Refrigerated Dough Quality of Hard Red Spring Wheat: Effect of Genotype and Environment on Dough Syruping and Arabinoxylan Production

Arabinoxylans (AX) are the main nonstarch polysaccharides found in wheat flour. Structural changes of AX in refrigerated dough are linked to deleterious effects on refrigerated dough quality during storage. The purpose of this research was to evaluate the effect of cultivar and growing environment on dough syruping during refrigerated storage in relation to apparent xylanase activity and AX chemistry in hard red spring (HRS) wheat. Eight HRS cultivars that were grown at six locations over two years in North Dakota were evaluated for dough syruping during 15 days of refrigerated storage. When compared with genotypic effect, growing environment had a greater impact on apparent xylanase activity and dough syruping; they were found to have significant associations by log‐linear regression analysis. Specifically, wheat samples produced in a dry environment had lower apparent xylanase activity and degree of dough syruping than those from a wet environment. Some HRS cultivars were identified to be consistently lower in apparent xylanase activity and dough syruping across all growing environments, indicating that those cultivars had more stability over growing environment than other cultivars. These results indicate that certain cultivars that are grown in relatively dry environments in North Dakota are more suitable for use in refrigerated dough formulations.     

Effect of variety and environmental factors on gluten proteins: an analytical, spectroscopic, and rheological study

Four cultivars of winter wheat with contrasting qualities for breadmaking were selected to study the effects of environmental factors on grain protein composition and properties. They were grown in the field and under two controlled regimens designed to mimic typical "hot/dry" and "cold/wet" conditions experienced during grain development in the United Kingdom. The composition of the gluten proteins determined by SDS-PAGE and their size distribution determined by SE-HPLC were consistent with the presence of higher proportions of high M r polymers in the two varieties with good breadmaking performance (Spark and Soissons) with limited environmental effects on these parameters. Gluten protein fractions from three of the cultivars were analyzed by Fourier transform infrared (FTIR) spectroscopy and this, combined with creep measurements using a texture analyzer, showed that a conversion from beta-turns to beta-sheets occurred during extension, irrespective of the growth conditions. However, the breadmaking varieties Soissons and Spark showed greater differences related to environmental conditions than the variety Rialto, which has poorer processing quality.     

Globulin Expression in Grain of Australian Hard Wheat Cultivars Is Affected by Growth Environment

Our aim was to study changes in wheat proteomes across different growth locations as the first step in linking protein composition with functional changes in grains produced with commercial production systems. Soluble and insoluble proteins were extracted sequentially from grain of three commercial wheat cultivars grown at four locations in New South Wales, Australia, during a single season. Bands were separated with SDS‐PAGE and identified by peptide mass fingerprinting. Quantitative changes in the electrophoretic patterns were observed mainly in the insoluble polypeptides of molecular mass 40,000–70,000 for all three cultivars grown at two of the four locations. These proteins were identified as mainly globulin and serpin isoforms, as well as triticin. Other proteins with changed expression included disease‐resistance proteins, class III peroxidase, starch branching enzyme I, β‐amylase, and storage proteins. Two‐dimensional electrophoretic analysis was performed on two of the same wheat cultivars grown at one of the locations during two consecutive seasons. Protein spots that varied between seasons consisted of globulin and serpin isoforms, triticin, HMW glutenin, γ‐gliadin, starch branching enzyme IIb, and α‐amylase. The implications of the upregulation of globulin and triticin on whole meal flour quality, through their participation in polymerization of the gluten network, are considered.     

Vicilin-like storage globulin from buckwheat (Fagopyrum esculentum Moench) seeds

An 8S storage globulin from buckwheat seed, which resembles the structure and features common to the vicilin-like family of seed storage proteins, was analyzed for this paper. It was found that expression of the 8S globulin gene precedes that of the 13S globulin (the main buckwheat storage protein) and starts from an early stage of buckwheat seed development (9-11 days after flowering), continuing to accumulate throughout seed development to contribute approximately 7% of total seed proteins. This protein fraction might be more interesting for biotechnological application than the 13S buckwheat legumin consisting of 23-25 kDa subunits reported to be the major buckwheat allergen. A partial cDNA was also isolated, showing high homology with cDNAs coding for vicilin-like storage proteins from various plant species, and its expression profile throughout seed development as well as in different buckwheat tissues was analyzed.     

