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Barley
Kinds of Barley Terms modified by Barley Selected AbstractsPUFFING AND JET COOKING AFFECT SOLUBILITY AND MOLECULAR WEIGHT OF BARLEY ,-GLUCANS,JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 6 2004A.P. KLAMCZYNSKI ABSTRACT Foods containing barley or oats are often marketed as healthy because of the dietary fiber (1,3) (1,4)-,-D-glucan. Processing conditions can affect the molecular structure of these dietary fibers, which in turn affect quality and properties of the products. In this study, the effect of puffing and jet cooking conditions on changes in the solubility and molecular weight of barley ,-glucans was investigated. Barley flour was processed in a pasta extruder to produce particles similar in size and shape to rice. These particles were puffed at 230, 250 and 270C for 6, 8 and 10 s in a rice cake machine. Solubility and molecular weight of barley ,-glucans were determined by using water extracts (25 or 65C). The amount of ,-glucan extracted in water at 25C increased from 41.1% in cakes puffed at 230C/6 s to 69.7% in cakes puffed at 270C/10 s. The amount of ,-glucan extracted in water at 65C increased from 63.6% in samples puffed at 230C/6 s to 99.1% in samples puffed at 270C/10 s. The molecular weight of ,-glucans in barley was reduced by puffing and jet cooking treatments. [source] Optimal Hedging Ratios for Wheat and Barley at the LIFFE: A GARCH ApproachJOURNAL OF AGRICULTURAL ECONOMICS, Issue 2 2000P. J. Dawson Over 100,000 futures contracts for cereals are traded annually on the London International Financial Futures Exchange. The proportion of the spot position held as futures contracts - the hedging ratio - is critical to traders and traditional estimates, using OLS, are constant over time. In this paper, we estimate time-varying hedging ratios for wheat and barley contracts using a multivariate generalised autoregressive conditional heteroscedasticity (GARCH) model. Results indicate that GARCH hedging ratios do change through time. Moreover, risk using the GARCH hedge is reduced significantly by around 4 per cent for wheat and 2 per cent for barley relative to the no hedge position, and significantly by around 0.2 per cent relative to the constant hedge. The optimal, expected utility-maximising, and the risk-minimising hedging ratios are equivalent. [source] Evaluation of Drought-Related Traits and Screening Methods at Different Developmental Stages in Spring BarleyJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 5 2008F. Szira Abstract Despite intensive research and breeding efforts, the physiological and quantitative genetic bases of drought tolerance are still poorly understood. The comparison of results obtained from different sources is also complex, because different testing methods may lead to controversial conclusions. This report discusses various drought stress experiments (hydroponics and in soil) in which the plant tolerance was studied at different developmental stages. Tests were performed in the germination, seedling and adult plant stages on the parental lines of five well-known barley-mapping populations. The results suggest that drought tolerance is a stage-specific trait and changes during the life cycle. The effect of drought stress depended not only on the duration and intensity of water deficiency, but also on the developmental phase in which it began. To induce the same type of stress and to obtain comparable tolerance information from the replications, it is recommended that drought stress should be induced at the same growth stage. Correlations between the traits, commonly associated with improved drought resistance (high relative water content under stress, proline accumulation, osmoregulation) with stress tolerance indexes, are also presented, while the advantages and disadvantages of the most frequently used screening methods are discussed. [source] Effects of 15N Split-application on Soil and Fertiliser N Uptake of Barley, Oilseed Rape and Wheat in Different Cropping SystemsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2007K. Sieling Abstract In intensive farming systems, farmers split up and apply the N fertilization to winter cereals and oilseed rape (OSR) at several dates to meet the need of the crop more precisely. Our objective was to determine how prior fertilizer N application as slurry and/or mineral N affects contributions of fertilizer- and soil-derived N to N uptake of barley (1997), oilseed rape (OSR; 1998) and wheat (1999). In addition, residual fertilizer N effects were observed in the subsequent crop. Since autumn 1991, slurry (none, slurry in autumn, in spring, in autumn plus in spring) and mineral N fertilizer (0, 12 and 24 g N m,2) were applied annually. Each year, the treatments were located on the same plots. In 1997,1999, the splitting rates of the mineral N fertilization were labelled with 15N. Non-fertilizer N uptake was estimated from the total N uptake and the fertilizer 15N uptake. All three crops utilized the splitting rates differently depending on the time of application. Uptake of N derived from the first N rate applied at the beginning of spring growth was poorer than that from the second splitting rate applied at stem elongation (cereals) or third splitting rate applied at ear emergence or bud formation (all three crops). In contrast, N applied later in the growing season was taken up more quickly, resulting in higher fertilizer N-use efficiency. Mineral N fertilization of 24 g N m,2 increased significantly non-fertilizer N uptake of barley and OSR at most of the sampling dates during the growing season. In cereals, slurry changed the contribution of non-fertilizer N to the grain N content only if applied in spring, while OSR utilized more autumn slurry N. In OSR and wheat, only small residual effects occurred. The results indicate that 7 years of varying N fertilization did not change the contribution of soil N to crop N uptake. [source] Yield Responsiveness in Two- and Six-Rowed Barley Grown in Contrasting Nitrogen EnvironmentsJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2006S. Arisnabarreta Abstract Two- and six-rowed barley with different