Effect of liming on yields of five successive crops of maize followed by cotton and soybeans

Abstract

A liming experiment was conducted during seven years on a red-yellow podzolic soil of Mococa, state of São Paulo. Maize (Zea mays L.) was grown during the five first years and thereafter cotton and soybeans. The amounts of dolomitic limestone applied, with PRNT (relative power of total neutralization) of 59% were 0, 3, 6 and 9 t/ha. With 9 t/ha of applied limestone the pH reached 5,9. The effect of liming remained until the seventh year, although with losses of calcium and magnesium from the soil. The effect of liming on yield was highly significant for all crops. The increases in yield of maize of the first year would be sufficient to repay the investment with limestone. The aluminum criteria to determine the lime requirements of the soil of this experiment would indicate far too low amounts of limestone.