NaCl胁迫对菜用大豆种子膨大初期蛋白质表达的影响

采用蛭石栽培,对开花后10 d的菜用大豆 [Glycine max (L.) Merr.] 进行100 mmol/LNaCl处理,利用双向电泳（Two-dimensional gel electrophoresis, 2-DE）技术对胁迫5 d时的种子蛋白质进行分离,并对处理与对照2-DE图谱中蛋白质表达进行比较分析。在对照和处理的2-DE图谱上均检测到327个蛋白点,有28个差异表达蛋白,其中16个较对照显著上调,另外12个显著下调。利用基质辅助激光解吸离子化飞行时间质谱（Matrix-assisted laser desorption ionization time-of-flight mass spectrometry,MALDI-TOF-MS）对其中6个丰度差异较大（丰度变化在2.5倍以上）的蛋白进行分析,通过数据库检索,从中鉴定出5个蛋白质,分别是大豆球蛋白前体G2、肌动蛋白、大豆球蛋白前体G2相似蛋白、类-微管蛋白和Kunitz型胰蛋白酶抑制剂,并对这些蛋白质在NaCl胁迫下可能的作用进行了讨论。结果表明,NaCl胁迫对菜用大豆种子膨大初期的蛋白质代谢产生了显著影响,肌动蛋白、类-微管蛋白和Kunitz型胰蛋白酶抑制剂可能参与了对NaCl胁迫的应答反应。     

灌水和生长调节剂对有色小麦产量和品质的影响

以有色小麦皖麦38、绿麦1号和kz6061为材料,在大田条件下,研究灌水和生长调节剂对有色小麦产量和品质的影响。结果表明,灌水处理对有色小麦千粒重、容重、籽粒产量和蛋白质产量影响不显著,灌3水较灌2水处理显著提高有色小麦醇溶蛋白含量,而显著降低干、湿面筋含量。不同粒色小麦的籽粒产量和蛋白质产量差异显著,kz6061的籽粒产量和蛋白质产量均显著高于皖麦38和绿麦1号。蛋白质及其组分含量、沉降值、面筋含量和面筋指数在不同粒色小麦中差异显著,沉降值和面筋指数以皖麦38最高,干、湿面筋含量以kz6061最高。生长调节剂处理对皖麦38的清蛋白和球蛋白,绿麦1号的球蛋白,kz6061的清蛋白、球蛋白、醇溶蛋白和谷蛋白含量均有一定影响,对有色小麦面筋指数亦有显著影响。     

Effect of Puroindolines on the Breadmaking Properties of Wheat Flour

The role of lipid-binding proteins from wheat seed (puroindolines) on the breadmaking properties of wheat flour was investigated by determining the relationship between breadmaking quality and puroindoline content in samples of 32 wheat cultivars. An inverse relationship was mainly explained by the link between hardness and puroindoline contents. This link is in agreement with previous results which have shown a close structural identity between basic friabilins and puroindolines. Next, the effect of puroindolines in breadmaking was investigated by performing reconstitution experiments with two puroindoline-free hard cultivars of opposite quality (Florence Aurore and Ecrin) as indicated in the screened wheat sample. Addition of 0.1% puroindolines to these flours drastically modified both the rheological properties of doughs and the structure of the bread crumb. Puroindolines are essential to the foaming properties of dough liquor, and a close relationship was found between the fine grain crumb provided by reconstituted flours with puroindolines and the fine structure of corresponding dough liquor foams. The effect of puroindolines on bread volume was mainly related to the rheological properties of wheat doughs.     

