Wheat Cultivation Areas Research Articles

Mycotoxin profile of Fusarium langsethiae isolated from wheat in Italy: production of type‐A trichothecenes and relevant glucosyl derivatives

Fusarium langsethiae, formally described as a new species over a decade ago, has been identified as the main producer of HT-2 (HT2) and T-2 (T2) toxins in Europe in small cereal grains. Mycotoxin contamination caused by this Fusarium species can represent a food safety hazard that deserves further attention. In the present work, the mycotoxin profile in wheat cultures of F. langsethiae is presented with particular reference to the production of major type-A trichothecenes and their glucosyl derivatives. F. langsethiae isolates, representative of the major Italian wheat cultivation areas, were tested for the production of T2, HT2, diacetoxyscirpenol (DAS) and neosolaniol (NEO), and relevant glucosyl derivatives. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used for the identification and chemical characterization of these metabolites. F. langsethiae isolates under investigation resulted to be potent producers of T2, HT2 and NEO. Furthermore, a well-defined set of isolates, all originating from Central Italy, produced also DAS. All isolates were found to be able to produce HT2 glucosyl derivatives, whereas only traces of T2 glucoside were detected in one sample. Furthermore, two mono-glucosyl derivatives of NEO and one mono-glucoside derivative of DAS were identified and characterized. The screening for the presence/absence of glucosylated trichothecenes in analyzed fungal extracts revealed a general co-occurrence of these derivatives with the parent toxin at levels that could be roughly estimated to account up to 37% of the relevant unconjugated toxin. This is the first report of the production of glucosylated trichothecenes by F. langsethiae cultured on small grains.

Assessment of Land Suitability Potentials for Selecting Winter Wheat Cultivation Areas in Beijing, China, Using RS and GIS

It is very important to provide reference basis for winter wheat quality regionalization of cultivation area. The aim of this article was based on factors affecting wheat quality and setting realistic spatial models in each part of the land for assessment of land suitability potentials in Beijing, China. The study employed artificial neural network (ANN) analysis to select factors and evaluate the relative importance of selected environment factors on wheat grain quality. The spatial models were developed and demonstrated their use in selecting the most suitable areas for the winter wheat cultivation. The strategy overcomes the non-accurate traditional statistical methods. Satellite images, toposheet, and ancillary data of the study area were used to find tillable land. These categories were formed by integrating the various layers with corresponding weights in geographical information system (GIS). An integrated land suitability potential (LSP) index was computed considering the contribution of various parameters of land suitability. The study demonstrated that the tillable land could be categorized into spatially distributed agriculture potential zones based on soil nutrient and assembled weather factors using RS and GIS as not suitable, marginally suitable, moderately suitable, suitable, and highly suitable by adopting the logical criteria. The sort of land distribution map made by the factors with their weights showed more truthfulness.

Fungal diversity and natural occurrence of fusaproliferin, beauvericin, deoxynivalenol and nivalenol in wheat cultivated in Santa Fe Province, Argentina

The Fusarium diversity and the mycobiota associated with moldy wheat kernels from Santa Fe province, Argentine, was assessed. The wheat cultivated area in Santa Fe province is divided according to agrometeorological conditions into two zones: Zone I (north-central) and Zone II (south). The natural occurrence of Fusarium toxins BEA, FUP, DON and NIV was also determined. Cladosporium was the most abundant of the 19 genera identified, followed by Fusarium, Phoma and Alternaria. Zone II shows a predominance of F. graminearum and F. culmorum. In Zone I, DON was present in 13/32 samples (range 0.43-3.60mgkg(-1)) and NIV in 6/32 samples (range 0.11-0.40mgkg(-1)). In zone II, DON was found in 11/21 samples (range 0.57-9.50mgkg(-1)) and NIV in 4/21 samples (range 0.10-0.60mgkg(-1)). BEA and FP were not detected in both zones.