intrinsic ability to produce tillers and kernels per ear, would differ in responsiveness to nitrogen availability with environmental improvements. Two field experiments were carried out to elucidate how nitrogen supply (N40 and N150) affects yield and its components in two- and six-rowed barley. High nitrogen increased aboveground dry matter at anthesis, by improving cumulative solar radiation intercepted by the crop, determining an increased dry-matter production at maturity without changes in harvest index. In both barley types, variations in grain yield were explained by changes in kernels per unit land area rather than by differences in the average kernel weight. However, changes in the number of kernels were due to variations in the number of ears per m2 in two-rowed barley and the number of kernels per ear in six-rowed barley. Ears per unit area showed a greater responsiveness in two- than in six-rowed barley due to a higher nitrogen supply treatment, associated with their intrinsic higher tillering capacity, while the number of kernels per ear was more responsive in six- than in two-rowed types. The fact that responses to nitrogen by the number of kernels per unit land area in two- and six-rowed barley is better explained by different yield sub-components, allows the speculation that the critical period for yield determination would differ between barley types. [source] Barley Autotoxicity as Influenced by Varietal and Seasonal VariationJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2005O. Oueslati Abstract Barley (Hordeum vulgare L.) is widely cultivated in the semi-arid region of Tunisia for grain production and grazing, which often occurs during the same season. We previously demonstrated autotoxic effects of barley among varieties. The present study was conducted to test the effects of barley variety and seasonal variation on the expression of autotoxicity by barley. Four barley varieties were grown in a field experiment over three growing seasons (1999,2000, 2000,01, 2001,02). In the laboratory, germination and seedling growth bioassays were used to assess autotoxicity potential of field-harvested barley. Barley autotoxicity was fully expressed based on inhibition of radicle growth detected in seedling bioassays. Stems were often the most allelopathic plant component. Allelopathic activity of the barley varieties differed across growing seasons suggesting the influence of a seasonal effect due to the extent of water deficit during the dry season and monthly rainfall variability. The results suggest that when planning to integrate barley within cropping sequences, barley producers should carefully select appropriate barley varieties to minimize autotoxicity, which can be more severe under drought conditions. [source] Impact of Soil Tillage and Crop Rotation on Barley (Hordeum vulgare) and Weeds in a Semi-arid EnvironmentJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 6 2004H. Z. Ghosheh Abstract Experiments were conducted to evaluate the effect of mouldboard- or chisel-ploughing and rotations on barley crops and associated weeds in a semi-arid location. Two primary soil tillage operations and eight crop rotation-tillage operation combinations were evaluated over two successive seasons. Drought conditions prevailed (<152 mm annual precipitation) and affected the measured parameters. Barley grown in mouldboard-ploughed plots had higher biomass compared with chisel-ploughed plots. Barley grain yield was greater in mouldboard-ploughed plots in a fallow-fallow-barley rotation. Weed species densities varied between tillage systems and rotations. Density of Hordeum marinum, for example, was high in fallow-barley-fallow in chisel-ploughed plots, and was high under more continuous fallow in mouldboard-ploughed plots. Similar variations were also observed in weed fresh weights and in numbers of seed produced. The results describe the productivity of barley under extremely dry conditions, where an advantage for mouldboard ploughing was observed. The results also indicate the complexity of weed communities in their response towards different tillage-rotation combinations. [source] Spring Cereals for Forage and Grain Production in a Cool Maritime ClimateJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2003A. G. Todd Abstract Newfoundland's climate is marginal for agricultural production. The availability of locally grown cereal grain and high-quality forage are major limitations to successful animal agriculture in this region. Here, our overall objective was to compare several spring cereal species for both annual forage and grain production in Newfoundland's cool Maritime climate. Several varieties of barley (Hordeum vulgare L.), wheat (Triticum aesitivum L.), oats (Avena sativa L.) and pea (Pisum sativum L.),cereal mixtures for forage yield and quality, as well as grain yield and maturity, were compared in field trials on the east and west coasts in both 1999 and 2000. Barley headed earliest, yielded greatest forage dry matter, had lowest forage protein and acid detergent fibre (ADF) percentages, and had neutral detergent fibre (NDF) mean values greater than those of pea,cereal mixtures, but less than those of oats and wheat. Forage harvested from pea,cereal mixtures was similar to that of barley for yield, ADF and NDF, while P and protein percentage were much greater. Barley matured 10,15 days earlier than both wheat and oats. In general terms, all three spring cereals exhibited similar grain yield potential. Oats tillered less, but compensated by producing more kernels spike,1. Days to maturity for cereal grains in western Newfoundland were roughly similar to those reported for the Maritime provinces of Canada. Yield and maturity results for both forage and grain production suggest that eastern Newfoundland is a unique agro-ecoregion in North America, and agronomic recommendations specific to other regions may not be applicable in this region. [source] Effects of Salinity and Mixed Ammonium and Nitrate Nutrition on the Growth and Nitrogen Utilization of BarleyJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2001A. Ali The absorption and utilization of nitrogen (N) by plants are affected