High molecular weight glutenin subunits in some durum wheat cultivars investigated by means of mass spectrometric techniques

The primary structures of high molecular weight glutenin subunits (HMW-GS) of 5 Triticum durum Desf. cultivars (Simeto, Svevo, Duilio, Bronte, and Sant'Agata), largely cultivated in the south of Italy, and of 13 populations of the old spring Sicilian durum wheat landrace Timilia (Triticum durum Desf.) (accession nos. 1, 2, 3, 4, 7, 8, 9, 13, 14, 15, SG1, SG2, and SG3) were investigated using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) and reversed-phase high performance liquid chromatography/nanoelectrospray ionization mass spectrometry (RP-HPLC/nESI-MS/MS). M(r) of the intact proteins determined by MALDI mass spectrometry showed that all the 13 populations of Timilia contained the same two HMW-GS with 75.2 kDa and 86.4 kDa, whereas the other durum wheat cultivars showed the presence of the expected HMW-GS 1By8 and 1Bx7 at 75.1 kDa and 83.1 kDa, respectively. By MALDI mass spectrometry of the tryptic digestion peptides of the isolated HMW-GS of Timilia, the 1Bx and 1By subunits were identified as the NCBInr Acc. No AAQ93629, and AAQ93633, respectively. Sequence verification for HMW-GS 1Bx and 1By both in Simeto and Timilia was obtained by MALDI mass mapping and HPLC/nESI-MSMS of the tryptic peptides. The Bx subunit of Timila presents a sequence similarity of 96% with respect to Simeto, with differences in the insertion of 3 peptides of 5, 9, and 15 amino acids, for a total insertion of 29 amino acids and 25 amino acid substitutions. These differences in the amino acidic sequence account for the determined Δm of 3294 Da between the M(r) of the 1Bx subunits in Timilia and Simeto. Sequence alignment between the two By subunits shows 10 amino acid substitutions and is consistent with the Δm of 148 Da found in the MALDI mass spectra of the intact subunits.     

Identification and quantification of xanthophyll esters, carotenes, and tocopherols in the fruit of seven Mexican mango cultivars by liquid chromatography-atmospheric pressure chemical ionization-time-of-flight mass spectrometry [LC-(APcI(+))-MS

A liquid chromatography-mass spectrometry (LC-MS) method was developed to simultaneously identify and quantify carotenoids and tocopherols in the fruit of seven mango cultivars grown in Mexico. Fruit maturity was characterized objectively, and carotenoids and tocopherols were isolated by solvent extraction and analyzed by HPLC coupled to a C30 stationary phase and diode array, fluorescence, and mass (time-of-flight) detectors. All cultivars had a similar carotenoid pattern, in which all-trans-beta-carotene and dibutyrates of all-trans-violaxanthin and 9-cis-violaxanthin were the most abundant. The content of all-trans-beta-carotene ranged between 0.4 and 2.8 mg/100 g, and 'Haden' and 'Ataulfo' mangoes had the highest amount. The amounts of all-trans-violaxanthin and 9-cis-violaxanthin (as dibutyrates) ranged between 0.5 and 2.8 mg/100g and between 0.4 and 2.0 mg/100 g, respectively. The content of alpha-tocopherol was low (200-500 microg/100 g). The results of this study indicate that all-trans-beta-carotene, all-trans-violaxanthin, and 9-cis-violaxanthin are the most abundant carotenoids in mango grown in Mexico.     

Proteomic response to intracellular proteins of Monascus pilosus grown under phosphate-limited complex medium with different growth rates and pigment production

Monascus pigments are important colorings in food applications. Rice containing potassium phosphate and sodium nitrate was reported as a good pigment-producing medium for Monascus in previous studies. We found that the lack of potassium phosphate in this medium depressed red pigment production in cultivated Monascus pilosus. However, the influence of phosphate limitation on the biochemical metabolisms concerning culture growth and pigment production in Monascus remains unknown. Here, we used proteomic analysis by two-dimensional gel electrophoresis, matrix-assisted laser desorption ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/TOF MS), tandem mass spectrometry (MS/MS), and database interrogation to separate and identify the proteins of M. pilosus grown between the lack of potassium phosphate and the control media. Phosphate limitation to this complex medium induced an up-regulation of aldehyde dehydrogenase and several glycolytic enzymes in Monascus relative to the control. In contrast, the metabolic enzymes such as glucosamine:fructose-6-phosphate aminotransferase and ADP-ribosylation factor 1 were up-regulated in the control.     

