Functional and Nutritional Characteristics of Wheat Grown in Organic and Conventional Cropping Systems

The effects of organic versus conventional farming practices on wheat functional and nutritional characteristics were compared. Soft white winter wheat and hard red spring wheat were obtained from multiyear replicated field plots near Pullman, Washington, and Bozeman, Montana. Test weight, kernel weight, and kernel diameter tended to be greater in both soft and hard organic wheat than in conventional wheat in the Pullman studies. Phenolic content and total antioxidant capacity tended to be lower in organic than in conventional wheat. Flour ash, P, and Mg contents in whole wheat flour varied in parallel among cropping systems, but levels were not consistently associated with either organic or conventional cropping systems. Protein contents of whole wheat and refined flours were similar in organic and conventional wheat from Pullman when fertility levels were similar. Higher fertility was associated with higher protein content in both organic and conventional cropping systems. Soft wheat flour from a low‐fertility organic cropping system had lower sodium carbonate, lactic acid, and sucrose solvent retention capacities, lower protein content, and greater cookie diameter and cake volume than soft wheat flour from the higher fertility organic and conventional cropping systems; the change in end‐product quality was significant in one out of two crop years. In the Bozeman hard wheat studies, higher fertility in both organic and conventional cropping systems tended to increase protein content and bread loaf volume. Results indicated that neither organic nor conventional cropping systems were associated with substantially improved mineral and antioxidant nutritional properties, and end‐use quality of wheat was more strongly associated with fertility level than with organic versus conventional cropping systems.     

Carbon Depletion by Plowing and its Restoration by No‐Till Cropping Systems in Oxisols of Subtropical and Tropical Agro‐Ecoregions in Brazil

The continuous use of plowing for grain production has been the principal cause of soil degradation. This project was formulated on the hypothesis that the intensification of cropping systems by increasing biomass‐C input and its biodiversity under no‐till (NT) drives soil restoration of degraded agro‐ecosystem. The present study conducted at subtropical [Ponta Grossa (PG) site] and tropical regions [Lucas do Rio Verde, MT (LRV) site] in Brazil aimed to (i) assess the impact of the continuous plow‐based conventional tillage (CT) on soil organic carbon (SOC) stock vis‐à‐vis native vegetation (NV) as baseline; (ii) compare SOC balance among CT, NT cropping systems, and NV; and (iii) evaluate the redistribution of SOC stock in soil profile in relation to soil resilience. The continuous CT decreased the SOC stock by 0·58 and 0·67 Mg C ha⁻¹ y⁻¹ in the 0‐ to 20‐cm depth at the PG and LRV sites, respectively, and the rate of SOC sequestration was 0·59 for the PG site and ranged from 0·48 to 1·30 Mg C ha⁻¹ y⁻¹ for the LRV site. The fraction of C input by crop residues converted into SOC stock was ~14·2% at the PG site and ~20·5% at the LRV site. The SOC resilience index ranged from 0·29 to 0·79, and it increased with the increase in the C input among the NT systems and the SOC sequestration rates at the LRV site. These data support the hypothesis that NT cropping systems with high C input have a large potential to reverse the process of soil degradation and SOC decline. Copyright © 2013 John Wiley & Sons, Ltd.     

Mulching Affects Soil Properties and Greenhouse Gas Emissions Under Long‐Term No‐Till and Plough‐Till Systems in Alfisol of Central Ohio