by salinity and the form of N in the root medium. A hydroponic study was conducted under controlled conditions to investigate growth and N uptake by barley (Hordeum vulgare L.) supplied with five different NH4+ -N/NO3, -N ratios at electrical conductivity of 0 and 8 dS m,1. The five NH4+ -N/NO3 -N ratios were 0/100, 25/75, 50/50, 75/25 and 100/0, each giving a total N supply of 100 mg N l,1 in the root medium. A mixed N supply of NH4+ and NO3, resulted in greater accumulation of N in plants than either NO3, or NH4+ as the sole N source. Plants produced a significantly higher dry matter yield when grown with mixed N nutrition than with NH4+ or NO3, alone. Total dry matter production and root and shoot N contents decreased with increasing salinity in the root medium. The interaction between salinity and N nutrition was found to be significant for all the variables. A significant positive correlation (r=0.97) was found between nitrogen level in the plant shoot and its dry matter yield. Wachstum und Stickstoffausnutzung bei Gerste in Abhängigkeit von Versalzung und Michungen von Ammonium und Nitrat Aufnahme und Nutzung von N durch Pflanzen wird von der Versalzung und N-Form im Wurzelbereich bestimmt. Es wurde in Hydrokultur unter kontrollierten Bedingungen Wachstum und N-Aufnahme durch Gerste (Hordeum vulgare L.) bei Anwendung von fünf unterschiedlichen NH4+ -N/NO3, -N Verhältnissen bei einer elektrischen Konduktivität von 0 und 8 dS m,1 untersucht. Die Gesamtmenge von 100 mg N l,1 im Wurzelmedium wies NH4+ -N/NO3, -N Verhältnisse von 0/100, 25/75, 50/50, 75/25 und 100/0 auf. Mischungen von NH4+ und NO3, führten zu einer größeren Aufnahme durch die Pflanzen als bei alleiniger Anwendung von NO3, oder NH4+. Die Pflanzen produzierten signifikant mehr Gesamttrockenmasse mit Mischungen der beiden N-Formen im Vergleich zu alleiniger Anwendung von NH4+ oder NO3,. Die Gesamttrockenmasse sowie die N-Gehalte von Wurzel und Sproß nahmen mit steigender Versalzung ab. Versalzungs- und N-Versorgungs-Interaktion war signifikant in allen Versuchsbedingungen. Eine signifikante positive Korrelation (r=0,97) wurde zwischen Stickstoffkonzentration und der Trockenmasseproduktion der Pflanze gefunden. [source] Competitive dynamics in two- and three-component intercropsJOURNAL OF APPLIED ECOLOGY, Issue 3 2007METTE KLINDT ANDERSEN Summary 1Intercropping is receiving increasing attention because it offers potential advantages for resource utilization, decreased inputs and increased sustainability in crop production, but our understanding of the interactions among intercropped species is still very limited. 2We grew pea Pisum sativum, barley Hordeum vulgare and rape Brassica napus as sole crops and intercrops under field conditions using a replacement design. We collected total dry matter data from sequential harvests and fitted the data to a logistic growth model. At each harvest we estimated the relative Competitive Strength (CS) of the three crops by fitting the data to a simple interspecific competition model. 3The pea monocrop produced the largest amount of biomass from the middle to the end of the growth period, but pea was not dominant in intercrops. 4Fitting data to a logistic growth model emphasizes the importance of initial size differences for interactions among intercrops. Barley was the dominant component of the intercrops largely because of its initial size advantage. The competitive effect of barley on its companion crops, measured as CS, increased throughout most of the growing season. 5The performance of each crop species was very different when it grew with a second species rather than in monoculture, but addition of a third crop species had only minor effects on behaviour of the individual crops. 6Synthesis and applications. Including sequential harvests in experiments on intercropping can provide important information about how competitive hierarchies are established and change over time. Our results suggest that increased understanding of the role of asymmetric competition among species and the resulting advantages of early germination and seedling emergence would be valuable in designing intercrops. More focus on understanding the mechanisms that govern interactions between intercropped species is needed for designing optimized intercropping systems. [source] Price relationships in the Queensland barley marketAGRIBUSINESS : AN INTERNATIONAL JOURNAL, Issue 2 2002V. Jyothi Gali Barley can be differentiated into feed and malting barley based on its end-use markets. Substitutability both in supply and in demand complicates analysis of price information in the barley market. This article examines the price linkages between feed and malting barley in the Queensland barley market using cointegration and error correction models. Malting barley prices respond to restore equilibrium relationships with corresponding feed barley prices in the long run, but not vice versa. Thus feed barley prices appear to be a leading indicator of malting barley prices. [JEL codes: L100, C22, N57.] © 2002 Wiley Periodicals, Inc. [source] The effects of organic and conventional fertilizers on cereal aphids and their natural enemiesAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2010Michael P. D. Garratt 1Aphids are important pests of spring cereals and their abundance and the impact of their natural enemies may be influenced by fertilizer regime. 2We conducted a 2-year field study investigating the effects of organic slow-release and conventional fertilizers on cereal aphids, hymenopteran parasitoids and syrphid predators and considered how the effects of fertilizers on barley morphology and colour might influence these species. 3Barley yield was greater in conventionally fertilized pots. Barley morphology was also affected by treatment: vegetative growth was greater under conventional treatments. Barley receiving organic fertilizers or no fertilizer was visually more attractive to aphids compared with plants receiving conventional fertilizers. 4Aphids were more abundant in conventionally fertilized barley but the reason for this increased abundance was species specific. Metopolophium dirhodum was responding to fertilizer effects on plant morphology, whereas Rhopalosiphum padi was sensitive to the temporal availability of nutrients. 