RESPONSE OF BROMEGRASS TO N, P AND S FERTILIZER ON A GRAY LUVISOLIC SOIL IN NORTHWESTERN SASKATCHEWAN

1988 ◽  
Vol 68 (3) ◽  
pp. 687-703 ◽  
Author(s):  
H. UKRAINETZ ◽  
C. A. CAMPBELL ◽  
R. P. ZENTNER ◽  
M. MONREAL

A 9-yr study was conducted on a Gray Luvisolic loam at Loon Lake, Saskatchewan to determine the effect of ammonium nitrate-N (34–0–0) and urea-N (46–0–0) on bromegrass (Bromus inermis Leyss.) production and nutrient quality, N recovery, and N use efficiency when the N was applied either annually or as a single application at the start of the experiment. The effects of phosphorus (P) and sulphur (S) were also assessed. Each N source was applied at single rates of 0, 100, 200, 400 and 800 kg ha−1 N and annual rates of 0, 50, 100 and 200 kg ha−1 N. The ammonium nitrate was also applied as a single dose at rates of 600 and 1000 kg ha−1 N. Phosphorus and S were applied every second year at 224 kg ha−1 P2O5 and 45 kg ha−1 S. Forage dry matter yields were positively related to precipitation received in May and July, and April–May, but negatively related to June precipitation. Forage dry matter production was greater over the first 8-yr period for annual N applications than for a single application receiving an equivalent amount of N; but fertilizer N recovered in forage over the same period was similar (about 30%) for the two methods of application. Dry matter yields were 19% greater after 4 yr and 26% greater after 8 yr when ammonium nitrate was used compared to urea. Recovery of fertilizer N in forage also favored the ammonium nitrate source. The application of low to moderate N rates depressed forage N and P concentrations when yield response was high but concentrations were increased by the highest rates of N fertilizer and by repeated annual applications of N. Toxic concentrations of NO3-N occurred in bromegrass in the first year when N was applied at or above 400 kg ha−1 as one application and also in the second year when N was applied at 800 kg ha−1. When N was applied annually at 200 kg ha−1, NO3-toxicity became a potential problem in later years as soil mineral N accumulated. Phosphorus and S fertilizers increased dry matter yields of forage; P fertilizer increased and S decreased forage P concentration. Annual N applications resulted in more uniform year-to-year yields and N uptake response compared to a single application and provided greater dry matter production without loss of nutritive quality. It was concluded that, in contrast to reports in the literature, the response of forage grasses to N is not site specific.Key words: N source, N recovery, N application method, N use efficiency, phosphorus, sulfur

1988 ◽  
Vol 68 (2) ◽  
pp. 457-470 ◽  
Author(s):  
H. UKRAINETZ ◽  
C. A. CAMPBELL

A 5–yr study was conducted on a Dark Brown loam at Scott, Saskatchewan to determine the effect of rate of ammonium nitrate-N (34–0–0) and urea-N (46–0–0) on bromegrass (Bromus inermis Leyss.) production and quality, N recovery and N use efficiency when the N was applied either annually or as a single application at the start of the experiment. The effect of phosphorus (P) on the above listed parameters was also assessed. Each N source was applied at once-only rates of 0, 100, 200, 400, and 800 kg ha−1 and annual rates were 0, 50, 100 and 200 kg ha−1. Phosphorus was applied in 1976, 1979 and 1981 at 100 kg ha−1 P2O5. Forage dry matter was positively related to precipitation received in April–June (r = 0.91**) and in April of the crop year plus the previous September (r = 0.80**). Dry matter response to N rates generally increased at a decreasing rate in early years but linearly in later years. Over the first 4 yr, annual applications of N resulted in up to 37% more dry matter than the single applications. Dry matter production was generally greater when ammonium nitrate was applied than when urea was used; these differences were more consistent at medium N rates. Dry matter was increased by P only when N was applied. Nitrogen concentration in forage was directly related to N rate in years of good precipitation, was greater in dry than wet years, and when N was applied annually, but was unaffected by N source. Phosphorus fertilization increased P concentration of forage but heavy dry matter production reduced P concentration. Annual N applications increased P concentration in forage only in the first year and N source had no effect. Toxic concentrations of NO3–N in the forage occurred in the first year only at N rates [Formula: see text] and were directly related to the amount of N applied. Except for the 800 kg ha−1 N rate in the second year, there were no further indications of NO3–N toxicity. Accumulated N use efficiency decreased linearly with increasing N rate and was greater for ammonium nitrate than for urea except at very high N rates. Accumulated N recovery was inversely related to N rate for the single method of application but unaffected by N rate applied annually. Over the first 4 yr, accumulated N recovery was greater for the single application at low N rates, but was greater for annual applications of N at high N rates. P fertilization increased N recovery.Key words: N source, bromegrass, N recovery, yield, quality, application method


