Response of potato (Solanum tuberosum L.) to nitrogen and phosphorus fertilizers at Sekota and Lasta districts of Eastern Amhara, Ethiopia

Abstract

Background Production and productivity of potato in Ethiopia is far below the world average because of soil fertility problem, pest, disease, and agronomic factors. Nutrient depletion because of soil erosion is a serious problem in Ethiopian highlands. Annually, 122 kg ha −1 nitrogen, 13 kg ha −1 phosphorous and 82 kg ha −1 potasium were estimated to deplete from Ethiopia (Haileslassie et al. 2005 ). From the essential nutrients especially, nitrogen and phosphorus are the most important influential elements for production of potato but they are deficient in most Ethiopian soils and thus an application of these nutrients could increase significantly the crop yields. Therefore, the experiment was conducted at Sekota and Lasta Lalibela districts (Woleh and Kechin Abeba irrigation command areas) of eastern Amhara, Ethiopia to investigate the effects of nitrogen and phosphorus fertilizers for yield and yield component of potato under irrigation condition. Methods Four rates of nitrogen (0, 46, 92, and 138 kg N kg ha −1 ) and phosphorus (0, 23, 46, and 69 Kg P 2 O 5 kg ha −1 ) were combined with factorial arrangement and laid out in randomized complete block design with three replications. Results The result of the study revealed that nitrogen and phosphorus had a significant effect on plant height, marketable, and total yield of potato at Kechin Abeba. But phosphorus did not show a significant effect on plant height and unmarketable yield at Sekota district of Woleh irrigation command area. The highest yield 45.55 t ha −1 was obtained from combined application of 138 N and 23 P 2 O 5 in Lalibela 17.12 and 16.99 t ha −1 were found from application of 138 N with 46 P 2 O 5 kg ha −1 and 138 N with 23 P 2 O 5 kg ha −1 from Sekota district of Woleh irrigation command area respectively. Conclusions The application of 138 kg ha −1 N with 23 kg ha −1 P 2 O 5 is the appropriate rates for optimum productivity of potato at Lalibela (Kechin Abeba) and Sekota (Woleh) irrigation command areas and the same agro-ecology.