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

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.