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PubMed2005

Free radical scavenging properties and phenolic content of Chinese black-grained wheat.

Free radical scavenging properties and phenolic content of extracts from a novel Chinese black-grained wheat were evaluated for comparison with selected wheat controls. Extracts of bran and whole meal were compared for their scavenging activities against the 2,2-diphenyl-1-picryhydrazyl (DPPH) free radical. The total phenolic content and phenolic acid levels were determined using colorimetric and high-performance liquid chromatography (HPLC) methods, respectively. There were significant differences in radical scavenging activities and phenolic contents among bran or whole meal samples of Chinese black-grained wheat and selected wheat controls. Chinese black-grained wheat had the strongest scavenging activity and the highest total phenolic content among the wheat samples. The scavenging activity and total phenolic content of wheat bran was generally twice as high as that of whole meal. A positive correlation was found between DPPH radical scavenging activity and total phenolic content of bran (R = 0.86) and whole meal (R = 0.96). In addition, HPLC analysis detected the presence of gallic, p-hydroxybenzoic, caffeic, syringic, p-coumaric, vanillic, gentisic, o-coumaric acid, and ferulic acids in wheat bran. Ferulic acid content was highest among the phenolic acids. Chinese black-grained wheat may be considered as a potential source of natural antioxidants given its high free radical scavenging ability and phenolic content. Additional research is needed to further investigate other phenolic compounds and evaluate their contribution to the antioxidant activity in order to understand the nutraceutical value of the novel black-grained wheat genotype.

Biphenyl Compounds↗
PubMed1999

Identification and characterization of T3/T7 bacteriophage-like RNA polymerase sequences in wheat.

Using PCR-based methods, we assembled two wheat cDNA sequences, wheat-G and wheat-C, that encode T3/T7 bacteriophage-like RNA polymerases (RNAPs) sharing 45% amino acid identity. In phylogenetic analyses using maximum likelihood, parsimony and distance methods, the predicted protein sequence of wheat-G (1005 amino acids, 113 kDa) clusters with sequences of previously assigned mitochondrial RNAPs from dicotyledonous plants (Arabidopsis thaliana, Chenopodium album); likewise, in such analyses, the wheat-C sequence (949 amino acids, 107 kDa) affiliates specifically with the Arabidopsis sequence that encodes a phage-like RNAP thought to function in chloroplasts. To confirm biochemically the assignment of the gene encoding the putative wheat mitochondrial RNAP, we isolated a ca. 100 kDa wheat mitochondrial protein that is enriched in fractions displaying specific in vitro transcription activity and that reacts with an antibody raised against a recombinant maize phage-type RNAP. Internal peptide sequence information obtained from the 100-kDa polypeptide revealed that it corresponds to the predicted wheat-G cDNA sequence, providing direct evidence that the wheat-G gene (which we propose to call RpoTm) encodes the wheat mitochondrial RNAP.

Amino Acid Sequence↗
PubMed1999

Wheat allergy: diagnostic accuracy of skin prick and patch tests and specific IgE.

BACKGROUND: Food allergy makes an important contribution to the pathogenesis of atopic eczema in infants. However, clinical data on cereal allergy are scanty. The objective was to study the relevance of patch testing, skin prick tests, and the concentration of wheat-specific IgE antibodies (CAP RAST) in correlation with oral wheat challenge in infants with suspected wheat allergy. In particular, we aimed to determine whether the patch test could increase the diagnostic accuracy in detecting wheat allergy. METHODS: The study material comprised 39 infants under the age of 2 years. Of these patients, 36 were suffering from atopic eczema and three had only gastrointestinal symptoms. The patients were subjected to a double-blind, placebo-controlled or open wheat challenge. Wheat-specific IgE was measured by CAP RAST, and skin prick and patch tests were performed. RESULTS: Of the total 39 wheat challenges, 22 (56%) were positive. Of the positive reactions, five involved immediate-type skin reactions over a period of 2 h from the commencement of the challenge. In 17 patients, delayed-onset reactions of eczematous or gastrointestinal type appeared. Of the infants with challenge-proven wheat allergy, 20% showed elevated IgE concentrations to wheat, 23% had a positive skin prick test, and 86% had a positive patch test for wheat. The specificities of CAP RAST, skin prick tests, and patch tests were 0.93, 1.00, and 0.35, respectively. CONCLUSIONS: Our study demonstrated that patch testing with cereals will significantly increase the probability of early detection of cereal allergy in infants with atopic eczema and is helpful in the planning of successful elimination diets before challenge. The specificity of the patch test was lower than that of other tests. Therefore, confirmation of the diagnosis with the elimination-challenge test is essential in patients with positive patch test results.

