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1.
T. B. Whitaker M. E. Whitten R. J. Monroe 《Journal of the American Oil Chemists' Society》1976,53(7):502-505
The sampling, subsampling, and analytical variance associated with testing cottonseed for aflatoxin were estimated by use
of 4.54 kg samples, 100 g subsamples, and the Velasco method of analysis. Regression analysis indicated that each of the above
variance components is a function of the concentration of aflatoxin in the populations tested. Functional relationships are
presented to determine the sampling, subsampling, and analytical variance for any size sample, subsample, and number of analyses.
Paper 4821 of the Journal Series of the North Carolina Agricultural Experiment Station, Raleigh, NC 27607. 相似文献
2.
Variability of aflatoxin test results 总被引:1,自引:0,他引:1
T. B. Whitaker J. W. Dickens R. J. Monroe 《Journal of the American Oil Chemists' Society》1974,51(5):214-218
Using 12 lb samples, 280 g subsamples, the Waltking method of analysis, and densitometric procedures, the sampling, subsampling, and analytical variances associated with aflatoxin test procedures were estimated. Regression analysis indicated that each of the above variance components is a function of the concentration of aflatoxin in the population being tested. Results, for the test procedures given above, showed that sampling constitutes the greatest single source of error, followed by subsampling and analysis. Functional relationships are presented to determine the sampling, subsampling, and analytical variance for any size sample, subsample, and number of analyses. 相似文献
3.
Nine samples of fuzzy cottonseed potentially high in aflatoxin were separated into hulls, fines and meats. Assays for aflatoxin on triplicate 50-g portions from fines (small, dry particles of kernels) and meats from each of the nine samples indicated a marked concentration of toxin in the fines. On average, there was a 17-fold difference between the aflatoxin content of the fines and that of the meats; the average toxin level in fines was 4024 μg/kg and that in the meat samples was 232 μg/kg. These results indicate a potential for marked reduction in aflatoxin content of processed cottonseed meal by physical removal of fines from meats after dehulling and before processing of meats into oil and meal. 相似文献
4.
Timothy E. Lawlor Steve R. Haworth Errol Zeiger Douglas L. Park Louise S. Lee 《Journal of the American Oil Chemists' Society》1985,62(7):1136-1138
In a joint research effort, the Food and Drug Administration, the National Toxicology Program and the US Department of Agriculture
studied the mutagenic potential of aflatoxin reaction products following ammoniation of contaminated cottonseed meal under
conditions approximating those approved for commercial ammoniation of nonaflatoxin-contaminated meal. Uniformly ring-labeled14C-aflatoxin B1 was added to cottonseed meal that contained ca. 4000 μg naturally incurred aflatoxin B1/kg. Distribution of the radiolabeled compound was used to trace the modification of aflatoxin B1 after treatment with ammonia. The radioactivity-to-weight ratio of the fractions isolated by solvent extractions and chemical
and enzymic treatments was used to measure the relative concentration of an aflatoxin decontamination product. All extract
fractions having a radioactivity-to-weight ratio ≥1 were tested for mutagenic activity using theSalmonella/microsome mutagenicity test (Ames test). Purified aflatoxin B1 was mutagenic at a concentration of ca. 0.005 μg/plate. The methylene chloride extract of the ammoniated meal after Pronase
digestion exhibited a similar response when 180 μg of this fraction was applied to each plate. This fraction represented 0.16%
of the original added radioactivity. The other fractions produced no detectable mutagenic response at the concentrations tested
(10–1000 μg/plate) onSalmonella tester strain TA100. Ammonia treatment of aflatoxin-contaminated cottonseed meal significantly decreased aflatoxin levels,
and the aflatoxin decontamination products formed by the treatment had little or no mutagenic potential. 相似文献
5.
A major portion of aflatoxin contamination of peanuts probably occurs when decayed or discolored peanuts are incompletely
removed by sorting. Quality control measures have been instituted in the United States to insure that unavoidable aflatoxins
in consumer peanuts and peanut products do not exceed 20 μg/kg. However, low level aflatoxin contamination, from trace amounts
to about 50 μg/kg in sound mature unblemished peanuts, can occur before peanuts are dug. This low level contamination is not
related to high levels of Aspergillus flavus infection or to current production practices. Low level aflatoxin contamination
of peanuts may be endemic, and current sorting procedures may not be effective in removing unblemished contaminated peanuts. 相似文献
6.
