California produces more than 80% of the U.S. strawberry crop (USDA, Economic Research Service, 2012) with production centered in the coastal valleys of central California. In this region an annual cropping system is used in which transplants are planted into fumigated, plastic mulched beds in the fall and usually grown for 9 to 12 months. Sprinkler irrigation is generally used to establish the transplants with drip irrigation used exclusively thereafter. N fertility is typically managed by a combination of preplant CRF application and in-season N fertigation. There has been a significant evolution over recent decades in cultural practices used and in cultivars grown; yields have increased 140% over the past 50 years (Shaw and Larson, 2008) and now commonly exceed 70 Mg·ha−1.
Water quality monitoring in these coastal valleys has shown that groundwater often exceeds the Federal drinking water standard of 10 mg·L−1 NO3-N. Consequently, strawberry growers are under increasing regulatory pressure to improve their management practices to protect groundwater. Recently proposed regulations would require growers to report N fertilization rates and to bring N application into approximate balance with crop N uptake. Annual N uptake by strawberry crops has been reported to range from 59 kg·ha−1 to 200 kg·ha−1 (Albregts and Howard, 1980; Latet et al., 2002; Strik et al., 2004; Tagliavini et al., 2004, 2005). There is no reliable information on strawberry crop N uptake or grower N fertilization practices in California strawberry production, so it is unclear whether significant modification of current practices would be required to meet regulatory goals.
Studies in other strawberry production regions have indicated that no more than a seasonal total of 155 kg·ha−1 N was necessary to maximize fruit yield in annual production systems (Albregts et al., 1991a; Hochmuth et al., 1996; Kirschbaum et al., 2006; Locascio and Martin, 1985; Miner et al., 1997; Santos and Chandler, 2009). Splitting N application between preplant fertilization and in-season fertigation has been shown to be beneficial. Preplant application of no more than 67 kg N/ha (Albregts and Chandler, 1993; Miner et al., 1997) and in-season fertigation averaging between 0.5 and 0.9 kg·ha−1·d−1 (Hochmuth et al., 1996; Miner et al., 1997; Santos and Chandler, 2009) were adequate to achieve peak fruit production. However, these studies reported on production systems with different environmental conditions, shorter production seasons, and lower yield and therefore may not be directly applicable to California conditions.
Irrigation is intrinsically linked to N management both as an N application method and as a primary influence on NO3-N leaching. Shallow rooting depth (Strand, 1994), and sensitivity to soil salinity (Maas, 1984) and low soil water potential (Serrano et al., 1992), make efficient strawberry irrigation management challenging. Hanson and Bendixen (2004) found that seasonal irrigation applied to seven California strawberry fields ranged from underirrigation to a leaching fraction of 28%.
The primary objective of this study was to document plant and soil N dynamics in annual strawberry production under the environmental conditions and current grower management practices of the central coast region of California. Additionally, strawberry response to preplant CRF application rates was evaluated in three commercial field trials.
Albregts, E.E. & Chandler, C.K. 1993 Slow release fertilizer rates for strawberry fruit production Proc. Fla. State Hort. Soc. 106 187 189
Albregts, E.E. & Howard, C.M. 1980 Accumulation of nutrients by strawberry plants and fruit grown in annual hill culture J. Amer. Soc. Hort. Sci. 105 386 388
Albregts, E.E., Clark, G.A., Stanley, C.D., Zazueta, F.S. & Smajstrla, A.G. 1991b Preplant fertilization of fruiting microirrigated strawberry HortScience 26 1176 1177
Black, B.L., Hokanson, S.C. & Lewers, K.S. 2005 Fruit nitrogen content of sixteen strawberry genotypes grown in an advanced matted row production system HortScience 40 1190 1193
Bottoms, T.G., Smith, R.F., Cahn, M.D. & Hartz, T.K. 2012 Nitrogen requirements and N status determination of lettuce HortScience 47 1768 1774
Forster, J.C. 1995 Soil nitrogen, p. 79–87. In: Alef, K. and P. Nannipieri (eds.). Methods in applied soil microbiology and biochemistry. Academic Press, San Diego, CA