5Syrphid eggs were more numerous in conventionally fertilized pots, whereas the response of parasitoids appeared to be dependent on the abundance of aphids, although the number of parasitoid mummies was low in both years. 6This research shows that the fertilizer treatment used can affect numerous characteristics of plant growth and colour, which can then influence higher trophic levels. This knowledge might be used to make more informed fertilizer application choices. [source] Indole-related Compounds Induce the Resistance to Rice Blast Fungus, Magnaporthe grisea in BarleyJOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2004M. Ueno Abstract When barley leaves pretreated with indole-3-acetic acid (IAA), tryptamine and tryptophan solutions at 50 ,g/ml, which did not show antifungal activity, were inoculated with Magnaporthe grisea spores 24 h after chemical pretreatments, both blast lesion and infection-hypha formations were significantly inhibited. Such resistance to M. grisea in barley was induced from 12 h after the pretreatment. In barley leaves pretreated with IAA, tryptamine and tryptophan at 50 ,g/ml, phenylalanine ammonia-lyase (PAL), peroxidase and chitinase activities were already significantly enhanced before M. grisea inoculation, when compared with that in distilled water (DW)-treated leaves as a control. In chemical-pretreated leaves, furthermore, H2O2 generation was observed by M. grisea inoculation before lesion formation, but not in DW-pretreated leaves as a control even by M. grisea inoculation. These results suggested that indole-related compounds IAA, tryptamine and tryptophan can protect barley from M. grisea as functioning as the plant activator. Studies on indole-related compounds may contribute to develop new plant activators for disease control. [source] Yield Responses of Barley to Leaf Stripe (Pyrenophora graminea) under Experimental Conditions in Southern SyriaJOURNAL OF PHYTOPATHOLOGY, Issue 8-9 2004M. I. E. Arabi Abstract The seed-borne pathogen, Pyrenophora graminea is the causal agent of barley leaf stripe disease. Field trials were undertaken to investigate the impact of leaf stripe on barley yield in two growing seasons in Southern Syria, by comparing plots with and without artificial inoculation. Ten barley cultivars originating from widely dispersed areas were used. The overall response to leaf stripe differed with the differences in susceptibility levels of the cultivars. Grain yield, the number of tillers, kernel weight and plant biomass decreased as disease severity increased. Diseased plants had fewer tillers, and as a consequence a reduced grain yield per plant. High yield losses resulted from leaf stripe in susceptible cultivars in Arrivate, Furat 1, WI2291 and Arabi Abiad with 44%, 50%, 73% and 92%, respectively. The cultivar Banteng had the best level of resistance to the disease, and is a candidate donor for resistance in future breeding programmes. As leaf stripe can dramatically reduce barley yields under favourable conditions, the disease should be considered by crop improvement programmes in Mediterranean and similar environments. [source] The effects of refined barley ,-glucan on the physico-structural properties of low-fat dairy products: curd yield, microstructure, texture and rheologyJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2004Carmen M Tudorica Abstract The beneficial role of dietary fibre in human nutrition has lead to a growing demand for incorporation of novel fibres, particularly barley ,-glucans, into foods. Barley ,-glucans are regarded as dietary fibre ingredients that are partially soluble in water. The aim of the present work was to investigate the possibility of using barley ,-glucan in milk systems in relation to the coagulation properties of milk containing ,-glucan, and to the rheology, texture and microstructure of fresh curds. The rate of coagulation and optimum coagulum cutting time were evaluated using rheological measurements. Results show that coagulation/gelation time of the milk can be reduced significantly with the incorporation of ,-glucan; curd yield increased and the viscoelastic properties of the curd were altered with ,-glucan additions. The relationships between curd rheological behaviour and its microstructure are discussed in relation to use of novel hydrocolloids in dairy processing. The results suggest that barley ,-glucan has the potential to be used as a fat replacer in low-fat dairy systems. Copyright © 2004 Society of Chemical Industry [source] A proteomic analysis of 14-3-3 binding proteins from developing barley grainsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 6 2006Ross D. Alexander Abstract 14-3-3 proteins are important eukaryotic regulatory proteins. Barley (Hordeum vulgare,L.) 14-3-3A was over-expressed, immobilised and used to affinity purify 14-3-3 binding proteins from developing barley grains. Binding was shown to be phosphorylation-dependent. These proteins were fractionated by PAGE and identified by MALDI-TOF MS. In total, 54,14-3-3 binding proteins were identified, 49,of these interactions are novel to plants. These proteins fell into a number of functional categories. The largest category was for carbohydrate metabolism, including plastidic enzymes for starch synthesis and modification. 