Corn Yield Response to Managed Drainage and Polymer-Coated Urea

Polymer coated urea (PCU) have the potential to increase nitrogen (N) use efficiency (NUE) by the release of N following crop demand while reducing losses by volatilization, leaching and denitrification. However, the NUE of PCU is still unclear especially in systems of corn-palisadegrass intercropping. Broadcast application of urea result in ammonia volatilization losses, new technologies must be adopted in order to allow broadcast application of urea. The aim of this research was to evaluate NUE from PCU in the corn-palisadegrass intercropping system and the viability of the broadcast application using PCU. Two field trials were carried out in a 4 × 2 factorial design including fertilization treatments and application forms. Fertilization treatments were: Conventional Urea topdressing (CUT); Conventional Urea at corn planting (CUP); PCU applied at planting to release in 30 days (PCU30); PCU mixture applied at planting to release in 30 and 60 days (PCU30+60); and application forms: broadcast placement and in furrow. 15N-urea was used for the determination of NUE. The corn yield and palisadegrass above-ground biomass were not affected by the fertilization treatments or application forms. PCU did not increase N uptake and the NUE by corn or palisadegrass in relation to urea. The N uptake from fertilizer by palisadegrass intercropped with corn is less than 1% of all N uptake on the intercropping system and at most 2% of the N fertilizer applied. The slow release urea does not enable the broadcast application and its efficiency depended upon the same climatic conditions as those of the conventional urea.

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Yield Response of Upland Rice as Influenced by Enhanced-Efficiency Nitrogen Fertilizers in the Brazilian Cerrado

Journal of Agricultural Science ◽

10.5539/jas.v12n11p98 ◽

2020 ◽

Vol 12 (11) ◽

pp. 98

Author(s):

Vinícius Almeida Oliveira ◽

Eliana Paula Fernandes Brasil ◽

Welldy Gonçalves Teixeira ◽

Felipe Corrêa Veloso dos Santos ◽

Atila Reis da Silva

Keyword(s):

Upland Rice ◽

Block Design ◽

Fertilizer Application ◽

Nitrogen Fertilizers ◽

Control Treatment ◽

Yield Response ◽

Randomized Block Design ◽

Coated Urea ◽

Set Up ◽

Polymer Coated Urea

Nitrogen (N) fertilizers have their use efficiency adversely affected by the rate and source of N. A two-year field experiment was conducted to examine the yield response of upland rice by using NBPT (urease inhibitor), PCU (polymer-coated urea) and uncoated urea under different N application rates. It was hypothesized that either NPBT or PCU may result in increased yield components of upland rice when compared to conventional urea. The experiment was set up in a randomized block design in a 3 × 4 + 1 factorial scheme, with four replicates. Treatments comprised three sources (conventional uncoated urea, NBPT-treated urea, and polymer-coated urea) and four rates (30, 60, 90 and 120 kg ha-1) of N, in addition to a control treatment (no fertilizer application). Nitrogen fertilizers were applied in two split doses: 50% at the seedling stage, and 50% at the tillering stage (~80 days after planting). The results revealed that the use of enhanced-efficiency N sources increased the productivity and plant height of upland rice crop when compared to conventional urea. As compared to when it is untreated or polymner-coated, treating urea with NBPT resulted in increased 100-grain weight.

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Yield and chlorophyll index in cabbage in function of enhanced-efficiency nitrogen fertilizers and urea

Scientific Electronic Archives ◽

10.36560/1312020997 ◽

2020 ◽

Vol 13 (2) ◽

pp. 6

Author(s):

J. J. Frazão ◽

A. R. Silva ◽

F. H. M. Salgado ◽

R. A. Flores ◽

E. P. F. Brasil

Keyword(s):

Nitrogen Fertilizers ◽

N Losses ◽

N Sources ◽

Promising Strategy ◽

Applied Dose ◽

Coated Urea ◽

Chlorophyll Index ◽

Polymer Coated Urea ◽

N Rates ◽

And Control

The increase of the efficiency of the nitrogen fertilization promotes reduction of the applied dose and decreases the losses of nitrogen (N) to the environment. The objective of this work was to evaluate the yield and the relative chlorophyll index (IRC) in cabbage crop under cover fertilization, using enhanced-efficiency nitrogen fertilizers, compared to urea, in variable doses. The experimental design was randomized blocks in a 3x4+1 factorial scheme (three sources, four rates and control), with four replications. The N sources used were: common urea (U), urea treated with urease inhibitor NBPT® (UN) and Kimcoat® polymer coated urea (UK). The N rates used were 0, 40, 80, 160 and 320 kg ha-1, divided in two fertilizations at 20 and 40 days after transplantation. Up to 160 kg ha-1 of N, there was no difference between N sources and N rates for both yield and RCI. The enhanced-efficiency N sources (UN and UK) promoted higher averages compared to common urea, possibly due to the higher N losses from common urea. Thus, the use of urease inhibitors or polymers associated with urea is a promising strategy to improve cabbage yield, as well as reducing N losses to the environment.

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Corn Yield Response to some Irrigation Methods and Fertilization with Macro and Micronutrients

Egyptian Journal of Soil Science ◽

10.21608/ejss.2013.172 ◽

2013 ◽

Vol 53 (3) ◽

pp. 347-360 ◽

Cited By ~ 1

Keyword(s):

Yield Response ◽

Corn Yield ◽

Irrigation Methods ◽

Macro And Micronutrients

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Nitrogen Recovery from Enhanced Efficiency Fertilizers and Urea in Intensively Managed Black Walnut (Juglans nigra) Plantations

Forests ◽

10.3390/f12030352 ◽

2021 ◽

Vol 12 (3) ◽

pp. 352

Author(s):

Joshua L. Sloan ◽

Francis K. Salifu ◽

Douglass F. Jacobs

Keyword(s):

Black Walnut ◽

Juglans Nigra ◽

Water Soluble ◽

Growth And Yield ◽

N Recovery ◽

Competing Vegetation ◽

Fertilizer N Recovery ◽

Coated Urea ◽

Intensively Managed ◽

Polymer Coated Urea

Intensively managed forest plantations often require fertilization to maintain site fertility and to improve growth and yield over successive rotations. We applied urea-based “enhanced-efficiency fertilizers” (EEF) containing 0.5 atom% 15N at a rate of 224 kg N ha−1 to soils under mid-rotation black walnut (Juglans nigra L.) plantations to track the fate of applied 15N within aboveground ecosystem components during the 12-month period after application. Treatments included Agrotain Ultra (urea coated with a urease inhibitor), Arborite EC (urea coated with water-soluble boron and phosphate), Agrium ESN (polymer-coated urea), uncoated urea, and an unfertilized control. Agrotain Ultra and Arborite EC increased N concentrations of competing vegetation within one month after fertilization, while neither Agrium ESN nor uncoated urea had any effect on competing vegetation N concentrations during the experiment. Agrotain Ultra and Arborite EC increased δ15N values in leaves of crop trees above those of controls at one and two months after fertilization, respectively. By contrast, Agrium ESN and uncoated urea had no effect on δ15N values in leaves of crop trees until three months after fertilization. Fertilizer N recovery (FNR) varied among ecosystem components, with competing vegetation acting as a sink for applied nutrients. There were no significant differences in FNR for all the urea-based EEF products compared to uncoated urea. Agrium ESN was the only EEF that exhibited controlled-release activity in this study, with other fertilizers behaving similarly to uncoated urea.

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