Table 1.

Effect of nitrogen levels on the morphology structure of superior grains.

Year	Hybrid	N Treatment	Grain density	1000-grain weight	geometrical morphology of grain (cm)			Geometric volume of grain	Volume of grain
		kg ha−1	(g L−1)	(g)	Length	Width	Thickness	(cm3)	(cm3)
2010	Suyu20	0	1109 ± 35a	312.5 ± 13.2a	0.89 ± 0.04a	0.81 ± 0.02a	0.49 ± 0.02a	0.35 ± 0.01a	0.28 ± 0.01a
		360	1150 ± 27bc	416.3 ± 14.5d	1.03 ± 0.02c	0.94 ± 0.02b	0.52 ± 0.01a	0.5 ± 0.01c	0.36 ± 0.00c
		450	1198 ± 26c	439.5 ± 9.3e	1.24 ± 0.03e	1.06 ± 0.01c	0.53 ± 0.02a	0.7 ± 0.02f	0.37 ± 0.00c
		540	1124 ± 31ab	422.4 ± 8.8de	1.11 ± 0.01d	0.93 ± 0.02b	0.53 ± 0.01a	0.55 ± 0.01d	0.38 ± 0.00c
	Suyu29	0	1101 ± 36a	305.3 ± 10.8a	0.94 ± 0.03b	0.83 ± 0.01a	0.52 ± 0.02a	0.41 ± 0.01b	0.28 ± 0.01a
		360	1170 ± 27bc	368.1 ± 14.9b	1.03 ± 0.01c	0.92 ± 0.02b	0.51 ± 0.02a	0.48 ± 0.01c	0.31 ± 0.01b
		450	1196 ± 29c	426.9 ± 7.7de	1.21 ± 0.02e	1.09 ± 0.01c	0.52 ± 0.01a	0.69 ± 0.02e	0.36 ± 0.00c
		540	1131 ± 26ab	376.2 ± 9.2c	1.03 ± 0.03c	0.91 ± 0.02b	0.52 ± 0.02a	0.49 ± 0.01c	0.33 ± 0.01bc
2012	Suyu30	0	1123 ± 26a	234.7 ± 9.1a	0.96 ± 0.01b	0.69 ± 0.01a	0.51 ± 0.02b	0.34 ± 0.02a	0.21 ± 0.00a
		360	1198 ± 37bc	278.7 ± 14.6b	1.06 ± 0.03cd	0.81 ± 0.02b	0.47 ± 0.01ab	0.4 ± 0.02c	0.23 ± 0.00b
		450	1222 ± 38c	299.4 ± 7.9d	1.1 ± 0.03d	0.91 ± 0.02cd	0.48 ± 0.02ab	0.48 ± 0.01e	0.24 ± 0.01bc
		540	1195 ± 34bc	281.2 ± 11.8bc	1.09 ± 0.01cd	0.87 ± 0.01c	0.45 ± 0.02a	0.43 ± 0.02d	0.24 ± 0.01b
	Suyu20	0	1113 ± 37a	264.5 ± 12.1d	0.92 ± 0.02a	0.85 ± 0.02bc	0.47 ± 0.02ab	0.37 ± 0.01b	0.24 ± 0.01d
		360	1152 ± 34b	392.4 ± 12.3f	1.02 ± 0.04c	0.96 ± 0.02d	0.53 ± 0.01b	0.52 ± 0.01f	0.34 ± 0.00f
		450	1192 ± 34bc	418.8 ± 11.0g	1.23 ± 0.03e	1.08 ± 0.03e	0.52 ± 0.02b	0.7 ± 0.01h	0.35 ± 0.01g
		540	1131 ± 38ab	390 ± 10.1f	1.16 ± 0.03e	0.92 ± 0.03cd	0.53 ± 0.02b	0.56 ± 0.02g	0.34 ± 0.01g
	Suyu29	0	1106 ± 32a	264.3 ± 14.9c	0.98 ± 0.04b	0.82 ± 0.02b	0.53 ± 0.02b	0.42 ± 0.01cd	0.24 ± 0.00c
		360	1172 ± 36bc	348.2 ± 9.2e	1.05 ± 0.04c	0.9 ± 0.01cd	0.51 ± 0.01b	0.48 ± 0.02e	0.3 ± 0.00e
		450	1183 ± 32bc	405.9 ± 9.2f	1.19 ± 0.03e	1.08 ± 0.01e	0.52 ± 0.01b	0.67 ± 0.01h	0.34 ± 0.01f
		540	1143 ± 39ab	353.7 ± 11.0e	1.05 ± 0.03c	0.93 ± 0.02cd	0.52 ± 0.02b	0.51 ± 0.02f	0.31 ± 0.01e
F-value		Year	0.06 NS	245.81**	10.19*	0.51NS	0.05NS	2.3NS	369.21NS
		Hybrid	11.72**	758.82**	13.19**	101.73**	5.2*	169.73**	1539.3**
		N treatment	45.76**	858.57**	550.48**	240.31**	0.16NS	492.42**	913.87**
		Year × Hybrid	0.01NS	1.97NS	0.01NS	3.16NS	0.15NS	0.52NS	1.02NS
		Year × N treatment	0.48NS	8.94*	5.78**	0.26NS	0.07NS	2.3NS	21.93**
		Cultivar × N treatment	1.3*	48.39**	35.23**	5.73**	2.22NS	21.6**	107.99**
		Year × Hybrid×N treatment	0.04NS	0.35NS	1.87NS	1.4NS	0.25NS	0.18NS	1.63NS

Means in the same column followed by the same letter do not differ statistically at the 0.05 probability level by an ANOVA protected Duncan’s test; *^,**NS Significantly different at the 0.05 and 0. 01 probability levels and no significant difference, respectively.