Winter wheat yield and nitrous oxide emissions in response to cowpea-based green manure and nitrogen fertilization

AbstractThe aim of this study was to compare the effects of cowpea green manure and inorganic nitrogen (N) fertilizers on yields of winter wheat and soil emissions of nitrous oxide (N2O). The comparisons included cowpea grown solely as green manure where all biomass was terminated at maturity by tillage, summer fallow treatments with 90 kg N ha−1 as urea (90-N), and no fertilization (control) at planting of winter wheat. Fluxes of N2O were measured by closed chamber methods after soil incorporation of cowpea in autumn (October–November) and harvesting of winter wheat in summer (June–August). Growth and yields of winter wheat and N concentrations in grain and straw were also measured. Cowpea produced 9.5 Mg ha−1 shoot biomass with 253 kg N ha−1 at termination. Although soil moisture was favorable for denitrification after soil incorporation of cowpea biomass, low concentrations of soil mineral N restricted emissions of N2O from cowpea treatment. However, increased concentrations of soil mineral N and large rainfall-induced emissions were recorded from the cowpea treatment during summer. Growth of winter wheat, yield, and grain N concentrations were lowest in response to cowpea treatment and highest in 90-N treatment. In conclusion, late terminated cowpea may reduce yield of winter wheat and increase emissions of N2O outside of wheat growing seasons due to poor synchronization of N mineralization from cowpea biomass with N-demand of winter wheat.

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Dynamics of nitrogen capture without fertilizer: the baseline for fertilizing winter wheat in the UK

The Journal of Agricultural Science ◽

10.1017/s0021859600008479 ◽

2001 ◽

Vol 136 (1) ◽

pp. 15-33 ◽

Cited By ~ 24

Author(s):

R. SYLVESTER-BRADLEY ◽

D. T. STOKES ◽

R. K. SCOTT

Keyword(s):

Winter Wheat ◽

N Uptake ◽

Soil Horizon ◽

Soil N ◽

Soil Mineral N ◽

Fertilizer N ◽

Soil Mineral ◽

Mineral N ◽

Fertilizer Use ◽

The Uk

Experiments at three sites in 1993, six sites in 1994 and eight sites in 1995, mostly after oilseed rape, tested effects of previous fertilizer N (differing by 200 kg/ha for 1993 and 1994 and 300 kg/ha for 1995) and date of sowing (differing by about 2 months) on soil mineral N and N uptake by winter wheat cv. Mercia which received no fertilizer N. Soil mineral N to 90 cm plus crop N (‘soil N supply’; SNS) in February was 103 and 76 kg/ha after large and small amounts of previous fertilizer N respectively but was not affected by date of sowing. Previous fertilizer N seldom affected crop N in spring because sowing was too late for N capture during autumn, but it did affect soil mineral N, particularly in the 60–90 cm soil horizon, presumably due to over-winter leaching. Tillering generally occurred in spring, and was delayed but not diminished by later sowing. Previous fertilizer N increased shoot survival more than it increased shoot production. Final shoot number was affected by previous fertilizer N, but not by date of sowing. Overall, there were 29 surviving tillers/g SNS.N uptakes at fortnightly intervals from spring to harvest at two core sites were described well by linear rates. The difference between sowings in the fitted date with 10 kg/ha crop N was 1 month; these dates were not significantly affected by previous fertilizer. N uptake rates were increased by both previous fertilizer N and late sowing. Rates of N uptake related closely to soil mineral N in February such that ‘equivalent recovery’ was achieved in late May or early June. At one site there was evidence that most of the residue from previous fertilizer N had moved below 90 cm by February, but N uptake was nevertheless increased. Two further ‘satellite’ sites behaved similarly. Thus at 14 out of 17 sites, N uptake until harvest related directly and with approximate parity to soil mineral N in February (R2 = 0·79), a significant intercept being in keeping with an atmospheric contribution of 20–40 kg/ha N at all sites.It is concluded that, on retentive soils in the UK, SNS in early spring was a good indicator of N availability throughout growth of unfertilized wheat, because the N residues arising from previous fertilizer mineralized before analysis, yet remained largely within root range. The steady rates of soil mineral N recovery were taken as being dependent on progressively deeper root development. Thus, even if soil mineral N equated with a crop's N requirement, fresh fertilizer applications might be needed before ‘equivalent recovery’ of soil N, to encourage the earlier processes of tiller production and canopy expansion. The later process of grain filling was sustained by continued N uptake (mean 41 kg/ha) coming apparently from N leached to the subsoil (relating to previous fertilizer use) as well as from sources not related to previous fertilizer use; significant net mineralization was apparent in some subsoils.

