Calcium, magnesium and potassium contents of soils influence growth and yield of crops, the relationships among those nutrients that result in the best plant development are, however, plant species dependent. The purpose of the present study was to analyse corn growth as a function of potassium fertilization and of the base saturation of the soil. An experiment was set up under greenhouse conditions with an early single corn hybrid "Zeneca 8392" grown in 30 L pots, filled with three types of soil (one Quartzpsamment and two alic- Haplorthox), with two levels of base saturation (40 and 70 %) and four rates of potassium (0, 60, 120 e 240 mg kg-1). A 3x2x4 completely randomized design was used, with four replications. Plant growth was analysed 29, 57 and 127 days after seedling emergence measuring internode length, leaf number, plant height and basal stem diameter. Plant development and grain yield increased up to a soil K application of 60 mg kg-1. Growth was rapid until flowering for the sandy soil. Average internode length increased for soils with the highest CEC. The average internode length was inversely related to internode number per plant, depending on soil texture.
liming; soil texture; length of internodes; plant height; number of leaves