Timothy H. Sanders Jack L. McMeans J. I. Davidson 《Journal of the American Oil Chemists' Society》1984,61(12):1839-1841
The degree of aflatoxin contamination in peanut hulls was determined by analyzing inoculated hand-shelled hulls and hulls
from peanuts known to contain aflatoxin. Hulls adjusted to 20% moisture, inoculated withAspergillus flavus, and incubated 7 days at 25 C supported growth ofA. flavus but not aflatoxin production. Peanuts from 20 selected Segregation III (visibleA. flavus) lots contained 13–353 ppb of aflatoxin. The machine-shelled hulls from these lots were analyzed and 3 lots contained no
detectable aflatoxin, 13 lots contained 4–88 ppb and 4 lots contained >116 ppb. Aflatoxin concentrations of 53–87 ppb were
detected in hulls when peanuts containing relatively high levels of aflatoxin (up to 26.8 ppm in damaged kernels) were carefully
machine-shelled. Hulls from the same samples obtained by hand-shelling contained no detectable aflatoxin. When machine-shelled
hulls were screened through successively smaller screens, the aflatoxin concentration of the smallest fraction (<3.18 mm)
was always highest and indicated that small peanut kernels and peanut parts in the hulls actually contained the aflatoxin.
Separating hulls over a 4.76 mm round-hole screen appeared to provide a means of removal of most aflatoxin in peanut hulls.
No aflatoxin was found in hulls from uncontaminated peanuts. 相似文献
7.
John D. Mckinney George C. Cavanagh J. T. Bell A. S. Hoversland D. M. Nelson J. Pearson R. J. Selkirk 《Journal of the American Oil Chemists' Society》1973,50(3):79-84
A multifaceted cooperative research program involving industry, government and universities was initiated to determine the
effects of feeding lactating dairy cows rations containing various levels of cotton-seed and cottonseed meal that had been
naturally contaminated with aflatoxins. Evidence is presented that ammoniation of aflatoxin-contaminated cottonseed and cottonseed
meal eliminates the aflatoxins, producing a product safe for feeding to ruminants. The aflatoxin M1 content of milk samples of individual cows receiving rations containing (a) prime cottonseed meal, (b) aflatoxin contaminated
meal, and (c) aflatoxin contaminated meal that had ammoniation treatment is reported. Data comparing results with (d) prime
cottonseed, (e) aflatoxin contaminated seed, and (f) aflatoxin-contaminated seed that had ammoniation treatment are also reported.
None of the milk samples from cows fed ammoniated rations contained any detectable M1 by the modified Jacobson et al. methodology used. The sensitibity of the method in this laboratory is 0.1 μg M1/liter of milk. Under the conditions of this study, aflatoxin M1 levels are related to the levels of aflatoxin B1 consumed in the diet of the cows. Conversion ratios are reported. Aflatoxin M1 levels in the milk, relative to the time of the cows’ initial ingestion of aflatoxin B1, the persistence of M1 in the milk after discontinuing ingestion of B1, and disappearance of M1 under the conditions of the analytical methodology used relative to storage time and temperatures, are reported for liquid
milk and for frozen milk. Milk containing the highest level of aflatoxin M1 was treated with rennet. An 80:20 partion of aflatoxin M1 was observed between curd and whey, respectively. 相似文献
8.
Douglas L. Park Louise Lee S. A. Koltun 《Journal of the American Oil Chemists' Society》1984,61(6):1071-1074
The fate of aflatoxin during ammoniation of contaminated cottonseed meal was studied under conditions approximating those
approved for commercial ammoniation of nonaflatoxin-contaminated meal. Uniformly ring-labeled14C-aflatoxin B1 was added to 27.7 kg meal (14% moisture) that contained ca. 4000 μg naturally incurred aflatoxin B1/kg. Distribution of the radiolabeled compound was used to trace the modification of aflatoxin B1 after treatment with 4% ammonia at 40 psi, 100 C for 30 min. This treatment reduced the chemically detected aflatoxin B1 to less than 4 μg/kg. In control nonammoniated meals, 90% of the radiolabeled material was accounted for in the methylene
chloride extract. Duplicate 2-kg samples of the ammoniated meal were fractionated and the distribution of radioactivity was
determined. Ca. 86% of the radioactivity was detected in the meal after initial air-drying. Ca. 25% of the added radioactivity
was extracted from the air-dried meal with methylene chloride and another ca. 5% was extracted from this residue with methanol.
