. 2017 Jun 8;12(6):e0178494. doi: 10.1371/journal.pone.0178494

Table 3. Effects of irrigation and nitrogen application on TAA, EAA and NAA content in wheat grain in 2012/2013, 2013/2014 and 2014/2015, and interactions between irrigation and nitrogen application; summary of F significance from analysis of variance of the effects of main factors and interaction.

Treatment	TAA (mg·g^-1)			EAA (mg·g^-1)			NAA (mg·g^-1)			EAA/TAA (%)
Treatment	2012/2013	2013/2014	2014/2015	2012/2013	2013/2014	2014/2015	2012/2013	2013/2014	2014/2015	2012/2013	2013/2014	2014/2015
I0	127.29	128.98a	125.30	38.93	40.33a	38.46	88.36	88.65a	86.84	30.61	31.32b	30.75
I1	119.40	125.25b	126.18	38.08	39.73ab	38.55	81.40	85.53b	87.63	30.90	31.79a	30.66
I2	125.92	124.14b	131.30	38.85	39.36b	40.28	87.07	84.78b	91.02	31.02	31.74a	30.83
F-test	ns	^**	ns	ns	^*	ns	ns	^**	ns	ns	^**	ns
N0	114.38b	115.72c	96.69c	35.56c	37.08c	30.91c	78.82b	59.64c	65.78c	31.28a	32.04a	31.98a
N180	122.84b	121.34b	134.62b	38.06bc	38.44b	40.82b	84.79b	82.90b	93.80b	31.03ab	31.71a	30.33b
N240	136.02a	133.37a	138.33a	41.41ab	41.62a	42.03a	94.72a	91.74a	96.30a	30.54b	31.21b	30.39b
N300	140.23a	134.06a	140.73a	42.80a	42.07a	42.62a	97.43a	91.99a	98.11a	30.52b	31.39b	30.29b
F-test	^**	^**	^**	^**	^**	^**	^**	^**	^**	^*	^*	^**
I0×N0	107.63b	136.60a	99.43b	33.46b	42.47a	31.33b	74.17b	94.13a	68.10b	31.09a	31.09b	31.52a
I0×N180	131.43a	104.27b	131.57a	40.10a	33.43b	40.13a	91.33a	70.83b	91.43a	30.51b	32.07a	30.51b
I0×N240	134.83a	137.20a	132.83a	40.90a	42.40a	40.57a	93.93a	94.80a	92.27a	30.33b	30.91b	30.54b
I0×N300	135.27a	137.87a	137.37a	41.27a	43.03a	41.80a	94.00a	94.83a	95.57a	30.51b	31.21b	30.43b
F-test	^**	^**	^**	^**	^**	^**	^**	^**	^**	^**	^**	^**
I1×N0	144.10	103.40b	94.20c	43.43	33.90b	30.07c	100.67	69.50b	64.13c	30.15	32.78a	31.92a
I1×N180	106.43	130.50a	132.43b	33.77	41.27a	40.20b	72.67	89.23a	92.23b	31.74	31.63b	30.35b
I1×N240	131.00	133.27a	138.07a	40.53	41.63a	41.77a	90.80	91.63a	96.30a	31.15	31.24b	30.25b
I1×N300	146.07	133.83a	140.03a	44.60	42.10a	42.17a	101.47	91.73a	97.87a	30.55	31.46b	30.11b
F-test	ns	^**	^**	ns	^**	^**	ns	^**	^**	ns	^**	^**
I2×N0	91.40b	107.17b	96.43b	29.77b	34.87b	31.33c	61.63b	72.30b	65.10b	32.58a	32.54a	32.49a
I2×N180	130.67a	129.27a	139.87a	40.30a	40.63a	42.13b	90.37a	88.63a	97.73a	30.85b	31.43b	30.12b
I2×N240	142.23a	129.63a	144.10a	42.80a	40.83a	43.77a	99.43a	88.80a	100.33a	30.12b	31.50b	30.37b
I2×N300	139.37a	130.50a	144.80a	42.53a	41.10a	43.90a	96.83a	89.40a	100.90a	30.52b	31.49b	30.32b
F-test	^**	^**	^**	^**	^**	^**	^**	^**	^**	^**	^**	^**
Grand mean	124.23	126.13	127.60	38.62	39.81	39.10	85.61	86.32	88.50	30.84	31.62	30.75
I×N (F-test)	^**	^**	^*	^**	^**	^**	^**	^**	^*	^**	^**	^**
CV (%)	13.15	0.84	0.87	3.37	0.19	0.22	9.71	0.68	0.68	1.10	0.20	0.14

Note: TAA: total amino acid; EAA: essential amino acid; NAA: non-essential amino acid. ns, not significant at P < 0.05;

* Significant at P < 0.05;

** Significant at P < 0.01; Data in the same column with different letters indicate a significant difference at P < 0.05.