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1.
In order to determine the distribution of mycotoxin contamination in Bavaria, Germany, and to control the quality of feed cereals the three toxins, deoxynivalenol (DON), ochratoxin A (OTA), and zearalenone (ZEA) from 5 different cereals out of 5 districts were analysed. Our investigation demonstrates that all data are near the discussed guide values thus the quality of cereals was not affected seriously in 1999. Calculating the medians for the 5 districts separately it was possible to establish a rough grid revealing a more detailed view on the mycotoxin situation in Bavaria.  相似文献   

2.
Of 88 isolates of Fusarium graminearum collected from soil or cereals in the United States, 49 produced 15-acetyldeoxynivalenol (15-ADON) as the major isomer; one produced 3-acetyldeoxynivalenol (3-ADON). A total of 26 isolates collected from cereals or soil in Australia, New Zealand, Norway, China, and Poland were used for comparison. Of these, 15 produced 3-ADON as the major isomer and 2 produced 15-ADON.  相似文献   

3.
An ethnoarchaeological study of highland Ethiopian griddle technology is compared to bread-baking technologies in Africa and the Near East. There is a functional relationship between the use of ovens and griddles and the presence or absence of gluten in bread ingredients. Ovens are most appropriate for cereals containing gluten and may be implicated in the selection of higher quality gluten in domesticated wheats. We conclude, based on evidence for griddle use and the performance characteristics of African cereals, that indigenous species were exploited in highland Ethiopia before Near Eastern cereals were introduced. Griddle-cooking practices that bias the preservation of Near Eastern cereals over African ones may explain the absence of African cereals in the early archaeobotanical record. [Keywords: Ethiopia, ethnoarchaeology, archaeobotany, ovens, griddles]  相似文献   

4.
Minerals can enter the food chain through industrial and mining activities. Soil-to-vegetable transfer is higher than soil-to-cereal, but human consumption of metals is attributable to balanced diets containing both vegetables and cereals and drinking water. However, the impact of location on intakes of metals from predominantly cereal-based Indian diets is not clear. Hence, the present study was undertaken in selected Agricultural, Industrial, and Coal Mining Areas (AA, IA, CMA) around the Allahabad District in Northern India to compare transfer of toxic metals, Pb, Cd, Cr and essential metals, Fe, Zn, Cu, Co in soil and water to common crops: cereals (rice, wheat, maize) and vegetables (spinach, potato), and to assess Daily Intake of Metal (DIM) and consequent Health Risk Index (HRI). The overall content of all metals, except Cu, in water, soils, and crops followed the pattern CMA > IA > AA. Transfer factors (TFs) followed the sequence spinach > potato > cereals. Quantitatively, however, cereals contribute maximally to a balanced diet, so DIM and HRI were higher from cereals than vegetables. Even though spinach had the highest TFs, cereals contributed maximally to HRI. CMA had the highest metal content so locally grown cereals contributed significantly to intake of both toxic and essential metals.  相似文献   

5.
Barley yellow dwarf virus (BYDV) was detected in forage cereals and small grain cereals by indirect enzyme-linked immunosorbent assay. Samples of forage cereals collected in the winters of 1987/1988, 1988/1989 and 1989/1990 showed that this crop is a reservoir of BYDV during the end of summer and autumn. PAV-like and MAV-like isolates, in single or mixed infection, were the most common. The proportion of isolates in the infected samples was relatively stable, Samples of winter cereals collected in the springs of 1988, 1989 and 1990 showed that PAV- and MAV-like isolates were widespread. The proportion of samples infected with PAV-like isolates was much more variable than that of MAV-like isolates. The incidence of PAV-like isolates in winter cereals is more dependent on the population of Rhopalosiphum padi during the winter and early spring, than is the incidence of MAV-like isolates on Sitobion avenae density. In northeast Spain (Lleida basin) forage cereals are a constant source of PAV- and MAV- like isolates from which BYDV inoculum is introduced into winter cereals.  相似文献   

