An analysis of the agronomic, economic and environmental effects of applying N fertilizer to sugarbeet (Beta vulgaris)

1996 ◽  
Vol 127 (4) ◽  
pp. 475-486 ◽  
Author(s):  
M. F. Allison ◽  
M. J. Armstrong ◽  
K. W. Jaggard ◽  
A. D. Todd ◽  
G. F. J. Milford

SUMMARYThe effects of different rates of N fertilizer (0–180 kg N/ha) were tested on the growth, yield and processing quality of sugarbeet in 34 field experiments in England between 1986 and 1988. The experiments were performed using soil types, locations and management systems that were representative of the commercial beet crop in the UK. The responses obtained showed that current recommendations for N fertilizer use are broadly correct, but large differences occurred on some soil types, in some years, between the recommended amounts and the experimentally determined optima for yield. The divergence was largest when organic manures had been applied in the autumn before the beet crop. Calculations using a simple nitrate-leaching model showed that much of the N in the manures was likely to be leached, the extent of leaching being much less if the manure application was delayed until spring. In these circumstances, spring measurement of inorganic mineral N in the soil could improve fertilizer recommendations. In situations where higher than optimum rates of fertilizer N were used, the extra N had little effect on yield. Increasing the rate from 0 to 180 kg N/ha increased the amount of nitrate left in the soil at harvest by only 8 kg N/ha. The amount of inorganic N released into the soil from crop residues at harvest increased by 50 kg N/ha with N application rate, and the fate of this N has not been established.

Agronomy ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 921
Author(s):  
Rania M. A. Nassar ◽  
Engy A. Seleem ◽  
Gianluca Caruso ◽  
Agnieszka Sekara ◽  
Magdi T. Abdelhamid

Egyptian henbane (Hyoscyamus muticus L.) plants are rich sources of alkaloids used in pharmaceutical products. Recently, rising efforts have been devoted to reducing mineral fertilizer supply, production cost, and environmental pollution via decreasing the doses of nitrogenous fertilizers and adopting biofertilizer farming systems. Two field experiments were conducted to examine the potential role of N fixing bacteria Azotobacter spp. and Azospirillum spp. on the growth, mineral status, tropane alkaloids, leaf anatomy, and seed yield of Egyptian henbane grown with different levels of mineral nitrogen fertilizer, i.e., 25%, 50%, and 100% of the recommended dose, equal to 30, 60, and 120 kg N ha−1. N fertilizer improved growth, mineral elements, tropane alkaloids, seed yield, and yield components of Egyptian henbane, which showed a gradually rising trend as the rate of N fertilizer increased. High doses of N fertilizer presumably elicited favorable changes in the anatomical structure of Egyptian henbane leaves. The application of 50% N dose plus N fixing bacteria affected Egyptian henbane trials similarly to 100% of recommended N dose. In conclusion, the N fixing bacteria proved to be a sustainable tool for a two-fold reduction in the recommended dose of mineral N fertilizer and the sustainable management of Egyptian henbane nutrition.


2016 ◽  
Vol 155 (2) ◽  
pp. 261-281 ◽  
Author(s):  
S. E. ROQUES ◽  
D. R. KINDRED ◽  
S. CLARKE

SUMMARYTriticale has a reputation for performing well on poor soils, under drought and with reduced inputs, but there has been little investigation of its performance on the better yielding soils dominated by wheat production. The present paper reports 16 field experiments comparing wheat and triticale yield responses to nitrogen (N) fertilizer on high-yielding soils in the UK in harvest years 2009–2014. Each experiment included at least two wheat and at least two triticale varieties, grown at five or six N fertilizer rates from 0 to at least 260 kg N/ha. Linear plus exponential curves were fitted to describe the yield response to N and to calculate economically optimal N rates. Normal type curves with depletion were used to describe protein responses to N. Whole crop samples from selected treatments were taken prior to harvest to measure crop biomass, harvest index, crop N content and yield components. At commercial N rates, mean triticale yield was higher than the mean wheat yield at 13 out of 16 sites; the mean yield advantage of triticale was 0·53 t/ha in the first cereal position and 1·26 t/ha in the second cereal position. Optimal N requirement varied with variety at ten of the 16 sites, but there was no consistent difference between the optimal N rates of wheat and triticale. Triticale grain had lower protein content and lower specific weight than wheat grain. Triticale typically showed higher biomass and straw yields, lower harvest index and higher total N uptake than wheat. Consequently, triticale had higher N uptake efficiency and higher N use efficiency. Based on this study, current N fertilizer recommendations for triticale in the UK are too low, as are national statistics and expectations of triticale yields. The implications of these findings for arable cropping and cereals markets in the UK and Northern Europe are discussed, and the changes which would need to occur to allow triticale to fulfil a role in achieving sustainable intensification are explored.