14-3-3 was shown to be present in isolated plastids. Four of five enzymes involved in sucrose biosynthesis from triose phosphates were identified, suggesting co-ordinated regulation of this pathway. Invertase and sucrose synthase, which break down sucrose to hexoses, were found. Sucrose synthase activity was shown to be inhibited by exogenous 14-3-3 in a dosage-dependent manner. The second-largest functional group was for proteins involved in stress and defence responses; for example, RGH2A, closely related to the MLA powdery mildew resistance protein, was found. This work illustrates the broad range of processes in which 14-3-3 may be involved, and augments previous data demonstrating key roles in carbohydrate metabolism and plant defence. [source] Cropping patterns in the Canadian Prairies: thirty years of changeTHE GEOGRAPHICAL JOURNAL, Issue 2 2002William J. Carlyle Changes in cropping patterns in the Canadian Prairies are examined from the early 1960s to the mid-1990s using census data. Patterns of change within the region are mapped by census division using averaged proportions of land in crops occupied by the main crops for three pairs of census years. Spring wheat and oat have undergone the most significant relative declines. Canola increased dramatically from being the sixth-ranked crop by area in the early 1960s to the third-ranked crop by area by the 1990s. The main change in the Brown soil zone has been a large decline in spring wheat and a compensatory gain in durum wheat. Increases in special crops, especially pulse crops, canola and durum wheat have offset a substantial decline in spring wheat in the Dark Brown soil zone. Barley, tame hay and especially canola have increased at the expense of spring wheat, oat and flaxseed in the Black and Gray soil zones. Prices, transportation costs, changing export markets, crop breeding and local processing all have contributed to these changes. [source] Different Patterns of Physiological and Molecular Response to Drought in Seedlings of Malt- and Feed-type Barleys (Hordeum vulgare)JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 1 2010M. Rapacz Abstract A number of physiological and molecular characteristics are proposed as selection criteria for drought tolerance. This study measured the associations between physiological and molecular characteristics of drought response in malting and fodder spring barleys. Plants of 13 malt- and 14 feed-type Polish genotypes were exposed to drought at the four-leaf stage for 7 days. Drought susceptibility indexes (DSI) were calculated for membrane integrity, water status, gas exchange and PSII photochemical activity. Accumulation of HVA1 and SRG6 transcripts in drought was measured with real-time PCR. A wide range of variation in the drought response was observed among studied genotypes. Malting barleys were less sensitive to drought than feed-barleys according to all the traits studied. In both groups, different patterns of relationships between traits were observed. In malting genotypes only, CO2 assimilation rates in drought, as well as PSII efficiency were related to both water content and the accumulation of HVA1 transcript in leaves. On the other hand the SRG6 expression was highly correlated in both groups of barley with the photochemical efficiency of PSII. The results suggest that different physiological, biochemical and molecular characteristics should be applied in the selection towards drought resistance in the case of malting and fodder barleys. [source] Feeding the colleges: Cambridge's food and fuel supplies, 1450,1560ECONOMIC HISTORY REVIEW, Issue 2 2003John S. Lee Summary Von Thünen's model of the relationship between concentrated urban demand and rural land use proposes that towns will draw agricultural produce from a series of zones of specialized production around the urban centre. Using the accounts of King's Hall and King's College, this article identifies the areas that supplied Cambridge with food and fuel during the fifteenth and sixteenth centuries, and the persistence of such trade. Local geographical conditions meant that, contrary to von Thünen's model, firewood and charcoal were brought from more distant regions than those supplying wheat and malt barley, and Cambridge's hinterland also had to compete with demand from London. [source] Identification of hydroxyl copper toxicity to barley (Hordeum vulgare) root elongation in solution cultureENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2009Xuedong Wang Abstract The effect of pH on the acute toxicity of Cu to barley (Hordeum vulgare) root elongation was investigated in solution culture. The results showed that the median effective concentrations (EC50s; i.e., the concentration that reduced root elongation by 50% based on free Cu2+ activity) were not significantly different in the low-pH range from 4.5 to 6.5, but in the high-pH range from 7.0 to 8.0, a significant effect of pH on EC50s was found. The nonlinear relationship between EC50 and H+ activity in the present study indicated that the increased toxicity with increasing pH in solution may not be caused by decreasing H+ competition. When we take account of CuOH+ activities, a good linear relationship (r2 > 0.97) between the ratio of CuOH+ activity to free Cu2+ activity and acute Cu toxicity to barley root elongation was achieved, which indicated that the observed toxicity in the high-pH range may be caused by CuOH+ plus free Cu2+ in solution. Linear-regression analysis suggested CuOH+ had a greater binding affinity than Cu2+ at the biotic ligand sites. The logistic dose,response curve showed that expressing the Cu dose as Cu2+ + 2.92·CuOH+ improved the data fit significantly compared to consideration of the free Cu2+ activity only. Thus, our results suggest CuOH+ was highly toxic to barley root elongation. The enhanced toxicity of CuOH+ therefore needs to be considered when modeling the effect of pH on Cu toxicity to barley for exposures having pH greater than 6.5. [source] Localized lesions of arcopallium intermedium of the lateral forebrain caused a handling-cost aversion in the domestic chick performing a binary choice taskEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2006Naoya Aoki Abstract Behavioral effects of handling cost (time and/or energetic cost for food consumption) on choice were examined using domestic chicks trained in operant task reinforced by delayed food rewards. When scattered sesame was delivered in more demanding conditions, a colored cue bead associated with six grains (,large' and ,costly' reward) was chosen progressively less frequently against another bead associated with one grain (,small' and ,not costly' reward). The choice thus proved to be highly sensitive to the anticipated handling cost. Excitotoxic lesion of the bilateral arcopallium intermedium also selectively reduced the choice of the six grains, while leaving actual cost investment (number of pecks and handling time) unaltered. No significant changes occurred in choices between