Design of fuzzy logic control system incorporating human expert knowledge for combine harvester

Many factors affect the yield loss in wheat harvesting with a grain combine harvester. Grain harvesting is a non-linear process, is of considerable complexity, and there is no mathematical model to describe the behavior of this complex system. In this paper, a fuzzy logic controller (FLC) incorporating human expert knowledge is designed for automatic adjustment and control of the harvester to achieve minimal grain losses especially at the position of straw walker and upper sieve. The FLC automatically adjusts cylinder speed, concave clearance, fan speed and forward speed of the combine based on the measured losses at straw walker and sieve sections. The designed FLC expert system consists two inputs and four outputs. Trapezoidal membership functions were selected for input fuzzy linguistic variables (straw walker and sieve losses), whereas fuzzy singletons were considered for the outputs. Based on human expert knowledge, six rules with logical AND operator and Mamdani implication are extracted. FLC was implemented in a programmable logic controller (PLC). Field experiments in two different irrigated or non-irrigated cultivated areas in order to evaluate the system. It was found the losses at the position of straw walker and upper sieve in the irrigated wheat cultivated area is much higher than the dry wheat cultivation area. Statistical analysis using t-test was also indicated a significant difference ( p < 1%) between loss mean in the combine equipped with the controller and the one without FLC.

Genetic differentiation of hexaploid wheat inferred from analysis of microsatellite loci

Landraces of wheat can serve as important potential sources for extending the genetic basis of selection cultivars. Analysis of microsatellites and typing of polymorphism in a representative sample of 347 genotypes, including landraces and selection cultivars, was performed using a set of 38 selected oligonucleotide primer pairs. Classification of genotypes with respect to the level of their similarity was performed using cluster analysis. The data obtained pointed to genetic differentiation of hexaploid wheat. The groups of cultivars, the formation of which was thought to be associated with the main old areas of wheat cultivation in Europe and Asia, were identified. The basis of each of the groups was formed by landraces of common wheat. The differences between the groups identified were associated with multiple changes in the wheat genome and were expressed as quantitative differences in the allele frequencies of microsatellite loci. The results of the study are of interest in terms of understanding the structure of wheat genetic diversity and revealing the pathways of evolution of this culture.

Relationships between rainfall characteristics and ephemeral gully erosion in a cultivated catchment in Sicily (Italy)

Recent research has shown a lack of long-term monitoring for detailed analysis of gully erosion response to climate characteristics. Measures carried out from 1995 to 2007 in a wheat-cultivated area in Raddusa (Sicily, Italy), represent one of the longest series of field data on ephemeral gully, EG, erosion. The data set collected in a surface area of almost 80 ha, permits analysis of the influence of rainfall on EG formation and development. Ephemeral gullies formed in the study area were measured on a yearly scale with a Post-Processing Differential GPS for length and with a steel tape for the width and depth of transversal sections. Ephemeral gully formation was observed for 8 years out of 12, which corresponds to a return period of 1.5 years. The measurements show strong temporal variability in EG erosion, in agreement with the rainfall characteristics. The total eroded volumes ranged between 0 and ca. 800 m 3 year −1, with a mean of ca. 420 m 3 year −1, corresponding to ca. 0.6 kg m −2 year −1. Ephemeral gully erosion in the study area is directly and mainly controlled by rainfall events. An antecedent rainfall index, the maximum value of 3-days rainfall ( H max 3_d), is the rain parameter which best accounts for EG erosion. This index is used here as a simple surrogate for soil water content. An H max 3_d threshold of 51 mm was observed for EG formation. The return period of the H max 3_d threshold is almost the same as the return period for EG formation. Although a mean of seven erosive rain events were recorded in a year, EG formation and development generally occur during a single erosive event, similarly to other semiarid environments. The most critical period is that comprised between October and January, when the soil is wetter and the vegetation cover is scarce. Empirical models for EG eroded volume estimation were obtained using the data set collected at this site. A simple power-type equation is proposed to estimate the eroded volumes using H max 3_d as an independent variable. This equation shows an R 2 equal to 0.67 and a standard error of estimation of 0.79.

Morphological spike diversity of Omani wheat

Little is known about the diversity of field crops in Oman. The objective of this study therefore was to characterize wheat accessions from this country using individual spikes collected from different wheat cultivation areas. The phenotypic assessment of 15 qualitative and 17 quantitative characters showed variations among Omani wheat landraces. The standardized phenotypic diversity index (H′) was with 0.66 higher for quantitative characters than for qualitative characters (0.52) in tetraploid wheats and with 0.63 and 0.62, respectively, in hexaploid wheats. Overall, the morphological data revealed a surprisingly high diversity among landraces and showed that simple morphological characters can be used for an effective characterization of diversity in Omani wheat.

