Title Effects of Antioxidant Treatments on Sprouting, Survival, Callus Formation, and Attempted Adventitious Rooting of Campomanesia adamantium Cuttings Across Different Seasons

Gabiroba (Campomanesia adamantium (Cambess.) O. Berg) is a native fruit tree of the Brazilian Cerrado biome with notable economic potential and phytotherapeutic properties. However, commercial seedling production is limited by the recalcitrant nature of its seeds and vegetative propagation is further constrained by phenolic compound oxidation. Therefore, this study evaluated the effects of antioxidant treatments on sprouting, cutting survival, callus formation and attempted adventitious rooting of C. adamantium cuttings collected in different seasons. The experiment was conducted in a greenhouse at the Federal University of Jataí using cuttings collected from an experimental orchard. Eleven treatments were evaluated: a control and different concentrations of ascorbic acid (AA; 10, 20, and 40 mg L−1), phloroglucinol (FLO; 50, 100, and 200 mg L−1), and polyvinylpyrrolidone (PVP; 100, 200, 400, and 600 mg L−1). After 60 days, sprouting, cutting survival, callus formation, rooting, and the number of old and new leaves were assessed. Data were subjected to analysis of variance, and means were compared using the Scott–Knott test. Antioxidant treatments did not promote rhizogenesis in C. adamantium cuttings. Nevertheless, the season influenced sprouting, survival, and callus formation, especially during summer and autumn. These results indicate that antioxidant application alone is insufficient to overcome rooting recalcitrance in this species, although it may affect early developmental responses of the cuttings under specific seasonal conditions.