Coprolites Production of Native Earthworms in Braquiaria Fields Under Biofertilization

Aims: The objective of this study was to evaluate the coprolite production of native earthworms in a pasture with Brachiaria, with and without liquid-enriched biofertilization.

Place and Duration of Study: The experiment was carried out between April of 2014 and August of 2015 at the Centro de Ciências Agrárias da Universidade Federal da Paraíba – UFPB.

Methodology: A randomized complete block experimental design was used, with subdivided plots and four replicates, with a total of 40 plots in a 5x3x2 factorial arrangement, five grass species (Brachiaria brizantha, B. decumbens, B. humidicola, B. ruziziensise e B. brizantha MG5) and three sampling times, with and without liquid-enriched biofertilization. The plot area was composed of 50.0 m2 (10 m x 5 m) with subplots of 0.25 m2 (0.5 m x 0.5 m). Six foliar fertilization were performed in intervals of fifteen days, with three applications in the drought period and three applications in the rainy season. Each application consisted of 5% of biofertilizer (100 mL of biofertilizer diluted in 2 L of water), each plot received 2 L of biofertilizer.

Results: In the dry season there was a significant difference in the means between the fertilization treatments, leading to the absence of fertilization, obtaining a better result, varying of 48, 24% in relation to the treatments that received fertilization, and there was no significant difference between the brachiaria. In the rainy season, it was verified that there was no significant difference in the means between the fertilization treatments, but there was a significant difference between the brachiaria.

Conclusion: The study concludes that earthworm coprolites production is higher under pasture with B. MG5 during the dry season. In the rainy season, production increased under pasture with B. humidicula. Brachiaria fertilized with liquid-enriched biofertilizer provided lower results in the production of biogenic aggregates (earthworm coprolites). Under conditions of the present study, the hypothesis that the effect of the liquid -enriched biofertilizer increases the production of endogeic earthworm coprolites has not been proven.