Weak acid released 3% of the added radioactivity from the residue after methanol extraction, bicarbonate released 1% and Pronase
digestion, including methylene chloride extraction of the residue, accounted for nearly 19% of the total added radioactivity.
Only 37% of the added radioactivity remained in the meal matrix following solvent extractions and chemical and enzymic treatments. 相似文献
9.
Friedrich Schne Ulrich Kirchheim Frank Tischendorf Berd Rudolph 《European Journal of Lipid Science and Technology》1997,99(1):15-18
Evaluation of linseed feedstuffs (ground linseed, solvent extracted linseed meal) with growing pigs – feed value, thiocyanate and thyroid hormone status. Ground linseed (Linum usitatissimum) was tested with 9 fattening pigs in a digestibility experiment. Barley (control diet) was partially replaced either by 25% or 50% ground linseed. In three periods three animals of each of the three groups (latin square) received a diet without or with 25% or 50% ground linseed. In two feeding experiments a total of 120 weaned piglets received diets either without and with 10% ground linseed or without and with 10% solvent extracted linseed meal (Exp. 2). A low apparent organic matter digestibility of 66% of ground linseed was primarily caused by 40% apparent digestibility of crude carbohydrates (crude fibre + N-free extract). In linseed groups the intake of lignin and its faecal excretion was high. It seems that the undigestible lignin is one, however not the sole reason of reduced digestibility. A relatively high metabolizable energy of 18MJ/kg linseed dry matter (DM) results from high fat content (40% of DM). Piglets receiving ground linseed tended to higher feed consumption as well as body weight gain and lower feed to gain ratio. As a tendency the consumption of diet with solvent extracted linseed meal and the daily weight gain were lower than in control (without linseed meal). Linseed feedstuffs drastically increased thiocyanate concentration of blood serum. Cyanide is released and detoxified via sulphur transferases to thiocyanate in organism.Thiocyanate impairs thyroid function, however, only in case of iodine deficiency. In case of 0.5 mg/kg diet supplementary iodine in piglet's experiments ground linseed had no effect on thyroxine and triiodothyronine concentration oi blood serum. A lower serum thyroxine concentration of piglets which were given the solvent extracted linseed meal resulted from other causes than from iodine administration (0.5 mg/kg diet). 相似文献
10.
L. Stoloff A. D. Campbell A. C. Beckwith S. Nesheim J. S. Winbush Jr. O. M. Fordham Jr. 《Journal of the American Oil Chemists' Society》1969,46(12):678-684
Cases have been reported of individual peanuts, cottonseeds or Brazil nuts so highly contaminated with aflatoxin that, for
a 50 g portion to be representative of the whole, the sample preparation procedures should grind each unit to a large number
of particles and distribute them uniformly throughout the sample. Assuming uniform contamination of the individual kernel,
each 50 g sample should contain 1/100 of that kernel. Even though these extreme cases may be encountered only infrequently,
the more usual situation still presents difficulties because of great variability in individual kernel contamination. However,
if the extreme can be handled, one can expect to handle the more usual situation. Equipment and procedures to achieve this
distribution goal are described. The equipment studied includes a food chopper (Hobart), a nut mill (Thomas Mills), a disc
mill (Bauer), a hammer mill (Fitzpatrick Model D comminuting machine), a hammer mill designed specifically for peanut samples
(Dicken’s subsampling mill), a Polytron homogenizer (Bronwill Scientific), a vertical cutter-mixer (Hobart), and a sample
splitter (Jones riffle). Commodities examined were shelled peanuts and in-shell Brazil nuts, walnuts, pecans and almonds.
Comminution and mixing effectiveness were determined by particle size analysis, by distribution of kernels made radioactive
by neutron activation and by aflatoxin analysis of naturally contaminated products. From the results we conclude that the
ultimate in sample uniformity can be achieved with a disc mill, solvent addition to obtain a fluid system and mixing and grinding
of the fluid with a dispersion mixer-grinder. A practical uniformity can be achieved in a vertical cutter-mixer with less
expenditure of time and effort for the commodities studied.
Presented in part at the AOCS-AACC Joint Meeting, Washington, D.C., April 1968. 相似文献
11.
T. B. Whitaker J. W. Dickens R. J. Monroe E. H. Wiser 《Journal of the American Oil Chemists' Society》1972,49(10):590-593
Suitability of the negative binomial distribution for use in estimating the probabilities associated with sampling lots of
shelled peanuts for aflatoxin analysis has been studied. Large samples, called “minilots,” were drawn from 29 lots of shelled
peanuts contaminated with aflatoxin. These minilots were subdivided into ca. 12 lb samples which were analyzed for aflatoxin.
