Productivity and economics of faba bean (vicia faba l.) in relation to integrated use of lime, blended fertilizer, biofertilizer and compost on acid soils of high lands in west showa zone of ethiopia

Faba bean (Vicia faba L.) is the most important legume crop being grown predominantly in the Ethiopian highlands of Oromia region where soil acidity and nutrient depletion pose serious limitation to land productivity. Field experiment was conducted during 2015 rainy season (July-Sept.) to investigate the effect of integrated nutrient and lime application on soil fertility and productivity of faba bean at Telecho, Wolmera district, in the highlands of Western Ethiopia. The investigation consisted of nine treatments namely- (t1):control, (t2): compost at 5t ha-1,(t3) :lime at 611kg ha-1, (t4): compost at 5t ha-1 + lime at 611kg ha-1,(t5): lime at 611kg ha-1 + DAP 150 kg ha-1 research recommendation (69 kg p2o5 ha-1) and biofertilizer (500 g ha-1), (t6):site specific recommendation (npsb at 150 kg ha-1, kcl at 100 kg ha-1)+ biofertilizer (500 g ha-1), (t7): lime at 611kg ha-1 + npsb at 150 kg ha-1, kcl at 100 kg ha-1 and biofertilizer (500 g ha-1, (t8): lime at 611kg ha-1 + compost at 5t ha-1 + npsb at 150 kg ha-1, kcl at 100 kg ha-1) and biofertilizer (500 g ha-1) (t9): lime at 611kg ha-1 + 2.5 t ha-1 compost and biofertilizer (500 g ha-1)with 50 % of soil test based fertilizer recommendation (npsb at 75 kg ha-1, kcl at 50 kg ha-1,). The experiment was laid out in a randomized complete block design (RCBD) with 3 replications. Soil samples were collected before and after lime application and analyzed for selected soil properties. Lime requirement was determined based on exchangeable acidity. Soil analysis result revealed that lime application raised soil pH from 3.80 to pH level ranging from 6.70 to 6.86.Yield and yield components of faba bean were significantly (p<0.05) affected by imposed treatments where in the highest and significant crop yield response was obtained with t8 (2882.9 kg ha-1). However, in most cases the difference in yield and yield attributes, and soil parameters due to t1, t2, t3,t4, t6, were not discernible suggesting that all elements of soil health and fertility issues need to be addressed together. The economic analysis indicated that the highest net return (38833.50 birr ha-1) and MRR (1333.94) was obtained with t9. Hence, it can be concluded that integrated use of lime at 611kg ha-1, bio fertilizer 500 g ha-1 + 2.5 t ha-1 compost along with 50 % of soil test based fertilizer recommendation (npsb at 75 kg ha-1, kcl at 50 kg ha-1, ) for faba bean is advisable for farmers in the study area and locations with similar agro-ecologies to maximize faba bean yield and economic return.