Agricultural activities emit greenhouse gases (GHGs) and contribute to global warming. Intensive plough tillage (PT), use of agricultural chemicals and the burning of crop residues are major farm activities emitting GHGs. Intensive PT also degrades soil properties by reducing soil organic carbon (SOC) pool. In this scenario, adoption of no‐till (NT) systems offers a pragmatic option to improve soil properties and reduce GHG emission. We evaluated the impacts of tillage systems (NT and PT) and wheat residue mulch on soil properties and GHG emission. This experiment was started in 1989 on a Crosby silt loam soil at Waterman Farm, The Ohio State University, Columbus, Ohio, USA. Mulching reduced soil bulk density and improved total soil porosity. More total carbon (16.16 g kg⁻¹), SOC (8.36 mg L⁻¹) and soil microbial biomass carbon (152 µg g⁻¹) were recorded in soil under NT than PT. Mulch application also decreased soil temperature (0–5 cm) and penetration resistance (0–60 cm). Adoption of long‐term NT reduced the GHG emission. Average fluxes of GHGs under NT were 1.84 g CO₂‐C m⁻² day⁻¹ for carbon dioxide, 0.07 mg CH₄‐C m⁻² day⁻¹ for methane and 0.73 mg N₂O‐N m⁻² day⁻¹ for nitrous oxide compared with 2.05 g CO₂‐C m⁻² day⁻¹, 0.74 mg CH₄‐C m⁻² day⁻¹ and 1.41 mg N₂O‐N m⁻² day⁻¹, respectively, for PT. Emission of nitrous oxide was substantially increased by mulch application. In conclusion, long‐term NT reduced the GHG emission by improving the soil properties. Copyright © 2016 John Wiley & Sons, Ltd.     

Nutritional Profile of Whole‐Grain Soft Wheat Flour

Whole‐grain wheat flour is used in baking to increase fiber content and to provide vitamins from the bran layers of the kernel. We surveyed whole‐grain soft flour samples from North America to determine the nutritional profile using recently revised fiber quantification protocols, Codex 2009.1. Standard compositional and vitamin analyses were also included in the survey. Three separate studies were included in the survey: sampling of commercial whole‐grain soft wheat flour, a controlled study of two cultivars across three years and two locations, and a regional study of soft white and soft red grain from commercial grain production. The Codex method for fiber measurement estimated total fiber concentration in the commercial sampling at 15.1 g/100 g, dry weight basis (dwb). In the controlled research trial, the largest source of variation in total fiber concentration was attributed to year effects, followed by genotype effects. For the two locations used in this study, location effects on fiber concentration were significant but an order of magnitude less important than the year and genotype effects. The third study of regional variation within North America found limited variation for total fiber, with the resistant oligosaccharide fraction having the greatest variation in concentration. When all three studies were combined into a meta‐analysis, the average total fiber concentration was 14.8 g/100 g dwb. In the meta‐analysis, concentrations of folate, thiamin, riboflavin, niacin, and pyridoxine were lower than in previous summary reports. Vitamin E and pantothenic acid were the exceptions, with concentrations that were nearly identical to previous standard reports. Several other recent studies also point to current cultivars and production systems as producing lower concentrations of the essential vitamins than previously reported. The results suggest that vitamin concentrations in diets of populations using grain‐based diets from modern cereal‐production systems may require review to determine if previous assumptions of vitamin consumption are accurate.     

Structural and Functional Characteristics of Selected Soft Wheat Starches

Starches from eight soft wheat samples (two parent lines and six offspring) were isolated; relationships between their structures and properties were examined. Branch chain‐length distributions of amylopectins were determined by using high‐performance anion exchange chromatography equipped with an amyloglucosidase reactor and a pulsed amperometric detector (HPAEC‐ENZ‐PAD). Results showed that the average chain length of the eight samples varied at DP 25.6–26.9. Starch samples of lines 02, 60, 63, 95, and 114 consisted of amylopectins with more long chains (DP ≥ 37) and longer average chain length (DP 26.2–26.9) than that of other samples. These starch samples of longer branch chain length displayed higher gelatinization temperatures (55.3–56.5°C) than that of other samples (54.4–54.9°C) and higher peak viscosity (110–131 RVU) and lower pasting temperature (86.3–87.6°C) than others (83–100 RVU and 88.2–88.9°C, respectively). The M_w of amylopectins, determined by using high‐performance size exclusion chromatography equipped with multiangle laser‐light scattering and refractive index detectors (HPSEC‐MALLS‐RI), were similar for all samples (6.17 × 10⁸ to 6.97 × 10⁸). There were no significant differences in amylose and phosphorus contents between samples. These results indicated that physical properties of wheat starch were affected by the branch‐chain length of amylopectin.     