The mean and variance of these aflatoxin determinations for each minilot were determined. The shape parameterk and the mean aflatoxin concentrationm were estimated for each minilot. A regression analysis indicated the functional relationship betweenk andm to be:k=(2.0866+2.3898m) × 10−6. The observed distribution of sample concentrations from each of the 29 minilots was compared to the negative binomial distribution
by means of the Kolmogorov-Smirnov test. The null hypothesis that each of the true unknown distribution functions was negative
binomial was not rejected at the 5% significance level for all 29 comparisons.
Journal Series Paper of the North Carolina State University Agricultural Experiment Station, Raleigh, N.C. 相似文献
12.
James Velasco T. B. Whitaker M. E. Whitten 《Journal of the American Oil Chemists' Society》1975,52(6):191-195
Large samples called “sublots” were drawn from 41 commercial lots of contaminated cottonseed. Each sublot was subdivided into twenty 5 lb samples which were analyzed for aflatoxin. The mean, median, variance, coefficient of variation, and the estimated range among the sample concentrations were computed. The results indicated that: (A) the variance among sample concentrations was large and was found to be a function of sample concentration and (B) the distribution of sample concentrations was skewed; the density of sample values was greater below the sublot concentration. 相似文献
13.
James Velasco 《Journal of the American Oil Chemists' Society》1969,46(2):105-107
A simplified procedure for the detection of aflatoxin B1 in cottonseed meals has been developed. The procedure substantially reduces the time and cost of aflatoxin analysis. A single
chromatographic column of celite is used to concentrate and purify the aflatoxin fractions. A new solvent system of ether-methanol-water
(96:3:1) improves separation of aflatoxin fractions on TLC plates. This improvement permits measurement of B1 spots in one sweep of the plate with a densitometer using a 10–15 mm slit. The number of samples which can be screened for
aflatoxin contamination on one TLC plate is doubled by re-use of the plate. The use of technical reagents and stainless steel
beakers also helps reduce the time and cost of analysis. The procedure is sensitive to about 5 μg of B1 per kg of meal.
Presented at the joint meeting of the AOCS-AACC April, 1968, Washington, D.C. 相似文献
14.
The effect of the cotton storage trisaccharide raffinose and cottonseed storage protein (CSP) in combination on aflatoxin
production by Aspergillus flavus was investigated. The ability of ground whole cottonseed and water-extracted cottonseed meal to support fungal biosynthesis
of aflatoxin also was assessed in vitro. Dose response data showed that utilization of raffinose as a sole carbon source supported growth and aflatoxin production
by A. flavus. When raffinose was a carbon source and CSP was the sole nitrogen source, aflatoxin levels were stimulated up to fourfold
above those in raffinose reference media. Results with ground whole cottonseed as a sole carbon/nitrogen source demonstrated
the capacity for aflatoxin production in A. flavus cultures. Lipid extraction of ground whole seed severely reduced aflatoxigenesis potential; however, lipid extraction followed
by water extraction of ground whole seed restored much of the aflatoxin biosynthetic potential, suggesting the presence of
a water soluble inhibitory factor. Accessible carbon appeared to be the limiting resource in water-extracted meal, as a raffinose
supplement stimulated aflatoxin production. Either cottonseed storage lipid or raffinose was capable of providing accessible
carbon to A. flavus. Raffinose and CSP in developing and mature cottonseed may predispose seed to potentially high levels of aflatoxin contamination
by A. flavus upon seed infection. 相似文献
15.
建立了中性氧化铝固相萃取柱净化,超高效液相色谱-串联质谱法(UPLC-MS/MS)测定乳和乳制品中黄曲霉毒素M1的分析方法。样品经乙腈提取,乙酸锌辅助沉淀蛋白,中性氧化铝SPE柱净化,以乙腈和0.1%甲酸水溶液作为流动相进行梯度洗脱,以电喷雾离子源(ESI)在正离子多反应监测(MRM)模式下进行测定,外标法定量。结果表明,黄曲霉毒素M1在0.1~50μg/L浓度范围内呈良好的线性关系,相关系数(r2)大于0.99;空白样品加标回收率在70.8%~79.2%之间,相对标准偏差小于8%。方法检出限为0.02μg/kg,定量限为0.05μg/kg。该方法实用、准确、灵敏,适用于乳和乳制品中黄曲霉毒素M1的测定。 相似文献
16.
