. 2018 Mar 22;9:385. doi: 10.3389/fpls.2018.00385

Table 4.

Nitrogen use efficiency from different treatments.

Treatments	2013			2014
	NRE (%)	NAE (kgkg^-1)	NFP (kgkg^-1)	NRE (%)	NAE (kgkg^-1)	NFP (kgkg^-1)
N0	–	–	–	–	–	–
IF	26.63 ± 2.84	8.24 ± 1.61	44.21 ± 1.53	37.45 ± 4.34	7.26 ± 1.29	48.88 ± 0.99
OF	22.81 ± 2.80	5.37 ± 0.88	41.34 ± 1.42	23.51 ± 2.57	4.28 ± 1.15	45.89 ± 0.69
OFIF	37.76 ± 3.48	10.79 ± 0.65	46.76 ± 0.96	41.57 ± 4.17	12.64 ± 3.95	54.26 ± 3.50
SRIF	47.10 ± 2.43	15.19 ± 2.83	51.76 ± 2.63	59.24 ± 3.93	11.54 ± 1.19	53.16 ± 1.35
NT	32.80 ± 10.19	10.03 ± 3.88	46.22 ± 3.95	39.19 ± 12.84	9.31 ± 4.30	50.62 ± 4.21
CT	34.35 ± 10.44	9.77 ± 4.32	45.51 ± 4.25	41.69 ± 14.60	8.55 ± 3.85	50.48 ± 3.73
F-value
N source	83.44^∗∗	29.76^∗∗	30.14^∗∗	100.39^∗∗	15.57^∗∗	19.59^∗∗
Tillage practice	1.64^ns	0.110^ns	0.88^ns	2.90^ns	0.60^ns	0.03^ns
N source × Tillage practice	0.60^ns	0.25^ns	0.25^ns	1.20^ns	0.24^ns	0.30^ns

Different letters between N fertilizer treatments under the same tillage practice indicate significant differences at the 5% level. N0, no N fertilizer; IF, inorganic N fertilizer; OF, organic N fertilizer; SRIF, slow-release N fertilizer combined with inorganic N fertilizer; OFIF, organic N fertilizer combined with inorganic N fertilizer; CT, conventional intensive tillage; NRE, N recovery efficiency; NAE, N agronomic efficiency; NFP, N partial factor productivity; NT, no-tillage; CT, conventional intensive tillage. “^∗∗” means P < 0.01; ns, not significant.