1995 ◽  
Vol 125 (1) ◽  
pp. 61-68 ◽  
Author(s):  
M. F. Allison ◽  
H. M. Hetschkun

SUMMARYIn 1990–92, field experiments were performed at Broom's Barn Experimental Station to study the effect of 5 years' repeated straw incorporation on sugarbeet. Straw incorporation had no effect on plant population density. Processing quality was reduced by incorporated straw but N had a much larger effect. The effect of incorporated straw on the mineral N content of the soils and N uptake by beet was inconsistent, and this may be related to the amount of soil mineral N present when the straw was incorporated. The efficiency of fertilizer use was unaffected by straw incorporation. On Broom's Barn soils when straw was incorporated, the optimal economic N dressing was c. 120 kg N/ha, and in unincorporated plots it was c. 100 kg N/ha. At the optimal economic N rate, incorporated straw increased beet yields.


1991 ◽  
Vol 117 (2) ◽  
pp. 241-249 ◽  
Author(s):  
T. M. Addiscott ◽  
R. J. Darby

SUMMARYOptimum applications of N fertilizer, Nopt have been related successfully to the amount of mineral N in the soil, Nmin in some parts of Europe but not always in the UK. If there is a body of mineral N, QN, that ultimately lessens the need for N fertilizer, it will not remain constant in its amount or its position. Mineralization will add to QN, while the nitrate component of QN will be leached downwards.Also, part of QN will be taken up into the crop where it will continue to lessen the need for fertilizer N but will be safe from leaching. A computer model was used to simulate these processes for 23 experiments, covering five sites and five years, in which N opt had been estimated. From these simulations we derived trial values of QN that took account of mineral N to a series of depths on a series of dates. For each date we used the trial values to find the depth for which Nopt was best correlated with QN andassumed that this was the depth, dL, of the lower boundary of QN on that date. Thus dL was a collective value for all 23 experiments. The value of dLincreased throughout the winter and the spring and was very closely related to the cumulative average drainage through 0·5 m soil at Rothamsted. By 15 April, dL, was 1·66 m, a depth that was compatible with observations by others that winter wheat can remove mineral N to a depth of at least 1·5 m. We inferred two likely reasons why Nmin may fail as a predictor of Nopt in the UK: insufficient depth of sampling, and too wide a spread of sampling dates. The values of Nopt were shown to be related satisfactorily to the values of QN computed, without any measurements of mineral N, for appropriate depths on single dates.


2011 ◽  
Vol 49 (No. 4) ◽  
pp. 163-167 ◽  
Author(s):  
F. Bavec ◽  
B. Čeh Brežnik ◽  
M. Brežnik

