Abstract

Plants grown in acid soils experience a variety of stresses which include aluminium, hydrogen and/or manganese toxicity, as well as nutrient deficiencies of calcium and magnesium. A study was carried out to determine the influence of soil pH levels on iron and zinc concentrations in leaves and seeds of twenty-five common bean genotypes. Plastic cups trial was carried out in the screen house to determine the actual amount of quick lime Ca(OH)2  required to reach a targeted soil pH level. In each pot, 4 kg soil was amended with Ca(OH)2 to obtain the target soil pH levels of 5.3, 5.5, 6.5 and 7.5. The experimental design followed a randomized complete block design in a split plot arrangement with three replications per treatment. The pH levels were treated as main factor and genotypes as sub plot. Data collected include leaf iron concentration, seed iron concentration, leaf zinc concentration, and seed zinc concentration and analysis of variance was performed for all data using GenStat statistical package 15th edition. The result demonstrated that soil pH affects absorption of micronutrients directly or indirectly by affecting the nutrients availability to common bean plants.

Key words: Soil pH, micronutrients, zinc, iron, genotype, lime, common bean.