Identification and quantification of betalains from the fruits of 10 mexican prickly pear cultivars by high-performance liquid chromatography and electrospray ionization mass spectrometry

Qualitative and quantitative analyses of betalain pigments in 10 cultivars/lines of prickly pear (Opuntia spp.) fruit grown in Mexico were conducted with reverse phase high-performance liquid chromatography-diode array detection (HPLC-DAD) coupled with electrospray mass spectrometry (ESI-MS). Betacyanins and betaxanthins were identified by comparison with the UV/vis and mass spectrometric characteristics as well as the retention times of semisynthesized reference betaxanthins. Data revealed that the ratio and concentration of betalain pigments are responsible for the color in the different cultivars, showing the highest betalains content in the fruit of purple colored Camuesa (O. robusta Wendl.) (8.1 mg/g dry fruit), which is comparable to that found in red beet Beta vulgaris L. ssp. Var. Pablo) (8.6 mg/g dry tissue). Yellow betalains were absent in Reyna (O. alba-carpa) prickly pear cultivar. A total of 24 known/unknown betalains were present in the prickly pear fruit samples studied, including 18 betaxanthins and 6 betacyanins. Our results indicate that prickly pear cultivars can be considered as a potential source of yellow and red natural colorants.     

施氮水平对小麦子粒蛋白质组分和加工品质的影响

选用两个优质小麦品种烟农15号和济麦19号,研究了施氮水平对小麦子粒蛋白质组分和加工品质的影响。田间试验设4个施氮水平,即N.0、120、240和360.kg/hm2。结果表明,施用氮肥对子粒发育前期清蛋白和球蛋白含量有明显的提高效应,但随子粒灌浆充实,这种效应逐渐削弱,到成熟期,施氮处理虽能提高子粒清蛋白和球蛋白的含量,但不同施氮水平间无明显差异。施用氮肥还能显著地提高子粒醇溶蛋白和麦谷蛋白的含量,尤其是子粒麦谷蛋白的含量,使子粒麦谷蛋白/醇溶蛋白比值提高。试验还表明,施用氮肥能明显提高子粒湿面筋含量,延长面团形成时间、面团稳定时间和断裂时间。综合分析看出,子粒醇溶蛋白和麦谷蛋白的含量以及麦谷蛋白/醇溶蛋白比值是影响小麦加工品质的重要因素,可以作为小麦品质育种中亲本及后代材料的选择、评价和优质栽培技术评价的依据。     

Ensiling properties of sweet sorghum

Abstract

Sweet sorghum [Sorghum bicolor (L.) Moench] cultivars have been bred for high sugar content; with accompanying adequate forage yield, the crop may offer potential for ensiling. “Wray”; sweet sorghum, a good sugar producer, was grown under field conditions to determine nutritional quality and subsequent animal performance of silage from the yield. In one experiment, “Wray”; was compared to “FS‐5”;, medium‐tall forage sorghum, at four reproductive stages of growth, in regard to agronomic characteristics and chemical composition. In another study, the “Wray”; sweet sorghum was harvested in early and late reproductive stages and stored in experimental silos. Ensiling losses were measured; in addition, the silages were offered to sheep to determine in vivo digestibility (IVODMD) and intake. In the first experiment, dry matter yields of both sweet and forage sorghum increased during the reproductive period, from 6.2 to 11.9 and 7.7 to 13.9 Mg/ha, respectively; at maturity, grain yields were 651 and 3,526 kg/ha, respectively. Total available carbohydrates tended to be higher in the forage type (23.4%) than in the sweet sorghum (19.9%). Average in vitro dry matter disappearance (IVDMD) was similar for both sorghums at 60.2%, but sweet sorghum IVDMD tended to be higher than forage sorghum at the hard‐dough stage (61.4 versus 55.1%) . In the second experiment, intake was greater when lambs were offered hard‐dough stage silage (1,240 g/lamb/day) versus bloom‐stage silage (878 g/lamb/day), even though IVODMD was similar (average 60.6%) at both harvest stages. The silages appeared to be properly ensiled, as silage pH was less than 4.0; however, effluent and dry matter losses were greater with bloom‐stage silage. These differences probably were due to the slight dry matter differential between the two <22.3 and 26.6%, respectively). To maximize yield, sweet sorghum should be ensiled at the hard‐dough stage. Resulting silage may be higher in digestible dry matter than that of medium‐tall forage sorghums, which produce grain.     

