FATE OF N APPLIED AS GREEN MANURE OR AMMONIUM FERTILIZER TO SOIL SUBSEQUENTLY CROPPED WITH SPRING WHEAT AT THREE SITES IN WESTERN CANADA

1990 ◽  
Vol 70 (3) ◽  
pp. 313-323 ◽  
Author(s):  
H. H. JANZEN ◽  
J. B. BOLE ◽  
V. O. BIEDERBECK ◽  
A. E. SLINKARD
Keyword(s):  
Organic Matter ◽  
Ammonium Sulfate ◽  
Spring Wheat ◽  
Green Manure ◽  
Field Experiments ◽  
Soil Layer ◽  
Organic N ◽  
Wheat Crop ◽  
Western Canada ◽  
Annual Legumes

There is growing interest in the use of annual legumes as green manure crops to replace conventional summerfallow in the spring wheat production systems of western Canada. A series of field experiments was established at three sites in western Canada (Lethbridge, Swift Current, and Saskatoon) in each of two seasons to quantify the N contribution of green manure to subsequent crops and organic matter reserves. 15N-labelled plant material from two annual legume species [Tangier flatpea (Lathyrus tingitanus 'Tinga') and lentil (Lens culinaris 'Indianhead')], as well as 15N-labelled ammonium sulfate, was applied to field microplots in midsummer. The following spring, an additional ammonium sulfate treatment was established and all plots were seeded to spring wheat (Triticum aestivum 'Leader' or 'Katepwa'). On average, the wheat crop recovered 14% of the green manure N compared with 36% of the fertilizer N. Conversely, the relative contribution of the green manure to the organic N pool in the surface soil layer was approximately twice that of inorganic fertilizer. This residual organic N was relatively recalcitrant to further mineralization, as was evident from minimal uptake of applied N in the second year after application. These results suggest that annual legumes can be a significant source of N to subsequent crops in the rotation, provided that N yields are sufficient. The primary advantage of green manure production, however, may be the long-term replenishment of stable organic N reserves in the soil. Key words: N mineralization, organic matter, 15N, annual legumes, green manure, lentil, pea

scholarly journals Residual Effect of Poultry Manure and Mineral N Application on Maize Production under Wheat-Maize Cropping System

2017 ◽  
Vol 5 (9) ◽  
pp. 1061
Author(s):  
Syed Azam Shah ◽  
Wisal Mohammad ◽  
Haroon Haroon ◽  
Adnan Anwar Khan
Keyword(s):  
Grain Yield ◽  
Field Experiments ◽  
Poultry Manure ◽  
Residual Effect ◽  
Grain Weight ◽  
Organic N ◽  
Wheat Crop ◽  
Silty Clay ◽  
Mineral N ◽  
1000 Grain Weight

The study was designed to asses the residual effect of organic N (Poultry Manure) and mineral N on maize crop in field experiments carried out on silty clay loam soil at NIFA, Tarnab, Peshawar, Khyber Pakhtunkhwa (KP) Pakistan during 2014-15. Combined dose of N from both sources were 120 kg ha-1 applied to wheat crop alone and in different combination making six treatments. Maize variety (Azam) was sown in Randomized complete block (RCB) design with four replications. Agronomic data, grains ear-1, 1000 grain weight, biomass grain yield data, N-uptake in maize grain and straw were recorded. Results showed that maximum grain ear−1, 1000 grain weight, biomass and grain yield was obtained from treatment where 25% N applied from poultry manure + 75% from mineral N source applied to previous wheat crop. Agronomic efficiency and nitrogen use efficiency were also found maximum in treatment where 75% poultry manure + 25% mineral N was applied. It was concluded from the study that residual effect of organic manure with mineral N in different ratios enhances crop productivity and soil fertility.