Leaf rust of spring wheat in Northern Kazakhstan and Siberia: incidence, virulence, and breeding for resistance

Northern Kazakhstan and Western Siberia of Russia represent a relatively uniform continuous area of spring wheat cultivation of ~20 million ha. Despite the dry climate, cultivation of susceptible varieties resulted in epidemics of leaf rust on average in 1 year out of 4, affecting up to 5 million ha with yield losses of up to 25–30%. The leaf rust population showed absence of virulence for genes Lr9 and Lr24 and low frequency of isolates with virulence to Lr11, Lr16, Lr18, and Lr28. The field observations indicated that genes Lr28 and Lr36 provide resistance. All the wheat cultivars are susceptible to leaf rust and only recently have several resistant lines and new varieties have been tested in trials. The current resistance breeding efforts are based on incorporation of the resistance from local and foreign sources. The breeding strategy is not based on detailed knowledge of the leaf rust population and its interaction with the host because of limited pathology and genetics research capacity. However, practical breeding efforts in combining proven resistance with adaptation traits resulted in the development of new competitive resistant germplasm. Shuttle breeding between the region and CIMMYT-Mexico to enhance resistance contributes to regional efforts.

Analytical Study of wheat Production costs Under Economic liberalization Policy

Wheat is one of the strategic food crops. The state is working hard toachieve self sufficiency from this cereal crop in order to attain food securityand to reduce the quntity imported of wheat. on the Egyptian economyEmplementing some economic liberalization policy produced changes in thestructure of production costs and returns of wheat and other agriculturalproducts.The study Aims to investigating effect of economic reform policy onsome production and economic variables for wheat crop, by investigating theeffect through comparning between two periods, the period of study aredivided two periods, the first before applying economic reform policy (1982– 1990), the second after applying that policy (1991 – 2003) the study appliedsome economtric procdures to fulfillment the objective .The results indicate that the structural changes of Egyptian economicreform. affected on the cultivated area of wheat, productivity per feddan,wheat production, total wheat revenue, total wheat costs, farm price, and netrevenue of wheat , value- added , and internal terms of trade,The study proposed the following recommendation:-1- Increasing farm prices or provision of improved seed varieties willprovide a greet incentive for wheat farmers to increase the wheatcultivated area the production of wheat.2- Activating the role of extension programs by increasing the area andnumber of the extension fields to help the adoption of new technology inwheat production.

Genetic Diversity and Relationships of Wheat Landraces from Oman Investigated with SSR Markers

Little is known about genetic diversity and geographic origin of wheat landraces from Oman, an ancient area of wheat cultivation. The objectives of this study were to investigate the genetic relationships and levels of diversity of six wheat landraces collected in Oman with a set of 30 evenly distributed SSR markers. The total gene diversity, (HT), conserved in the three durum wheat (Triticum durum desf.) landraces (HT = 0.46) was higher than in the three bread wheat (Triticum aestivum L.) landraces (HT = 0.37), which were similar to Turkish and Mexican bread wheat landraces calculated in previous studies. Genetic variation partitioning (GST) showed that variation was mainly distributed within rather than among the durum (GST = 0.30) and bread wheat (GST = 0.19) landraces. Based on modified Rogers’ distance (MRD), the durum and bread wheat landraces were distinct from each other except for a few individuals according to principal coordinate analysis (PCoA). One bread wheat landrace (Greda) was separated into two distinct sub-populations. A joint cluster analysis with other landraces of worldwide origin revealed that Omani bread wheat landraces were different from other landraces. However, two landraces from Pakistan were grouped somewhat closer to Omani landraces indicating a possible, previously unknown relationship. Implications of these results for future wheat landrace collection, evaluation and conservation are discussed.

