Response of Haricot Bean Varieties to Different Levels of Iron Application in Selected Areas of Ethiopia

Abstract

Haricot bean (Phaseolus vulgaris L.) can be an important source of Fe for human nutrition, particularly in regions in which human Fe deficiencies are known to occur. A study using replicated field and greenhouse experiments was conducted in Ethiopia to evaluate the yield and Fe uptake response of different haricot bean varieties (Nasir, Ibado, Hawassa Dume, and Sari-1) to different levels of foliar-applied iron (Fe) fertilizer (0, 1, 2, and 3% solution). Pot experiment results indicated yield, yield components, and tissue Fe concentrations varied among varieties and across soils. The variety Ibado yielded the highest leaf Fe concentration (290.19 mg kg^-1) whereas Hawassa Dume had the highest number of pods per plant (7.28) and grain yield (15.85 g per pot). Varieties Sari-1 and Nasir produced the highest number of seeds per pod (4.94) and seed Fe concentration (59.02 mg kg^-1), respectively. Levels of Fe fertilization did not significantly influence yield and yield components, but significantly increased both leaf and seed Fe concentrations. Application of 3% FeSO₄.7H₂O produced the highest concentration of both leaf (339.50 mg kg^-1) and seed Fe (53.46 mg kg^-1). Field experiments revealed that haricot bean varieties significantly varied in yield, yield components, and leaf and seed Fe concentration. Highest grain yield (3099.55 kg ha^-1) was observed with variety Hawassa Dume. Production was significantly influenced by planting season and location. Overall, 3% FeSO₄.7H₂O fertilizer application best improved the quality of haricot bean produced.

Keywords: Haricot bean, Iron, Concentration, Varieties, Seed Fe, Leaf Fe