Effect of type and rate of urea fertilizers on nitrogen use efficiencies and yield of wheat (Triticum aestivum) in Northern Ethiopia

Figures & data

Figure 1. Location of the experimental area within Ethiopia.

Table 1. Effect of N fertilization on wheat straw, grain and total yield

N application rate [kg N ha^−1]	Grain yield [kg ha^−1] n = 3	Straw yield [kg ha^−1] n = 3	Total yield [kg ha^−1] n = 3
0 (Control)	2383.67 d	4646.00 d	6963.00 e
23 (with SGU)	4065.67 c	6157.33 c	10,223.00 d
46 (with SGU)	4685.00 a	6861.33 b	11,581.33 b
69 (with SGU)	4720.00 a	7529.67 a	12,214.67 a
46 (with CU)	4187.33 b	6246.33 c	10,463.67 c
LSD (0.05)	107.24	127.76	197.88
SE (±)	38.47	49.9	70.39
CV (%)	1.42	1.08	1.02

“a–e indicate mean value; values within a column sharing a common letter are not significantly different (at P > 0.05)”, n = number of samples, SGU = super granular urea; CU = Conventional urea LSD = Least significant difference; SE = Standard error; CV = Coefficient of variation.

Table 2. Effect of N fertilization on wheat grain and straw N content and uptake for the five treatments (n = 5)

N application rate (kg N ha^−1)	N content in grain [%]	N content in straw [%]	N uptake into grain [kg N ha^−1]	N uptake into straw [kg N ha^−1]	Total plant N uptake [kg N ha^−1]
0 (Control)	1.95	0.46	46.48	21.37	67.85
23 (with SGU)	2.28	0.89	92.68	54.80	147.48
46 (with SGU)	2.48	1.12	116.19	76.85	193.04
69 (with SGU)	2.69	1.28	126.97	96.38	223.34
46 (with CU)	2.30	0.93	96.32	59.96	156.28

SGU = super granular urea; CU = Conventional urea.

Table 3. Effects of N fertilizer application on apparent fertilizer N recovery (AR), agronomic use efficiency (AE) and physiological use efficiency (PE) of wheat

N application rate [kg N ha^−1]	Apparent fertilizer recovery [%]	Agronomic use efficiency [kg grain kg^−1 plant N]	Physiological use efficiency [kg grain kg^−1 plant N]
0 (Control)	-	-	-
23 (with SGU)	346	73.13	21.12
46 (with SGU)	272	50.05	18.38
69 (with SGU)	225	33.86	15.03
46 (with CU)	192	39.21	20.40

SGU = super granular urea; CU = Conventional urea.