Heat stress in relation to protein redox status and quality traits of durum wheat

In this study elevated temperature effects on protein quality parameters and in particular on protein sulfhydryl-disulfide contents were assessed. Four Italian durum wheat cultivars which differed for the qualitative trait changes produced by heat stress were employed. During grain filling two different thermal regimes were imposed on the plants grown in a typical area of durum wheat cultivation (Southern Italy). Results confirmed significant effects of high temperatures on the quality of products in the durum wheat chain and indicated that elevated temperatures determined changes on protein redox status, particularly evident on S-S bond content. For most of the examined traits significant cultivar x treatment interactions were also evidenced.

The impact of cropland cover on river nutrient levels in the Mississippi River Basin

ABSTRACTAim This study developed high‐resolution datasets of the area of maize, soybean and wheat cultivation in the United States for 1950, 1970 and 1992. The datasets were used to examine the relationship between individual crop cover and nutrient levels in rivers across the Mississippi River Basin.Location This study was conducted in the United States, with focus on the Mississippi River Basin.Methods County and state‐level estimates of the planted area of maize, soybean and wheat were integrated with a satellite‐derived pattern in total cropland to develop 5′ × 5′ resolution datasets of the fractional area of maize, soybean and wheat in the United States for 1950, 1970 and 1992. Regression analysis was used to determine the relationships between mean levels of nitrogen, phosphorous and silica in 25 rivers across the Mississippi Basin, and the extent of maize, soybean and wheat cultivation in the watersheds.Results The crop datasets provide a spatially explicit representation of the area of the three primary crops in 1950, 1970 and 1992. The datasets clearly depict the rapid expansion of soybean cultivation, the increased specialization of individual agricultural regions, and the accompanying reduction in agricultural biodiversity since 1950. The statistical analysis identified strong correlations between the extent of maize and soybean cover in a watershed and the level of nitrogen (N) and phosphorous (P) at the watershed outlet. In particular, the area of maize appears to be strongly related to the concentration of total‐N and the ratio of dissolved inorganic‐N and organic‐N at the watershed outlet.Conclusions The intensification of cultivation of the three primary crops — maize, soybean and wheat — has altered land cover and water quality across the U.S. since 1950. The high present‐day rate of fertilizer use on maize and the expansion of soybean cultivation could be largely responsible for the change in nutrient ratios in the Mississippi River since 1950.

SW—Soil and Water: Ephemeral Gully Erosion in a Wheat-cultivated Area in Sicily (Italy)

Ephemeral gully erosion is responsible for heavy damage to agricultural land and causes sedimentation and drainage network formation in most regions. Ephemeral gully length, width and depth were measured over a 5-yr period in an area of about 120 ha of heavy soils cultivated with durum wheat in Sicily (Italy) in order to quantify the soil losses and to examine, by statistical analysis, the relationships between this kind of erosion, precipitation and the characteristics of the watersheds. Ephemeral gully formation was observed for 4 yr out of five in the study area. A mean length of about 36 m ha −1 yr −1 and mean soil losses of 3·3 m 3 ha −1 yr −1 were measured. The channel depth reached a maximum value (>1 m) 3 yr out of four. In the examined soils, this kind of erosion occurs when the moisture content of the soil is high: regression analysis indicates that the soil moisture content can be expressed by the amount of precipitation for 3 days. In the observation period, the minimum 3-day rainfall which gave rise to channel formation was 51 mm; since the 51 mm return period is less than 2 yr, the risk of erosion is high. Mean depth and width, which are the channel characteristics that vary the least between the different years, seem to be controlled by the soil, crop and field characteristics, whereas the precipitation regime seems mainly to influence their number and length. Regression equations were performed to estimate ephemeral gully surface area and soil losses measuring the length alone. Length measurement by the global position system is sufficiently accurate and fast. The influence of watershed surface area and length on ephemeral gully erosion indicates that a reduction in field area and length may be an effective measure to reduce this kind of erosion.