6.
Six experiments on growing rats were conducted to measure the nutritive value of diets based on cereals (wheat and barley, 1:1) and ethanol-grown yeast. Optimum protein provision in isonitrogenous diets (11.3% crude protein) determined on the basis of live weight gain, feed efficiency and protein efficiency ratio was found to be 60 and 40% for cereal and yeast protein, respectively, corresponding to a diet containing 84.5% cereals and 13.2% yeast (Experiments 1 and 2). The addition of single amino acids (l-lysine, 0.05–0.15%; dl-methionine, 0.1–0.3%) or their combinations (l-lysine + dl-methionine, 0.05 + 0.1%; 0.1 + 0.1%; 0.05 + 0.2%; and 0.1 + 0.2%) to the diet containing 13.2% yeast had no significant effect on either growth rate or feed efficiency (Experiments 3 and 4). A non-fortified diet alone proved to be comparable in nutritive value to a standard diet containing high-quality protein components.The diet with yeast providing 20% and cereals providing 80% of the total protein (5.55% yeast, 92.15% cereals) with combined supplement of amino acids (dl-methionine 0.2% + l-lysine 0.2% + l-isoleucine 0.1%; Experiment 5) promoted growth rate and feed efficiency similar to the standard diet, in spite of the fact that the experimental diet protein-content was about 3% lower. In a separate experiment (Experiment 6), similar results were achieved with the supplement of l-lysine alone (0.15% of the diet).As suggested by the results of model experiments on rats, the nutritive value of diets based on cereals and ethanol-grown yeast, possibly supplemented with amino acids, is comparable with that of diets containing animal protein components.  相似文献   

7.
Experiments were performed to compare the composition and nutritive value of mixtures containing leaf protein coagulum from lucerne with cereals (ground barley, ground wheat and wheat bran), with non-processed cereals alone or with the addition of separately-dried leaf protein. The chemical composition of mixtures and amino acid composition of their proteins were determined by conventional methods. The biological value and true digestibility of cereals and mixture proteins were determined on rats by the Thomas-Mitchell balance method.The biological values of mixture proteins were higher, but their digestibility was lower, than those of cereals alone. Generally, better results were obtained when cereals were mixed with separately-dried leaf protein and with barley rather than wheat.  相似文献   

8.
Summary The translocation of cesium from leaves into the edible parts after foliar deposition at different stages of growth has been determined for cereals, potatoes, green beans and carrots in field experiments. For all the plant species investigated a significant seasonality of the cesium translocation was observed. The highest translocation factors were determined after foliar contamination 50 to 60 days before harvest for cereals, and 70 to 90 days and 15 days before harvest for potatoes and green beans, respectively. The variations among the different experiments can be reduced when the translocation is normalized to the yield. This facilitates the application in probabilistic models due to the implicit consideration of the relationship between translocation and yield. The seasonality of the cesium translocation can be described with gaussian functions being consistent with the physiological development of cereals and potatoes. The uncertainty of these approaches is a factor of 3 and 4 for cereals and potatoes, respectively.  相似文献   

9.
1. Surveys have shown that there has been a dramatic decrease in the weed flora of fields under rotational cultivation during the last 30 years. This trend has been particularly noticeable in winter cereals, a crop of increasing importance in the landscape.
2. The weed flora of spring and winter cereals was compared in 19 unsprayed fields during a 5-year study to test the hypothesis that cereal type exerts no effect on the flora or on the absolute and relative abundance of single species.
3. Plant and species densities, and accumulated species richness, were lower in winter than in spring cereals.
4. Floristic similarity was greater among spring cereal fields and between spring and winter cereals within the same fields than among winter cereal fields.
5. Species that occurred with unequal density in spring and winter cereals occurred at higher densities in the spring cereals; these species germinated mainly in the spring. However, for a few species the relative plant abundance was highest in winter cereals; these species were able to germinate both in the spring and autumn.
6. Some species – on the relative scale – occurred indifferently of season of sowing; all but one of these species were able to germinate both in the spring and autumn.
7. Plant species and taxa that are important food resources for arthropod herbivores occurred at greater densities in spring than in winter cereals and, in addition, occurred with the highest relative abundance in spring cereals.
8. Change in land use from spring to winter cereals involves not only an immediate reduction of more than 25% in the density of plants and species, but also a change and increased uncertainty in the composition of the weed flora. These findings may have serious implications for the ecology of wildlife in the agricultural landscape.  相似文献   