Suitability of Ontario‐Grown Hard and Soft Wheat Flour Blends for Noodle Making

This study evaluated the blending of flours made from an Ontario hard red winter wheat (HWF) and an Ontario soft red winter wheat (SWF) and compared it with a commercial standard noodle flour (control) made from Canadian Western Hard Red Spring wheat to assess the impact on white salted noodle‐making performance and texture of cooked noodles. Flour characteristics, gluten aggregation, and starch pasting properties were assessed with a farinograph, GlutoPeak tester, and Rapid Visco Analyzer, respectively. The machinability of dough was evaluated with an SMS/Kieffer rig attached to a TA.XT Plus texture analyzer. Tensile and bite tests of cooked noodles were also conducted. Blending HWF with standard noodle flour decreased gluten strength and dough extensibility linearly proportional to the blend ratio, whereas a curvilinear response from blending SWF with standard noodle flour was observed. HWF demonstrated more favorable pasting properties except for lower peak viscosity for noodle making than standard noodle flour. Below a 20% blend ratio with HWF, no significant changes were seen on dough extensibility, cooking loss, tensile properties, and bite testing parameters of cooked noodles. It can be concluded that blending HWF up to a 20% level caused no significant change in the processing properties of dough and cooked noodle quality. The results also showed that the GlutoPeak tester is a sensitive tool for evaluating gluten strength in wheat flour.     

Effect of No‐Tillage and Conventional Tillage Systems on the Chemical Composition of Soil Solid Phase and Soil Solution of Brazilian Savanna Oxisols

No‐tillage (NT) cropping systems are becoming increasingly important in the Brazilian savanna. To evaluate their sustainability we compared soil chemical properties in 1‐ to 3‐year‐old NT systems following 9 to 11 years of conventional tillage (CT) with systems where CT was continuously in place for 12 years. In the rainy season 1997/98, NT was cropped with soybean and CT with corn while in the rainy season 1998/99 both systems were cropped with soybean. Soil solid phase samples were taken from the 0—0.15, 0.15—0.3, 0.3—0.8, 0.8—1.2, and 1.2—2 m layers on three spatially separated plots under each of NT and CT. Soil solution samples were collected weekly at 0.15, 0.3, 0.8, 1.2, and 2 m soil depth during two rainy seasons (14 October to 28 April 1997/98 and 1998/99). We determined soil moisture contents, pH, the concentrations of exchangeable cations, the electrical conductivity (EC) of the soil solution, and the concentrations of Al, C, Ca, Cl^—, K, Mg, Mn, Na, NH₄⁺, NO₃^—, P, S, and Zn in solid soil and soil solution samples. Differences in soil solid phase properties and moisture content between NT and CT were small, few were significant. Under NT, the average solution pH was significantly lower (5.5), Al (26 μg l^—1), Mn (17 μg l^—1) and total organic C concentrations (TOC, 6.5 mg l^—1) were higher than under CT (pH: 6.0, Al: 14μg l ⁻¹, Mn: 14μg l ⁻¹, TOC: 5.5 mg l ⁻¹). Irrespective of the different crops in the first rainy season, under NT, the EC (205 μS cm^—1), Ca (17 mg l^—1), and Mg (2.9 mg l^—1) concentrations at 0—0.3 m depth were lower than under CT (EC: 224 μS cm^—1, Ca: 25 mg l^—1, Mg: 5.6 mg l^—1). At 1.2—2 m depth, the reverse order was observed (EC: 124 μS cm^—1 under NT and 84 μS cm^—1 under CT, Ca: 11 mg l^—1 under NT and 7.5 mg l^—1 under CT, Mg: 3.1 mg l^—1 under NT and 1.8 mg l^—1 under CT). Our results indicate that enhanced soil acidification because of higher rates of organic matter mineralization and a more pronounced nutrient leaching because of increased pore continuity may limit the sustainability of NT.     

