Nitrogen Use Efficiency in Vegetable Crops

Laura L. Van Eerd, Ph.D., P.Ag.

Ridgetown College, University of Guelph

519-674-1644

Methodology

• Crops: – Cucumbers– Squash– Peppers– Carrots

• 3 sites for each crop• RCBD

– 4 reps– 6 to 8 treatments

Methodology

• N treatments – 0 N – Low (35 – 65 kg N ha-1) – OMAF recommendation – High (1.5x OMAF) – Very high (2x OMAF) – Split (Low + x = OMAF rec.) – UMAXX from Agrotain

Cucumbers0

65

110

165

220

65 + 45

110

Data Collection

• Soil sampling– Pre-site analysis (soil characteristics)– 2 week after treatment (mineral N)– At split application (mineral N)

• Plant sampling – At split application (nitrate)

• Harvest– Marketable yield– Soil (mineral N)– Shoot and fruit (% total N)

Results – Marketable Yield

Results – Crop N Uptake and Removal

N Applied (kg N/ha)

Crop Uptake

(kg N/ha)

Crop Removal

(kg N/ha)

0 34.2 (3.8) 27.5 (3.6)

110 44.9 (5.7) 30.8 (2.7)

220 48.7 (2.4) 31.9 (3.2)

NUE

-

12.8 (7.2)

8.6 (2.3)

NUE = Pnf – Pn0

fertilizer applied

Ammonia-N

Results – Soil Mineral N

Nitrate-N

Cover Crops