Abstract:
Potato (Solanum tuberosum L.) is one of the most important food security and cash crops in
Ethiopia due to its high production potential, nutritional quality, short growing period and
wider adaptability. However, Low soil fertility and crop nutrient imbalances management
practices are major constraints preventing Ethiopian farmers from realizing high agricultural
productivity. So far, the emphasis has not been given to assessing the influence of the
combined application of inorganic and organic fertilizer on the yield and quality of potato.
Thus, a field experiment was carried out during the main cropping season at Debre Berhan
University College of agriculture and natural resource science research site. The field
experiment was conducted with the objective of evaluating the effects of NPS fertilizer and
farmyard manure on the growth, yield and quality of potato. The treatments consisted of four
levels of NPS (0, 60, 120 and180 kg ha-1
) fertilizer and four levels of farmyard manure (0, 10,
20 and 30tha-1
) and an improved potato variety called ‘Gera’ (KP-90134.2) was used as a
test crop. The experiment was set out as a Randomized Complete Block Design (RCBD) in a
4x4 factorial arrangement and replicated three times. The results indicated that days to 50%
flowering, days to75% physiological maturity, total leaf area per plant (cm2
) and
unmarketable tuber yield (tha-1
) were significantly affected (P≤0.05) by application of the
main effect of 180kgha-1 NPS and 30tha-1 FYM fertilizer. The combined application of 180 kg
ha-1NPS fertilizer and30tha-1
farmyard manure resulted in the tallest plant
height(73.26cm),the highest main stem number(4.73),the highest number of branch(16.93),the
highest leaf number(378.86), the highest leaf area index (6.82), the highest marketable tuber
number per plant (25.53),the highest average tuber weight(88.26g tuber-1
), the highest total
tuber yield (32.68tha-1
) while the application of 30tha-1FYM and 180kgha-1
resulted in a non significant change in tuber quality of potato. The combined application of 180 kg ha-1 NPS
and 30tha-1 FYM fertilizer level gave the maximum economic benefit (Birr 119,758 ha-1
) with
an acceptable marginal rate of returns (1,636.1%). Hence, plots received 180 kg NPS ha-1
and
30t FYM ha-1
fertilizer level recommended for the production of potato in the study area and
similar agro- ecologies with acceptable economic benefit.
