Participatory Research for Integrated Nutrient Management (INM): The Case of Potato Production in Central Highlands of Ethiopia

Background and Objective: Integrated use of organic and inorganic fertilizers can improve soil fertility and potato productivity. The study was initiated in the central highlands of Ethiopia to determine the influence of INM on potato tuber yield through FRG and FFS extension approach. Materials and Methods: Integrated Nutrient Management of potato was evaluated through both Farmers Field School and Farmers Research Group participatory research methods in Jeldu, Dendi, Welmera, and Alemaya districts during 2004-2006 to investigate the influence of inorganic fertilizer, compost and their mixture application on yield, yield components of potato. The treatments included three improved potato varieties, nationally recommended fertilizer rate of (165 kg/ha Urea and 195 kg/ha DAP) and recommended compost at a rate of 10 t/ha. The experiment was laid out as a randomized complete block design with three replications. Results: At all locations, regardless of potato varieties, application of inorganic fertilizer gave significantly highest yield followed by the mixture of organic and inorganic fertilizers. Application of inorganic fertilizer gave 6% over the control while inorganic fertilizer application gave 45% yield advantage over the control. The mixture of organic and inorganic fertilizer gave 20% less tuber yield as compared to inorganic applied treatment but gave 19% and 25.3% more yields over the organic and the control, respectively. Inorganic fertilizer gave 37% more tuber yields over the organic treatment and 16% more yield over the mixed fertilizer treatment. However, the mixture of organic and inorganic fertilizers gave 18.1% over the organic fertilizer applied treatment. Potato variety Degemegn gave the highest tuber yields in both seasons 2005 and 2006 as compared to variety Jalenie and Menagesha. In general, application of inorganic fertilizers leads to higher tuber yields in all locations and in all varieties except the yield obtained at Jeldu site on 2005. Conclusions: Regarding the treatments, inorganic fertilizer was the top yielder in most of the locations and varieties and mixed fertilization was the second followed by organic composting. Hence resource poor farmers could adopt the mixed approach which is less expensive. Therefore, use of compost as fertilizers will have positive effects beyond the potato season due to its slow releasing of nutrients and will reduce the cost of production giving comparable yields with the one acquired using inorganic fertilizers. Keywords: Integrated Nutrient Management, Farmer Research Group, Farmer Field School, Soil fertility, Potat