Genetic variability to the effects of heat stress during grain filling on durum wheat quality

During the 1996/97 season twenty durum wheat cultivars were grown in Foggia, a typical area of durum wheat cultivation in Italy, in order to assess the varietal response to the effects of heat stress on characteristics affecting grain and milling quality. In the field trial high temperature stress was imposed during grain filling by covering the plots from ten days after anthesis until ripeness with PVC film tunnels, obtaining maximum temperatures about 10°C higher in the tunnels than in the open. Results evidenced that, in general, the percentage of gluten, total and insoluble proteins increased with high temperature whereas a reduction was observed for kernel and specific weight. Considerable differences among the varieties examined in the response to heat stress were observed pointing out different sensitivity levels to this environmental factor. Therefore, on the basis of the changes of insoluble protein percentage, important qualitative parameter of durum wheat, the varieties were arranged in tolerant and sensitive groups and, in relation to grain qualitative characteristics, the different performance of the two groups was also evidenced.

Effect of Heat Shock During Grain Filling on the Gluten Protein Composition of Bread Wheat

Abstract The present study was conducted to determine the role of the variation of the temperature during grain filling on the protein composition of bread wheat evaluated by SE–HPLC. Four cultivars were grown in four typical areas of wheat cultivation in Italy; at each location, four different temperature profiles were imposed during grain filling by anticipating or delaying sowing date in the South of Italy (Foggia and Catania) or by covering the plots with plastic tunnels in the North (Milano) and in Central Italy (Viterbo). Results indicated that, independently of the genotype, growth environment (location) and different temperature regimes affect quality characteristics by allowing the synthesis of a different amount of total proteins or providing a different pattern of protein fraction accumulation. In the latter case, more pronounced effects were observed during frequent episodes of daily maximum temperatures above 35°C, particularly in the plots covered with plastic tunnels during grain filling at Milano and Viterbo. At both locations, high temperatures seemed to mainly affect the composition of the polymeric fraction, particularly the formation of larger aggregates, without influencing their total amount. The relative quantity of insoluble polymeric proteins for heat stressed samples was, in fact, significantly lower than those for samples from the normal (control) and late sowings, whereas this situation was completely reversed when the relative amount of the easily soluble polymeric proteins was considered. The possible influence of temperature on the mechanism by which intermolecular disulphide bonds are formed and the effect on composition of polymeric fractions during the deposition of storage proteins are discussed.

Tissue Nitrogen as a Base for Recommendations of Additional Nitrogen to Spring Wheat in Southern Finland

Abstract Nitrogen (N) deficiency has become more common in the traditional wheat cultivation areas of southern Finland as yield potentials have increased. Based on data for the period studied (1968-88) a grain protein concentration below 11.2% in spring wheat (Triticun aestivum L.) is an indicator of N deficiency. The mean of maximum grain yield obtained was 4655 kg ha−1 when grain protein concentration exceeded 11.2%. The estimation of plant tissue N content could be an effective diagnostic tool for identifying N status in the early growth stages of spring wheat. To address the feasibility of this test, the present study was conducted in 1990-91 to determine the critical plant tissue N concentrations of three plant parts at the early double-ridge stage (Stage 2), at the stage when stigmatic branches of the carpel begin to form (Stage 7) and at pollination (Stage 10). Nitrogen was applied at rates of 0 and 110 kg N ha−1 as granular ammonium nitrate and granular slow-release-nitrogen fertilizers to establi...

Transfer of a dominant gene for resistance to eyespot disease from a wild grass to hexaploid wheat

Eyespot disease, caused by the fungus Pseudocercosporella herpotrichoides, is responsible for considerable lodging and reductions of yield in extensive areas of wheat cultivation in North and South America, Europe, New Zealand, Australia and Africa1. The level of resistance of wheat cultivars is too low, even among the less susceptible ones (that is, Cappelle Desprez and Cerco) and no genes for resistance have to date been characterized in any species. Sprague2 found a high level of resistance to this disease in the wild grass Aegilops ventricosa and several workers have attempted its transfer to cultivated wheat with only partial success3–5. We report here a major dominant gene for resistance, which has been transferred from tetraploid Ae. ventricosa (genomes DvDvMvMv) to hexaploid wheat, Triticum aestivum (AABBDD), using tetraploid wheat, Triticum turgidum (AABB), as a ‘bridge’ species.

Migration of smaller brown plant hopper into paddy fields in the wheat and barley cultivation area in lowland

Migration of smaller brown plant hopper into paddy fields in the wheat and barley cultivation area in lowland