Soil Organic Carbon and Nitrogen Stocks under Tropical Organic and Conventional Cropping Systems in Northeastern Brazil

Soil organic matter (SOM) is an essential ecosystem component whose dynamics are affected by soil management practices. To evaluate the impact of two agricultural systems (organic and conventional) on soil organic carbon (C) and nitrogen (N) stocks in a sandy soil, samples were collected from the Amway Nutrilite Brazil farm and from the Central Pivot Horticultural Farmers Association farm, both situated in the Chapada da Ibiapaba region, Ceará State, Brazil. The first area has a large‐scale Caribbean Cherry fruit production system under organic management, whereas the second represented a conventional soil cultivation condition, characterized by the use of chisel plow and disc plow, mineral fertilization, and herbicides application. Plots with and without green manure fertilization were compared in the organically cultivated systems by using soil samples collected in the rows and between the rows. Areas under native forest were also sampled to determine the steady‐state condition. Total organic C and N contents in the soil (SOC, TN) and in the humic substances were determined at the 0‐ to 5‐, 5‐ to 15‐, 15‐ to 30‐, and 30‐ to 50‐cm soil layers. In addition, oxidizible organic C fractions were measured to calculate the carbon management index (CMI). In general, total SOC levels were low, ranging from 2.5 to 12.6 g kg^?1 in the whole soil profile among the organic systems. In the upper soil layer, SOC and TN stocks were greater in the rows in response to organic fertilization. The conventional system presented lower variation on the SOC contents throughout soil layers when compared to the native forest area, indicating the direct effect of plowing on the downward SOC distribution. The CMI data confirmed the reestablishment of SOM levels in the rows of the organic managed systems in relation to the reference area, whereas the reduction of the CMI in the conventional system suggests a decline in the soil quality and greater potential for increased C losses to the atmosphere.     

Volatile Organic Compounds of Whole‐Grain Soft Winter Wheat

The aroma from volatile organic compounds (VOC) is an indicator of grain soundness and also an important quality attribute of grain foods. To identify the inherent VOC of wheat grain unaffected by fungal infestation and other extrinsic factors, grains of nine soft wheat varieties were collected at various days postanthesis (DPA) and analyzed for VOC. Ten VOC were detected in all nine varieties at all DPA. 3‐Methyl‐1‐butanol, 2‐methyl‐1‐butanol, 1‐pentanol, hexanal, and 1‐hexanol were the predominant VOC in concentration. The VOC concentration generally decreased as grain matured from 25 to 40 DPA. Hexanal and 1‐hexanol were the most abundant VOC in five and four varieties at 1.30–2.99 and 1.21–5.46 μg/kg of wheat grain, respectively, at 40 DPA. The VOC profiles of wheat grains infected with fungal diseases and stored for several months were uniquely different from that of sound grain.     

Influence of Cultivar and Environment on Water‐Soluble and Water‐Insoluble Arabinoxylans in Soft Wheat

Arabinoxylans are hydrophilic nonstarch polysaccharides found in wheat grain as minor constituents. Arabinoxylans can associate with large amounts of water through hydrogen bonding and can form oxidative gels. These properties are important factors in end‐use quality of wheat. The objective of this study was to delineate the influence of wheat cultivar and growing environment on variation in water‐soluble (WS‐AX), waterinsoluble (WI‐AX), and total (TO‐AX) arabinoxylan contents of flour and whole grain meal. This study included seven spring and 20 winter soft white wheat cultivars grown in 10 and 12 environments, respectively (each evenly split over two crop years). Univariate analysis of variance (ANOVA) and multivariate analysis of variance with canonical analysis (MANOVA) was used to evaluate sources of variation. Variation in arabinoxylan contents and absolute amounts (xylose equivalents) among the two cultivar sample sets (spring and winter) was similar, and both cultivar and environment were significant sources of variation. The cultivar‐by‐environment interaction was relatively unimportant. Results indicate that the variation in arabinoxylan content is primarily influenced by cultivar and secondarily influenced by environment. Within arabinoxylan fractions, WS‐AX content is primarily influenced by genotype, while WI‐AX content is more greatly influenced by the environment.     