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Dryland Winter Wheat Yield, Grain Protein, and Soil Nitrogen Responses to Fertilizer and Biosolids Applications

Applied and Environmental Soil Science ◽

10.1155/2011/925462 ◽

2011 ◽

Vol 2011 ◽

pp. 1-9 ◽

Cited By ~ 9

Author(s):

Richard T. Koenig ◽

Craig G. Cogger ◽

Andy I. Bary

Keyword(s):

Winter Wheat ◽

Production Systems ◽

Inorganic Nitrogen ◽

Wheat Yield ◽

Moisture Stress ◽

Grain Protein Content ◽

Grain Protein ◽

Inorganic N ◽

Winter Wheat Yield ◽

Eastern Washington

Applications of biosolids were compared to inorganic nitrogen (N) fertilizer for two years at three locations in eastern Washington State, USA, with diverse rainfall and soft white, hard red, and hard white winter wheat (Triticum aestivumL.) cultivars. High rates of inorganic N tended to reduce yields, while grain protein responses to N rate were positive and linear for all wheat market classes. Biosolids produced 0 to 1400 kg ha−1(0 to 47%) higher grain yields than inorganic N. Wheat may have responded positively to nutrients other than N in the biosolids or to a metered N supply that limited vegetative growth and the potential for moisture stress-induced reductions in grain yield in these dryland production systems. Grain protein content with biosolids was either equal to or below grain protein with inorganic N, likely due to dilution of grain N from the higher yields achieved with biosolids. Results indicate the potential to improve dryland winter wheat yields with biosolids compared to inorganic N alone, but perhaps not to increase grain protein concentration of hard wheat when biosolids are applied immediately before planting.

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Timing incorporation of different green manure crops to minimize the risk of nitrogen leaching

Agricultural and Food Science ◽

10.23986/afsci.5613 ◽

1998 ◽

Vol 7 (5-6) ◽

pp. 553-567 ◽

Cited By ~ 21

Author(s):

H. KÄNKÄNEN ◽

A. KANGAS ◽

T. MELA

Keyword(s):

Green Manure ◽

Trifolium Pratense ◽

Spring Barley ◽

Field Trials ◽

N Leaching ◽

Soil Mineral N ◽

Soil Mineral ◽

Mineral N ◽

Plant Materials ◽

N Content

Seven field trials at four research sites were carried out to study the effect of incorporation time of different plant materials on soil mineral N content during two successive seasons. Annual hairy vetch (Vicia villosa Roth), red clover (Trifolium pratense L.), westerwold ryegrass (Lolium multiflorum Lam. var. westerwoldicum) and straw residues of N-fertilized spring barley (Hordeum vulgare) were incorporated into the soil by ploughing in early September, late October and the following May, and by reduced tillage in May. Delaying incorporation of the green manure crop in autumn lessened the risk of N leaching. The higher the crop N and soil NO3-N content, the greater the risk of leaching. Incorporation in the following spring, which lessened the risk of N leaching as compared with early autumn ploughing, often had an adverse effect on the growth of the succeeding crop. After spring barley, the NO3-N content of the soil tended to be high, but the timing of incorporation did not have a marked effect on soil N. With exceptionally high soil mineral N content, N leaching was best inhibited by growing westerwold ryegrass in the first experimental year. ;

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Pea green manure management affects organic winter wheat yield and quality in semiarid Montana

Canadian Journal of Plant Science ◽

10.4141/cjps10109 ◽

2011 ◽

Vol 91 (3) ◽

pp. 497-508 ◽

Cited By ~ 29

Author(s):

P. R. Miller ◽

E. J. Lighthiser ◽

C. A. Jones ◽

J. A. Holmes ◽

T. L. Rick ◽

...

Keyword(s):

Winter Wheat ◽

Green Manure ◽

Wheat Yield ◽

Manure Management ◽

Yield And Quality ◽

Winter Wheat Yield

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Impact of legume 'break' crops on the residual amount and distribution of soil mineral nitrogen

Australian Journal of Agricultural Research ◽

10.1071/ar02149 ◽

2003 ◽

Vol 54 (8) ◽

pp. 763 ◽

Cited By ~ 12

Author(s):

J. Evans ◽

G. Scott ◽

D. Lemerle ◽

A. Kaiser ◽

B. Orchard ◽

...