Allergens↗
PubMed2002

Differential effects of cultivated and wild barley 5H chromosomes on heading characters in wheat-barley chromosome addition lines.

Wheat (Triticum aestivum L.)-barley (Hordeum vulgare L.) chromosome addition lines are possible vehicles for transferring barley genes into wheat. The barley 5H chromosome has genetic effects on the heading characters in wheat-barley addition lines: accelerating narrow-sense earliness, decreasing vernalization requirement and/or increasing photoperiodic sensitivity. To elucidate the effects of different 5H chromosomes under an identical wheat genetic background, two wheat-barley addition lines, i.e. cultivated barley 'New Golden' 5H chromosome added to 'Shinchunaga' wheat (Shi-NG5H) and wild barley H. vulgare ssp. spontaneum 5H chromosome added to 'Shinchunaga' wheat (Shi-Spn5H), were examined for their heading characters. The addition line Shi-NG5H showed a significantly lower vernalization requirement in comparison with 'Shinchunaga' wheat, whereas Shi-Spn5H did not. Furthermore, both NG5H and Spn5H chromosomes shortened narrow-sense earliness and increased photoperiodic sensitivity in wheat, but the effects of Spn5H were weaker than those of NG5H. The fact that NG5H and Spn5H showed differential effects on heading characters in wheat demonstrated that the heading characters were altered by the function of the barley genes located on 5H chromosomes, not merely by the aneuploid effect alone.

Chromosomes, Plant↗
PubMed1994

Xylanase in broiler diets with differences in characteristics and content of wheat.

1. Experiments were conducted to measure the effect of xylanase supplementation on the performance of broilers fed on wheat-based diets containing high and low extract viscosity wheat (experiment 1), baking and feeding quality wheat (experiment 2) and with variation in wheat content (experiment 3). 2. Xylanase supplementation improved food conversion ratios by 2.2-2.9% and body weight gain by 0.2-2.5%. This was independent of wheat characteristics but slightly dependent on the wheat content of the diet. These effects were related to a lowering of digesta viscosity. 3. Differences in extract viscosity of wheat were not reflected in broiler digesta viscosity. 4. Reduction of digesta viscosity resulted in only a slight improvement of litter score. Reduced intestinal viscosity decreased relative pancreas weight and to a lesser extent relative small intestinal weight. 5. Baking quality wheat Baldus gave better performance than the feed quality wheats Apollo and Slejpner. 6. It was concluded that xylanase supplementation of wheat-based diets invariably had a positive effect on broiler performance.

Analysis of Variance↗
PubMed2006

Development and application of analytical methods for the determination of mycotoxins in organic and conventional wheat.

The aim of this study was to develop a multicomponent analytical method for the determination of deoxynivalenol (DON), ochratoxin A (OTA) and zearalenone (ZEN), nivalenol (NIV), 3-acetyl-DON (3-acDON), 15-acetyl-DON (15-acDON), zearalenol (ZOL) and citrinin (CIT) in wheat. It also aimed to survey the presence and amounts of DON, OTA and ZEN in Belgian conventionally and organically produced wheat grain and in wholemeal wheat flours. After solvent extraction, an anion-exchange column (SAX) was used to fix the acidic mycotoxins (OTA, CIT), whilst the neutral mycotoxins flowing through the SAX column were further purified by filtration on a MycoSep cartridge. OTA and CIT were then analysed by high-performance liquid chromatography (HPLC) using an isocratic flow and fluorescence detection, while the neutral mycotoxins were separated by a linear gradient and detected by double-mode (ultraviolet light fluorescence) detection. The average DON, ZEN and OTA recovery rates from spiked blank wheat flour were 92, 83 and 73% (RSDR = 12, 10 and 9%), respectively. Moreover, this method offered the respective detection limits of 50, 1.5 and 0.05 microg kg-1 and good agreement with reference methods and inter-laboratory comparison exercises. Organic and conventional wheat samples harvested in 2002 and 2003 in Belgium were analysed for DON, OTA and ZEN, while wholemeal wheat flour samples were taken from Belgian retail shops and analysed for OTA and DON. Conventional wheat tended to be more frequently contaminated with DON and ZEN than organic samples, the difference being more significant for ZEN in samples harvested in 2002. The mean OTA, DON and ZEA concentrations were 0.067, 675 and 75 microg kg-1 in conventional samples against 0.063, 285 and 19 microg kg-1 in organically produced wheat in 2002, respectively. Wheat samples collected in 2003 were less affected by DON and ZEN than the 2002 harvest. Organic wholemeal wheat flours were more frequently contaminated by OTA than conventional samples (p < 0.10). The opposite pattern was shown for DON, organic samples being more frequently contaminated than conventional flours (p < 0.10).

