The objective of this study was to quantify the microbial variables and the productivity of bean under different soil managements and limestone application. Part of a site under no-tillage (NT) system for 20 years was submitted to minimum tillage (MT), with limestone incorporation at 0.25 m depth and chisel plowing. The treatments were soil managements (NT and MT) and surface limestone application (0 and 2 t ha-1), with four replicates. Carbon of microbial biomass higher values were found on the MT and CO2 evoluted, on the NT without limestone application. The smallest mycorrhizal colonization and the highest number of spores were observed on the MT without limestone application. No significant differences among treatments were detected for dry matter production. For grain yield, the higher values were found on the MT with limestone application. It is possible to avoid interruptions on the NT by the surface application of limestone, once the incorporation of organic material and limestone induced little changes on the system stability, which was confirmed by the similarity among statistical values for the C-CO2 evoluted and the slight differences for the other variables studied between soil managements.
tillage system; minimum-tillage system; carbon of microbial biomass; CO2 evoluted; arbuscular mycorrhizal fungi; cerrado