Seed-Mediated Gene Flow in Wheat: Seed Bank Longevity in Western Canada

Weed Science ◽  
2009 ◽  
Vol 57 (1) ◽  
pp. 124-132 ◽  
Author(s):  
Ryan L. Nielson ◽  
Marc A. McPherson ◽  
John T. O'Donovan ◽  
K. Neil Harker ◽  
Rong-Cai Yang ◽  
...  
Keyword(s):  
Regression Analysis ◽  
Gene Flow ◽  
Seed Size ◽  
Spring Wheat ◽  
Seed Bank ◽  
Seed Viability ◽  
Wheat Crop ◽  
Western Canada ◽  
Viable Seed ◽  
Wheat Seed

Development of genetically modified (GM) wheat has raised concerns about the movement and persistence of transgenes in agroecosystems and the ability of growers to segregate GM from conventional wheat. Wheat as a crop has been studied extensively but the population biology of volunteer wheat is not well characterized. Artificial seed bank studies were conducted in western Canada to provide baseline data on volunteer wheat seed persistence. Seed from two cultivars of Canadian western red spring wheat, ‘AC Splendor’ and ‘AC Superb’, were buried in mesh bags at three depths (0, 2, and 15 cm) in two different environments in the fall of 2003 and 2004. In addition, in 2004, ‘AC Superb’ seed were separated into small and large seed lots and buried with a medium seed lot to examine the influence of seed size on seed bank persistence. Seeds were withdrawn at intervals to assess seed germination and viability and regression analysis conducted on the viable seed at each sample period, after burial. Seed viability was variable within years and sites, and declined exponentially over time. In the spring, approximately 6 mo after initiation, viable seed ranged from 1 to 43%. With the exception of a single site and year, seeds on the soil surface persisted significantly longer than buried seeds and increasing burial depth accelerated loss of viability. The maximum viability of wheat seeds at 0, 2, and 15 cm depth in the spring following planting was 43, 7, and 2%, respectively. The extinction of viability for 99% (EX99) of the seed was estimated from regression analysis. The EX99values of seeds buried at 0, 2, and 15 cm ranged from 493 to 1,114, 319 to 654, and 175 to 352 d after planting (DAP), respectively, with the exception of one site in 2003 where burial depths were not different and all had an EX99value of 456 DAP. Seed size and cultivar did not significantly affect persistence, with the exception of one site in 2003 where the difference in EX99values was 20 DAP. The rapid loss of seed viability limits temporal gene flow via volunteers in years following a wheat crop. Results provide data on spring wheat biology to aid in Canadian environmental biosafety assessments of GM wheat and will be incorporated into a mechanistic model to predict wheat gene flow on the Canadian prairies.

The impact of diversification of a rice–wheat cropping system on crop productivity and soil fertility

2002 ◽  
Vol 139 (4) ◽  
pp. 405-412 ◽  
Author(s):  
V. K. SINGH ◽  
B. B. SHARMA ◽  
B. S. DWIVEDI
Keyword(s):  
Soil Fertility ◽  
Green Manure ◽  
Protein Production ◽  
Field Experiments ◽  
Block Design ◽  
Crop Productivity ◽  
Research Centre ◽  
Wheat Crop ◽  
Cropping Intensity ◽  
The Impact

Field experiments were conducted at the Crop Research Centre of Govind Ballabh Pant University of Agriculture and Technology, Pantnagar during 1996/97 and 1997/98. Each experiment comprised 10 crop sequences: (a) wheat–rice, (b) chickpea–rice, (c) lentil–rice, (d) pea–rice, (e) wheat–mungbean green manure–rice, (f) wheat–Sesbania green manure–rice, (g) wheat–fodder–rice, (h) chickpea–fodder–rice, (i) lentil–fodder–rice and (j) pea–fodder–rice, in a randomized block design with four replications. The crop sequences were compared in terms of economic rice equivalent yield (REY), protein production, apparent nutrient balances and effect on soil fertility status. Amongst crop sequences involving two crops each year (200% cropping intensity), chickpea–rice gave highest REY and protein production. Of the sequences involving three crops each year (300% cropping intensity), chickpea–fodder–rice and wheat–fodder–rice were superior to others. The P balances were positive for all sequences, whereas K balances were generally negative except for sequences involving green manure legumes. Green manuring with Sesbania or mungbean helped restore soil fertility, indicating the advantage of green manure for higher productivity and sustainability of rice–wheat system. Chickpea–rice and chickpea–fodder–rice appeared promising alternatives to rice–wheat crop sequence.

