Soil pH is an important soil chemical property of acid soils that profoundly affects the growth and nutrient uptake by crops. Five greenhouse experiments were conducted to evaluate responses of common bean (Phaseolus vulgaris L.), lowland rice (Oryza sativa L.), corn (Zea mays L.), soybean (Glycine max L. Merr.), and wheat (Triticum aestivum L.) to mean soil pH values of 4.9, 5.9, 6.4, 6.7, and 7 on an Inceptisol. Relative dry matter yield (DMY) of shoots of all the crops tested was significantly affected by soil pH. Based on the quadratic response optimum pH for maximum relative Dry matter yield of wheat was 6.3, for soybean 5.6, for corn 5.4, for common bean 6 and for rice 4.9. This shows that crops responded differently to soil acidity. Among the crops tested, rice was the most tolerant and wheat was the most intolerant to soil acidity. On an average concentration of calcium (Ca) and potassium (K) in the plant shoots increased quadratically with increased soil pH except K concentration in the shoots of corn and soybean decreased. Magnesium (Mg) concentrations in the shoots of common bean and wheat decreased with increasing soil pH but in lowland rice, corn, and soybean increased quadratically with increasing soil pH. Phosphorus (P) concentrations in the shoots of common bean, wheat, and corn was increased but in lowland rice and soybean decreased with increasing soil pH. With few exceptions, most of the micronutrients concentrations decreased with increasing soil pH.
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