Numerous agricultural and associated ecological effects such as mineral nitrogen fertilising influence the yield of hop (Humulus lupulus L.) cones and its quality. Using a wide spacing of plants (in our case 2.6 × 0.8 m) we want to answer a hypothetical question about an appropriate number of test plants per plot vs. experimental plot area. The aim of this study was to compare the effect of different rates of mineral nitrogen, fertiliser combinations and their nitrogen split application on hop yield evaluated from different plot areas (micro trial: 30 plants per plot; macro trial: 320 plants per plot). Hop yield varied significantly between treatments, plot areas, years and interactions (year × treatment, plot area × treatment) (all at P £ 0.01). Cone yield in a micro trial was higher in all treatments in comparison with yield in a macro trial. In spite of common intensive fertilisation the appropriate fertilising combination and mineral N rate can influence the yield. Target nitrogen rate of160 kg mineral N/ha (at the level from 40.0 to62.5 kg nitrate N/ha in soil depth to0.3 m) and cheaper combination of calcium-ammonium nitrate (50 kg N/ha) at the beginning of vegetation plus urea (110 kg N/ha) for top dressing can be recommended. On plot areas of each size and each year all treatments showed similar trends of fertilising effect on yield. In spite of higher yield in the micro trial and lower coefficient of variation in comparison with the macro trial, the results proved that a risk of incorrect yield analysing in macro trials is very low for field experiments.


1988 ◽  
Vol 36 (4) ◽  
pp. 375-385
Author(s):  
W.J.M. Meijer ◽  
S. Vreeke

The relationship between the level of soil mineral N present in early spring and the economically optimum application rate of N fertilizer was investigated in field experiments in 1978-84 at 4 locations in the Netherlands with Lolium perenne, Poa pratensis and Festuca rubra. Spring dressings, as split and single applications, of 30-210 kg N/ha and autumn dressings of 0-90 kg N/ha were used. The optimum spring rates were linearly related to mineral N in the 0-90 cm soil layers in L. perenne. No such relationship existed for the other species. The economically optimum spring N rates were 110 and 84 kg/ha, and yields were highest with autumn N dressings of 60 and 30 kg/ha for P. pratensis and F. rubra, resp. Autumn dressing had no effect on L. perenne if the spring dressing was near or above the optimum. A split spring dressing produced greater vegetative regrowth and reduced yields. Seed yield responses to fertilization were related to number of inflorescences produced rather than weight of seed per inflorescence. (Abstract retrieved from CAB Abstracts by CABI’s permission)


2001 ◽  
Vol 1 ◽  
pp. 320-327
Author(s):  
M.I. Khalil ◽  
A.B. Rosenani ◽  
O. Van Cleemput ◽  
C.I. Fauziah ◽  
J. Shamshuddin

Development of appropriate land management techniques to attain sustainability and increase the N use efficiency of crops in the tropics has been gaining momentum. The nitrous oxides (N2Os) affect global climate change and its contribution from N and C management systems is of great significance. Thus, N transformations and N2O emission during maize-groundnut crop rotation managed with various N sources were studied. Accumulation of nitrate (NO3 –) and its disappearance happened immediately after addition of various N sources, showing liming effect. The mineral N retained for 2–4 weeks depending on the type and amount of N application. The chicken manure showed rapid nitrification in the first week after application during the fallow period, leading to a maximum N2O flux of 9889 μg N2O-N m–2 day– 1. The same plots showed a residual effect by emitting the highest N2O (4053 μg N2O-N m–2 day– 1) during maize cultivation supplied with a halfrate of N fertilizer. Application of N fertilizer only or in combination with crop residues exhibited either lowered fluxes or caused a sink during the groundnut and fallow periods due to small availability of substrates and/or low water-filled pore space (<40%). The annual N2O emission ranged from 1.41 to 3.94 kg N2O-N ha–1; the highest was estimated from the chicken manure plus crop residues and half-rate of inorganic N-amended plots. Results indicates a greater influence of chicken manure on the N transformations and thereby N2O emission.


Author(s):  
Letusa Momesso ◽  
Carlos A. C. Crusciol ◽  
Rogério P. Soratto ◽  
Carlos A. C. Nascimento ◽  
Ciro A. Rosolem ◽  
...  