The effect of stubble management on the availability of 15N-labelled residual fertilizer nitrogen and crop stubble nitrogen in an irrigated black earth

1986 ◽  
Vol 26 (1) ◽  
pp. 99 ◽  
Author(s):  
PJ White ◽  
I Vallis ◽  
PG Saffigna
Keyword(s):  
Ammonium Sulfate ◽  
Field Experiments ◽  
Crop Yields ◽  
N Uptake ◽  
Fertilizer Application ◽  
Wheat Crop ◽  
Total N ◽  
Stubble Retention ◽  
Residual Fertilizer N ◽  
Subtropical Environment

Field experiments on an irrigated alkaline black earth soil of the Darling Downs, south-east Queensland, examined transformations of nitrogen (N) and its subsequent availability for the growth of wheat after stubble had been removed, mulched or incorporated. Two crop sequences were used: sorghum-3- month fallow-wheat (S-W); and wheat-7-month fallow-wheat (W-W). The crops were grown in microplots enclosed by steel cylinders (75 cm diam. and 35 cm deep) to a depth of 30 cm. For the initial crop, some plots were fertilized with l5N-labelled ammonium sulfate and others with unlabelled ammonium sulfate (50 kg N/ha). After harvest of the initial crop, labelled stubble was added to unlabelled soil, either as a mulch or incorporated, and unlabelled stubble was similarly added to soil labelled with residual 15N from the fertilizer application. Uptake of 15N by a test wheat crop and distribution of 15N in the soil-plant system were then determined. In the test crop fertilized with unlabelled urea (50 kg N/ha), incorporation of stubble depressed plant growth and N uptake by 35% in the S-W sequence but had no effect in the W-W sequence. Residual fertilizer 15N in the soil was more available to the test crop than was 15N in retained stubble (6 v. 2% and 12 v. 6% for the S-W and W-W sequences respectively). However, the test crop obtained only 0.9-1.2% of its total N uptake from residual fertilizer N and 0.4-2.9% from the stubble of the initial crop. The effects of stubble management on the availability of N from these two sources were small. If suitable rates of N fertilizer are applied, it is unlikely that crop yields will be adversely affected by stubble retention in this subtropical environment.

scholarly journals AGROCHEMICAL EVALUATION OF THE EFFICACY OF BIOPREPARATIONS IN A HIGHLY CROP ROTATION

2020 ◽  
Vol 31 ◽  
pp. 44-50
Author(s):  
О. М. Berdnikov ◽  
V. V. Volkohon ◽  
L. V. Potapenko ◽  
S. F. Kozar
Keyword(s):  
Organic Matter ◽  
Winter Wheat ◽  
Crop Rotation ◽  
Green Manure ◽  
Azospirillum Brasilense ◽  
Soil Layer ◽  
Biogenic Element ◽  
Mineral Fertilization ◽  
Fertilization System ◽  
By Products

Objective. Determine the parameters of uptake of organic matter and biogenic elements withby-products of crops under the use of mineral and green-manure-mineral fertilization systems andmicrobial preparations. Methods. Field experiment, agrochemical, balance, statistical. Results.Under the conditions of short crop rotation “winter wheat – intermediate green manure – corn forgrain – soybean – winter wheat”, the influence of microbial preparations Biogran (on the basis ofnitrogen-fixing bacterium Azospirillum brasilense 410 and physiologically active substances) forcorn and Nitro-Legu (on the basis of complex of diazotrophs Bradyrhizobium japonicum, Azospirillum brasilense and polysaccharide) for soybeans on crop yields, uptake of by-products in the soil,balance of nitrogen, phosphorus and potassium depending on fertilization systems. Under exposureto biopreparations, uptake of corn by-product in the soil increased by 1.41–2.12 t/ha, soybeans —by 0.51–0.71 t/ha of dry matter, depending on the agrarian backgrounds, which, taking into account the humification factors, can provide soil replenishment with humus at the level of 0.31 to0.47 t/ha and 0.12–0.17 t/ha, respectively. Nitrogen and phosphorus balances, as well as their intensity under the mineral fertilization system were positive. Green-manure-mineral fertilization system and pre-sowing bacterization of seeds helped to improve the parameters compared to the mineral fertilization system. Potassium balance was slightly deficient (–16.2 to 20.4 kg/ha at a balanceintensity of 78–80 %) under exposure to the mineral fertilization system and positive under exposure to green-manure-mineral system. Microbial preparations helped to improve parameters. Additional uptake of the biogenic element compounds in the soil provided an increase in the yield ofwinter wheat. According to the results of the evaluation of the balance of the key nutrients, a satisfactory ecological balance was created in the short crop rotation under exposure to green-manuremineral fertilization system and pre-sowing bacterization of corn and soybean seeds. Conclusion. Upon evaluation of the efficacy of microbial preparations in crop cultivation technologies, theparameters of uptake of organic matter and biogenic element compounds with by-products in the arable soil layer should be taken into account along with their direct effect on yield formation andproduct quality.

