Effect of Blended NPSB Fertilizer and Cattle Manure Rates on Growth, Yield and Quality of Potato (Solanum tuberosum L.) in Seka District, Jimma Zone, Southwestern Ethiopia

Abstract

Potato (Solanum tuberosum L.) is one of the most important tuber crops which is being produced in Ethiopia. However, the production and productivity of the crop is far below the world average due to poor crop variety, soil fertility and water management practices. Therefore, a field experiment was conducted in Southwestern Ethiopia ‘Seka district, under irrigation during the 2018/2019 off-season. Treatments consisted of four levels of NPSB (0, 61, 122 and 183 kg ha-1) and four levels of cattle manure (0, 10, 15 and 20kg ha-1) laid out in Randomized Complete Block Design (RCBD) in a 4x4 factorial with three replications. Data were collected on growth and yield parameters. The combined application of NPSB blended fertilizer and cattle manure significantly (P<0.005) influenced days to 50% flowering, days to 75% physiological maturity, plant height, total tuber yield (t ha-1), marketable tuber yield (t ha-1), total tuber number per hill, marketable tuber number per hill and specific gravity. However, main stem number and dry matter content were not affected by the combined application of NPSB blended fertilizer and cattle manure. Unmarketable tuber number and yield was also not affected by the main effects of NPSB blended fertilizer and cattle manure and as well as their interaction. The highest total tuber yield (40.08 t ha-1) was obtained by applying 183 kg ha-1 NPSB bended fertilizers+20 t ha-1 cattle manure. The combined application of 183 kg NPSB ha-1 bended fertilizers+20tha-1 cattle manure gave the maximum net return of Birr 193365.5ha-1 with an acceptable marginal rate of return (1726 %). The total nitrogen, available phosphorus and organic carbon content of the experimental soil were also increased due to the interaction of mineral NPSB blended fertilizers and cattle manure at their highest rates. The combined application of 122 kg ha-1NPSB blended fertilizers and 10 t ha-1 CM is found economically feasible for farmer which un able to buy much input. In conclusion, the results revealed that combined application of 183 kg ha-1NPSB fertilizers and cattle manure at 20 t ha-1 significantly increased total tuber yield (40.08tha-1) of potato and restore of N, P and organic carbon of soil. And can be recommended for potato growers around Seka district.