G. E. Onibi J. R. Scaife I. Murray V. R. Fowler 《Journal of the American Oil Chemists' Society》1998,75(2):189-198
Thirty-two pigs were allocated to one of four diets, FFRD0 and FFRD200, containing full-fat rapeseed (FFR), 150 g/kg [25–50
kg liveweight (LW)], and 250 g/kg (50–90 kg LW), or CD0 and CD200, containing equivalent quantities of rapeseed meal and 34
g/kg (25–50 kg LW) or 59.2 g/kg (50–90 kg LW) coconut oil and lard (0.5:0.5, w/w). Diets FFRD200 and CD200 were supplemented
with 200 mg/kg α-tocopherol acetate (ATA). ATA supplementation significantly (P<0.001) reduced muscle drip loss. The melting point (°C) of subcutaneous fat was significantly lowered by FFR (P<0.001) but increased by ATA supplementation (P<0.05). Tissue α-tocopherol (AT) concentrations were significantly increased by ATA supplementation. Longissimus dorsi AT concentration was positively correlated with AT concentration in subcutaneous fat (r=0.86) and in plasma at 35 (r=0.65) and 77 (r=0.85) days of feeding (P<0.001). In both L. dorsi and subcutaneous adipose tissue lipids, FFRD caused a significant (P<0.001) decrease in the ratio of n-6 to n-3 fatty acids and a significant (P<0.001) increase in the ratio of polyunsaturated to saturated fatty acids. AT supplementation significantly reduced the susceptibility
of L. dorsi and subcutaneous fat to lipid oxidation during storage at 4°C for up to 16 d. For all dietary treatments and storage times,
lipid oxidation [mg malondialdehyde (MDA)/kg muscle] was greater in the surface layer (0–2.5 mm) of L. dorsi than below the surface (2.5–5 mm). Oxidative stability of L. dorsi lipids to iron-induced lipid peroxidation was significantly improved (P<0.001) by AT supplementation. Meat from pigs fed FFRD diets was significantly less stable to iron-induced oxidation (nmoles
MDA/mg protein) at the longer incubation periods (100 and 200 min). The susceptibility of L. dorsi to iron-induced lipid oxidation decreased as the ratio of the tissue concentration of AT to unsaturated fatty acid increased. 相似文献
17.
Corn kernels that exhibited bright greenish-yellow fluorescence (BGYF) under long-wave ultraviolet light were hand-picked
from samples of yellow corn produced in eastern North Carolina. The BGYF kernels from 113 4-kg samples contained an average
of 8665 parts per billion (ppb) aflatoxin compared to an average of 46 ppb in the non-BGYF kernels. A regression analysis
between the ppb aflatoxin concentration and the wt % BGYF kernels in 2,304 4.5-kg samples produced the regression equation:
ppb in sample =197 (wt % BGYF). The correlation coefficient for the analysis was 0.90. Testing programs to reduce aflatoxin
concentrations in purchased lots of corn based on either the BGYF method or the AOAC chemical assay method were compared.
The average aflatoxin concentration in lots accepted by the AOAC method was 4 ppb, 10 ppb or 18 ppb when an acceptance level
of < 20 ppb, < 50 ppb or < 100 ppb, respectively, was used. For the BGYF method, the average aflatoxin concentration in accepted
lots was 10 ppb, 16 ppb or 22 ppb when an acceptance level of < 0.10% BGYF, < 0.25% BGYF or < 0.50% BGYF, respectively, was
used. Approximately the same percentage of lots were accepted by both methods when either the low, medium or high acceptance
level was used.
Paper no. 6930 of the Journal Series of the North Carolina Agriculture Research Service (NCARS), Raleigh, NC. 相似文献
18.