EFFECTS OF CROP ROTATIONS AND FERTILIZATION ON YIELDS AND QUALITY OF SPRING WHEAT GROWN ON A BLACK CHERNOZEM IN NORTH-CENTRAL SASKATCHEWAN

1990 ◽  
Vol 70 (2) ◽  
pp. 383-397 ◽  
Author(s):  
R. P. ZENTNER ◽  
C. A. CAMPBELL ◽  
K. E. BOWREN ◽  
W. EDWARDS
Keyword(s):  
Spring Wheat ◽  
Green Manure ◽  
Triticum Aestivum L ◽  
Crop Rotations ◽  
Organic N ◽  
Silty Clay ◽  
Total N ◽  
Crop Sequence ◽  
Legume Green Manure

Effects of rotation length, crop sequence, and fertilization on yields and quality of spring wheat (Triticum aestivum L.) were examined for eight crop rotations over a 27-yr period (1960-1986) on an Orthic Black Chernozem at Melfort, Saskatchewan. The silty clay loam soil had an initial organic N content of about 0.55% (0-to 15-cm depth). During 1960-1971, fertilized plots received N and P based on general recommendations for the region; thereafter, fertilizer was applied based on soil tests. Yields of wheat grown on fertilized fallow were similar for fallow-wheat, fallow-wheat-wheat (F-W-W), and a 6-yr fallow-wheat-legume hay rotation (avg. 2519 kg ha−1 in 1960-1971 and 3036 kg ha−1 in the wetter 1972-1986 period). In contrast, yields of wheat grown on fertilized stubble in a F-W-W rotation (avg. 2113 kg ha−1 in 1960-1971 and 2775 kg ha−1 in 1972-1986) averaged 34% higher than yields of continuous monoculture wheat due to fewer observed weed and disease problems. Fertilized stubble wheat yields in F-W-W averaged 88% of comparable fallow wheat yields, while continuous wheat averaged only 66%. Fertilizer increased fallow wheat yields by 14-18%. Stubble wheat yields were increased 11–16% for 3-yr rotations and 26% for continuous wheat during 1960-1971 when relatively low rates of N fertilizer were applied, and 22–31% and 49% for these same rotations, respectively, during 1972-1986 when moisture was more favorable and soil test criteria were used. Inclusion of grass-legume hay or legume green manure crops in the rotations provided no yield benefit for subsequent wheat crops in this fertile soil. The yields of wheat from fertilized rotations increased significantly with years of study reflecting the higher fertilizer rates used in later years and use of improved production technologies. Wheat yields of unfertilized treatments generally increased or showed no trend with time, thus providing no evidence of declining soil fertility. Crude protein concentration and total N yield of the grain were significantly increased by fertilization and inclusion of a grass-legume hay crop in the rotation. Total grain P yield of wheat was also influenced by fertilizer and by rotation, while volume weight of grain was unaffected by treatment.Key words: N and P fertilizer; grass-legume hay; legume green manure; crop sequence; protein

SOIL ORGANIC MATTER CHARACTERISTICS AFTER LONG-TERM CROPPING TO VARIOUS SPRING WHEAT ROTATIONS

1987 ◽  
Vol 67 (4) ◽  
pp. 845-856 ◽  
Author(s):  
H. H. JANZEN
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Soil Fertility ◽  
Crop Rotation ◽  
Spring Wheat ◽  
N Mineralization ◽  
Soil Layer ◽  
Organic C ◽  
C And N

