Cedrela fissilis Vell. e Cariniana estrellensis (Raddi) Kuntze sob doses crescentes de fertilização de liberação controlada

Abstract

The use of controlled-release fertilizers (CRF) represents a promising strategy to improve the production of forest seedlings, particularly for native species with high ecological and silvicultural value. This study evaluated the effects of CRF on the morphophysiological performance of Cedrela fissilis Vell. (cedro-rosa) and Cariniana estrellensis (Raddi) Kuntze (jequitibá-branco) under nursery conditions. The experiment was conducted in a greenhouse using a randomized block design in a 2 × 5 factorial scheme, with two CRF types (NPK 16-08-12(+2), with 6- and 9-month release periods) applied at five doses (0, 4, 8, 12, and 16 g L⁻¹). Variables assessed included height, the diameter at the collar, robustness index, dry biomass, leaf area, root traits, and photosynthetic pigments. Data normality was verified using the Shapiro–Wilk test. For normally distributed data, analysis of variance (ANOVA) was performed at a 5% significance level. In case of significant difference, the mean results were compared by means of t-tests and regression analysis using the software SISVAR 5.6. Seedling responses followed a quadratic pattern, with optimal growth observed at intermediate fertilizer doses. The recommended mean application rates (DMAR), based on the average values of maximum technical efficiency (MTE) doses for the main growth parameters, were 15 g L⁻¹ for C. fissilis and 11 g L⁻¹ for C. estrellensis. CRF application significantly improved seedling growth, biomass accumulation and overall quality, in addition to notable gains in uniformity and visual vigor. The differences between the assessed species highlight the need for tailored fertilization recommendations and their importance. It is concluded that CRFs are effective tools for the nutritional management of native forest seedlings, offering productive and functional benefits which enhance nursery efficiency and support the success of ecological restoration programs in Brazil