K. R. Natarajan K. C. Rhee C. M. Cater K. F. Mattil 《Journal of the American Oil Chemists' Society》1975,52(5):160-163
Sodium hypochlorite has been tested for destruction of aflatoxins during the preparation of peanut protein isolates from raw peanuts and defatted peanut meal. The treatments were evaluated by determination of the aflatoxins in the products by thin layer chromatography. Effects of sodium hypochlorite concentration, reaction pH, temperature, and time were studied. Results show that both the sodium hypochlorite concentration and pH are important factors in reducing the concentration of aflatoxins in the protein isolates to nondetectable levels. The treatment with 0.4% sodium hypochlorite at pH 8 produced protein isolates with trace amounts of aflatoxins B1 and B2 from ground raw peanuts containing 725 ppb aflatoxin B1 and 148 ppb aflatoxin B2, whereas untreated protein isolates contained 384 ppb aflatoxin B1 and 76 ppb aflatoxin B2. At pH 9, 0.3% sodium hypochlorite reduced the aflatoxin B1 content in the protein isolates from 300 ppb to below detectable quantities and the aflatoxin B2 content from 52 ppb to 2 ppb. Similar results were obtained at pH 10 for 0.3% sodium hypochlorite concentration. In the case of defatted peanut meal which contained 136 ppb aflatoxin B1 and 36 ppb aflatoxin B2, 0.25% sodium hypochlorite concentration at pH 8 (0.20% at pH 9; 0.15% at pH 10) reduced both the aflatoxin B1 and B2 contents to below detectable quantities in protein isolates as compared to aflatoxin levels of ca. 75 ppb B1 and 17 ppb B2 in the untreated protein isolates. Reaction temperature and time did not affect the destruction of aflatoxins significantly. 相似文献
19.
The effect of poultry species (broiler or turkey) and genotype (Wrolstad or BUT T8 turkeys and Ross 308 or Cobb 500 broilers)
on the efficiency with which dietary long-chain n−3 PUFA were incorporated into poultry meat was determined. Broilers and
turkeys of both genotypes were fed one of six diets varying in FA composition (two replicates per genotype x diet interaction).
Diets contained 50 g/kg added oil, which was either blended vegetable oil (control), orpartially replaced with linseed oil
(20 or 40 g/kg diet), fish oil (20 or 40 g/kg diet), or a mixture of the two (20 g linseed oil and 20 g fish oil/kg diet).
Feeds and samples of skinless breast and thigh meat were analyzed for FA. Worlstad dark meat was slightly more responsive
than BUT T8 (P=0.046) to increased dietary 18∶3 concentrations (slopes of 0.570 and 0.465, respectively). The Ross 308 was also slightly
more responsive than the Cobb 500 (P=0.002) in this parameter (slopes of 0.557 and 0.449). There were no other significant differences between the genotypes.
There was some evidence (based on the estimates of the slopes and their associated standard errors) that white turkey meat
was more responsive than white chicken meat to 20∶5 (slopes of 0.504 and 0.289 for turkeys and broilers, respectively). There
was no relationship between dietary 18∶3 n−3 content and meat 20∶5 and 22∶6 contents. If birds do convert 18∶3 to higher FA,
these acids are not then deposited in the edible tissues. 相似文献
20.
Experiments were conducted to evaluate the potential use of mustard meal as organic fertiliser on tef (Eragrostis tef (Zucc) Trotter). Mustard meal is a high quality nutrient source with 6.35% lignin, 2.1% total extractable polyphenol, C to
N ratio of 14 and lignin to N ratio of 1.1. Under field conditions the effect of tef on Nitosol was studied in a split plot
design with three replications. Grain yield increases due to increased mustard meal N rate varied from 2 to 116% over the
control. The agronomic efficiency was 3.0, 8.3 and 13.5 kg when N was applied at 15, 23 and 31 kg ha−1, respectively. The mustard meal N use efficiency was 7.6, 20.6 and 33.7% for the above-indicated N rates. Application of
mustard meal in powder form was more effective than granular. In the greenhouse, the effect of mustard meal and urea N mixed
in different quantity was studied with 15N technique. The N derived from fertiliser was lowest (3.5%) when 20 mg pot−1 from urea was combined with 100 mg pot−1 from mustard meal and highest (11%) when 67 and 33 mg pot−1 as urea and mustard meal were combined, respectively. The N derived from mustard meal was lowest (3.3%) when mustard meal
and urea N were combined at 50 mg N pot −1 each, and highest (8.9%) when combined at 20 and 100 mg N pot−1, respectively. The urea and mustard meal N yields significantly varied between the treatments. The N use efficiency from
urea (FNUE) varied from 38.4 to 43%. Combining urea and mustard meal N at 50 mg N pot−1 each has decreased FNUE to 4.4% compared to the urea N applied alone at 50 mg N pot−1. N use efficiency (NUE) from mustard meal was highest (38.4%) when mustard meal and urea N were combined at 33 and 67 mg N pot−1, respectively, and lowest when it was combined at 67 and 33 mg N pot−1. 相似文献