Soil from a long-term crop rotation study conducted at Lethbridge, Alberta was analyzed to determine the influence of various spring wheat rotations with and without perennial forages on total and mineralizable soil organic matter contents. Crop rotations considered included: continuous wheat (W), fallow-wheat (FW), fallow-wheat-wheat (FWW), and fallow-wheat-wheat-forage-forage-forage (FWWAAA) in which the forage was a mixture of alfalfa and crested wheat grass. The organic C and N contents of soil after 33 yr of cropping were highest in treatments W and FWWAAA, and decreased with increasing frequency of fallow in the rotation. The inclusion of the perennial forage in the rotation did not increase organic C and N levels above those observed in the continuous wheat treatment (W). Differences in levels of mineralizable organic matter among treatments, as measured in laboratory incubations, were much greater than differences in total organic matter content among treatments. In the surface soil layer (0–15 cm), N mineralization was significantly higher in treatment W than in treatments FWW and FWWAAA, and was more than twice that observed in treatment FW. In the subsurface soil layer (15–30 cm), N mineralization was greatest in treatment FWWAAA when sampled just after the plowdown of forage. Effects of crop rotation on C mineralization were similar to those observed for N. Levels of mineralized organic matter were closely related to levels of "light fraction" material (specific gravity < 1.59 g cm−3), which is believed to consist primarily of incompletely decomposed organic matter of plant origin. Differences in amounts of mineralizable organic matter among treatments were attributed to varying frequencies and patterns of crop residue additions. The pronounced effects of crop rotation on the distribution of organic matter among labile and humified organic matter will have a strong impact on soil fertility and may need to be taken into consideration in the development of fertilizer recommendations. It was concluded that inclusion of perennial forages in spring wheat rotations for the purpose of enhancing soil fertility and organic matter levels was not justified under semiarid conditions. Key words: Carbon, nitrogen, mineralization

Fate of urea nitrogen in sheep urine applied to soil at different times of the year in the pasture - wheat rotation in south Western Australia

1998 ◽  
Vol 49 (3) ◽  
pp. 495 ◽  
Author(s):  
R. B. Thompson ◽  
I. R. P. Fillery
Keyword(s):  
Field Experiments ◽  
Summer Rainfall ◽  
Bare Soil ◽  
Organic N ◽  
Wheat Crop ◽  
Winter Rainfall ◽  
Grazed Pasture ◽  
15N Urea ◽  
C 50 ◽  
Sheep Urine

Sheep urine labelled with 15N-urea was applied toconfined micro-plots at different times of the year to follow the fate of ureaN in urine in the grazed pasture-wheat rotation in south Western Australia.Three field experiments were conducted on the same site on a loamy sand.Applications were made either to pasture residues (Expts 1 and 2) which weresubsequently sown to wheat, orto growing pasture in winter-spring, (Expt 3).In Expt 1, urine was applied in November 1990 (9·8 gN/m2) and April 1991 (46·1 gN/m2). From both applications, losses of15N attributed to NH3volatilisation were c. 50% within 2 weeks of application. Another10% loss was attributed toNO-3 leaching during the followinggrowing season and 15% was recovered by the wheat crop. In Expt 2,urine was applied in October 1991 (4·6 gN/m2), January 1992 (15·6 gN/m2), and March 1992 (13·6 gN/m2). Attributed NH3 losseswithin 2 weeks, in terms of 15N-urea applied, were40% (October and January urine) and 30% (March urine) andNO-3 leaching losses were estimated to be 20% forthe 3 applications. Recoveries in wheat (November 1992) were 4, 7, and12% of 15N applied in the October, January, andMarch urine applications. In Expt 3, urine was applied in August 1992(12·3 g N/m2) and September 1992 (25·9g N/m2). Attributed NH3 losseswere 10% of applied 15N for the August and30% for the September application. Plant uptake of15N was rapid and by mid October was 42% from theAugust application and 47% from the September application. Recovery of15N in soil organic N was generally 17-25% whenurine was applied to pasture residues and bare soil,and 21-37% whenurine was applied to growing pasture. It is suggested thatNH3 volatilisation was the predominant N loss mechanism.The amount of NO-3 leached wasprimarily influenced by summer rainfall, the length of time urine-N was insoil before the onset of winter rainfall, and the distributionof winterrainfall. Little of the 15N-labelled urine was eitherrecovered by, or available for, subsequent wheat crops, suggesting thatcalculations for estimating the N supply from pastures to cereal cropsmustdiscount most N returned in urine by grazing animals.