Compositional Differences in Anthocyanins from Blue‐ and Purple‐Grained Spring Wheat Grown in Four Environments in Central Saskatchewan

Anthocyanins are important dietary components that play significant roles in human health because of their antioxidant and anti‐inflammatory properties. In the present study nine anthocyanin‐pigmented spring wheat lines grown at two sites in central Saskatchewan, Canada, were evaluated in terms of anthocyanin composition in comparison with four wheat checks over a two‐year period. The genotypes studied were blue‐aleurone and purple‐pericarp wheat. The anthocyanin pigments were quantified and identified with liquid chromatography and mass spectrometry. Two anthocyanin profiles were identified in the breeding lines, namely, blue profile and purple profile. Wheat lines with a purple profile had overall higher anthocyanin concentrations and more pigments than the blue‐aleurone lines. The purple profile was also characterized by the presence of acylated anthocyanins containing malonyl and succinyl substituents, but no acylated pigments were found in the blue profile. Delphinidin was the dominant aglycone in the blue profile, whereas cyanidin was the principal anthocyanidin in the purple profile. Genotype and interactions among genotype, year, and location were found to significantly influence content and composition of anthocyanin pigments. These differences in anthocyanin content and composition reflect various color characteristics and bioactivity for purple or blue wheat when utilized.     

Effects of Transgenic Cotton-Based Cropping Systems and Their Fertility Levels on Succeeding Wheat Crop

Cotton–wheat is the second most important cropping system after rice–wheat in India and Pakistan, and is practiced on about 4.02 mha. By 2010, more than 6 million Indian farmers had adopted transgenic Bt cotton on 9.4 mha—almost 90% of the country’s total cotton area. There is a paucity of information on the effects of intercropping and integrated nitrogen (N)–management practices in transgenic Bt cotton on productivity, nutrient availability, and soil biological properties in the succeeding wheat crop in a cotton–wheat system. A study was made to evaluate and quantify the residual effect of two-tiered intercropping of cotton and groundnut with substitution of 25–50% recommended dose of nitrogen (RDN) of cotton by farmyard manure (FYM) on productivity and soil fertility in a cotton–wheat system at New Delhi during 2006–2008. Wheat following groundnut-intercropped cotton receiving 50% RDN substitution through FYM had significantly 5% greater grain yield than that after sole cotton. Residual soil fertility in terms of organic carbon (C), potassium permanganate (KMnO₄)-N, and dehydrogenase activity (14%) showed an improvement under cotton + groundnut–wheat system with substitution of 50% RDN of cotton by FYM. Apparent N balance as well as actual change in KMnO₄-N at wheat harvest was negative in most of the treatments, with greater loss (–58.1) noticed under pure stand of the cotton–wheat system with 100% RDN of cotton through urea. The study suggested that inclusion of legume and organic manure in transgenic Bt-cotton–wheat system is a sustainable practice for combating escalating prices of N fertilizers with environmental issues and instability of transgenic hybrids in south Asian countries.     

