Reutilização de cama de aviário compostada na produção e no crescimento inicial de mudas de eucalipto

Abstract

Poultry production is of great prominence in Brazil, generating numerous direct and indirect jobs. Despite its economic importance, it is an activity that produces large amounts of waste, such as poultry litter, a material that if not treated properly can negatively impact the environment by contaminating the soil and water resources. With this work, the objective was to obtain a substrate with composted poultry litter in order to offer an alternative option of environmentally sustainable fertilizer for the production and initial growth of Eucalyptus camaldulensis seedlings. Poultry litter with different numbers of lots of birds housed were composted and characterized in terms of macronutrient content (N, P and K) for use in the two experimental trials: seed germination and initial growth of Eucalyptus camaldulensis seedlings. The seeds were planted in tubes filled with commercial substrate and different percentages of composted poultry litter (20%, 50% and 100%), with a commercial substrate based on pine bark and vermiculite as control treatment. Eucalyptus camaldulensis seedlings were acquired from a commercial nursery and transplanted into 8dm³ pots. The pots were filled with cerrado soil and composted poultry litter in order to provide 100% and 200% of the recommended nitrogen dose for the crop (25 g N/plant), with pots filled with cerrado soil and mineral fertilization in order to provide 25g of N/plant. In the setup of the experiment of initial growth of the seedlings, the Entirely Randomized Design (DIC) was used with the treatments distributed in a 4x2x17 factorial scheme, being 4 treatments, 2 doses of nitrogen and time. The composted poultry litter presented higher nitrogen contents the greater the number of lots of birds housed on the same litter. The seeds had late germination for the treatments with poultry litter in the proportions of 20% and 50% and the seedlings did not survive. In treatments with 100% with poultry litter there was no germination. The best treatment for the biometric characteristic of plant height was composted poultry litter with the highest number of reuses and with 100% of the nitrogen dose. All seedlings showed good indexes of IQD, which indicates that they have great chances of survival in the field.