Belgium↗
PubMedDate not supplied

The effects of milling and processing on wheat contaminated with ochratoxin A.

Samples of sound home-grown wheat (one hard and one soft milling) were obtained, cleaned, and gamma-irradiation used to reduce numbers of viable naturally-occurring fungi. Each sample was inoculated with a toxigenic strain of Penicillium verrucosum and monitored for ochratoxin A formation. When ochratoxin A had reached a level of 60 micrograms/kg, the samples were milled into ten fractions which were analysed for ochratoxin A by an HPLC method with immunoaffinity column clean-up. Each straight-run white flour was baked into bread which was analysed in the same way. Relationships between ochratoxin A levels in naturally-contaminated wheat and the products of milling and baking were established. The recovery of ochratoxin A in wholemeal compared with the cleaned wheat was essentially complete and no significant loss occurred on baking white or wholemeal flour into bread. Recoveries in the straight-run white flours, however, were only approximately one-third for the hard wheat and two-thirds for the soft wheat of the ochratoxin A in the uncleaned wheat. The reason for this was that a much higher proportion of the ochratoxin A was found in the bran and offal fractions from hard wheat than from soft. Conversely, a much higher proportion of the ochratoxin A was found in the reduction flour from soft wheat than from hard. Scouring was examined as a possible method of decontamination of wheat prior to milling. This process removes a proportion of the pericarp (bran coat) prior to milling. The results of the study confirmed that scouring reduced the ochratoxin A level in white and wholemeal flour three-fold for both the hard and soft wheat.

Bread↗
PubMed2002

High-fiber oat cereal compared with wheat cereal consumption favorably alters LDL-cholesterol subclass and particle numbers in middle-aged and older men.

BACKGROUND: No studies have examined whether increased consumption of oat cereal, rich in soluble fiber, favorably alters lipoprotein particle size and number. OBJECTIVE: We examined the effects of large servings of either oat or wheat cereal on plasma lipids, lipoprotein subclasses, lipoprotein particle diameters, and LDL particle number. DESIGN: Thirty-six overweight men aged 50-75 y were randomly assigned to consume daily for 12 wk either oat or wheat cereal providing 14 g dietary fiber/d. Before and after the intervention, plasma lipid and lipoprotein subclasses were measured with proton nuclear magnetic resonance spectroscopy, and whole-body insulin sensitivity was estimated with the frequently sampled intravenous-glucose-tolerance test. RESULTS: Time-by-treatment interactions (P < 0.05) for LDL cholesterol (oat: -2.5%; wheat: 8.0%), small LDL cholesterol (oat: -17.3%; wheat: 60.4%), LDL particle number (oat: -5.0%; wheat: 14.2%), and LDL:HDL cholesterol (oat: -6.3%; wheat: 14.2%) were observed. Time-by-treatment interactions were nearly significant for total cholesterol (oat: -2.5%; wheat: 6.3%; P = 0.08), triacylglycerol (oat: -6.6%; wheat: 22.0%; P = 0.07), and VLDL triacylglycerol (oat: -7.6%; wheat: 2.7%; P = 0.08). No significant time-by-treatment interactions were observed for HDL cholesterol, HDL-cholesterol subclasses, or LDL, HDL, and VLDL particle diameters. Insulin sensitivity did not change significantly with either intervention. CONCLUSIONS: The oat compared with the wheat cereal produced lower concentrations of small, dense LDL cholesterol and LDL particle number without producing adverse changes in blood triacylglycerol or HDL-cholesterol concentrations. These beneficial alterations may contribute to the cardioprotective effect of oat fiber.

Aged↗
PubMed1992

Long-term wheat germ intake beneficially affects plasma lipids and lipoproteins in hypercholesterolemic human subjects.