No‐tillage farming: co‐creation of innovation through network building

This paper studied the development of no‐tillage by combining concepts of co‐creation of knowledge and actor‐network theory. Reconstructing the process of no‐tillage development in Switzerland has made it possible to show that no‐tillage development may be regarded as a dynamic process of co‐creation of innovation, where human and non‐human actors are building networks by reciprocally transforming and translating each other and the relations between them. This conceptualisation reveals that spread of no‐tillage requires fundamental transformations within the network of conventional plough‐tillage agriculture, including institutional arrangements, farm equipment, work organisation, concepts of agriculture and personal and professional identities. Against this background, the limited spread of no‐tillage—despite its economic and ecological advantages—can be explained by the fact that the required transformations are too radical for many agricultural actors. This conceptualisation also implies that policy interventions are not understood as top down measures that intend to induce one‐to‐one direct causal chains between knowledge and action of farmers, but as mediators in a complex process of reciprocal translations between farmers, experts and scientists, as well as many non‐human actors. We conclude that investigating processes of co‐creation of knowledge from the perspective of actor‐network theory is a promising complement to hermeneutic approaches to co‐creation of knowledge such as social learning. Copyright © 2010 John Wiley & Sons, Ltd.     

Soft Wheat Starch Pasting Behavior in Relation to A‐ and B‐type Granule Content and Composition

Flours of two soft wheat cultivars were fractionated into native, prime, tailing, A‐, and B‐type starch fractions. Starch fractions of each cultivar were characterized with respect to A/B‐type granule ratio, amylose content, phosphorus level (lysophospholipid), and pasting properties to investigate factors related to wheat starch pasting behavior. While both cultivars exhibited similar starch characteristics, a range of A‐type (5.7– 97.9%, db) and B‐type granule (2.1–94.3%, db) contents were observed across the five starch fractions. Though starch fractions displayed only subtle mean differences (<1%) in total amylose, they exhibited a range of mean phosphorus (446–540 μg/g), apparent amylose (18.7–23%), and lipid‐complexed amylose (2.8–7.5%) values, which were significantly correlated with their respective A‐ and B‐type granule contents. A‐type (compared with B‐type) granules exhibited lower levels of phosphorus, lipid‐complexed amylose, and apparent amylose, though variability for the latter was primarily attributed to starch lipid content. While starch phosphorus and lipid‐complexed amylose contents exhibited negative correlation with fraction pasting attributes, they did not adequately account for starch fraction pasting behavior, which was best explained by the A/B‐type granule ratio. Fraction A‐type granule content was positively correlated with starch pasting attributes, which might suggest that granule size itself could contribute to wheat starch pasting behavior.     

Relationship Between Soft Wheat Flour Physicochemical Composition and Cookie‐Making Performance

Nowadays in Argentina, cookies, crackers, and cakes are made of flour obtained from bread wheat with additives or enzymes that decrease the gluten strength but increase production costs. The present research work aims to study the relationship between flour physicochemical composition (particle size average [PSA], protein, damaged starch [DS], water soluble pentosans [WSP], total pentosans [TP], and gluten), alkaline water retention capacities behavior, solvent retention capacities profile (SRC) and cookie‐making performance in a set of 51 adapted soft wheat lines with diverse origin to identify better flour parameters for predicting cookie quality. Cookie factor (CF) values were 5.06–7.56. High and significant negative correlations between sucrose SRC (–0.68), water SRC (–0.65), carbonate SRC (–0.59), and CF were found, followed by lactic SRC that presented a low negative but significant correlation (r = –0.35). The flour components DS (r = –0.67), WSP (r = –0.49), and TP (r = –0.4) were negatively associated to CF. PSA showed a negative correlation with CF (r = –0.43). Protein and gluten were the flour components that affected cookie hardness, but no significant correlation were found with pentosan or DS content. A prediction equation for CF was developed. Sucrose SRC, PSA, and DS could be used to predict 68% of the variation in cookie diameter. The cluster analysis was conducted to assess differences in flour quality parameters among genotypes based on CF. Clusters 1 and 4 were typified by lower CF (5.70 and 5.23, respectively), higher DS, pentosan content, and SRC values. Cluster 2 with a relative good CF (6.47) and Cluster 3 with the best cookie quality, high CF (7.32) and low firmness, and the lowest DS, TP, WSP content, and sucrose SRC values.     