one grain of sesame (,small' and ,not costly' reward) and one grain of barley (or a ball composed of six sesame grains glued by starch; ,large' and ,not costly' reward), indicating that choice based on anticipated food amount was not impaired. On the other hand, lesion of the ventral striatum did not change the choice ratio in any trial types. Operant peck latencies somewhat depended on food rewards, but were not affected by lesions of the arcopallium or the ventral striatum. The arcopallium could contribute to foraging behaviors by enabling chicks to overcome the handling cost, thus gaining more beneficial food. Furthermore, the present results indicate doubly dissociated functional roles of the ventral striatum and the arcopallium, the former in the cost of traveling for food and the latter in the cost of handling food, respectively. [source] RAPID SPECIATION FOLLOWING RECENT HOST SHIFTS IN THE PLANT PATHOGENIC FUNGUS RHYNCHOSPORIUMEVOLUTION, Issue 6 2008Pascal L. Zaffarano Agriculture played a significant role in increasing the number of pathogen species and in expanding their geographic range during the last 10,000 years. We tested the hypothesis that a fungal pathogen of cereals and grasses emerged at the time of domestication of cereals in the Fertile Crescent and subsequently speciated after adaptation to its hosts. Rhynchosporium secalis, originally described from rye, causes an important disease on barley called scald, although it also infects other species of Hordeum and Agropyron. Phylogenetic analyses based on four DNA sequence loci identified three host-associated lineages that were confirmed by cross-pathogenicity tests. Bayesian analyses of divergence time suggested that the three lineages emerged between ,1200 to 3600 years before present (B.P.) with a 95% highest posterior density ranging from 100 to 12,000 years B.P. depending on the implemented clock models. The coalescent inference of demographic history revealed a very recent population expansion for all three pathogens. We propose that Rhynchosporium on barley, rye, and Agropyron host species represent three cryptic pathogen species that underwent independent evolution and ecological divergence by host-specialization. We postulate that the recent emergence of these pathogens followed host shifts. The subsequent population expansions followed the expansion of the cultivated host populations and accompanying expansion of the weedy Agropyron spp. found in fields of cultivated cereals. Hence, agriculture played a major role in the emergence of the scald diseases, the adaptation of the pathogens to new hosts and their worldwide dissemination. [source] Identification of the N-termini of NADPH : protochlorophyllide oxidoreductase A and B from barley etioplasts (Hordeum vulgare L.)FEBS JOURNAL, Issue 4 2009Matthias Plöscher The N-termini of the NADPH : protochlorophyllide oxidoreductase (POR) proteins A and B from barley and POR from pea were determined by acetylation of the proteins and selective isolation of the N-terminal peptides for mass spectrometry de novo sequence analysis. We show that the cleavage sites between the transit peptides and the three mature POR proteins are homologous. The N-terminus in PORA is V48, that in PORB is A61, and that in POR from pea is E64. For the PORB protein, two additional N-termini were identified as A62 and A63, with decreased signal intensity of the corresponding N-terminal peptides. The results show that the transit peptide of PORA is considerably shorter than previously reported and predicted by ChloroP. A pentapeptide motif that has been characterized as responsible for binding of protochlorophyllide to the transit peptide of PORA [Reinbothe C, Pollmann S, Phetsarath-Faure P, Quigley F, Weisbeek P & Reinbothe S (2008) Plant Physiol148, 694,703] is shown here to be part of the mature PORA protein. [source] Structural analysis of photosystem II in far-red-light-adapted thylakoid membranesFEBS JOURNAL, Issue 1 2000New crystal forms provide evidence for a dynamic reorganization of light-harvesting antennae subunits We studied two-dimensional crystals of the major pigment,protein complex, photosystem II, in far-red-light-adapted thylakoid membranes of the viridis-zb63 mutant of barley. Significantly larger grana membranes were produced with an increased synthesis of the entire photosystem II complex. These red-light-adapted membranes also contained two-dimensional crystals with a high frequency. Three different crystal forms of photosystem II were observed, providing the following data which further our understanding of the architecture of the native complex. (a) The oligomeric form of photosystem II in the membrane was monomeric in all crystal forms, but with a clear non-crystallographic pseudo-twofold symmetry. This was more apparent on the lumenal face of the complex. (b) The variability of unit cell contacts in different crystal forms implied that the peripheral light-harvesting antenna complex and the core of the complex were loosely connected. These peripheral subunits were predicted to rearrange so that they can either encircle the core complex or associate in parallel channels separated by lines of core complexes. (c) Grana membranes were found to retain a double-layered inside-out character, with a stromal face-to-stromal face packing. However, the presence of a crystal in one membrane did not necessarily impose crystallinity on its pair. [source] Effects of genotype, location and baking on the phenolic content and some antioxidant properties of cereal speciesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2010Valeria Menga Summary In order to assess the effect of genotype, location and their interaction on total phenolic content (TPC) of chemical extracts, the whole grains of durum and soft wheat, oat, barley and triticale were evaluated. Data showed differences in phenolic content of chemical extracts among cereal species and the analysis of variance confirmed the key role of location. Besides TPC and trolox equivalent antioxidant capacity (TEAC) values assessed by chemical extraction were compared with those obtained with an in vitro digestive enzymatic extraction. Differences were found