10.
The urban archaeological excavations carried out in the city of Lleida (Catalonia, Spain) have opened the way for an interdisciplinary project on the ancient landscape, agriculture and food. Here we present the results of the archaeobotanical study of seeds and fruits from this project, centred on the Roman and Islamic periods of the city, between the 2nd century B.C. and the 11th century A.D. During the whole of this period the cultivation and consumption of cereals was found. The most important cereals were hulled barley and naked wheat. This was already known from the later prehistoric era in the area and is similar to findings at other sites from the same period in the western Mediterranean. These cereals are accompanied by some leguminous crops and the presence of grapes and figs is very significant. The expansion of vine cultivation, together with a certain amount of tree growing was one of the basic contributions of the Roman world to proto-historical (Bronze- and Iron Age) agriculture in western Catalonia, as in other parts of Europe. In the Islamic period, there seems to have been an increase in the number of fruit tree species; however for taphonomical reasons this has to be confirmed by future investigations. Flax, already known in prehistoric times, and Gold-of-pleasure must be added to the finds. Also since the Roman period some other taxa, such as celery or fennel, might have been grown. During the time period considered in this paper, there was a wide range of plants grown and consumed. This clearly contrasts with everything known about earlier periods in western Catalonia, during which the only cultivated plants were cereals and flax.  相似文献   

11.
Catt  J.A.  Howse  K.R.  Christian  D.G.  Lane  P.W.  Harris  G.L.  Goss  M.J. 《Plant and Soil》1998,203(1):57-69
Nitrate losses in drainflow were measured over five years on eight hydrologically isolated field plots, pairs of which had the following cropping regimes: (a) a 3-yr unfertilised, ungrazed grass ley followed by winter and spring cereals, (b) mixed cropping including winter cover crops, spring cereals, winter cereals, winter fallow and spring beans, (c) a similar sequence to (b) but with a winter fallow replacing the cover crop in the first year and a winter cover crop replacing the fallow in the third year, and (d) continuous winter cereals (control plots). Less nitrate was lost in winter drainflow from winter cover crops than from the winter fallows, but over all five years less nitrate was leached from the continuous cereal plots than from those with mixed cropping. Most of the extra nitrate lost from the mixed cropping regimes probably resulted from mineralisation of the cover crop residues, which occurred at times when subsequent crops could not take advantage of the mineral nitrogen released. Crops grown after the grass ley and cover crops did not benefit from their residues, in terms of either grain yield or of total nitrogen uptake. We conclude that on heavy clay soils in UK a cropping regime of continuous winter cereals offers the best compromise between profitable crop production and minimised nitrate loss to surface waters.  相似文献   