2002 ◽  
Vol 139 (1) ◽  
pp. 11-25 ◽  
Author(s):  
R. J. READMAN ◽  
C. P. BECKWITH ◽  
P. S. KETTLEWELL

A field experiment was carried out at Harper Adams in Shropshire to investigate the effect of supplying the spring N application to winter wheat as different proportions of urea as a solution, rather than as conventional soil-applied solid urea, on N recovery in the above-ground crop, autumn soil mineral N and nitrate leaching over the subsequent winter. A solid ammonium nitrate treatment was also included to represent alternative commercial practice to solid urea. Treatments were repeated on the same plots over the 3 years 1992, 1993 and 1994. N recovery was measured in all 3 years by difference in N uptake between fertilized and unfertilized plots, and in 1993 for selected treatments, N was applied as 15N-labelled fertilizer to determine direct uptake of fertilizer N in the crop and soil. Both urea sprays and solid soil N applications were labelled with 15N. Urea sprays were split over several days to reduce scorch, whereas solid fertilizer was applied as a single dressing. For some urea spray treatments, apparent N recovery in the above-ground crop in 1992 and 1994 was less compared with soil-applied N treatments. These urea spray treatments were applied in the morning rather than the evening, and gaseous losses, most likely by volatilization, are suggested. In 1992 application of a large proportion of N as urea sprays, such that application of some N as urea solution was delayed to around GS 37, was associated with an increase in physiological N use efficiency. In 1993, there was no difference in direct or apparent recovery of fertilizer N in the crop or soil for N applied as ammonium nitrate, solid urea or as urea sprays. Mean nitrate concentration in the drainage water at 1 m was elevated for all N treatments in all years, but only in 1992 did nitrate concentration and leaching loss decrease with increasing proportion of N applied as urea sprays. It may therefore be possible to reduce gaseous losses by application of urea sprays under cool conditions in the evening and exploit the increased physiological N use efficiency for urea sprays applied later, such that total fertilizer N applied and N losses are reduced.


1995 ◽  
Vol 87 (2) ◽  
pp. 193-199 ◽  
Author(s):  
Karl Guillard ◽  
Gary F. Griffin ◽  
Derek W. Allinson ◽  
M. Moosa Rafey ◽  
William R. Yamartino ◽  
...  

1983 ◽  
Vol 63 (4) ◽  
pp. 719-725 ◽  
Author(s):  
A. A. BOMKE ◽  
R. A. BERTRAND

Urea and ammonium nitrate were applied at rates of 75, 150 and 300 kg N/ha as either a single application in April or split into three equal increments, one applied in April and the second and third following cuts one and two. The orchardgrass-perennial ryegrass sward responded significantly to applied N in each year; however, the yield produced by the two sources differed in only one of the three years. In that year split applied ammonium nitrate gave 8% higher yields than similarly applied urea. The sources were found to be equivalent when applied in the spring. Split application of the N rates increased total annual dry matter yields in one of the three years regardless of N source. In all three years split application of N shifted forage production from cut one to cuts two and three. Key words: N uptake, split N application, orchardgrass-perennial ryegrass sward


