Biotecnologia do uso de água residuária doméstica em solo do cerrado no cultivo do capim Brachiaria brizantha cv Marandu

Abstract

The use of domestic sewage for irrigation of non-food crops, but of zootechnical interest, is a viable alternative for the sustainable use of water resources. The search for agricultural practices that provide high productivity with sustainability of agroecosystems has been a great challenge. So, this study were analyzed the changes in the community of nitrogen fixing bacteria (NFB) and arbuscular mycorrhizal fungi (AMF) by denaturing gradient gel electrophoresis (DGGE) after the use of domestic wastewater to irrigation of Brachiaria brizantha cv Marandu in Cerrado soil. These two microbial groups are the main microorganims indicative of soil fertility. The changes physical and chemical of the soil before and after the use of the fertigation, dry green mass and dry mass productivity and bromatological composition of the grass were analyzed. After the use domestic wastewater of the CEULP/ULBRA in soil to cultivation of B. brizantha cv Marandu, changes in the physical and chemical properties of the soil were observed. The use domestic wastewater did not change the viable microbial cell count. However, the addition of NPK from use domestic wastewater increased the abundance of NFBs and FMAs. The foliar dry mass productivity is highest in the treatments with domestic wastewater and bromatological composition of the grass not was affected by fertigation. Therefore, the NPK concentration added in the soil and the number of cuts contribute to a better nutritional composition of the grass that was cultivated with domestic effluent. Thus, adequate management makes possible the use of fertigation in Cerrado soil for the Marandu grass or other agricultural crop production.