12.
Different solvent mixtures were examined for extraction of fumonisins from various naturally contaminated and spiked foods and foodstuffs: rough rice, retail rice, rice flour, white corn flour, corn meal, corn starch, corn flakes, tortilla/corn chips, white bean flour, white beans, mung beans, adzuki beans and infant cereals. Most of the naturally contaminated samples were analyzed using the extraction solvent mixtures methanol-acetonitrile-water (25:25:50) (solvent A) and methanol-water (75:25 or 80:20) (solvents B, BB); some were extracted with 0.1 M sodium hydrogen phosphate-acetonitrile (1:1, adjusted to pH 3.0 with o-phosphoric acid) (solvent C) and methanol-0.025 M borate buffer (3:1, adjusted to pH 9.2 with 1 N sodium hydroxide) (solvent D). A 1-ml SAX solid phase extraction column was used for the cleanup in all cases except for infant cereals, for which immunoaffinity chromatography was used; fumonisin concentrations were determined by liquid chromatography. Solvent A gave slightly better extraction of fumonisins from one of two samples of naturally contaminated rough rice than solvent B (fumonisin B1: 4080 ng/g versus 3150 ng/g; fumonisin B2:1100 ng/ g versus 922 ng/g) and much better extraction than solvent C (1210 ng/g fumonisin B1 and 315 ng/g fumonisin B2) or solvent D (372 ng/ g fumonisin B1 and 191 ng/g fumonisin B2). However, spike recoveries on a similar rice naturally contaminated at a lower level were only in the 43–53% range (solvent A). Recovery of fumonisins was very poor from spiked white rice flour but satisfactory from other rice foods. Solvent A similarly gave slightly better extraction of fumonisins from a sample of naturally contaminated white corn flour than solvent B (fumonisin B1 1260 ng/g versus 931 ng/g; fumonisin B2: 511 ng/g versus 447 ng/g ) and better extraction than solvents C and D. Solvent A was also a better solvent for extraction of fumonisins from naturally contaminated tortilla chips and infant cereals. Study of naturally contaminated corn starch was confounded by instability of fumonisins in this food. Recovery of fumonisins from spiked corn meal, tortilla chips, corn flakes, various types of beans and infant cereals with solvent A and/or solvent B (or BB) was satisfactory.  相似文献   

13.
Fluoride is a potentially toxic element, with a narrow range of tolerable amounts taken up via food or drinking water. To evaluate F content in surface soils, 255 topsoil samples (0–20 cm) in an area of 6800 km2 in Isfahan province of central Iran were collected. Crop plants and randomly sampled water samples from wells were evaluated during the spring and summer seasons. Total F concentration in 96% of soil samples was lower than the global suggested average of 200 mg kg?1. The mean F concentration of water samples in the study area was 0.05 and 0.3 mg L?1 in summer and spring, respectively. Fluoride concentrations in different plant species were in the range of normal values. The total hazard quotient (HQ) for both population groups via consumption of cereals, vegetables, and water; incidental ingestion of soil; inhalation of soil particulates; and dermal contact with water and soil was less than 1.0, resembling no obvious risk. It is suggested that neither age group in Isfahan province will experience a significant potential health risk through their dietary intake of cereals, vegetables, and water; ingestion of soil; inhalation of particulates; and dermal contact.  相似文献   

14.
The archaeobotanical investigations in the Neolithic pile settlement of Hornstaad Hörnle I A, Lake Constance, Germany (3919–3905 cal B.C.) has answered many questions concerning agricultural activities and land use in Neolithic times. Very large carbonized stores of unthreshed cereals there showed that every household had 210–280 kg of naked wheat, einkorn, barley and emmer. As most of the wild plant remains in the cereal stores were from annual field weeds it is concluded that the arable land was cultivated continuously, probably for the whole duration of the settlement's occupation. No hints of short or long period fallows were found. Intensive soil treatment such as hoeing and digging is indicated by the rarity of perennial weeds. Because of the high quality of the cultivated soils, manuring was not necessary. The cereals were harvested high on the culm, and the harvest was first stored unthreshed, probably to dry it completely. Every house (family) had its own cereal stores with various cereals. Naked wheat and probably naked barley were threshed outside the settlement, while dehusking of einkorn and probably of emmer took place inside the village. Evidence of cereal cleaning, winnowing, sieving and sorting by hand were found. More than 700 carbonized remains of food products showed that porridge made from ground and shredded wheat was one of the main foods in the settlement.  相似文献   

