Produção de mudas clonais de eucalipto em espuma fenólica: crescimento inicial e mortalidade

Abstract

Seedling production is one of the crucial points in the forest companies and studies have been carried out to identify the most appropriate method of production. The utilization of phenolic foam in substitution of plastic tube and organic substrate to grow eucalypt clonal cuttings was evaluated. Four experiments were established, two experiments were set up in nurseries (experiments 1 and 2) and two in the field (experiments 3 and 4). All experiments were composed by four treatments: 1 – conventional system – plastic container of 55 cm3 with commercial substrate (pine bark, vermiculite and peat), 2 - small foam (60 cm3), 3 - medium foam (75 cm3) and 4 - large foam (90 cm3). In all experiments the mortality and the root and shot biomass production were evaluated. In the experiment 1, the plants in the small foam presented lower mortality rate (1%) and the conventional system showed the highest mortality rate (15%) and the large foam showed highest value of the shoot biomass. In experiment 2, the mortality rate was 40% for the foam treatments with higher values when compared to the conventional treatment (16%). In the experiment 3, field experiment, was not observed tree mortality or differences in biomass production among the treatments. In the experiment 4, was observed better tree response to water stress of the stocks in foams, probably because their larger volume. The plants in medium and larger foams showed 3% of mortality, while the conventional system had 25% and the shoot biomass production was highest in the larger foam treatment.