01778naa a2200169 a 450000100080000000500110000800800410001910000180006024500580007826000090013652013110014565000120145665000160146870000250148470000200150977300790152913355892019-09-17       1998    bl uuuu     u00u1 u    #d1 aERNANI, P. R.  aIncrease of grain and green matter of corn by liming.  c1998  aDespite the fact aluminium toxicity to crops is eliminated near soil water pH of 5.5, lime recommendation in many regions aims to increase soil pH up to 6.0 or even higher. For highly buffered soils, high rates of limestone are required to raise the pH from 5.5 to 6.0, resulting in additional, sometimes unnecessary, costs. The ojetive of this study was to evaluate the effect of soil pH on corn yiel in a very acid Hapludox. The experiment was carried out in Lages, Southern Brazil, from 1992 to 1996. The soil had water pH of 4.7 Al of 33 mmol kg, O.M. of 45 g kg and lime requirement to pH 6.0 of 9.0 t ha. Dolomitic limestoneat rates of0,4.5,9.0, 13.5 and 18.0 t ha (equivalent to pure CaCo) was incorpored into the soil down to 17 cm depth, in 1992. Liming increased linearly the values of soil pH (from 4.7 to 6.6) and Ca and Mg, eliminated Al with rates of 9.0 t ha or higher, decreased slightly Al-CuCl Fe and Cu, and did not affect Zn and Mn Maximum average corn yield for grain (7.9 t ha) and for green matter for silage (GM) 59 t ha) was obtained, respectively, at soil pH of 6.0 (12 t ha limestone) and of 6.1 (14 t ha of limestone); maximum economic efficiency for grain was obtained at pH 5.6 (7.5 t ha of limestone). Maximum vield increments due to liming were 17% for grain and 20% for GM.  aCalagem  aSolo Ácido1 aNASCIMENTO, J. A. L.1 aOLIVEIRA, L. C.  tRevista Brasileira de Ciencia do Solo, Campinasgv.22, n.2, 275-280, 1998.