Effects of foliar biostimulant formulation and dose on fruit development and quality of sweet granadilla (Passiflora ligularis Juss.)
Plant biostimulants represent a promising alternative for improving production efficiency and fruit quality; however, limited information is available regarding their application to sweet granadilla (Passiflora ligularis Juss.). This study evaluated the effects of formulation and dose of two foliar biostimulants on sweet granadilla fruit development and quality under Andean conditions. Crop+Plus and Kelan Complex were applied at 0.0, 1.0, 1.5, and 2.0 mL·L⁻¹ in a randomised complete block design with split plots. Ten fruits were selected from each experimental unit, and their polar and equatorial diameters were measured at 0, 24, and 50 days after the first application. Total soluble solids, individual fruit weight, and weight-based estimated yield were determined at harvest. Greater polar and equatorial diameters were observed when Crop+Plus was applied, with significant effects of time and their interaction. At 50 days, Crop+Plus at 2.0 mL·L⁻¹ produced the largest polar and equatorial diameters, reaching 7.70 and 7.43 cm, respectively. Total soluble solids were affected by formulation and dose, whereas fruit weight was mainly influenced by dose. The most favourable results were obtained with Crop+Plus at 2.0 mL·L⁻¹, which produced 20.90 °Brix, a mean fruit weight of 120.0 g, and an estimated yield of 6,720 kg·ha⁻¹. In conclusion, Crop+Plus exerted the most consistent effects on fruit growth and quality, and 2.0 mL·L⁻¹ was the most promising concentration within the range evaluated.