EVALUATION OF ACELGA (Beta vulgaris var. Cicla) PRODUCTION USING ORGANIC FERTILIZERS PREPARED BY ANAEROBIC DIGESTION OF COW AND PIG MANURE

Animal manure is a valuable source of nutrients and renewable energy. However, most of the manure is collected in lagoons or left to decompose in the open which pose a significant environmental hazard. Anaerobic digestion is a treatment solution for animal manure, producing biogas and an effluent byproduct, the digestate which is considered as organic fertilizer. In this work we tested the use of the effluent of the anaerobic digestion of cow and pig manure in culture of chard (Beta vulgaris var. Cicla) compared with the use of a chemical products. We prepared two 120 L anaerobic digesters, one feed with cow and other with pig manure at 7% dry solids basis. They were maintained at an average temperature of 25°C during 78 days, the biogas production was monitored. At the end of the anaerobic digestion was determined the phytotoxicity of the liquid fractions of the digestate, and tested their efficiency as a fertilizer in chad crop compared with chemical products. We found that using the effluent from the pig manure anaerobic digestion was obtained the highest crop production (3.7 kg), followed by the chemical fertilizer (3.05 kg), the effluent from cow anaerobic digestion (2 kg) and a phytohormone commercial product (1.4 kg).   besides the root length was lower using the phytohormones commercial product , roots of plant using the other treatments were similar between them. Anaerobic digestion is a good way to reduce contamination by manure and get a substituent of the chemical product for agriculture.