AbstractOptimizing agronomic efficiency (AE) of nitrogen (N) fertilizer use by crops and enhancing crop yields are challenges for tropical no-tillage systems since maintaining crop residues on the soil surface alters the nutrient supply to the system. Cover crops receiving N fertilizer can provide superior biomass, N cycling to the soil and plant residue mineralization. The aims of this study were to (i) investigate N application on forage cover crops or cover crop residues as a substitute for N sidedressing (conventional method) for maize and (ii) investigate the supply of mineral N in the soil and the rates of biomass decomposition and N release. The treatments comprised two species, i.e., palisade grass [Urochloa brizantha (Hochst. Ex A. Rich.) R.D. Webster] and ruzigrass [Urochloa ruziziensis (R. Germ. and C.M. Evrard) Crins], and four N applications: (i) control (no N application), (ii) on live cover crops 35 days before maize seeding (35 DBS), (iii) on cover crop residues 1 DBS, and (iv) conventional method (N sidedressing of maize). The maximum rates of biomass decomposition and N release were in palisade grass. The biomass of palisade grass and ruzigrass were 81 and 47% higher in N application at 35 DBS compared with control in ruzigrass (7 Mg ha−1), and N release followed the pattern observed of biomass in palisade and ruzigrass receiving N 35 DBS (249 and 189 kg N ha−1). Mineral N in the soil increased with N application regardless of cover crop species. Maize grain yields and AE were not affected when N was applied on palisade grass 35 DBS or 1 DBS (average 13 Mg ha−1 and 54 kg N kg−1 maize grain yield) compared to conventional method. However, N applied on ruzigrass 35 DBS decreased maize grain yields. Overall, N fertilizer can be applied on palisade grass 35 DBS or its residues 1 DBS as a substitute for conventional sidedressing application for maize.


1998 ◽  
Vol 46 (2) ◽  
pp. 139-155 ◽  
Author(s):  
W. Van Dijk ◽  
G. Brouwer

In 1991-94 the effects of subsurface band application of mineral N fertilizer on the N recovery and dry matter (DM) yield of silage maize were studied in nine field experiments on sandy and clay soils in the Netherlands. In the early crop stages and especially in the clay soil experiments, banded N had a significant negative effect on the N uptake and DM yield compared to broadcast N, possibly due to salt damage. At final harvest, however, banding significantly increased the N uptake and DM yield in most of the experiments. The apparent N recovery increased by circa 20-25% (absolute). The positive effects indicated that band application improved the efficiency of the N fertilizer. It could be calculated that banding allowed a reduction in the N rate of 20-30% without significant effects on the N uptake and DM yield of the silage maize. Benefits of banding were positively (P


2002 ◽  
pp. 41-46
Author(s):  
Gheorghe Ciobanu ◽  
Cornelia Ciobanu ◽  
Cornel Domuta ◽  
Nicolae Csep ◽  
Petru Burescu

Nitrogen fertilizer represents major economic burden. For this reason, although the efficiency of nitrogen utilization varies highly, its actual use generally remains at low levels; these averaging between 25 and 50%. We set up an experiment at the Oradea Research Station, using 15N labeled fertilizers, in order to investigate the possibility of increasing N fertilizer efficiency in winter wheat under irrigation conditions.Fertilizers labeled with 15N allows us to individually determine its effect on yield formation, as well as the use efficiency of N from fertilizer following application rate and time. The amount of N derived from fertilizer as determined in straw and grain yield is high. When the labeled fertilizer is applied at tillering time, the values of this indicator rise when higher N levels we applied.In separate experiments, we investigated a series of aspects connected to chemical fertilizer regarding the determination of the type of fertilizer, optimum time and rates of application; all these as a function of the special pedoclimatic conditions.The results obtained in the field show that the effectiveness of N utilization in wheat is most variable and generally low, often ranging between 25 and 33%, owing to N loss within the system through leaching and NH3 volatilization.A readily achievable increase in efficiency of 5 percentage points would result in considerable savings, and can be brought about by reducing nitrogen losses. The added benefits to the environment in terms of reduced ground/water contamination and lowered nitrous oxide (N20) emissions would also be substantial.The figures for N fertilizer use efficiency (% N range from 35.5 to 72.6, the highest value being recorded with an N application of 120 kg/ha at tillering, when the previous crop was sunflower).INTRODUCTION


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