Effect of Glyphosate Application on Hagberg Falling Number of Wheat

A study was conducted to investigate management of Hagberg Falling Number (HFN) by creating more homogenous wheat through glyphosate applications at soft and hard dough stages individually, without compromising wheat quality. The effect of the treatments varied over cultivars and seasons. Thousand kernel mass (2003/04), hectolitre mass (2003/04 and 2004/05), and protein content (2003/04 and 2004/05) were negatively affected by soft dough stage treatments for all three cultivars included in the study. Days to harvest and growing degree days were significantly reduced with the soft dough treatment. Yield and preharvest sprouting were not affected. α-Amylase activity varied over season, cultivar, and treatment. HFN measured for Tugela-DN treated at soft dough stage produced a significantly higher HFN compared with the control (2004/05). None of the other cultivars at the various treatments indicated any HFN response to glyphosate application. Germination was severely affected by soft dough stage glyphosate application in the first year of evaluation. Studies into the effect of the various treatments on the repeatability of the HFN test, indicated that glyphosate treatment managed to produce a certain amount of stability for two of the three cultivars, but the treatment that resulted in the stability varied between seasons.     

Adaptability of chickpea in northern high latitude areas—Maturity responses

Global climate warming may allow ‘warm-season’ chickpea (Cicer arietinum L.) to be better adapted to the cool, high latitude areas of the world. Chickpea has a strong indeterminacy and continued growth of vegetative tissues during the later part of the reproduction period often delays maturity in high latitude areas. This study was conducted to determine the adaptability of chickpea and evaluate the relative importance of changing environments and optimizing crop management options in affecting crop maturity. Four cultivars were grown on barley and wheat stubble, and on summerfallow using rates of 0, 28, 64, 84, and 112 kg N ha^?1 of fertilizer with and without Rhizobium inoculant at six environments in Saskatchewan, Canada, during 2004–2006. Maturity of chickpea ranged from 91 d in 2006 to 136 d in 2004. About 90% of the variation in maturity was due to environments, with the remaining variation related to cultivars, seedbed conditions, and soil fertility. The cultivars ‘Amit’ and ‘CDC-Anna’ matured 2–7 d earlier than ‘CDC-Frontier’ and ‘CDC-Xena’ averaged across diverse environments. Under cool and wet environments, chickpea grown on cereal stubble matured 7–15 d earlier than those grown on summerfallow; chickpea grown at moderate rates of N fertilizer (28–84 kg ha^?1) without Rhizobium inoculant matured 15 d earlier than the crop receiving no-N fertilizer with or without inoculation. Under dry and hot environments, only marginal differences in maturity were observed among applied treatments. Our results indicate that chickpea maturity can be advanced as many as 15 days which can help minimize the risk of crop failure due to immaturity; this is achievable through the adoption of early-maturing cultivars, use of moderate rates of N fertilizer, and selection of cereal stubble as preferential seedbed. With current genotypes of chickpea, there is still considerably high risk of adapting this ‘warm-season’ crop in northern high latitude areas because of large environmental variability, but this risk might be reduced with continued global warming.     

