SEARCH · PubMed Health

Results for “BARLEY”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

PubMed2002

Effects of barley yellow mosaic disease resistant gene rym1 on the infection by strains of Barley yellow mosaic virus and Barley mild mosaic virus.

Although a Chinese landrace of barley, Mokusekko 3, is completely resistant to all strains of Barley yellow mosaic virus (BaYMV) and Barley mild mosaic virus (BaMMV), and is known to have at least two resistant genes, rym1 and rym5, only rym5 has been utilized for BaYMV resistant barley breeding in Japan. In order to clarify the effect of rym1 on BaYMV and BaMMV, and to utilize the gene for resistant barley breeding, the susceptibilities of only rym1 carrying breeding lines against BaYMV and BaMMV were investigated. In the assessment of resistance to BaYMV-I, 341 F(2) populations derived from a cross between the resistant line Y4 with only rym1 and the susceptible cv Haruna Nijo shows that the segregation loosely fits a 1R:3S ratio (0.05 > P > 0.01), suggesting that the resistance is controlled by a single recessive gene, rym1. Further, none of the F(3) lines derived from the nine resistant F(2) plants showed any disease symptoms in the field infected by BaYMV-I. The same nine F(3) lines showed almost the same agronomic characters in the field infected by BaYMV-III as those in the uninfected field, apart from the symptom of showing numerous mosaics. This result indicates that the gene rym1 has an acceptable level of resistance to BaYMV-III. In the assessment of resistance to BaYMV-II, BaMMV-Ka1 and -Na1, an artificial infection method was adopted and the susceptibilities to those viruses were investigated. Although the control varieties, Ko A and Haruna Nijo, were infected with all of them, the rym1 gene carrying BC(2)F(3) lines were completely resistant to all strains. In summary, rym1 is completely resistant to BaYMV-I, -II, BaMMV-Ka1 and -Na1, and has an acceptable level of resistance to BaYMV-III. This study concludes with a discussion of the reason why the important resistance gene rym1 was eliminated along with resistant cultivars during breeding for resistance to BaYMV.

Genes, Plant↗

PubMed1996

The 5S rRNA gene units in ancestral two-rowed barley (Hordeum spontaneum C. Koch) and bulbous barley (H. bulbosum L.): sequence analysis and phylogenetic relationships with the 5S rDNA units of cultivated barley (H. vulgare L.).

5S rRNA genes from several accessions of Hordeum spontaneum and Hordeum bulbosum, wild relatives of cultivated barley, Hordeum vulgare, have been amplified by the polymerase chain reaction, cloned, and sequenced. Evaluation of aligned sequences along with principal coordinate analysis demonstrates that the two classes of 5S rDNA sequences found in cultivated barley, and subclasses (groups) of these sequences, can also be found in its closest wild relatives. The two classes of units, formerly categorized as containing short or long 5S rDNA repeats, are distinguishable by the presence or absence of a TAG repeating unit. Sequence comparisons of individual clones (units) isolated from different species have allowed us to confirm that orthology exists for several groups. This demonstration of orthologous groups suggests that the 5S rDNA sequence may be useful for further phylogenetic analysis in the genus Hordeum and possibly in the Triticeae.

Base Sequence↗

PubMed1997

The effects of amount of whole barley, barley bulk density, and form of roughage on feedlot lamb performance, carcass characteristics, and digesta kinetics.

We conducted two feedlot trials and one metabolism trial to evaluate the effect of barley level, barley bulk density, and physical form of roughage on lamb growth performance and digesta kinetics. Level of whole barley (50, 70, 90%) and type of roughage (chopped or pelleted alfalfa) were evaluated in Trial 1 (50 d period). Trial 2 (50 d) evaluated barley bulk density (heavy = 671 and light = 607 kg/m3), form of roughage (pelleted or chopped alfalfa), and level of barley (80 or 40%). The influence of treatments used in Trial 2 on digesta kinetics was evaluated in Trial 3. Gain:feed increased and DMI decreased (P < .10) linearly with increasing level of barley, and ADG and DMI were greater (P < . 10) for lambs fed pelleted vs chopped alfalfa in Trial 1. The 70% barley diet produced the highest yield grade and kidney-pelvic fat and the lowest leg score among barley levels (P < .10). Lambs fed pelleted alfalfa had heavier carcasses and a thicker body wall than lambs fed chopped alfalfa (P < .02). In Trial 2, DMI was less and gain:feed greater (P < .01) for lambs fed the heavy barley than for lambs fed the light barley and for the 80% barley diet compared to the 40% barley diet. Lambs fed pelleted alfalfa had greater dressing percentages than lambs fed chopped alfalfa. Backfat and body wall thickness were greater (P < .10) for lambs fed the 80% barley diet than for those fed the 40% barley diet. In Trial 3, retention time of barley was greater (P < .10) for lambs fed light rather than heavy barley, and retention time of alfalfa was greater (P < .10) for lambs fed chopped compared with pelleted alfalfa. Acetate:propionate ratio was greater (P < .10) for lambs fed light vs heavy barley and lambs fed the 40 vs 80% barley diets. Ruminal pH was lower (P = .05) and in situ barley digestion greater (P = .03) over time in lambs fed the 80% barley diet than in lambs fed the 40% barley diet. Feedlot lamb ADG was not always greatest with high levels of barley; however, gain:feed improved at the higher barley levels. The higher barley levels seemed to result in fatter lambs.

