased both enzymatic and non-enzymatic antioxidant levels, thereby mitigating oxidative damage, as indicated by lower lipid peroxidation and reduced reactive oxygen species accumulation. However, this defense response was accompanied by marked reductions in fruit yield, fruit number, fresh mass, and fruit quality. Notably, although rewatering reversed several biochemical stress markers at the leaf level, fruit yield and commercial quality did not recover, suggesting irreversible damage to reproductive development during the stress period. These findings indicate that controlled water deficit may enhance antioxidant accumulation, highlighting the potential of stressed plants for pharmaceutical or nutraceutical applications. However, prolonged water stress, even when followed by a recovery period, impairs commercial fruit production. Therefore, irrigation management should be aligned with the intended production objective.