Temporal Variation of Hydro‐Physical Properties of Paddy Clay Soil under Different Rice‐Based Cropping Systems

Spatial variability of hydro‐physical properties has long been observed, whereas temporal variation is much less documented and considered in studies and applications, particularly of paddy clay soils under different cropping systems. The objective of this study was therefore to assess the seasonal‐ and inter‐seasonal variation of selected hydro‐physical properties of a paddy clay soil under different rice‐based cropping systems with contrasting tillage. In a long‐term experiment, plots were arranged in a randomized complete block design with four treatments and four replications: (i) rice–rice–rice; (ii) rice–maize–rice; (iii) rice–mung bean–rice; and (iv) rice–mung bean–maize. Soil samples were collected at three depths (0–10, 10–20 and 20–30 cm) at three times during two cropping seasons, i.e., 15 days after soil preparation (DASP), 45 DASP and 90 DASP during the winter–spring and spring–summer seasons. Results show that temporal variability of soil bulk density, macro‐porosity (MacP) and matrix‐porosity within both seasons and between seasons was limited for cropping systems with upland crop rotations, whereas within season variation was significant for rice monoculture system. Observed variation in bulk density, matrix‐porosity and MacP was mainly associated with cropping system and soil depth. Field saturated hydraulic conductivity of topsoil showed great temporal variability, both seasonal and inter‐seasonal, in correspondence with MacP (r  = 0·58). These results highlight the need of depth differentiated soil sampling and time consideration when evaluating management practices on soil physical properties and modeling the hydrological behavior of paddy soil. Copyright © 2017 John Wiley & Sons, Ltd.     

Modeling End‐Use Quality in U.S. Soft Wheat Germplasm

End‐use quality in soft wheat (Triticum aestivum L.) can be assessed by a wide array of measurements, generally categorized into grain, milling, and baking characteristics. Samples were obtained from four U.S. regional nurseries. Selected parameters included test weight, kernel hardness, kernel size, kernel diameter, wheat protein, polyphenol oxidase activity, flour yield, break flour yield, flour ash content, milling score, flour protein content, flour SDS sedimentation volume, flour swelling volume, Rapid Visco Analyzer peak paste viscosity, solvent retention capacity (SRC) parameters, total and water‐extractable arabinoxylan (TAX and WEAX, respectively), and cookie diameter. The objectives were to model cookie diameter and lactic acid SRC as well as to compare exceptionally performing varieties for each quality parameter. Cookie diameter and lactic acid SRC were modeled by using multiple regression analyses and all of the aforementioned quality parameters. Cookie diameter was positively associated with peak paste viscosity and was negatively associated with or modeled by kernel hardness, flour protein content, sodium carbonate SRC, lactic acid SRC, and water SRC. Lactic acid SRC was positively modeled by break flour yield, milling score, flour SDS sedimentation volume, and sucrose SRC and was negatively modeled by flour protein content. Exceptionally high‐ and low‐performing varieties were selected on the basis of their responses to the aforementioned characteristics in each nursery. High‐ and low‐performing varieties exhibited notably wide variation in kernel hardness, break flour yield, milling score, sodium carbonate SRC, sucrose SRC, water SRC, TAX content, and cookie diameter. This high level of variation in variety performance can facilitate selection for improved quality based on exceptional performance in one or more of these traits. The models described allow a more focused approach toward predicting soft wheat quality.     

