Search and Access Archived Conference Presentations

The 2011 ASHS Annual Conference

Nitrogen Application, Uptake and Loss In California Strawberry Production

Tuesday, September 27, 2011: 8:15 AM
Queens 6
Tom Bottoms, UC Davis, Davis, CA
Mark Bolda, University of California Cooperative Extension, Watsonville, CA
Michael Cahn, UC Cooperative Extension, Salinas, CA
Timothy K. Hartz, University of California, Davis, CA
Strawberry (Fragaria x ananassa Duch.) is a major crop in coastal California, an area with widespread NO3-N impairment of both surface water and groundwater.  A commercial field survey was begun in 2010 with the objectives of 1) determining the N uptake of day-neutral strawberry grown in an annual production system, and 2) evaluating current N fertilizer practices and the potential for N loss to the environment.  Thirteen fields of ‘Albion’ strawberry and 14 fields of a proprietary cultivar grown in the Watsonville-Salinas area were sampled at monthly intervals from March through August.  Root zone soil NO3-N and total leaf N were determined at each sampling date.  At two sites for each cultivar whole plant sampling for biomass and biomass N was also conducted.  Leachate NO3-N was monitored by automated suction lysimetry in 3 fields.  Cooperating growers provided data on seasonal N fertilization and fruit yield.  Crop N uptake was linear through the sampling period, averaging approximately 1.2 kg ha-1 day-1.  By the end of August total N uptake averaged 190 kg ha-1 across the 4 biomass monitoring sites, with N content nearly evenly split between vegetative tissue and fruit.  Seasonal N application varied from 138 to 337 kg ha-1, averaging 213 kg ha-1; approximately half was applied as controlled release fertilizer at crown planting the previous fall, and the remainder was fertigated through drip irrigation during the production season.  Soil NO3-N concentration below 10 mg kg-1 was maintained in most fields from April through August, the period of intensive irrigation.  Leachate NO3-N was correlated with root zone soil NO3-N, and in-season N loss was modest.  Mean leaf N declined from and average of 32 g kg-1 in March (before harvest initiation) to 27 g kg-1 at the fruiting peak.  Seasonal fruit yield averaged 74 Mg ha-1, compared to the state average of 68 Mg ha-1.  Neither fruit yield nor leaf N was correlated with N fertilization rate.
See more of: Plant Nutrient Management 1
See more of: Oral Abstracts