International Scholarly Research Notices

Research Article

Nitrogen Fertilizer Rate and Cultivar Interaction Effects on Nitrogen Recovery, Utilization Efficiency, and Agronomic Performance of Spring Barley

Table 4

Nitrogen use efficiency traits of three spring barley cultivars grown under three rates of N fertilizer (0, 50, and 100 kg ha⁻¹) at Lacombe, Alberta, Canada, during 1994 to 1996.


Variable Cultivar	N rate	NUE(kg kg⁻¹ N)	ANUE (kg kg⁻¹N)	UtE (kg kg⁻¹N)	BPE (kg kg⁻¹N)	HI (%)	Grain N content (%)

Manley	0	46.7a	—	45.1a	85.2a	54.3a	1.69c
	50	32.5b	22.8	38.7a	75.9ab	53.2ab	1.95b
	100	21.8c	6.6	30.1b	60.7b	50.8b	2.31a

Noble	0	46.9a	—	46.9a	81.5a	58.6	1.71c
	50	32.6 b	23.0	39.0a	68.6a	58.1	1.99b
	100	25.5c	17.2	34.9b	61.5b	58.5	2.15a

Tukwa	0	45.8a	—	47.9a	85.5a	56.8b	1.67c
	50	33.2 b	29.7	41.1ab	71.1ab	59.3ab	1.86b
	100	25.5 c	21.2	38.0b	64.1b	60.9a	2.03a

Mean	0	46.5a	—	46.6a	84.1a	56.6	1.69c
	50	32.8b	25.2	39.6b	71.9b	56.7	1.93b
	100	24.1c	15.0	34.3c	62.1c	56.9	2.16a

NUE, nitrogen use efficiency, grain yield per unit of available N (soil N + applied); ANUE, applied nitrogen use efficiency, increase in grain yield over unfertilized control per unit of applied N; UTE, nitrogen utilization efficiency, final grain yield per unit of N uptake; BPE, biomass production efficiency, biomass yield per unit of N taken up; and HI, harvest index, the ratio of grain yield to biomass at harvest maturity.
Means of different N rates within cultivar or overall mean followed by different letters are significantly different at .