between methanolic and enzymatic extracts, and data confirmed that enzymatic technique enhanced extraction of antioxidants but pointed out lesser differences among cereal types. The breads obtained by flours enriched with different levels of bran were also evaluated. Chemical extracts highlighted the increasing levels of antioxidants according to bran enrichments, without pointing out changes caused by baking. The enzymatic extraction instead did not show differences regarding to bran enrichments, but documented a loss in antioxidant properties of breads in respect to corresponding flours. On the other hand the scarce differences between flours and corresponding breads did not allow asserting that baking modified the TPC and TEAC, independently of the extraction methods used. Indeed, during baking process, also the observed phenolic acids profile variations did not vary the antioxidant properties of breads. [source] Kavut, a traditional Turkish cereal product: production method and some chemical and sensorial propertiesINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2006Mehmet Murat Karao Summary Kavut is a cereal-based product made from wholemeal wheat and barley flour, milk or milk powder, fat and sugar. In this study, the best processing method and formulation were investigated by analysing different formulations and processing methods for the kavut. Four different flour combinations (100% wheat without barley, 75% wheat + 25% barley, 50% wheat + 50% barley, 25% wheat + 75% barley), two shortening (butter and margarine) and three different roasting periods (1, 1.5, 2 min) at 250 °C were used in the study. Significant changes were observed in the physical and chemical properties of the cereal by heat treatment in the kavut production. Increase of barley flour in the mixture decreased protein content, softness, altered L colour values, appearance, texture, mouth-feel, and general acceptance and increased ash content, +a and the absorbance value of kavut. While the longer roasting period resulted in reduced softness and colour (L-value) of kavut, roasting period did not significantly affect the general acceptance of kavut. Kavut made from only whole wheatflour was most preferred by the panellists. [source] Fluorescence polarization immunoassay based on a monoclonal antibody for the detection of ochratoxin AINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2004Won-Bo Shim Summary A fluorescence polarization immunoassay (FPIA) based on a monoclonal antibody for the determination of ochratoxin A (OTA) was developed. Fluorescein-labelled OTA derivative (tracer) was synthesized and purified by thin-layer chromatography. The optimized OTA FPIA had a dynamic range from 5 to 200 ng mL,1 with IC50 value of 30 ng mL,1 and a detection limit of 3 ng mL,1. The method developed was characterized by high specificity and reproducibility. Cross-reactivity with other mycotoxins (zearalenone, aflatoxins, patulin and T-2 toxin) was negligible (<0.1%). Methanol extracts of barley samples were used for the analysis. The results of OTA determination in barley were compared with those determined by indirect competitive enzyme-linked immunosorbent assay (ELISA). Recoveries for the samples spiked at 50, 100 and 500 ng g,1 levels were 91, 90 and 97%, respectively, for FPIA, and 98, 98 and 102%, for ELISA. Naturally contaminated barley samples were analysed by these methods but some disagreement was observed between the results. The FPIA method can be applied for screening of food samples for OTA residues without a complicated clean-up. [source] Upscaling water savings from farm to irrigation system level using GIS-based agro-hydrological modelling,IRRIGATION AND DRAINAGE, Issue 1 2007Shahbaz Khan simulation d'irrigation; extrapolation; efficacité d'utilisation de l'eau; économie de l'eau Abstract Irrigation continues to be the main water user on a global scale despite the increase in water use by sectors other than agriculture. More efficient water application technologies and water management practices are ways of realising potential water savings, thus moderating the negative impacts of higher water use on farm incomes and environmental impact on rivers and groundwater systems. This paper describes an integrated approach of agro-hydrological modelling for determining potential water savings achievable by adopting high-tech irrigation technologies at farm level and application of GIS techniques to upscale those benefits at the regional irrigation system level. The SWAP (Soil,Water,Atmosphere,Plant) model was used for the simulation of water use at the farm level. The results are promising, as the potential water saving ranges from 0.1 to 2.2,ML,ha,1 (10,220,mm) for different broad-acre crops, 1.0 to 2.0,ML,ha,1 (100,200,mm) in sprinkler and 2.0 to 3.0,ML,ha,1 (200,300,mm) in drip irrigation for citrus, 1.0 to 1.5,ML,ha,1 (100,150,mm) in sprinkler and up to 4.0,ML,ha,1 (400,mm) in drip irrigation for vineyards and 0.5 to 1.0,ML,ha,1 for vegetables (50,100,mm). SWAP simulations show crop water saving potential of 7% for maize, 15% for soybean, 17% for wheat, 35% for barley, 17% for sunflower and 38% for fababean from the current water use statistics in Australia. Spatial analysis in GIS environment is carried out to investigate the spatial variations of water use for a particular crop under different depths to water table and varying soil types. Maps of water need for all broad-acre crops are drawn and pixel-to-pixel comparison is performed to determine the water saving potential per unit area. The upscaling approach shows that considerable water amounts could be saved both in Murrumbidgee Irrigation Area (MIA) and Coleambally Irrigation Area (CIA) with potential water saving of 36 to 95,GL (MCM) in MIA and 42 to 72,GL (MCM) in CIA. Copyright © 2007 John Wiley & Sons, Ltd. L'irrigation reste l'usage principal de l'eau à l'échelle mondiale en dépit de l'augmentation des volumes utilisés par les secteurs autres que l'agriculture. L'amélioration des techniques d'irrigation et des procédures de gestion de l'eau permet de réaliser des économies d'eau potentielles, modérant ainsi les impacts négatifs d'une surconsommation d'eau