Control of volunteer flax in wheat

1999 ◽  
Vol 79 (3) ◽  
pp. 463-468 ◽  
Author(s):  
David A. Wall ◽  
Marjorie A. H. Smith
Keyword(s):  
Spring Wheat ◽  
Field Experiments ◽  
Yield Loss ◽  
Wheat Yield ◽  
Good Control ◽  
Field Trials ◽  
Wheat Crop ◽  
Poor Control ◽  
Control Volunteer ◽  
Biomass Reduction

Volunteer flax (Linum usitatissimum) can interfere with harvesting operations in cereals, especially at high flax densities. Field experiments were conducted in 1996 and 1997 at Morden and Brandon, Manitoba, Canada, to evaluate tribenuron and thifensulfuron plus tribenuron (2:1) alone and in mixtures with 2,4-D, quinclorac, flamprop-methyl and fluroxypyr for their ability to control volunteer flax in spring wheat. Volunteer flax cvs. NorLin and CDCTriffid, a transgenic, sulfonylurea-tolerant cultivar, were cross-seeded to plots of spring wheat cv. AC Domain. Herbicides were applied at rates recommended for their use in spring wheat, when wheat was at the three- to four-leaf stage and flax was 5–8 cm tall. When left uncontrolled, volunteer flax reduced wheat yields by up to 27%. Tribenuron and thifensulfuron plus tribenuron (2:1) provided poor control of NorLin flax and almost no control of Triffid flax. Flax density was not reduced, but biomass was reduced to some extent, more for NorLin than for Triffid. The addition of 2,4-D to the tank-mixes of the sulfonylurea herbicides had some effect on flax biomass reduction but results were not consistent. Wheat yields were reduced in three of the five field trials. The other herbicides controlled NorLin and Triffid flax equally well. Quinclorac at 100 and 200 g a.i. ha−1 provided consistently good flax control, generally without yield loss to the wheat crop. Fluroxypyr plus 2,4-D and fluroxypyr plus clopyralid plus MCPA were as effective as quinclorac, but were tested only in 1 yr. Flamprop-methyl reduced flax biomass and provided good control in 1997, but control was poor in 1996 and resulted in wheat yield losses. Recently, quinclorac has been registered for use against volunteer flax in spring wheat. Key words: Volunteer flax, sulfonylurea resistant flax, spring wheat, control, yield loss

scholarly journals Phosphorus Biofertilizers from Ash and Bones—Agronomic Evaluation of Functional Properties

2016 ◽  
Vol 8 (6) ◽  
pp. 58 ◽  
Author(s):  
Magdalena Jastrzebska ◽  
Marta K. Kostrzewska ◽  
Kinga Treder ◽  
Wieslaw P. Jastrzebski ◽  
Przemyslaw Makowski
Keyword(s):  
Functional Properties ◽  
Spring Wheat ◽  
Field Experiments ◽  
Crop Residues ◽  
Wheat Yield ◽  
Control Treatment ◽  
Wheat Crop ◽  
Agricultural Practice ◽  
Good Agricultural Practice ◽  
Weed Infestation

<p>Renewable raw materials could be a valuable source of phosphorus for plants. The bioavailability of this element can be enhanced by phosphorus-solubilizing bacteria. Suspension biofertilizers have been produced from sewage sludge ash and animal bones and enriched with the bacteria <em>Bacillus megaterium</em>. The functional properties of these preparations were compared in field experiments (northeast Poland, 2014, four replications) on spring wheat (<em>Triticum aestivum</em> ssp. <em>vulgare</em> Mac Key) to conventional fertilizers (superphosphate, phosphorite), ash-water solution (without microorganisms) and a control treatment without P fertilization. The soil type and cultivation regime were adjusted to the requirements of spring wheat in line with good agricultural practice. The effects of biofertilizers on the following were investigated: wheat yield, ear density, number of grains in the ear, the weight of 1000 grains, harvest index, weed infestation, the weight and structure of crop residues, and the pH of soil. Phosphorus biofertilizers from ash and bones equalled commercial fertilizers in terms of their crop-enhancing efficiency. Biofertilizer from ash, and ash diluted with water reduced weed infestation of the growing crop. Biofertilizer from bones resulted in a greater weight of wheat crop residues. Biofertilizers did not change the pH of soil. It is expected that the production of biofertilizers containing recycled phosphorus will be an alternative to its non-renewable resources and will also contribute to effective waste management.</p>

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