Keyword(s):

Green Manure ◽

Grain Legumes ◽

Potential Contribution ◽

Soil N ◽

Soil Mineral N ◽

Soil Mineral ◽

Mineral N ◽

Total N ◽

Legume Crops ◽

Green Manure Crops

Important factors in the successful uptake of grain legumes by cereal growers have been their capacity to increase soil N and control cereal disease, as these have underpinned high yields in following wheat crops. However, alternative 1-year legume crops are required to introduce additional biodiversity and management flexibility for cereal growers. The effects on soil mineral N and potential contribution to soil total N of other legume enterprises were studied. These included vetch (Vicia bengalhensis) or clovers (mix of Trifolium alexandrinum, T.�versiculosum, T. resupinatum) managed for green manure; pea (Pisum sativum), vetch, or clovers managed for silage; and clovers managed for hay. These were compared with pea and lupin (Lupinus angustifolius) managed for grain production. Wheat was also included as a control. The legumes were grown in acidic Red Kandasol soil at Wagga Wagga in southern New South Wales, in 1996, 1997, and 1998. Mineral N was measured in the autumn or winter of seasons 1997 and 1998 respectively. Amounts of stubble residue N were measured in all seasons. The green manure crops, particularly vetch, produced more mineral N than both grain legumes. The forage conservation crops (silage or hay) produced similar amounts of mineral N to grain pea and more than grain lupin. For the grain and green manure legume crops, variation in amounts of mineral N was explained by the total N content of legume stubble residue, but for the forage conservation crops, more mineral N was measured than was predictable from stubble N. The amounts of mineral N at different soil depths differed between legume treatments and experiments (sites and years). Based only on above-ground plant N, the green manure crops contributed more to increasing total soil N than grain legumes; in turn, the grain legumes contributed more than the forage conservation crops. It was concluded that alternative annual legume enterprises to grain legumes may provide at least similar enrichment of soil mineral N early in the following season, and that all annual legume enterprises may accumulate nitrate deep in the soil profile in some seasons.

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Lucerne removal before a cropping phase

Australian Journal of Agricultural Research ◽

10.1071/ar99183 ◽

2000 ◽

Vol 51 (7) ◽

pp. 877 ◽

Cited By ~ 37

Author(s):

J. F. Angus ◽

R. R. Gault ◽

A. J. Good ◽

A. B. Hart ◽

T. D. Jones ◽

...

Keyword(s):

Soil Water ◽

Wheat Yield ◽

Growing Season ◽

Wheat Crop ◽

Grain Protein ◽

Residual Soil ◽

Soil Mineral N ◽

Soil Mineral ◽

Soil Mineral Nitrogen ◽

Mineral N

Growing dryland crops after lucerne is known to be risky because of the lack of residual soil water. We investigated ways of reducing this risk by removing portions of a lucerne pasture, using either herbicides or cultivation, at monthly intervals between November and April, before sowing a wheat crop in May, followed by a canola crop in the following year. The experimental site was on a red-brown earth in southern New South Wales. Lucerne removal was incomplete when the wheat was sown, so all lucerne plants were removed from half of each plot with a post-emergence herbicide, to allow comparisons of intercropped wheat–lucerne and wheat monoculture. Measurements were made on crop growth, yield, grain quality, soil water, and soil mineral nitrogen (N) before and after both crops. On average, each additional month between lucerne removal and wheat sowing led to a yield increase of 8% and a grain protein increase of 0.3 percentage units. The main reason for the increases was additional soil mineral N, associated with a longer period of mineralisation. The soil water content at the time of wheat sowing was greater with early lucerne removal but the growing season rainfall did not limit yields, and there was more residual soil water at the time of wheat maturity where lucerne had been removed late and yields were lower. Method of lucerne removal did not significantly affect wheat yield, grain protein, soil water, or soil mineral N. The portions of the plots containing lucerne plants that survived the initial removal attempt produced similar wheat yields to the portions where lucerne had been totally removed, but grain protein was lower. The following growing season was drier, but despite less residual soil water where lucerne had been removed earlier in the previous year, the average canola yield was 2.5% greater for each additional month of fallow. The increase again appeared to be due to more residual mineral N. The seed oil concentration also decreased in response to later lucerne removal but seed protein increased. Where lucerne plants had been retained in the previous wheat crop, canola yield was lower than where they had been totally removed, apparently because of less soil water at sowing. Over the 2 years of the experiment, the net supply of mineral N was 374 kg N/ha, equivalent to an annual net mineralisation of 2% of the total soil N. The initial mineralisation rate was slow, suggesting that the soil may be deficient in mineral N soon after lucerne removal.

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