No abstract

Dinizia excelsa is one of the largest trees in the Amazon rainforest, with significant economic potential for the recovery of degraded areas. It is a key species for biodiversity and increased forest biomass. However, studies related to seedling production of this species are still scarce. In this study, we evaluated the production and quality of D. excelsa seedlings in response to the application of controlled-release fertilizer doses. The experimental design was completely randomized, applying different doses of Osmocote® (T1=0; T2=4.1; T3=8.2; and T4=12.3 g.dm-³) with four replicates, using vermiculite and coconut fiber (1:1 v/v) as the substrate. We assessed the number of leaves and leaflets, shoot and root length, stem diameter, seedling height, shoot-to-stem diameter ratio, leaf area, dry mass of shoot, root, and total biomass. The data were subjected to analysis of variance and regression analysis. The seedlings responded positively to the use of Osmocote®, and starting from the 4.1 g.dm-³ dose, biomass accumulation showed better results, making it a recommended practice that allows cost savings in seedling production of this species.