Table 4.

Nitrogen utilization efficiency in the various treatments.

Year	Treatments	NHI	PFP	NGPE (kg kg-1)	AE∗ (kg kg-1)	PE ∗ (kg kg-1)	SNDR (%)	RE ∗ (%)
2014	TFA180	0.76	61.69	56.32	12.14	44.06	74.88a	27.57b
	OFA180	0.77	67.63	52.51	18.08	38.04	63.65b	47.34a
	F value	1.54ns	2.30ns	1.31ns	2.32ns	0.40ns	15.28**	33.83**
2015	TFA90	0.72a	107.75a	64.41a	12.85	42.95	81.79a	30.98b
	OFA90	0.73a	114.52a	54.60ab	19.62	28.99	65.67b	72.86a
	TFA180	0.67b	59.76b	58.77ab	12.31	38.07	67.29b	33.52b
	OFA180	0.68b	65.41b	49.84b	17.96	28.26	52.38c	62.69a
	TFA	0.70	83.76	61.59a	12.58	40.51	74.54a	32.25b
	OFA	0.71	89.97	52.22b	18.79	28.62	59.03b	67.78a
	F value	1.73ns	5.87ns	6.54*	4.39ns	1.41ns	29.60**	20.25**
	N90	0.73a	111.14a	59.51	16.23	35.97	73.73a	51.92
	N180	0.67b	62.58b	54.31	15.13	33.16	59.83b	48.11
	F value	24.81**	358.73**	1.96ns	0.14ns	0.09ns	24.13**	0.36ns
2016	TFA180	0.70	59.12b	55.53	17.76b	38.13	55.85	47.04
	OFA180	0.70	66.46a	51.18	25.10a	36.22	45.93	71.21
	F value	0.52ns	44.57*	1.44ns	44.57*	0.23ns	6.91ns	5.19ns

^∗These parameters were standardized for the control (CK) values. TFA: traditional nitrogen fertilizer application; OFA: optimized nitrogen fertilizer application; 90: total nitrogen application rate was 90 kg ha^-1; 180: total nitrogen application rate was 180 kg ha^-1.; RE: recovery efficiency; AE: agronomic efficiency; PE: physiological efficiency; NHI: nitrogen harvest index; PFP: partial factor production for applied nitrogen; NGPE: nitrogen grain production efficiency; SNDR: soil nitrogen dependent rate. Data represent mean values of three biological replicates, different lowercase letters beside numbers within the same column indicate significant differences at the 0.05 probability level according to the least significant difference (LSD) multiple-range test. “^∗”, and “^∗∗” indicate significant differences between treatments at the 0.05 and 0.01 probability levels, respectively; “ns”: not significant at the 0.05 probability level.