VARIATION IN PHOSPHORUS EFFICIENCY AMONG BRASSICA CULTIVARS I: INTERNAL UTILIZATION AND PHOSPHORUS REMOBILIZATION

Plants have adapted a number of mechanisms to cope with widespread phosphorus (P) deficiency in arable lands. Crop species and even cultivars differ widely in one or more of these adaptive mechanisms hence, in P efficiency. Identification of these mechanisms is pre-requisite for long term breeding programs. Two independent experiments were conducted to study the possible mechanisms of P efficiency in Brassica cultivars. Eight Brassica cultivars (‘B.S.A.’, ‘Toria’, ‘Toria Selection’, ‘Brown Raya’, ‘Peela Raya’, ‘Dunkeld’, ‘Rainbow’, and ‘CON-1’) were selected on the basis of differences in growth under P deficiency from preliminary experiment. In the first experiment, cultivars were grown for 40 days in sand supplied either with sparingly soluble phosphate rock (PR) or soluble mono-ammonium phosphate (MAP). Cultivars differed significantly (P<0.05) for biomass production, P contents and P use efficiency. Low P availability in PR treatment resulted in significantly lower dry weights and P contents than those grown with MAP. The cultivars ‘Rainbow’, ‘Brown Raya’ and ‘Dunkeld’ accumulated more biomass (3.2 g/pot) and P contents (3.0 mg/pot) than other cultivars when grown with PR. Root dry weight was significantly correlated with shoot dry weight, shoot P content and total P content (r > 0.65) indicating significance of improved root growth for P acquisition. While in the second experiment cultivars were grown with adequate P for 30 days and then P was withdrawn from the nutrient solution by replacing fresh P free nutrient solution for 10 days. Induced P deficiency increased P contents in young leaves by two folds indicating remobilization of P from older leaves and shoot. Nonetheless cultivars varied for remobilization but differences in P remobilization could not explain the differences in P utilization efficiency among cultivars. Hence further experimentation to study root morphology, P uptake, and organic acid exudation by these cultivars in relation to P deficiency is recommended.     

Burning season influences the response of bird assemblages to fire in tropical savannas

Fire plays a pivotal role in structuring ecosystems and often occurs as a human-mediated disturbance for land management purposes. An important component of fire regime is the season of burn. In tropical savannas, most fire management occurs during the dry season; however, wet season burning is often used for pastoral management and may be useful for controlling introduced plant species. We used replicated, experimental fire treatments (unburnt, dry season burnt and wet season burnt), spanning two habitats (riparian and adjacent open woodland), to examine the short- (within 12 months of fire) and longer-term (within four years of fire) changes of bird assemblages in response to wet and dry season burning in tropical savannas of northern Australia. Within 12 months of fire, we observed higher abundances of birds in the burnt treatments, although some species (e.g., red-backed fairy-wren, Malurus melanocephalus) were rarely observed in burnt sites. Dry season burnt sites contained higher abundances of insectivores and granivores, while wet season burnt sites had more carnivores. Four years following burning, dry season burnt sites were characterized by lower abundances, especially of nectarivores and granivores. Dry season burnt sites also contained a different assemblage than wet season burnt sites, but few differences were observed between wet season burnt and unburnt sites. Our results confirm that differences in fire regimes can substantially alter bird assemblages, especially in riparian zones, and emphasize the importance of incorporating burning season in fire management strategies.     

Effect of Microbial Transglutaminase on Dough Proteins of Hard and Soft (Triticum aestivium) and Durum (Triticum durum) Wheat Cultivars

Microbial transglutaminase (MTGase), a protein‐glutamine γ‐glutamyl transferase (E.C. 2.3.2.13), catalyzes acyl transfer reactions by introducing a covalent cross‐link between l ‐lysine and l ‐glutamine residues. The use of this enzyme has been proposed as an improver to increase dough strength. The objective of this study was to assess and compare the effect of MTGase on different fractions of dough proteins found in hard, soft, and durum wheat. Three different concentrations of the MTGase (0, 5, and 10U/g of gluten) were tested. Moisture, protein, and dry gluten contents were determined for each concentration in addition to rheological measurements done with the farinograph. Following each treatment, the dough proteins were extracted and analyzed by SE‐HPLC and RP‐HPLC. Soluble polymeric protein, gliadins, albumins, and globulins were quantified in addition to the gliadin subclasses and glutenin subunit types. The combustion procedure was used to determine the amount of insoluble polymeric protein. Differences were observed in susceptibility to MTGase catalysis among the dough proteins of the cultivars studied: the cultivar Cortazar (soft wheat) was the most susceptible. The proteins of this cultivar had a characteristically higher amount of ω and α+β gliadins when compared with the other cultivars. As reported earlier, solubility of high molecular weight glutenin subunits and ω‐gliadins was reduced because of the MTGase treatment. However, all gliadin subclasses, including the γ and α+β gliadins, also participated in cross‐linking. The proteins of the cultivar Altar (durum wheat) were the least susceptible to the effects of MTGase. Albumins and globulins did not show any reduction in solubility, implying that they did not participate in cross‐linking.