Grattan, S.R., Bowers, W., Dong, A., Snyder, R.L., Carroll, J.J. & George, W. 1998 New crop coefficients estimate water use of vegetables, row crops Calif. Agr. 52 16 21
Hart, Q.J., Brugnach, M., Temesgen, B., Rueda, C., Ustin, S.L. & Frame, K. 2009 Daily reference evapotranspiration for California using satellite imagery and weather station measurement interpolation Civ. Eng. Environ. Syst. 26 19 33
Hochmuth, G.J., Albregts, E.E., Chandler, C.C., Cornell, J. & Harrison, J. 1996 Nitrogen fertigation requirements of drip-irrigated strawberries J. Amer. Soc. Hort. Sci. 121 660 665
Kirschbaum, D.S., Borquez, A.M., Quipildor, S.L., Correa, M., Magen, H. & Imas, P. 2006 Nitrogen requirements of drip irrigated strawberries grown in subtropical environments Acta Hort. 708 93 96
Latet, G., Meesters, P. & Bries, J. 2002 The influence of different nitrogen (N) sources on the yield and leaching in open field strawberry production Acta Hort. 567 455 458
Locascio, S.J. & Martin, F.G. 1985 Nitrogen source and application timing for trickle irrigated strawberries J. Amer. Soc. Hort. Sci. 110 820 823
Locascio, S.J., Myers, J.M. & Martin, F.G. 1977 Frequency and rate of fertilization with trickle irrigation in strawberry J. Amer. Soc. Hort. Sci. 102 456 458
Maas, E.V. 1984 Salt tolerance of plants, p. 57–75. In: Christie, B.R. (ed.). Handbook of plant science in agriculture. CRC Press Inc., Boca Raton, FL
Miner, G.S., Poling, E.B., Carroll, D.E., Nelson, L.A. & Campbell, C.R. 1997 Influence of fall nitrogen and spring nitrogen–potassium applications on yield and fruit quality of ‘Chandler’ strawberry J. Amer. Soc. Hort. Sci. 122 290 295
Muramoto, J. & Gaskell, M. 2012 Nitrogen management for organic strawberries, p. 43–53. In: Koike, S.T., C.T. Bull, M.P. Bolda, and O. Daugovish (eds.). Organic strawberry production manual. Univ. of Calif. Publication 3531
Olsen, S.R. & Sommers, L.E. 1982 Phosphorus, p. 403–430. In: Page, A.L., R.H. Miller, and D.R. Keeney (eds.). Methods of soil analysis: Part 2. Chemical and microbiological properties. Monograph Number 9. American Society of Agronomy, Madison, WI
Prokopy, W.R. 1995 Phosphorus in 0.5 M sodium bicarbonate soil extracts. QuikChem Method 12-115-01-1-B. Lachat Instruments, Milwaukee, WI
Pruitt, W.D., Fereres, E. & Snyder, R.L. 1987. Reference evapotranspiration (ETo) for California. Univ. of Calif. Coop. Ext. Bul. 1922
Santos, B.M. & Chandler, C.K. 2009 Influence of nitrogen fertilization rates on the performance of strawberry cultivars Intl. J. Fruit Sci. 9 126 135
Serrano, L., Carbonell, X., Save, R., Marfa, O. & Penuelas, J. 1992 Effects of irrigation regimes on the yield and water use of strawberry Irrig. Sci. 13 45 48
Shaw, D.V. & Larson, K.D. 2008 Performance of early-generation and modern strawberry cultivars from the University of California breeding programme in growing systems simulating traditional and modern horticulture J. Hort. Sci. Biotechnol. 83 648 652
Sheldrick, B.H. & Wang, C. 1993 Particle size distribution, p. 499–511. In: Carter, M.R. (ed.). Soil sampling and methods of analysis. Canadian Society of Soil Science, Ottawa, Ontario, Canada
Strand, L.L. 1994. Integrated pest management for strawberries. Univ. of Calif. Publication 3351
Strik, B., Righetti, T. & Buller, G. 2004 Influence of rate, timing, and method of nitrogen fertilizer application on uptake and use of fertilizer nitrogen, growth, and yield of June-bearing strawberry J. Amer. Soc. Hort. Sci. 129 165 174
Tagliavini, M., Baldi, E., Lucchi, P., Antonelli, M., Sorrenti, G., Baruzzi, G. & Faedi, W. 2005 Dynamics of nutrient uptake by strawberry plants (Fragaria × Ananassa Dutch.) grown in soil and soilless culture Eur. J. Agron. 23 15 25
Tagliavini, M., Baldi, E., Nestby, R., Raynal-Lacroix, C., Lieten, P., Salo, T., Pivot, D., Lucchi, P.L., Baruzzi, G. & Faedi, W. 2004 Uptake and partitioning of major nutrients by strawberry plants Acta Hort. 640 197 200
Thomas, G.W. 1982 Exchangeable cations, p. 159–165. In: Page, A.L., R.H. Miller, and D.R. Keeney (eds.). Methods of soil analysis: Part 2. Chemical and microbiological properties. Monograph Number 9. American Society of Agronomy, Madison, WI
USDA, Economic Research Service 2012 U.S. strawberry industry. <http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1381>