15.
This paper analyses data from 995 Skylark Alauda arvensis nests found on lowland farms in southern England from 1996 to 1998. The majority of recorded nest failures were caused by predation except in agricultural grass, where trampling and agricultural operations were equally important. Nest survival rates varied between crop types, nests in cereals being around twice as likely to succeed as nests in grass or set-aside. In cereals, nest survival rates increased with increasing distance from the nearest tramline and declined over the course of the breeding season. Predator control also had a significant independent effect on nest survival rates. On one farm where many other factors were held constant, a highly significant increase in nest survival rates from 12.3% to 40.7% coincided with the introduction of intensive predator control, which also appeared to bring forward mean laying dates. Most environmental factors explaining significant variation in nest survival rates did so only at the chick stage. The mean number of chicks produced per nesting attempt was 1.26 in cereals, 0.78 in set-aside and 0.63 in grass, the differences being due primarily to variation in nest survival rates. Low densities of Skylark territories in cereal crops are not therefore the consequence of low breeding success at the scale of the individual nest and probably reflect limitations on the number of attempts made in a season. Measures taken to improve the attractiveness of cereal crops as a nesting habitat for Skylarks, and beneficial changes in grassland management, are likely to increase overall productivity.  相似文献   

16.
Lithium was used as a non-radioactive tracer to investigate the root activity of two cereals (wheat and barley), and of two contrasting cultivars of pea (leafy and semi-leafless), both in pure stands and in mixtures. The mixtures included combinations of each cereal with each pea cultivar in single rows, alternative rows and cross-drilled. Total lithium uptake (mg m-2) was higher for wheat than for barley, and higher for semi-leafless pea than for leafy peas. Growing cereals with peas reduced the total lithium uptake by peas, compared with pure stands, especially in alternate-row mixtures. Growing peas with cereals only reduced the total Li uptake by cereals when they were cross-drilled. The Li uptake by wheat, barley and peas generally decreased with soil depth in a similar manner; however, semi-leafless peas absorbed proportionately more Li from close to the soil surface than did leafy peas. Both pea cultivars absorbed more Li at 10–20 cm depth when grown in intimate mixtures with cereals, compared with less intimate mixtures or pure stands. The potential of lithium as a non-radioactive tracer in mixed-cropping studies is briefly discussed.  相似文献   

17.
BackgroundComplementary feeding of breastfed infants with foods high in bioavailable zinc (Zn) can help meet physiological requirements for Zn. Some infant cereals contain high concentrations of phytic acid (PA) and calcium (Ca) that may reduce absorbable Zn.ObjectivesThis study measured PA, Zn and Ca concentrations in selected infant cereals sold in Canada and investigated the effects of dietary PA and Ca at concentrations present in infant cereals on Zn bioavailability in rats.Methods and resultsMale Sprague-Dawley rats (36-day old) were fed a control diet containing normal Zn (29.1 mg/kg) and Ca (4.95 g/kg) or six test diets (n = 12/diet group). Test diets were low in Zn (8.91–9.74 mg/kg) and contained low (2.16–2.17 g/kg), normal (5.00–5.11 g/kg) or high (14.6–14.9 g/kg) Ca without or with added PA (8 g/kg). After 2 weeks, rats were killed and Zn status of the rats was assessed. PA, Zn and Ca concentrations in infant cereals (n = 20) differed widely. PA concentrations ranged from undetectable to 16.0 g/kg. Zn and Ca concentrations ranged from 7.0–29.1 mg/kg and 0.8–13.4 g/kg, respectively. The [PA]/[Zn] and [PA × Ca]/[Zn] molar ratios in infants cereals with detectable PA (16 of 20 cereals) ranged from 22–75 and 0.9–14.9 mol/kg, respectively, predicting low Zn bioavailability. Body weight, body composition (lean and fat mass), right femur weight and length measurements and Zn concentrations in serum and femur indicated that diets higher in Ca had a more pronounced negative effect on Zn status of rats fed a PA-supplemented diet. Addition of PA to the diet had a greater negative effect on Zn status when Ca concentration in the diet was higher.ConclusionThese results show that, in rats, higher concentrations of dietary Ca and PA interact to potentiate a decrease in bioavailable Zn and may suggest lower Zn bioavailability in infant cereals with higher PA and Ca concentrations.  相似文献   

