Table 1.

Grain yield and nitrogen use efficiency parameters in mature plants of five barley genotypes

Nutrient supply	Genotype	Grain dry mass (g)a	Grain N concentration (%)b	N uptake efficiency (g plant N/g N supplied)b	N utilization efficiency (g grain/g plant N)	N use efficiency (g grain/g N supplied)
Standard nutrient	Kenia	3.86±0.81	2.77±0.23	0.257±0.048	24.60±2.62	6.60±1.34
	Golden Promise	3.50±0.77	2.57±0.17	0.196±0.046c	28.86±2.02	5.94±1.58c
	B83	4.10±0.93	2.74±0.44	0.244±0.034	28.04±5.44	6.96±1.62
	Westminster	4.28±0.70	2.04±0.15	0.207±0.025	34.35±2.35	7.20±1.09
	Derkado	3.53±0.95	2.51±0.42	0.223±0.031	27.04±5.26	5.96±1.49
Reduced nutrientd	Kenia	0.90±0.28	2.41±0.14	0.120±0.024	25.70±3.48	3.08±0.89
	Golden Promise	1.51±0.38	2.42±0.22	0.164±0.014c	36.73±4.22c	5.01±1.20
	B83	1.13±0.30	2.29±0.24	0.116±0.027	32.81±2.48	3.77±0.92
	Westminster	1.04±0.34	2.16±0.25	0.094±0.022	34.84±5.73	3.54±1.02
	Derkado	0.81±0.37	2.28±0.31	0.107±0.030	26.98±6.17	2.81±1.17
GLM ANOVA	Nutrient	F1,36=44.66, P <0.001	F1,36=1.72, P >0.1	F1,34=28.12, P <0.001	F1,35=1.30, P >0.1	F1,35=16.72, P <0.001
	Genotype	F4,36=0.47, P >0.1	F4,36=1.26, P >0.1	F4,34=0.50, P >0.1	F4,35=2.21, P <0.1	F4,35=0.34, P >0.1
	Interaction	F4,36=0.36, P >0.1	F4,36=0.32, P >0.1	F4,34=1.52, P >0.1	F4,35 =0.34, P >0.1	F4,35=0.53, P >0.1

Values are mean ±SE of n=5 plants.

^aAnalysis performed on ln-transformed data.

^bAnalysis performed on arcsin-square root-transformed percentage data.

^cFor these values, n=4 plants.

^dReduced nutrient supply was 50% of the standard nutrient supply.