Efeito do pó de rocha na produção de mudas de mimosa Caesalpiniifolia Benth. para restauração florestal

Abstract

The production of native species seedlings is fundamental to the success of forest restoration programs. In this context, soil remineralizers, also known as rock dust, have emerged as a sustainable alternative for seedling production, with potential to reduce dependence on conventional fertilizers. This study aimed to evaluate the effect of different proportions of rock dust and incubation periods in the formulation of substrates for the production of Mimosa caesalpiniifolia Benth. seedlings. The experiment was conducted in a completely randomized design, with statistical analyses performed separately for each incubation period (22 and 36 days), evaluating four substrate formulations: a control treatment consisting of soil and conventional substrate (1:1) and three treatments containing 5, 10, and 20% rock dust (syenogranite and granodiorite — BTGRAN). Seedlings were evaluated at 180 days after sowing. The chemical attributes of the substrates and the morphological characteristics of the seedlings were assessed, including shoot height, stem diameter, number of leaf pairs, shoot dry mass, and root dry mass. The incorporation of rock dust was associated with higher values of phosphorus (P), potassium (K), calcium (Ca), and base saturation (V%) in the substrates compared to the control treatment, with numerically higher values recorded in the treatments incubated for 22 days. However, no statistically significant differences were observed in the growth and quality of Mimosa caesalpiniifolia Benth. seedlings as a function of the rock dust proportions evaluated, in either incubation period. It is considered that the experimental period may have been insufficient to detect the effects of the remineralizer on seedling growth, given the gradual nutrient release characteristic of silicate-based remineralizers. Further studies with longer incubation and seedling evaluation periods are recommended.