Basalt rock dust incorporated to substrate favors Monteverdia ilicifolia seedlings initial growth

This study aims to analyze the incorporation of basalt rock dust to a commercial substrate based on pine bark under two light conditions on initial growth of Monteverdia ilicifolia (Mart. Ex Reissek) Biral seedlings. We evaluated four proportions of rock dust: 0% (control), 10%, 20%, and 30% on plants kept unshaded and under 50% shading for 140 days. The unshaded condition associated with basalt rock dust incorporated to substrate presented the higher seedlings growth. Incorporating rock dust in any proportion to the substrate increased stem diameter and biomass, resulting in a greater Dickson quality index (DQI) in unshaded seedlings. The rock dust in a proportion of 10% showed better results in seedlings growth. Moreover, 20% and 30% of rock dust reduced stem diameter, biomass, and DQI, when compared to 10% of rock dust, possibly due to the substrate physical characteristics. We recommend incorporating 10% of rock dust to the pine bark-based substrate for M. ilicifolia seedlings production in an unshaded environment.