Crop Response to Soil Acidity Factors in Ultisols and Oxisols in Puerto Rico. XII. Tomatoes

Abstract

The effect of acidity factors of two Ultisols and one Oxisol on yield and foliar composition of tomatoes was determined. Yields were not markedly reduced by acidity in the Ultisols until pH dropped to around 4.6 with 45% Al saturation of the cation exchange capacity (CEC), and no yield was produced at about pH 4.1 and 80% Al saturation. In the Oxisol, tomato yields dropped steadily from 39.7 t/ha, when there was no exchangeable AI, to 17.5 t/ha at the highest level of acidity, pH 4.4 and 43% AI saturation. In all soils, yields were closely correlated with soil pH, exchangeable Al and Ca and Al/Ca.