2004 ◽  
Vol 84 (3) ◽  
pp. 845-854 ◽  
Author(s):  
B. J. Zebarth ◽  
Y. Leclerc ◽  
G. Moreau

This study evaluated rate and timing of N fertilization effects on the N use efficiency characteristics of rain-fed Russet Burbank potato. Trials conducted in 1999–2001 included different rates of fertili zer N (0–160 kg N ha-1 in 1999 and 0–200 kg N ha-1 in 2000 and 2001) applied either at planting according to normal grower practice, or at hilling, the latest time that granular fertilizer can practically be applied. Whole-plant dry matter and N accumulation were determined at topkill. Soil inorganic N content was measured to 30-cm depth at planting and at tuber harvest. Soil N supply (plant N accumulation plus soil inorganic N content at harvest with no fertilizer N applied) varied from 77 to 146 kg N ha-1 depending on the year. Crop N supply (soil N supply plus fertilizer N applied) was a better predictor of plant N accumulation than fertilizer N rate, and was used to remove the confounding effect of variation in soil N supply when making among-year comparisons for N use efficiency characteristics. Nitrogen uptake efficiency (NUpE; plant N accumulation/crop N supply) decreased with increasing rates of N applied at hilling N rate in 1999, which was a dry year, but was not influenced by at-hilling N rate in 2000 and 2001, or by at-planting N rate in any year. Nitrogen use efficiency (NUE; dry matter accumulation/crop N supply) and N utilization efficiency (NUtE; dry matter accumulation/plant N accumulation) decreased curvilinearly with increasing crop N supply in each year. Similar relationships between NUE and crop N supply, and between NUtE and plant N accumulation, among the 3 yr of the study suggest that these relationships are largely independent of seasonal climatic variation, and are primarily genetically controlled. Timing of N fertilization had no effect on any N use efficiency parameter, with the exception of reduced NUpE associated with split N application in 1999. This suggests that under rain-fed potato production in Atlantic Canada, timing of N fertilization has no significant effect on N use efficiency of Russet Burbank potato in years of adequate soil moisture, but NUpE may be decreased by split application of N in dry years. Key words: Solanum tuberosum, soil inorganic N, apparent fertilizer N recovery


1998 ◽  
Vol 78 (4) ◽  
pp. 589-595 ◽  
Author(s):  
S. S. Malhi ◽  
K. Heier ◽  
M. Zhang ◽  
M. Nyborg

In central Alberta, surface-broadcast urea is usually less effective in increasing grass forage yield than ammonium nitrate (AN) due to volatilization loss. A 2-yr field experiment was conducted in 1994 and 1995 on meadow bromegrass (Bromus bibersteinii Roem and Shult 'Regar') at Eckville, Alberta to compare a number of synthetic con-trolled-release urea fertilizers with conventional urea and AN fertilizers for their effect on dry matter yield (DMY), protein yield (PY), N-use efficiency (NUE) and percent N recovery (NR). The N fertilizers were applied at 100 kg N ha−1 in early June of 1994 and mid-April of 1995. The meadow bromegrass was harvested three times during the May to September growing season. In both years there was a significant forage yield response to applied N. In 1994, the DMY, PY, NUE and NR were similar for urea and AN, and most of the treated urea products were inferior to urea alone. This was most likely due to delayed application of N fertilizer until just before the start of summer rains. In 1995, urea had lower DMY (by 874 kg ha−1), PY (by 177 kg ha−1), NUE (by 8.8 kg DM kg−1 N ha−1) and NR (by 27.3%) than AN. Some of the coated urea products (e.g., Sh. 19, Sh. G) gave significantly greater DMY, PY, NUE and NR than urea alone, though still less than AN. These results suggest that under conditions when surface-applied urea is inferior to AN, its effectiveness can be improved by using Sh. 19 and Sh. G controlled-release urea fertilizers on grassland. The controlled-release fertilizers may be more expensive and therefore, additional cost must be considered as compared with AN before using on a commercial basis. Key words: Ammonium nitrate, bromegrass, controlled-release N fertilizers, forage yield, N recovery, urea


