Abstract

Low soil fertility and inadequate improved high yielding varieties are the major constraints for bean production in Ethiopia. In order to improve productivity, common bean varieties response to rate of NPKSB fertilizer was studied at Arba Minch during 2017 cropping season with three common bean varieties (Hawassa-Dume, Nasir, and Red Wolaita) and eleven fertilizer level (control, 41:46 kg NP ha^-1, 20.5:23:3.5:0.05 kg NPSB ha^-1, 41:46:7:0.1 kg NPSB ha^-1, 61.5:69:10.5:0.15 kg NPSB ha^-1, 20.5:23:30:3.5:0.05 kg NPKSB ha^-1, 41:46:30:7:0.1 kg NPKSB ha^-1, 61.5:69:30:10.5:0.15 kg NPKSB ha^-1, 20.5:23:60:3.5:0.05 kg NPKSB ha^-1, 41:46:60:7:0.1 kg NPKSB ha^-1, 61.5:69:60:10.5:0.15 kg NPKSB ha^-1). The treatments were combined in factorial experiments with split plot design and replicated three times. Analysis of the data indicated that nodulation, plan height, number of pods per plant, hundred seed weight and grain yield were significantly (p<0.05) affected due to blended NPKSB fertilizer application rate and common bean varieties. The highest number of total nodules (129.8 cm), effective nodules (122.3 cm) and plant height (124.6 cm) were recorded from variety Nasir, whereas the highest number pods per plant (28.9), seeds per pod (5.35), grain yield (2693.6 kg ha^-1), hundred seed weight (26.6 g) and harvest index (0.20) were recorded from variety Hawassa-Dume. Highest number of total nodules (137.7), number of effective nodules (130.7), plant height (129.4 cm), above ground dry biomass (17195 kg ha^-1), number of pods per plant (31.3) and grain yield (2923.8 kg ha^-1) were recorded from the maximum rate of blended NPKSB rate (61.5:69:60:10.5:0.15 kg NPKSB ha^-1) applied, however, it was statistically at par with rate 61.5:69:30:10.5:0.15 kg NPKSB ha^-1, 41:46:60:7:0.1 kg NPKSB ha^-1 and 41:46:30:7:0.1 kg NPKSB ha^-1,while maximum hundred seed weight (27.4 g) was recorded from 61.5:69:30:10.5:0.15 kg NPKSB ha^-1 however, it was statistically at par with treatment 61.5:69:60:10.5:0.15 kg NPKSB ha^-1, 41:46:60:7:0.1 kg NPKSBha^-1 and 41:46:30:7:0.1 kg NPKSB ha^-1. Economics of bean cultivation analysis showed that variety Hawassa-Dume and application of blended fertilizer rates of 41:46:30:7:0.1 kg NPKSB ha^-1 resulted maximum net benefit of 27435.1 birr ha^-1 and 27251.8 birr ha^-1, respectively. Thus, blended fertilizer at rate of 41:46:30:7:0.1 kg NPKSB ha^-1 and variety Hawassa-Dume is tentatively suggested to study area.

Keywords: Blended fertilizer; Economics; Fertility; Productivity