02335naa a2200397 a 450000100080000000500110000800800410001902400410006010000210010124500930012226000090021550001160022452011270034065000200146765000090148765000190149665000160151565000110153165000150154265000160155765000200157365000260159365000100161965000190162965000180164865000220166665000130168865300260170165300270172765300270175470000150178170000170179670000220181370000160183577300860185121047922019-01-25       2018    bl uuuu     u00u1 u    #d7 a10.1590/S0100-204X20180004000082DOI1 aMORAES, M. T. de  aCorn crop performance in an Ultisol compacted by tractor traffic.h[electronic resource]  c2018  aTítulo em português: Desempenho da cultura do milho em Argissolo Vermelho compactado pelo tráfego agrícola.  aThe objective of this work was to determine whether compaction by tractor traffic in areas managed under controlled traffic can be limiting to corn crop, under different tillage systems, in a Typic Paleudult of medium texture. Two experiments were carried out, one in the field over two crop seasons and another in a greenhouse. The treatments consisted of minimum tillage with chiselling; no-tillage subjected to one, three, or six passes of a tractor weighing 3.8 Mg; and an area without traffic. Evaluations were performed for soil physicohydraulic parameters (soil bulk density, penetration resistance, and water retention curve), root and shoot growth, and grain yield. The agricultural traffic increased bulk density, soil penetration resistance, and water content at field capacity. The highest values for soil penetration resistance (1,600 kPa) and bulk density (1.67 g cm-3) in the trafficked soil were not limiting to corn development and increased grain yield for both crop seasons. Tractor traffic of up to six passes is beneficial to corn cultivation, and it increases water availability and corn grain yield.  aCompacted soils  aCorn  aDirect seeding  aGrain yield  aGrains  aNo-tillage  aRoot growth  aSoil compaction  aCompactação do Solo  aMilho  aPlantio Direto  aProdutividade  aSistema Radicular  aZea Mays  aCrescimento radicular  aProdutividade de grão  aSistema plantio direto1 aLEVIEN, R.1 aTREIN, C. R.1 aBONETTI, J. de A.1 aDEBIASI, H.  tPesquisa agropecuária brasileira, Brasíliagv. 53, n. 4, p. 464-477, Apr. 2018.