Agriculture ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 541
Author(s):  
Gerhard Moitzi ◽  
Reinhard W. Neugschwandtner ◽  
Hans-Peter Kaul ◽  
Helmut Wagentristl

Improvements in nitrogen (N) use efficiency in crop production are important for addressing the triple challenges of food security, environmental degradation and climate change. The three fertilizers, calcium ammonium nitrate (CAN), urea (Urea) and stabilized urea (Ureastab), were applied at a rate of 160 kg N ha−1 with two or three splits to winter wheat (Triticum aestivum L.) in the Pannonian climate region of eastern Austria. On average, over all fertilization treatments, the grain yield (GY) increased by about a quarter and the grain N concentration (GNC) doubled compared to the control without fertilization. Consequently, the grain N yield (NYGRAIN) was increased with N fertilization by 154%. The GY increased due to a higher grain density with no differences between N fertilizers but with a tendency of a higher grain yield with three compared to two splits. Three splits also slightly increased the GNC and consequently the NYGRAIN of CAN and Ureastab in one year. The removal of N fertilizer with the NYGRAIN (N surplus) was higher than the amount of applied fertilizer. Fertilization decreased the N use efficiency (NUE), the N uptake efficiency (NUpE) and the N utilization efficiency (NUtE) but increased the soil mineral nitrate (NO3-N) at harvest and the apparent N loss (ANL). Three compared to two applications resulted in a higher NO3-N at harvest but also a lower N surplus due to partly higher NYGRAIN. Consequently, the ANL was lower with three compared to two splits. Also, the NUpE and the apparent N recovery efficiency (ANRE) were higher with three splits. The best N treatment regarding highest above-ground biomass yield with lowest N surplus, N balance and ANL was the three-split treatment (50 CAN, 50 CAN, 60 liquid urea ammonium nitrate). Three splits can, under semi-arid conditions, be beneficial when aiming high-quality wheat for bread-making and also for reducing the N loss. Whereas, two splits are recommended when aiming only at high GY, e.g., for ethanol-wheat production.


1989 ◽  
Vol 69 (4) ◽  
pp. 1179-1192 ◽  
Author(s):  
C. G. KOWALENKO ◽  
S. FREYMAN ◽  
D. L. BATES ◽  
N. E. HOLBEK

Seven field trials were conducted over 3 years (1984–1986) at two locations (Agassiz and Oyster River) in south coastal British Columbia to determine forage response to 100 kg N ha−1 applied at various time intervals in the spring according to the accumulation of average air temperatures above 0 °C from 1 Jan. (T-sum). A T-sum of 200 has been reported to be the optimum time for N application in western Europe and the United Kingdom. Both urea and ammonium nitrate were applied at the Oyster River location, while only ammonium nitrate was applied at Agassiz. First-cut forage dry matter production responded to the timing of N application in a variety of ways in the seven trials, with a decrease in growth as N was applied later in the season in most cases. In one trial, dry matter production was lowest at T-100 and T-150 compared to later times of application. Although there were variations among the trials, overall the highest yields occurred when N was applied at T-200 to T-300. Crop quality (%N or crude protein content), however, tended to increase as N was applied later in the season. Recovery of N in the plant and soil at harvest was relatively uniform for all times of N application and the distribution of extractable inorganic N in the soil profile suggested little N leaching. The dominant form of inorganic N found in the soil was ammonium. The cool soil temperatures and flush of plant and microbial activity probably contributed to the apparent lack of leaching and response of the grass to the N applied at various times early in the growing season. The timing of N application in the spring resulted in varying residual effects, whether N was applied or not after the first cut.Key words: N fertilization, yield, quality, timing, N recovery


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