Responses of common bean (Phaseolus Vulgaris L.) to applications of NPSZnB in different combinations in Debub Ari District, Southwestern Ethiopia

Abstract

Production and productivity of common bean in Debub Ari District declines mainly due to soil fertility depletion coupled with the use of inappropriate rates of fertilizers.A field experiment was conducted during 2019 to find out the effects of different combinations of NPSZnB fertilizers on yield and yield components of common bean The experiment consisted of 11 treatments viz. control, NPK (64:46:30 kg ha^-1), NPKS (42:38:30:7 kg ha^-1), NPKS (51.5:57:30:10.5 kg ha^-1), NPKS (61:76:30:14 kg ha^-1), NPKSB (41.1:36.1:30:6.7:0.71 kg ha^-1), NPKSB (50.15:54.15:30:10.05:1.07 kg ha^-1), NPKSB (59.2:72.2:30:13.4:1.42 kg ha^-1), NPKSBZn (39.9:33.8:30:7.3:0.67:2.23 kg ha^-1), NPKSBZn (48.35:50.7:30:10.95:1:3.35 kg ha^-1), and NPKSBZn (56.8:67.6:30:14.6:1.34:4.46 kg ha^-1) (i.e. in all treatments P is in the form of P₂O₅ and K is K₂O). Fifty kg ha^-1 of Muriate of Potash with grade of 0-0-30 was used in the form of band application in all treatments except the for control plot. The experiment was laid out in Randomized Complete Block Design with three replications. Soil samples collected from the experimental field before planting showed sandy loam in texture, slightly acidic in reaction, very low in organic carbon, low in total nitrogen, available P, K and Zn, medium available B, extractable S, and moderate cation exchange capacity. Application of different nutrients significantly (p < 0.05) increased most yield and yield parameters of common bean compared to the control plots. The maximum grain yield of 3477.0 kg ha^-1 and 3397.6 kg ha^-1 were obtained with rates of 59.2:72.2:30:13.4:1.42 and 50.15:54.15:30:10.05:1.07 kg ha^-1 of NPKSB applications, respectively while the minimum grain yield (1857.9 kg ha^-1) was recorded for the control. The application of NPKSB with rates of 50.15:54.15:30:10.05:1.07 kg ha^-1 had maximum and acceptable Marginal rate of return (MRR %) and net benefit. Therefore, NPKSB with rates of 50.15:54.15:30:10.05:1.07 kg ha^-1) is recommended for common bean production in the study area.