In previous short-term studies in rats and humans, the ingestion of raw wheat germ lowered plasma triglycerides and cholesterol. Thus, the present study was designed to investigate the possible long-term effects of wheat germ intake. Diet supplementation with raw wheat germ or partially defatted wheat germ was tested in two separate groups of 10 and 9 free-living human subjects, respectively. They all exhibited hypercholesterolemia (6.14-9.67 mmol/L cholesterol) and 11 had hypertriglyceridemia. None was diabetic. Fasting blood samples were taken at the beginning of the study, after 4 wk of 20 g/d wheat germ intake, after 14 additional weeks of 30 g/d wheat germ intake and after 12 wk without any supplementation. Dietary records were kept for seven and three consecutive days, before and during the wheat germ intake periods, respectively. Raw wheat germ intake significantly decreased plasma cholesterol (-8.7%) and tended to reduce VLDL cholesterol (-19.6%) after 4 wk. After 14 additional weeks, plasma cholesterol (-7.2%) and LDL cholesterol (-15.4%) remained lower and plasma triglycerides (-11.3%) tended to be lower. The apo B:apo A1 ratio significantly decreased after both periods. Partially defatted wheat germ transiently decreased plasma triglycerides and cholesterol after a 4-wk intake. The present data indicate that wheat germ reduces cholesterolemia in the long term and could play a beneficial role in the dietary management of type IIa and IIb hyperlipidemia.

Adult↗
PubMed1996

Wheat antigen exposure assessment for epidemiological studies in bakeries using personal dust sampling and inhibition ELISA.

BACKGROUND: Asthma in bakery workers caused by exposure to wheat flour proteins is an important occupational health problem. Until recently, gravimetric dust measurements were the only available technique for quantitative exposure assessment in bakeries. However, it is questionable whether dust levels are a good exposure parameter or only give a crude approximation of the actual flour allergen concentration. OBJECTIVE: In the present study we have investigated a method to measure wheat flour antigens with immunochemical methods. METHODS: Wheat flour antigens were measured in 449 personal dust samples taken in bakeries, using enzyme-linked immunosorbent assay (ELISA) inhibition and an anti-wheat IgG4 serum pool. Western-blotting was performed to compare the wheat flour proteins detected by IgE and IgG4. RESULTS: Electrophoresis and immunoblotting showed that many wheat flour proteins can bind IgG4 and IgE, but also a reasonable similarity in major allergens detected by our IgG4-serum pool and IgE-positive sera. Inhibition tests showed some cross-reactivity with some cereal species, but not with other ingredients used in bakeries. In bakeries, large differences in personal airborne flour levels were found between occupational titles. For several groups clear differences in wheat antigen exposure levels existed, where no differences in dust exposure levels could be found. The relationship between dust and wheat antigen exposure varied considerably, depending on the specific bakery occupation, the size of the bakery, and the type of product produced by the bakery. This study also shows that personal sampling of wheat antigens is possible on a large scale and can be used for epidemiological field studies. CONCLUSION: Measurement of airborne wheat antigens in bakeries is a more specific and sensitive measurement tool than measuring dust samples, and will probably be essential for epidemiologic field studies focusing on exposure-response relationships.

Air Pollutants, Occupational↗
PubMed2005

Effects of Fusarium toxin-contaminated wheat grain on nutrient turnover, microbial protein synthesis and metabolism of deoxynivalenol and zearalenone in the rumen of dairy cows.

