02169naa a2200253 a 450000100080000000500110000800800410001910000190006024500960007926000090017550001290018452012880031365000200160165000190162165300160164065300300165665300260168670000210171270000200173370000300175370000180178370000210180177300930182211256792019-08-02       2008    bl uuuu     u00u1 u    #d1 aBEUTLER, A. N.  aSoil compaction by machine traffic and least limiting water range related to soybean yield.  c2008  aTítulo em português: Compactação do solo por tráfego de máquinas e intervalo hídrico ótimo na produtividade de soja.  aThe research aimed to evaluate machine traffic effect on soil compaction and the least limiting water range related to soybean cultivar yields, during two years, in a Haplustox soil. The six treatments were related to tractor (11 Mg weight) passes by the same place: T0, no compaction; and T1*, 1; T1, 1; T2, 2; T4, 4 and T6, 6. In the treatment T1*, the compaction occurred when soil was dried, in 2003/2004, and with a 4 Mg tractor in 2004/2005. Soybean yield was evaluated in relation to soil compaction during two agricultural years in completely randomized design (compaction levels); however, in the second year, there was a factorial scheme (compaction levels, with and without irrigation), with four replicates represented by 9 m2 plots. In the first year, soybean [Glycine max (L.) Merr.] cultivar IAC Foscarim 31 was cultivated without irrigation; and in the second year, IAC Foscarim 31 and MG/BR 46 (Conquista) cultivars were cultivated with and without irrigation. Machine traffic causes compaction and reduces soybean yield for soil penetration resistance between 1.64 to 2.35 MPa, and bulk density between 1.50 to 1.53 Mg m-3. Soil bulk density from which soybean cultivar yields decrease is lower than the critical one reached at least limiting water range (LLWR =0).  asoil management  aManejo do Solo  aGlicine max  aqualidade física do solo  asoil physical quality1 aCENTURION, J. F.1 aSILVA, A. P. da1 aCENTURION, M. A. P. da C.1 aLEONEL, C. L.1 aFREDDI, O. da S.  tPesquisa Agropecuária Brasileira, Brasília, DFgv. 43, n. 11, p. 1591-1600, nov. 2008.