Efeito da aplicação foliar de diferetes concentrações do Bioestimulante® sobre a propagação clonal de híbridos comerciais Eucalyptus e Corymbia

Abstract

Clonal seedling production plays a fundamental role in Brazilian forestry, with mini-cutting being widely used as a vegetative propagation technique to obtain genetically superior materials. This study aimed to evaluate the effect of foliar application of different concentrations of the commercial biostimulant Stimulate® on rooting, early development, and seedling quality of three commercial hybrids (C1 and C2, Corymbia hybrids; and E3, Eucalyptus hybrid) within the production system of Aperam BioEnergia in Itamarandiba, Minas Gerais, Brazil. The experiment followed a randomized complete block design in a 3 × 4 factorial scheme (three clones and four biostimulant concentrations: 0, 1, 2, and 3 mL L⁻ ¹), with four replications. Rooting, survival, and biometric parameters were evaluated in the greenhouse and hardening stage. Data were subjected to analysis of variance and Tukey's test (p < 0.05). Under the evaluated conditions, foliar application of Stimulate® did not promote expressive changes or additional gains in rooting percentage, root length, or shoot-to-root ratio compared to the control. The effect of biostimulant doses was limited to shoot height, displaying a non-linear response pattern. The genetic factor exerted a predominant influence on most variables: clone E3 achieved superior rooting rates during the hardening stage and greater root system allocation, whereas clone C2 showed higher overall vegetative shoot growth and sensitivity to higher foliar concentrations of the product. It is concluded that foliar application of Stimulate® at the tested doses is not necessary to optimize seedling development, as morphophysiological performance is predominantly determined by the genetic potential of each clone and fully supported by the adopted propagation system.