Long‐Term Durum Wheat‐Based Cropping Systems Result in the Rapid Saturation of Soil Carbon in the Mediterranean Semi‐arid Environment

Climate, soil physical–chemical characteristics, land management, and carbon (C) input from crop residues greatly affect soil organic carbon (SOC) sequestration. According to the concept of SOC saturation, the ability of SOC to increase with C input decreases as SOC increases and approaches a SOC saturation level. In a 12‐year experiment, six semi‐arid cropping systems characterized by different rates of C input to soil were compared for ability to sequester SOC, SOC saturation level, and the time necessary to reach the SOC saturation level. SOC stocks, soil aggregate sizes, and C inputs were measured in durum wheat monocropping with (Ws) and without (W) return of aboveground residue to the soil and in the following cropping systems without return of aboveground residue to soil: durum wheat/fallow (Wfall), durum wheat/berseem clover, durum wheat/barley/faba bean, and durum wheat/Hedysarum coronarium. The C sequestration rate and SOC content were lowest in Wfall plots but did not differ among the other cropping systems. The C sequestration rate ranged from 0.47 Mg C ha⁻¹ y⁻¹ in Ws plots to 0.66 Mg C ha⁻¹ y⁻¹ in W plots but was negative (−0.06 Mg C ha⁻¹ y⁻¹) in Wfall plots. Increases in SOC were related to C input up to a SOC saturation value; over this value, further C inputs did not lead to SOC increase. Across all cropping systems, the C saturation value for the experimental soil was 57.7 Mg ha⁻¹, which was reached with a cumulative C input of 15 Mg ha⁻¹. Copyright © 2015 John Wiley & Sons, Ltd.     

Water‐Extractable Nonstarch Polysaccharide Distribution in Pilot Milling Analysis of Soft Winter Wheat

Commercial wheat (Triticum aestivum em. Thell) flour milling produces flour streams that differ in water absorption levels because of variability in protein concentration, starch damaged by milling, and nonstarch polysaccharides. This study characterized the distribution of water‐extractable (WE) nonstarch polysaccharides (NSP) in long‐flow pilot‐milling streams of soft wheat to model flour quality and genetic differences among cultivars. Existing reports of millstream analysis focus on hard wheat, which breaks and reduces differently from soft wheat. Seven soft winter wheat genotypes were milled on a pilot‐scale mill that yields three break flour streams, five reduction streams, and two resifted streams. Protein concentration increased linearly through the break streams. WENSP concentration was low and similar in the first two break streams, which are the largest break streams. Flour recovery decreased exponentially through the reduction streams; flour ash and water‐extractable glucose and galactose polymers increased exponentially through the reduction streams. Protein concentration and WE xylan concentration increased linearly through the reduction streams. The ratio of arabinose to xylose in WE arabinoxylan (WEAX) decreased through the reduction streams, and response varied among the genotypes. Flour ash was not predictive of stream composition among genotypes, although within genotypes, ash and other flour components were correlated when measured across streams. The second reduction flour stream was the largest contributor to straight‐grade flour WEAX because of both the size of the stream and the concentration of WEAX in the stream.     

Nutritional and Quality Traits of Pasta Made from SSIIa Null High‐Amylose Durum Wheat

Food products that are high in fiber and low in glycemic impact are healthier. Amylose is a form of resistant starch that mimics dietary fiber when consumed. A durum wheat (Triticum durum) line was created that lacks starch synthase IIa (SSIIa) activity, a key enzyme in amylopectin biosynthesis, by identifying a null mutation in ssIIa‐B following mutagenesis of a line that has a naturally occurring ssIIa‐A null mutation. Our objective here was to compare seed, milling, pasta, and nutritional characteristics of the SSIIa null line with a wild‐type control line. The SSIIa null line had increased amylose and grain protein with lower individual seed weight and semolina yield. Refined pasta prepared from the SSIIa null semolina absorbed less water, had increased cooking loss, had a shorter cook time, and was considerably firmer even after overcooking compared with the wild‐type line. Color of the SSIIa null cooked and uncooked pasta was diminished in brightness compared with the wild type. Nutritionally, the SSIIa null pasta had increased calories, fiber, fat, resistant starch, ash, and protein compared with the control line, along with reduced total and available carbohydrates. Pasta made from high‐amylose durum wheat provides a significant nutritional benefit along with enhanced end‐product quality via firmer pasta that resists overcooking.