The aim of the present study was to examine the effects of feeding Fusarium toxin-contaminated wheat to dairy cows on nutrient utilization in the rumen and on duodenal flow of deoxynivalenol (DON), zearalenone (ZON) and their metabolites. Six dairy cows fitted with a large rumen cannula and a simple T-shaped cannula at the proximal duodenum was used in two experiments. The experiments included a control period in which the uncontaminated control wheat was fed and a period in which the control wheat was replaced by the Fusarium toxin-contaminated wheat (8.05 and 7.15 mg DON/kg and 0.26 and 0.1 mg ZON/kg in Expts 1 and 2 respectively). The wheat portion of the daily ration amounted to 50% on a dry matter (DM) basis and rations were completed with hay or grass silage. Five of the six cows were non-lactating and the total daily DM-intake ranged between 4 and 12 kg. The pH-values and the concentration of volatile fatty acids in ruminal fluid were not significantly influenced by feeding the contaminated wheat. In contrast, the postprandial ammonia concentration was consistently higher when the mycotoxin-contaminated wheat was fed. Moreover, the flow of microbial protein and utilizable protein at the duodenum were reduced at the same time. The concentrations of DON and ZON and of their metabolites in freeze-dried duodenal digesta were either not detectable or negligible during the control periods whereas distinct concentrations were measured during the periods where the contaminated wheat was fed. DON was nearly completely metabolized to de-epoxy-DON and the flow at the duodenum ranged between 4% and 28% of DON-intake. The ZON metabolites alpha-zearalenol (ZOL) and beta-ZOL were recovered at the duodenum beside the parent toxin ZON. Their recovery as a percentage of ZON-intake ranged between 43% and 132%. In conclusion, feeding of Fusarium toxin-contaminated wheat altered the ruminal protein utilization. The question of whether this effect was a result of the mycotoxin being present in the rumen or of Fusarium growth-related structural (cell wall) changes of the wheat grain needs to be clarified. The low recovery of DON at the duodenum would indicate either a nearly complete degradation of the molecule in the rumen or an absorption by the mucosa of the rumen, whereas the higher ZON recovery would suggest a lower degradation of the parent toxin in the rumen and/or recovery of some bile-originating entero-hepatic cycling ZON/metabolites.

Animal Feed↗
PubMed2005

Wheat cytogenetics in the genomics era and its relevance to breeding.

Hexaploid wheat is a species that has been subjected to most extensive cytogenetic studies. This has contributed to understanding the mechanism of the evolution of polyploids involving diploidization through genetic restriction of chromosome pairing to only homologous chromosomes. The availability of a variety of aneuploids and the ph mutants (Ph1 and Ph2) in bread wheat also allowed chromosome manipulations leading to the development of alien addition/substitution lines and the introgression of alien chromosome segments into the wheat genome. More recently in the genomics era, molecular tools have been used extensively not only for the construction of molecular maps, but also for identification/isolation of genes/QTLs (including epistatic QTLs, eQTLs and PQLs) for several agronomic traits. It has also been possible to identify gene-rich regions and recombination hot spots in the wheat genome, which are now being subjected to sequencing at the genome level, through development of BAC libraries. In the EST database also, among all plants wheat ESTs are the highest in number, and are only next to those for human, mouse, Ciona intestinalis (a chordate), rat and zebrafish genomes. These ESTs and sequences of several genomic regions have been subjected to a variety of applications including development of perfect markers and establishment of microcollinearity. The technique of in situ hybridization (including FISH, GISH and McFISH) and the development of deletion stocks also facilitated the preparation of physical maps. Molecular markers are also used for marker-assisted selection in wheat breeding programs in several countries. Construction of a wheat DNA chip, which will also become available soon, may further facilitate wheat genomics research. These enormous resources, knowledge base and the fast development of additional molecular tools and high throughput approaches for genotyping will prove extremely useful in future wheat research and will lead to development of improved wheat cultivars.

Agriculture↗
PubMed1997

Differentiation between cosensitization and cross-reactivity in wheat flour and grass pollen-sensitized subjects.

BACKGROUND: To diagnose baker's asthma, occupational sensitization to wheat flour should be distinguished clearly from influences of cosensitization such as it may exist in pollinosis patients. To define the route of sensitization, the cross-reactivity between wheat flour and grass pollen allergens was investigated. METHODS: Two groups of atopic individuals with or without professional contact to wheat flour were screened by skin prick test for their sensitization to wheat flour and grass pollen and, in the case of hints for cosensitization, by Enzyme Allergo Sorbent Test (EAST). Cross-reactivity between wheat flour and grass pollen allergens was investigated by IgE binding inhibition assay using sera of 20 cosensitized individuals and by immunoblots. RESULTS: The immunological cross-inhibition between wheat flour and grass pollen proves some proteins to share common allergenic determinants. Significant differences between bakers and individuals not occupationally exposed to flour could be seen in the inhibition of IgE binding to wheat flour. While the IgE binding to wheat flour allergens was only slightly inhibited by grass pollen proteins in baker's sera its inhibition was nearly complete by this extract in sera of nonexposed atopics. Immunoblots indicate that wheat proteins with a molecular weight of about 8-12 and 22 kD preferentially react with sensitized bakers' IgE and not with IgE of other individuals. IgE binding to grass pollen allergens in immunoblots and inhibition experiments showed no differences between bakers and other subjects. CONCLUSION: In the group of atopics without professional contact to flour, the positive test results from wheat flour obviously ensue from contact to cross-reacting grass pollen proteins whereas bakers are exposed and sensitized to allergens of both sources. Such cross-inhibition experiments help to identify the source of sensitization which may be difficult to obtain in case of cross-reacting allergens.