sur les revenus agricoles et ses incidences sur l'environnement des cours d'eau et des aquifères. Cet article décrit comment un modèle agro-hydrologique intégré peut déterminer les économies d'eau réalisables grâce à l'adoption de technologies de pointe dans l'irrigation au niveau de l'exploitation agricole et à l'application des techniques de SIG à l'extension de ces avantages au niveau d'un système régional d'irrigation. Le modèle SWAP (Sol-Eau-Atmosphère-Plante) a été employé pour simuler l'utilisation de l'eau au niveau de l'exploitation. Les résultats sont prometteurs car l'économie d'eau potentielle va de 100 à 2 200 m3/ha (10 à 220 millimètres) pour différentes cultures de plein champ, de 1 000 à 2 000 m3/ha (100 à 200 millimètres) en aspersion et de 2 000 à 3 000 m3/ha (200 à 300 millimètres) en goutte à goutte sur des citronniers, de 1 000 à 1 500 m3/ha (100 à 150 millimètres) en aspersion et jusqu'à 4 000 m3/ha (400 millimètres) en goutte à goutte sur de la vigne, et de 500 à 1 000 m3/ha pour des légumes (50 à 100 millimètres). Les simulations de SWAP à partir de données statistiques australiennes courantes montrent un potentiel d'économie d'eau de 7% pour le maïs, 15% pour le soja, 17% pour le blé, 35% pour l'orge, 17% pour le tournesol et 38% pour les fèves. Une analyse par SIG permet d'étudier les variations spatiales de l'utilisation de l'eau pour une récolte particulière selon la profondeur de la nappe et le type de sol. Les besoins en eau de toutes les cultures de plein champ sont cartographiés et le potentiel d'économie d'eau par unité de surface est estimé pixel par pixel. L'extrapolation des résultats montre que des volumes d'eau considérables pourraient être économisés dans les zones irriguées de Murrumbidgee (MIA, économie potentielle de 36 à 95 millions de m3) et de Coleambally (CIA, économie potentielle de 42 à 72 m3). Copyright © 2007 John Wiley & Sons, Ltd. [source] Linear and non-linear optimization models for allocation of a limited water supply,IRRIGATION AND DRAINAGE, Issue 1 2004Bijan Ghahraman optimisation de l'irrigation; déficit d'irrigation; Iran Abstract One partial solution to the problem of ever-increasing demands on our water resources is optimal allocation of available water. A non-linear programming (NLP) optimization model with an integrated soil water balance was developed. This model is the advanced form of a previously developed one in which soil water balance was not included. The model also has the advantage of low computer run-time, as compared to commonly used dynamic programming (DP) models that suffer from dimensionality. The model can perform over different crop growth stages while taking into account an irrigation time interval in each stage. Therefore, the results are directly applicable to real-world conditions. However, the time trend of actual evapotranspiration (AET) for individual time intervals fluctuates more than that for growth-stage AETs. The proposed model was run for the Ardak area (45,km NW of the city of Mashhad, Iran) under a single cropping cultivation (corn) as well as a multiple cropping pattern (wheat, barley, corn, and sugar beet). The water balance equation was manipulated with net applied irrigation water to overcome the difficulty encountered with incorrect deep percolation. The outputs of the model, under the imposed seasonal irrigation water shortages, were compared with the results obtained from a simple NLP model. The differences between these two models (simple and integrated) became more significant as irrigation water shortage increased. Oversimplified assumptions in the previous simple model were the main causes of these differences. Copyright © 2004 John Wiley & Sons, Ltd. L'allocation optimale des ressources d'eau disponibles est une réponse partielle au problème de la demande sans cesse croissante de consommation d'eau. Un modèle d'optimisation à programmation non linéaire (NLP) qui intègre un bilan hydrique a été développé. Ce modèle est une version avancée d'un modéle précédent qui n'intégrait pas ce bilan hydrique. Il présente l'avantage de nécessiter moins de puissance informatique en comparaison des modèles à programmation dynamique (DP) généralement utilisés. Le modèle peut s'appliquer à différentes étapes de la croissance des cultures et prend en compte des fréquences d'irrigation variables. Ainsi, les résultats sont directement applicables aux conditions réelles. Le modèle proposé a été utilisé sur une seule culture (maïs) dans la région d'Ardak à 45,km nord-ouest de Mashad, Iran, et sur de multiples cultures (blé, orge, maïs, betterave sucrière). L'équation de bilan hydrique a été calibrée pour maîtriser les difficultés rencontrées avec des mesures d'infiltration incorrectes. Les résultats du modèle, dans le cadre de restrictions d'irrigation saisonnière imposées, ont été comparés avec ceux obtenus par un modèle simple NLP. Les différences entre ces deux modèles (simple et intégré) deviennent plus significatives à mesure que les restrictions d'irrigation augmentent. Les hypothèses trop simplistes du modèle simple sont la cause de ces différences. Copyright © 2004 John Wiley & Sons, Ltd. [source] Optimal Hedging Ratios for Wheat and Barley at the LIFFE: A GARCH ApproachJOURNAL OF AGRICULTURAL ECONOMICS, Issue 2 2000P. J. Dawson Over 100,000 futures contracts for cereals are traded annually on the London International Financial Futures Exchange. The proportion of the spot position held as futures contracts - the hedging ratio - is critical to traders and traditional estimates, using OLS, are constant over time. In this paper, we estimate time-varying hedging ratios for wheat and barley contracts using a multivariate generalised autoregressive conditional heteroscedasticity (GARCH) model. Results indicate that GARCH hedging ratios do change through time. Moreover, risk using the GARCH hedge is reduced significantly by around 4 per cent for wheat and 2 per cent for barley relative to the no hedge position, and significantly by around 0.2 per cent relative to the constant hedge. The optimal, expected utility-maximising, and the risk-minimising hedging ratios are equivalent. [source] | |||||||||||||||||||||||||||||||||||||