Avaliação do Biofertilizante Supermagro na Produção de mudas de Eucalyptus dunnii Maiden

Abstract

The quantity and quality of seedling production is one of the most important steps for the establishment of forest population. This work aimed to evaluate the quality of Eucalyptus dunnii Maiden seedling produced using the Supermagro® biofertilizer and its economic viability; Specific objectives: Evaluate the quality of seedlings of Eucalyptus dunnii produced with the Supermagro® biofertilizer; Identify the best recommendation (concentration versus application interval) of Supermagro® biofertilizer by seedlings of Eucalyptus dunnii. Compare the fertilization costs with Supermagro® with the conventional chemistry fertilization. Two separated experiments were conducted in August and September 2010, in the greenhouse of the Forest Nursery M & M Florestal, located in Palmas, State of Paraná. The experiments were conducted in completely randomized design. Ten treatments and four replications were performed. In the first one, there were 80 seedlings per plot and 40 in second one. In both experiments, it was first evaluated the influence of chemical fertilizer and three different concentrations of Supermagro®, applied at intervals of 14 days in seedlings of Eucalyptus dunnii. Subsequently, it was evaluated the interaction of three concentrations of Supermagro® with three different time application range. With the completion of this study, it was concluded that seedlings fertilized with biofertilizer Supermagro® at concentrations less than or equal to 5% did not reach the average height and diameter to meet the quality standards recommended. However, seedlings fertilized with Supermagro® at concentrations of 10, 15 or 20% applied at intervals of 14 days, meet the recommended standards of height and diameter, although these were lower than those of seedlings that received chemical fertilization. These results suggest that the concentrations of 10, 15 or 20% Supermagro® applied at intervals of 7, 14 or 28 days could be used as an alternative to chemical fertilizers, since the Dickson quality index was not affected by these concentrations of Supermagro®, and the biofertilizer gives better results when applied in 14 or 28 days intervals. Treatment with Supermagro® 10% applied every 28 days showed the lowest cost (R$ 0.3 cents per seedling).