Asthma↗
PubMed2006

Alpha-gliadin genes from the A, B, and D genomes of wheat contain different sets of celiac disease epitopes.

BACKGROUND: Bread wheat (Triticum aestivum) is an important staple food. However, wheat gluten proteins cause celiac disease (CD) in 0.5 to 1% of the general population. Among these proteins, the alpha-gliadins contain several peptides that are associated to the disease. RESULTS: We obtained 230 distinct alpha-gliadin gene sequences from severaldiploid wheat species representing the ancestral A, B, and D genomes of the hexaploid bread wheat. The large majority of these sequences (87%) contained an internal stop codon. All alpha-gliadin sequences could be distinguished according to the genome of origin on the basis of sequence similarity, of the average length of the polyglutamine repeats, and of the differences in the presence of four peptides that have been identified as T cell stimulatory epitopes in CD patients through binding to HLA-DQ2/8. By sequence similarity, alpha-gliadins from the public database of hexaploid T. aestivum could be assigned directly to chromosome 6A, 6B, or 6D. T. monococcum (A genome) sequences, as well as those from chromosome 6A of bread wheat, almost invariably contained epitope glia-alpha9 and glia-alpha20, but never the intact epitopes glia-alpha and glia-alpha2. A number of sequences from T. speltoides, as well as a number of sequences fromchromosome 6B of bread wheat, did not contain any of the four T cell epitopes screened for. The sequences from T. tauschii (D genome), as well as those from chromosome 6D of bread wheat, were found to contain all of these T cell epitopes in variable combinations per gene. The differences in epitope composition resulted mainly from point mutations. These substitutions appeared to be genome specific. CONCLUSION: Our analysis shows that alpha-gliadin sequences from the three genomes of bread wheat form distinct groups. The four known T cell stimulatory epitopes are distributed non-randomly across the sequences, indicating that the three genomes contribute differently to epitope content. A systematic analysis of all known epitopes in gliadins and glutenins will lead to better understanding of the differences in toxicity among wheat varieties. On the basis of such insight, breeding strategies can be designed to generate less toxic varieties of wheat which may be tolerated by at least part of the CD patient population.

Amino Acid Sequence↗
PubMed2006

Biotypic variation among north American Russian wheat aphid (Homoptera: Aphididae) populations.

The Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera: Aphididae), has been a major economic pest of small grains in the western United States since its introduction in 1986. Recently, a new Russian wheat aphid biotype was discovered in southeastern Colorado that damaged previously resistant wheat, Triticum aestivum L. Biotype development jeopardizes the durability of plant resistance, which has been a cornerstone for Russian wheat aphid management. Our objective was to assess the relative amount of biotypic diversity among Russian wheat aphid populations collected from cultivated wheat and barley, Hordeum vulgare L. We conducted field surveys from May through June 2002 and August 2003 from seven counties within Texas, Kansas, Nebraska, and Wyoming. Based upon a foliar chlorosis damage rating, three new Russian wheat aphid biotypes were identified, one of which was virulent to all characterized sources of Russian wheat aphid resistance. The future success of Russian wheat aphid resistance breeding programs will depend upon the continual monitoring of extant biotypic diversity and determination of the ecological and genetic factors underlying the development of Russian wheat aphid biotypes.

Animals↗
PubMed2001

Ileal digestibilities of neutral detergent fiber, crude protein, and amino acids associated with neutral detergent fiber in wheat shorts for growing pigs.

