Response of Highbush Blueberry to Nitrogen Fertilizer During Field Establishment, I: Accumulation and Allocation of Fertilizer Nitrogen and Biomass

Abstract

<jats:p>The effects of nitrogen (N) fertilizer application on plant growth, N uptake, and biomass and N allocation in highbush blueberry (<jats:italic>Vaccinium corymbosum</jats:italic> L. ‘Bluecrop’) were determined during the first 2 years of field establishment. Plants were either grown without N fertilizer after planting (0N) or were fertilized with 50, 100, or 150 kg·ha<jats:sup>−1</jats:sup> of N (50N, 100N, 150N, respectively) per year using <jats:sup>15</jats:sup>N-depleted ammonium sulfate the first year (2002) and non-labeled ammonium sulfate the second year (2003) and were destructively harvested on 11 dates from Mar. 2002 to Jan. 2004. Application of 50N produced the most growth and yield among the N fertilizer treatments, whereas application of 100N and 150N reduced total plant dry weight (DW) and relative uptake of N fertilizer and resulted in 17% to 55% plant mortality. By the end of the first growing season in Oct. 2002, plants fertilized with 50N, 100N, and 150N recovered 17%, 10%, and 3% of the total N applied, respectively. The top-to-root DW ratio was 1.2, 1.6, 2.1, and 1.5 for the 0N, 50N, 100N, and 150N treatments, respectively. By Feb. 2003, 0N plants gained 1.6 g/plant of N from soil and pre-plant N sources, whereas fertilized plants accumulated only 0.9 g/plant of N from these sources and took up an average of 1.4 g/plant of N from the fertilizer. In Year 2, total N and dry matter increased from harvest to dormancy in 0N plants but decreased in N-fertilized plants. Plants grown with 0N also allocated less biomass to leaves and fruit than fertilized plants and therefore lost less DW and N during leaf abscission, pruning, and fruit harvest. Consequently, by Jan. 2004, there was little difference in DW between 0N and 50N treatments; however, as a result of lower N concentrations, 0N plants accumulated only 3.6 g/plant (9.6 kg·ha<jats:sup>−1</jats:sup>) of N, whereas plants fertilized with 50N accumulated 6.4 g/plant (17.8 kg·ha<jats:sup>−1</jats:sup>), 20% of which came from <jats:sup>15</jats:sup>N fertilizer applied in 2002. Although fertilizer N applied in 2002 was diluted by non-labeled N applications the next year, total N derived from the fertilizer (NDFF) almost doubled during the second season, before post-harvest losses brought it back to the starting point.</jats:p>

Effects of nitrogen rate and application method on early production and fruit quality in highbush blueberry

“…Applications greater than 34 kg N ha (1 likewise did not increase yield any further in young blueberry plants in New Jersey, and rates !64 kg N ha (1 were detrimental to early fruit production (Eck 1977). Similar detrimental effects have been observed on growth of young blueberry plants in western Oregon (Ban˜ados et al 2012). In another western Oregon study, Bryla and Machado (2011) found that granular ammonium sulphate applications maximized growth in young 'Bluecrop' blueberry plants at 50 kg N ha (1 or less and reduced growth at 100Á150 kg N ha (1 .…”

“…Fertigation also enables more precise control over fertilizer composition, which can be easily changed throughout the growing season, depending on plant requirements as determined by foliar analysis. When granular N fertilizer is applied to blueberry, N uptake is fairly constant throughout the growing season in young, uncropped plants, but greater during peaks in vegetative growth in the spring and during fruit development in early summer than after harvest in fruiting plants (Throop and Hanson 1997;Ban˜ados et al 2012). There is no published information available on N uptake by fertigated blueberry plants.…”

Seasonal Variation in Leaf Nutrient Concentration of Northern Highbush Blueberry Cultivars Grown in Conventional and Organic Production Systems

“…Even though leaf N was significantly lower in 2013 than in 2014 at both sites, it was barely below current sufficiency levels only at the organic site (Table 6). Leaf N may have increased at the conventional site as more N fertilizer was applied in 2014 (Table 1), since leaf N is positively correlated with fertilization rate in blueberry (Bañados et al, 2012;Retamales and Hanson, 1990;Spiers, 1983). There was no cultivar effect on leaf N at the organic site, whereas 'Draper' had a higher leaf N than all other cultivars at the conventional site.…”

Groundwater Monitoring to Support Development of BMPs for Groundwater Protection: The Abbotsford‐Sumas Aquifer Case Study

“…Precision management in other woody species has attempted to limit supplementary N applications to the times when remobilization and soil supply cannot meet demand (Neilsen and Neilsen ; Bańados et al ), often in spring after the first leaves have emerged, when soil temperatures limit soil N mineralization. The most efficient method of applying N to the root zone is through the irrigation system (i.e., fertigation) (Bar‐Josef ; Neilsen et al ; Neilsen and Neilsen ; Tagliavini and Marangoni ) at high frequency (Silber et al ).…”

“…Fall planting of annual cover crops is a recommended practice in BC (BCMA ). Annual cover crops of cereal rye or barley planted in late summer or early fall did not suppress raspberry growth (Freyman ; Zebarth et al ; Bowen and Freyman ) and took up residual nitrate from the soil root zone, preventing it from being leached by autumn and winter rainfall (Zebarth et al ).…”