18.
Among the cereals, rye (Secale cereale L.) can be grown under extreme climatic and poor soil conditions and, is a major crop in North Europe. In the present paper, we report the development of a genetic linkage map of rye using a pooled F2 mapping population created from a reciprocal cross of two self-fertile inbred lines. The 183 mapped markers consist 139 RFLPs, 19 isozyme and protein markers, 13 microsatellites, 10 known function sequences and two morphological genes. The markers are randomly distributed on the seven chromosomes with a maximum of 38 on chromosome 5R and a minimum of 19 on chromosome 3R. In addition, 23 gene loci and 25 quantitative trait loci were aligned to chromosome regions. For some of the mapped or aligned genes comparable loci are present in other cereals. The homoeologous relationships of these loci are discussed. The potential of the new map for further genetic studies is outlined. Received: 11 May 2000 / Accepted: 12 July 2000  相似文献   

19.
Two field trials were conducted to investigate different herbage grasses and cereals for their susceptibility to the disease take‐all, for their impact on concentrations of the pathogen, Gaeumannomyces graminis var. tritici (Ggt), in soil and for their effect on development of take‐all in a subsequent wheat crop. In the herbage grass trial, Bromus willdenowii was highly susceptible to Ggt, produced the greatest post‐senescence Ggt concentrations in soil and highest incidence of take‐all in following wheat crop. Lolium perenne, Lolium multiflorum and Festuca arundinacea supported low Ggt soil concentrations and fallow the least. The relationship between susceptibility to Ggt and post‐senescence concentrations in soil differed between pasture grasses and cereals. In a trial in which Ggt was added to half the plots and where wheat, barley, triticale, rye or fallow were compared, the susceptibility of the cereals to take‐all was not clearly linked to post‐harvest soil Ggt concentrations. In particular, triticale and rye had low and negligible take‐all infection respectively, but greater post‐harvest soil Ggt concentrations than barley or wheat. This indicates that low Ggt concentrations on roots may build up during crop senescence on some cereals. Soil Ggt concentrations were greater following harvest in inoculated plots sown to cereals, but in the second year there was more take‐all in the previously non‐inoculated than inoculated plots. Thus, the grass and cereal species differed in susceptibility to take‐all, in their impact on Ggt multiplication and in associated take‐all severity in following wheat crop.  相似文献   

20.
The isotopic composition of the remains of cereals and pine has been studied, from three different chronological phases from 2140 to 1500 cal bc at the Terlinques site, southeast Iberian Peninsula. The δ13C values range between ?24.91 and ?21.19 ‰ (V-PDB), with an average of ?23.05 ‰ (STD = 0.69). The archaeological cereals show an average isotopic discrimination (Δ13C) with the past atmospheric CO2 of 16.96 ‰, which is much greater than the average Δ13C of 13.89 ‰ of the rainfed Triticeae (wheat and barley) in modern times. However, considering the effect of the atmospheric CO2 concentration, which is included in the WUEi (intrinsic water-use efficiency), this difference is even greater, 77 for archaeological samples versus 144 for present-day rainfed cereals. This could represent some of the earliest evidence of the use of irrigation techniques in Europe. Modern cereals which have been irrigated show a general Δ13C average of 17.17 ‰, very similar to those of the middle Holocene. However, when the WUEi is calculated, the value of 108 indicates that present-day irrigated cereals are more stressed than the archaeological samples. For comparison, we have included pine trees, since these have an extensive root development which is capable of reaching the water table. In the past, both cereals and pine present similar WUEi values (77 vs. 72), however at present only irrigated cereals show similar WUEi values to pine (108 vs. 107). This again suggests irrigation of cereals in the past. The processes of climatic degradation towards drier conditions which started in the middle Holocene could be responsible for the use of land near water sources, on riverbanks and near shallow lakes. According to the isotopic and plant macrofossil data, irrigation or water management techniques were used at the Terlinques site, located close to the Laguna de Villena, a lake which has now dried out.  相似文献   

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