An experiment was carried out to determine the ileal digestibility values of NDF, CP, and AA associated with NDF in different samples of wheat shorts consisting of different proportions of wheat bran, shorts, and flour, hereafter referred to as wheat fractions. Six barrows (average initial BW 37.2 kg, and fitted with a simple T-cannula at the distal ileum) were fed one of six experimental diets, formulated to contain 17% CP (as-fed basis), according to a 6 x 6 Latin square design. Diets A, B, C, D, and E contained 17.53% soybean meal (SBM), which contributed 50% CP to these diets. The diets contained shorts, bran, or flour alone or in combination, contributing the remaining 50% CP to these diets. The proportions of shorts, bran, and flour in the wheat fractions were 70% shorts and 30% bran in diet A, 85% shorts and 15% bran in diet B, 100% shorts in diet C, 85% shorts and 15% flour in diet D, and 70% shorts and 30% flour in diet E. Diet F contained 35.05% soybean meal, which provided the sole source of dietary CP. Chromic oxide was used as a digestibility marker. During the first experimental period, the daily dietary allowance was provided at a rate of 5% (wt/wt) of the average BW. Thereafter, the allowance was increased by 100 g at each successive period. Each experimental period comprised 12 d. Following a 7-d adaptation period, feces were collected for 48 h and ileal digesta for a total of 24 h. The contribution of CP and AA associated with NDF gradually decreased from wheat fraction A to E, reflecting a decrease in NDF content from 42.3 to 29.5%. Of the indispensable AA in wheat fraction A, the contributions ranged from 12.9 to 15.9%. In wheat fraction E, these values ranged from 9.0 to 11.3%. The ileal digestibility values of NDF ranged from 11.8% in diet E to 17.1% in diet C (P > 0.05). There were usually no differences (P > 0.05) in the ileal digestibilities of AA associated with NDF between the wheat fractions. However, with the exception of lysine and tyrosine, there were negative correlations (P < 0.05) between the apparent ileal AA digestibilities and the content (%) of CP associated with NDF in the wheat fractions. Furthermore, there was no effect (P > 0.05) of the diets containing wheat fractions on the recovery of bacterial protein and mucin in ileal digesta.

Amino Acids↗
PubMed2005

[Effect of acid rain on seed germination of rice, wheat and rape].

Rice, wheat and rape seeds were treated with simulated acid rain at pH 2.0, 2.5, 3.0, 3.5, 4.0 and 5.0 levels for 7 days in order to understand the effects of acid rain on seed germination of various acid-fast plant. The germination test showed that seed germination was absolutely inhibited at pH 2.0 for three species. Rice and wheat seeds germinated abnormally at pH 2.5. WhenpH values above 3.0, percentage germination, germination energy, germination index, vigor index of rice, wheat and rape seeds increased in relation with decreased acidity levels. In contrast, the percentage of abnormal germination of rice and wheat decreased. The experiment data about physiological aspect demonstrated that water absorption rate, respiratory rate and storage reserve transformation rate of rice, wheat and rape seeds also increased with increased pH values. The storage loss of rice and wheat increased with increased pH values but that of rape decreased. Inhibition index of shoot and root length of three kinds of seeds decreased in relation with increased pH values. The amplitude difference of index of rice was lower than that of wheat, and wheat was lower than that of rape. The experiment data showed that rice had stronger fastness than wheat and rape, wheat had stronger fastness than rape under acid rain stress.

Acid Rain↗
PubMed2004

[Asymmetric somatic hybridization between mixed wheat and Psathyrostachys juncea].

Psathyrostachys juncea is a potential source of useful genes, such as the barley yellow dwarf virus resistance, salt tolerance and drought tolerance, for wheat improvement. Conventional sexual hybridization between wheat and Psathyrostachys juncea is very difficult to occur as the two are sexual incompatible. Somatic hybridization is a promising technique for creating hybrids across the sexual border. Here we report a fusion system for somatic hybridization of wheat using PEG method. Mixed protoplasts of two wheat (Triticum aestivum L. cv. Jinan 177) culture cells (cha9 and 176) were used as the recipients to fuse with the donors, the protoplasts of Psathyrostachys juncea (Fisch.) Nevski irradiated with ultraviolet light (UV) at an intensity of 380 microW/cm2 for 1 min or 2 min. Sixteen clones were generated in the combination I, (wheat 176 + wheat cha9 + P. juncea 1 min UV treatment) and five of the hybrid clones could differentiate to green plants. All the regenerated clones were confirmed as somatic hybrids by cytological, isozyme, chromosome and random amplified polymorphic DNA (RAPD) analysis. Chloroplast genome of the hybrids was analyzed using 7 pairs of wheat-specific chloroplast microsatellite (SSR) primers. Three clones were obtained from the combination II (wheat 176 + wheat cha9 + P. juncea 2 min UV treatment), and all browned slowly and died in 3 months. This result indicated that the mixed wheat cells was helpful to the formation and regeneration of hybrid callus and the dosage of the UV had significant effect on the development of the fusion products.

Chromosomes, Plant↗