Comparing soluble to controlled-release nitrogen fertilizers: storage cabbage yield, profit margins, and N use efficiency

Abstract

Optimizing N fertilizer applications involves maximizing N use efficiency (NUE) while minimizing losses but depends on complex interactions of crop, soil, weather, and management practices. One approach may be to use controlled-release fertilizer that synchronizes N availability with plant demand. A field experiment at two Ontario locations from 2007 to 2009 compared split-applied ammonium nitrate (ANs) to preplant-applied poly-coated urea (PCU) and soluble N at a ratio of 75:25 at five N rates on late-season storage cabbage (Brassica oleracea L. var. capitata). Maximum yield and profit margins were obtained at an average of 286 and >300 kg N ha−1, but few differences among sources were observed. Compared with ANs, PCU did not affect plant N content, nor did PCU reduce soil nitrate or NUE, which indicates little differences in risk of environmental N losses between N sources. Dissolution from mesh bags indicated 5%–25% of various PCU formulations remained by harvest but 5%–10% remained by spring, which suggests conservation over the winter, a need to synchronize N release with crop uptake, and partially explains the lack of treatment differences. From agronomic, economic, and environmental perspectives, the tested PCU treatments for cabbage production in a humid, temperate climate were equivalent to the standard practice.

Nitrogen Fertilizer Management and Cultivar Selection for Cabbage Production in the Southeastern United States

“…This result indicated that cabbage yields may be limited with 170 lb/acre N, but not with 225 lb/acre N, which was the fertilizer N rate required to sustain maximum yields. These results are corroborated with other studies reporting that the application of fertilizer rate of 170 lb/acre N can be increased to 225 lb/acre N in cabbage production areas under sandy soils (Bakker et al, 2009;McKeown et al, 2010;Van Eerd et al, 2017;Zebarth et al, 1991).…”

“…In the present study, when rainfall accumulation was similar or higher than the crop evapotranspiration (i.e., 2016 in Florida, 2018 in Georgia) or primarily occurred during the timing of fertilizer N applications (i.e., 2019 in Georgia), there were no significant effects of fertilizer N rates on cabbage yield. The absence of significant differences among fertilizer N rates in rainy periods after fertilizer application may be due to the movement of soil N below the root zone, which has been previously reported for cabbage production areas with sandy soils (Everaarts and Booi, 2000;Janes, 1950;Smith et al, 2016;Van Eerd et al, 2017). In contrast, the dry growing season in 2017 in Florida allowed for cabbage total and marketable yield to effectively increase under the fertilizer rates of 225 and 280 lb/acre N compared with the application of 170 lb/acre N. In this season, irrigation was the primary source of water for the crop; thereby, the effects of fertilizer applications were more pronounced during the 2017 season because irrigation was managed to reduce soil N leaching (Barrett et al, 2018).…”

“…Current cabbage N fertilizer recommendations for sandy soils in Florida and Georgia range from 150 to 225 lb/acre N, split into three or more applications (Granberry et al, 2017;Liu et al, 2019). For claytextured soils, a fertilizer rate of 143 lb/acre N has been reported to optimize cabbage yield (Khan et al, 2002); however, maximum cabbage yields in sandy soils are reported at a fertilizer rate of 255 lb/acre N, suggesting that the recommended rate of 170 lb/acre N is inadequate due to risks of N losses over rainy periods (Van Eerd et al, 2017). Recent studies conducted in sandy soils of northeast Florida reported an increase in cabbage yield with fertilization rates between 356 and 510 lb/ acre N, when cabbage was grown at high planting density (31,364 plant/ acre) in plastic mulch with drip irrigation (Barrett et al, 2018).…”

Nitrogen use efficiency and nitrous oxide emissions from five UK fertilised grasslands

“…It has major effects on the nutritive value of fresh herbage, as well as on animal nutrition and N balance (Lee, 2018). However, fertiliser rates exceeding crop requirements lead to an N surplus, reduced N use efficiency (NUE) and losses to the environment (Van Eerd et al, 2018). In terms of gaseous pollutants, N fertiliser applications are associated with emissions of nitrous oxide (N 2 O) (Reay et al, 2012), a powerful greenhouse gas (GHG) with a large global warming potential (Forster et al, 2007), and a gas that contributes to ozone (O 3 ) depletion in the stratosphere (Ravishankara et al, 2009).…”

Nano-Fertilization as an Emerging Fertilization Technique: Why Can Modern Agriculture Benefit from Its Use?

“…Thus, research regarding the use of nanoparticles (NPs) has gained attention among agricultural researchers in recent years [ 5 , 20 , 21 ]. In this context, there is a scientific curiosity for the production of novel sources of fertilizers with the aim of increasing fertilizer use efficiency [ 22 ]. From a sustainable agriculture perspective, nanotechnology has the potential to develop new innovative types of fertilizers such as nanofertilizers (NFs) to increase global food production to feed the increasing world population [ 7 , 21 , 23 ].…”