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Surface and subsurface acidity and soil compaction restrict root exploration and impair crop yields in agropastoral systems under no‐till. To support the development of surface and subsurface acidity correction methodologies that can decrease soil compaction in agropastoral systems under no‐till, this study tested the following hypotheses: (a) the incorporation of limestone with plowing and harrowing (conventional tillage) for surface and subsurface acidity correction decreases soil compaction in agropastoral systems under no‐till, (b) the subsurface application of hydrated lime with a shank subsoiler‐fertilizer (minimum tillage) for surface and subsurface acidity correction decreases soil compaction in agropastoral systems under no‐till, and (c) the surface application of Ca compounds (no tillage) for surface and subsurface acidity correction increases soil compaction in agropastoral systems under no‐till. In a field experiment in an agropastoral system under no‐till in an Arenic Hapludalf in Brazil, the abilities of three application management methodologies (no tillage, conventional tillage, and minimum tillage) for three Ca compounds (limestone, phosphogypsum, and hydrated lime) to ameliorate acidity in the surface and subsurface layers and decrease soil compaction were evaluated. The experimental design was a randomized complete block with four replications. The results support the following conclusions: (a) the incorporation of limestone with plowing and harrowing does not decrease soil compaction in agropastoral systems under no‐till; (b) the subsurface application of hydrated lime with a shank subsoiler‐fertilizer does not decrease soil compaction in agropastoral systems under no‐till; and (c) the surface application of limestone does not increase soil compaction in agropastoral systems under no‐till. Core Ideas: The incorporation of limestone with plowing and harrowing does not decrease soil compaction.The subsurface application of hydrated lime with a shank subsoiler‐fertilizer does not decrease soil compaction.The surface application of limestone does not increase soil compaction. [ABSTRACT FROM AUTHOR]

Conservation management systems that have intended to prevent wear or soil degradation have been widespread in agriculture. The study was conducted in Site São Luiz at Simonsen district, Votuporanga, São Paulo State, in order to evaluate the chemical and physical changes in an area with agrosilvopastoral system and deployed with three soil management (treatments): Full (conventional tillage, liming and application of gypsum, phosphate and potassium); intermediate (no tillage, liming and application of gypsum at surface) and basic (no tillage and surface liming). The soil was managed in July 2009 and the planting of eucalyptus was realized in January 2010, on the terraces. Between the terraces it was cropped maize intercropped with Urochloa brizantha cv. Marandu. In April 2014 it was held the disturbed and undisturbed soil sampling soil at depths of 0-0.05 and 0.05-0.20 m, collecting three sub samples per plot. A randomized complete block experimental design was used with three replications, with plots of approximately 1.0 ha. It was concluded that in the layer of 0- 0.05m, the intermediate management provided increase in the levels of organic matter, Ca, P and K and the basic management provided lower levels of Ca and lower pH and basis saturation values and higher potential acidity; the complete and intermediate managements provided raising the pH in the two layers evaluated; the use of liming associated with gypsum application improves the chemical characteristics of Argisols under agrosilvopastoral systems; in the layer of 0.05-0.20 m the basic management provided lower bulk density and the complete management the largest; the different managements did not differ with respect to porosity and aggregate stability. [ABSTRACT FROM AUTHOR]

In the state of São Paulo, common bean is an important crop and the Agronomic Institute (Instituto Agronômico - IAC) registered the "carioca" (beige with brown stripes) bean cultivar IAC Imperador in the MAPA/RNC, exhibiting mean yield of 2,266 kg/ha in the 17 environments evaluated, a 75-day cycle, resistance to soil diseases and high quality seeds. [ABSTRACT FROM AUTHOR]