Seedling rescue from natural regeneration and use of Osmocote for production of Jacaranda copaia (Aubl.) D. Don seedlings

Rocha R.N.; Souza W.R.; Coutinho A.D.S.; Milhomem C.A.; Vilhena J.H.S.; Silva L.W.N.; Monteiro Neto J.L.L.; Bardales-Lozano R.M.; Schwartz G.; Dionisio L.F.S. · Brazilian Journal of Biology (2026) · DOI: 10.1590/1519-6984.298048

Resumen

Seedling production of native tree species faces significant challenges, including difficulty in collecting seeds. Jacaranda copaia is a pioneer species with wide distribution in Amazonia, with an important ecological and economic role. This study evaluated the survival rate of J. copaia by the seedling rescue method and the use of different doses of the controlled-release fertilizer Osmocote (15-09-12) on seedling quality. Seedlings from different matrices were rescued from natural regeneration and evaluated for survival 30 days after rescue. To evaluate seedling growth and quality, four doses of Osmocote (0; 1.5; 3.0; 4.5 g plant−1) were tested. The overall survival rate was 84%. The dose of 3.0 g plant−1 of Osmocote was the most efficient, promoting significant increases in the growth of J. copaia seedlings. At 180 days, there was a 113.3% increase in height and 129.9% in stem collar diameter compared to the control. There was also a significant increase in shoot (2.28 ± 0.47 g), root (0.86 ± 0.17 g), and total dry mass (3.14 ± 0.54 g), with balanced relationships between shoot dry mass/root dry mass ratio (3.69 ± 0.64) and higher Dickson quality index (0.54 ± 0.12). The regression models adjusted for all variables showed high coefficients of determination (R2), ranging from 98% to 99%, indicating a strong association between the applied doses and the analyzed parameters. The results show that the use of controlled-release fertilizer is an effective technique to improve the performance of native seedlings, being especially recommended for ecological restoration and reforestation projects.

Instituciones: Universidad Nacional de la Amazonía Peruana