The Effects of Combined Application of Cattle Manure and NP Fertilizers on Yield and Nutrient Uptake of Potato in North-Eastern Ethiopia

Abstract

Potato (Solanum tuberosum L.) is a short season crop that thrives best under sufficient nutrient supply. However, in Ethiopia the yield of potato is quite low as it is produced with little or inappropriate rates of fertilizer application. Therefore, a field experiment was conducted for two seasons (2012 and 2013) at Kobo substation of Sirinka Agricultural Research Centre to elucidate the combined effects of cattle manure (CM) and NP fertilizers on growth, yield components, yield and nutrient uptake of the crop. The treatments consisted of three rates each of CM (0, 15 and 30 t ha-1), nitrogen (0, 60 and 120 kg N ha-1) and phosphorus (0, 46 and 92 kg P2O5 ha-1), combined factorially and laid out in randomized complete block design with three replications. Growth parameters (growth rate, and leaf area), average tuber weight and marketable and total tuber yield of potato were significantly (P ≤ 0.05) influenced by the interaction effects of chemical and organic fertilizers. Uptake of N and P were higher with treatments in which 30 t ha-1 CM was applied combined with 120 kg N and 92 kg P2O5 ha-1 as compared to the control treatment. Harvest index, total tuber yield, N uptake and P uptake were significantly increased by 134%, 257%, 2446% and 1186%, respectively, over the control treatment in response to the combined application of 120 kg N, 92 kg P2O5 ha-1 and 30 t ha-1 CM. In conclusion, the results revealed that integrated application of chemical and organic fertilizers could be the best strategy to restore highly depleted soils and to enhance economical production of potato in Kobo district and similar agroecologies.