Effect of Different Varieties and Silicon Fertilizer on the Rooting Efficiency and Productivity of Mini-Cuttings and Powdery Mildew Disease of Eucalypt

Considering that silicon (Si) is a nutrient that stands out in the control of fungal diseases and in the increase in productivity of several cultures, this study intend to evaluate its influence on the productivity and severity of mildew in mini-stumps, as well as rooting of eucalyptus mini-cuttings. The experiment was carried out in a randomized block design with four replications in split plot scheme, the first factor related to Silicon doses (0, 0.5, 1.0, 1.5 and 2 mmol L-1) and the second factor related to five clones of Eucalyptus grandis x Eucalyptus urophylla hybrids (I144, I224, 3334, GG100, GG680). The following variables were evaluated: Si content in mini-cuttings, powdery mildew severity and mini-stumps productivity, and rooting of mini-cuttings. The highest absorption of Si was obtained with a dose of 1.22 mmol L-1 (0.14%). There was no influence of the nutrient solution containing Si on the productivity of mini-stumps, powdery mildew severity or rooting of eucalyptus mini-cuttings. Clones GG100 and 3334 presented, respectively, the best and worst results for all evaluated variables.