Characterizing Early-Season Nitrogen Fertilization Rate Effects on Growth, Yield, and Quality of Strawberry

Abstract

In winter strawberry (Fragaria × ananassa Duch.) production, early-season nitrogen (N) fertilization greatly affects fruit earliness and yields, especially when pre-plant N is not applied. The objective of this study was to characterize the dose-responses of canopy growth, yield, and fruit quality to early-season N fertilization in ‘Florida Radiance’ and ‘Florida127’ strawberry. Field experiments were conducted in west-central Florida, United States. Treatments included four (0.56, 0.84, 1.12 and 1.40 kg ha−1 d−1) and five (0.22, 0.67, 1.12, 1.57, and 2.02 kg ha−1 d−1) early-season N rates in the first and second growing seasons, respectively. Increasing the early-season N rate increased early and total season yields by up to 62% to 65% and 56% to 58%, respectively, in the two cultivars. The total season yield had high positive correlations with leaf area and shoot DW. Model fitting analysis revealed cultivar-dependent dose-responses. Yield and berry size responses in ‘Florida Radiance’ were linear increases, whereas those in ‘Florida127’ were quadratic with peaks occurring at N rates of 1.21 or 1.57 kg ha−1 d−1. In ‘Florida Radiance’, soluble solids concentration showed a linear dose-response with a slope of –0.91 (0.91 °Brix decrease per 1 kg ha−1 d−1 N increase) during the early season. These results suggest that optimization of early-season N fertilization is an important production strategy to improve the profitability of winter strawberry production. Furthermore, fertilizer management that takes into account cultivar-dependent dose-responses can improve fertilizer use efficiency while minimizing fruit quality loss and environmental pollution risks.

The Application of Nitrogen Fertilization and Foliar Spraying with Calcium and Boron Affects Growth Aspects, Chemical Composition, Productivity and Fruit Quality of Strawberry Plants

“…Contrasting reports in the literature refer to the effect of N fertilization on the total soluble solids content. While Weber et al [32] and Ojeda-Real et al [49] did not observe significant effects of increasing N rates, Agehara [31] reported a linear decrease in soluble solids content with increasing N rates up to 192 kg/ha. On the other hand, Khalil and Agah [35] and Hassan [33] reported that the combined application of mineral, organic and biofertilizers improved the TSS content over the mineral fertilization.…”

“…The improvement in plant growth, due to the combined supplementation of mineral and organic N could be attributed to the slow release of N in organic fertilizers, which may better fulfill the plant requirements during the later stages of the growing season, while mineral fertilizers can compensate for the needed N in early to mid-stages, due to the presence of both nitrates and ammonium N in the tested mineral fertilizer. According to Agehara [31], the early season applications of N increased significantly early and total fruit yield, due to larger leaf area and higher shoot dry weight. Besides, organic fertilizers play a vital role in improving soil physical properties and reducing pH value which affects the availability and uptaking of soil nutrients from plants and consequently improves plant growth parameters [32].…”

“…The highest total yield per ha and per plant and exportable yield in case of fertilization using half of the recommended dose of N as mineral and other as compost may be attributed to the balanced availability of N throughout the growing period. According to the literature, N application rates, as well as N form, may affect the total yield and number of fruits per plant [33,42], while the time of application is also important, since the improved vegetative growth (high leaf area and shoot dry matter) is also associated with increased yield [31]. Moreover, N availability in perennial crops, such as strawberry, is essential after the renovation period.…”

“…Regarding the total sugars content, Ojeda-Real et al [49] reported decreasing trends with increasing N application rates which contrasts with our findings. Agehara [31] also suggested that the reduced total sugars content recorded in fruit from plants treated with increased N rates could be attributed to the partitioning of sugars to a higher number of fruits or to a dilution effect, due to the increase of fruit size.…”

Influence of Organic and Inorganic Fertilizer Regimes on Growth Patterns and Antioxidants Capacity of Strawberry (Fragaria × Ananassa Duch.) cv. Chandler

“…Strawberries have a large harvest window with intensive nutrient uptake, which results in depletion of soil fertility [11]. Availability of nitrogen is the most important factor for its production and fruit quality [12]. In effect, vegetables and fruit produced with sufficient availability of nutrients contain a high level of total phenols, flavonoids, organic acids, sugars, and L -ascorbic acid [13].…”