Animal Feed↗

PubMed2000

Barley allele-specific amplicons useful for identifying wheat-barley recombinant chromosomes.

Barley (Hordeum vulgare L.) is potentially a new source of genes for wheat (Triticum aestivum L.) improvement. Wheat-barley chromosome recombinant lines provide a means for introgressing barley genes to wheat genome by chromosome engineering, and since these are expected to occur only rarely in special cytogenetic stocks, an efficient selection skill is necessary to identify them. To convert RFLP markers to barley allele-specific PCR markers useful for effective production of wheat-barley recombinant lines, 91 primer sets derived from RFLP clones which were previously mapped to the barley chromosomes were examined for PCR amplification using 'Chinese Spring' wheat, 'Betzes' barley and the wheat-barley chromosome addition lines. The polymorphisms were detected by an agarose gel electrophoresis of the PCR products without digestion with restriction enzymes. Out of 81 primer sets producing polymorphisms between the wheat and barley genomes, 26 amplified barley chromosome-specific DNAs which were confirmed to be located on the same chromosome as the RFLP markers by using the wheat-barley chromosome addition lines. These amplified DNAs represent barley allele-specific amplicons, which distinguish barley alleles from their wheat homoeologous counterparts. The present investigation revealed a higher probability for obtaining allele-specific amplicons from genomic DNA-derived RFLP markers than from cDNA-derived ones. The barley allele-specific amplicons developed in this study, namely, four for chromosome 2H, two for 3H, seven for 4H, eight for 5H, one for 6H and four for 7H, are suitable for identifying 'Chinese Spring' wheat- 'Betzes' barley recombinant chromosomes. However, one out of eight barley allele-specific amplicons on chromosome 5H did not detect a unique barley band in a 'New Golden' barley chromosome 5H addition line of 'Shinchunaga' wheat, indicating there may be a need to reconstruct allele-specific amplicons with different barley cultivars.

Alleles↗

PubMed1998

Eating barley too frequently or in excess decreases lambs' preference for barley but sodium bicarbonate and lasalocid attenuate the response.

We conducted experiments to determine whether preference for barley was affected when lambs ate various amounts of barley and whether lambs ate more barley when it contained lasalocid and sodium bicarbonate (NaHCO3), both of which attenuate acidosis. In Exp. 1, lambs were assigned to two treatments (six lambs/treatment). For 2 d, lambs in two treatments were offered either 400 or 1,200 g of rolled barley from 0600 to 0700 as a preload meal. A preference ratio [PR = barley ingested/(total amount of alfalfa + barley ingested)] was calculated based on lambs' intake when offered a choice of 200 g each of rolled barley and alfalfa pellets hourly from 0700 to 1100. After the preload meal, lambs in Treatment 1 (400 g preload) showed equal preference for barley (.52) and alfalfa (.48) for 4 h on d 1 (P > .05); their preference for barley was less after the meal of barley on d 1 (.52) than on d 2 (.72), but their preference for barley declined between h 3 (.81) and 4 (.55) of d 2 (P = .11). Lambs in Treatment 2 (1,200 g preload) showed a low preference for barley on d 1 (.29) and 2 (.19) (P < .001). In Exp. 2, lambs were assigned to four treatments (six lambs/treatment): 1) rolled barley + NaHCO3 (2%) + lasalocid (33 ppm); 2) rolled barley + NaHCO3 (2%); 3) rolled barley + lasalocid (33 ppm); or 4) rolled barley. Intake of barley by lambs offered NaHCO3 + lasalocid (Treatment 1) was greater (P = .07) than that by lambs offered NaHCO3 (Treatment 2), whereas intake by lambs offered lasalocid (Treatment 3) was similar (P > .05) to that by controls. We conclude that eating barley too frequently or in excess caused a decrease in lambs' preference for barley and that NaHCO3 and lasalocid attenuated the aversion.

Acidosis, Lactic↗

PubMed1997

Comparison of barley, hull-less barley, and corn in the concentrate of dairy cows.

Twelve multiparous and 12 primiparous lactating Holstein cows were used to compare the effects of hull-less barley with barley and corn on dry matter intake (DMI), digestibility, and milk production. Three concentrates were formulated using steam-rolled grains: barley, hull-less barley, or corn. During three 21-d periods, cows received a total mixed diet consisting of 60% concentrate, 30% barley silage, and 10% cubed alfalfa hay [dry matter (DM) basis]. Milk production and DMI were higher for cows fed the corn diet than for cows fed the barley or hull-less barley diets; no interaction with parity was detected. The DMI of cows fed the hull-less barley and barley diets were similar. Despite the higher estimated energy density of the hull-less barley diet, milk production was similar for cows fed the hull-less barley and barley diets because of the lower digestibility of the hull-less barley. Results of an in situ study showed that, for steam-rolled grains, DM and starch from hull-less barley were less degradable than were DM and starch from barley, although the opposite result was observed for ground grains. For steam-rolled hull-less barley, low ruminal degradabilities of DM and starch were apparently not compensated by high intestinal digestibility because total tract digestibility and milk production were lower than expected. Although the net energy for lactation value of hull-less barley is higher than that for barley, milk production by cows might be limited unless hull-less barley is adequately processed to ensure high ruminal and total tract digestibilities.

Animal Feed↗

PubMed2003

Effects of moisture, roller setting, and saponin-based surfactant on barley processing, ruminal degradation of barley, and growth performance by feedlot steers.

Two experiments were conducted to study the effects of six processing techniques for barley grain in a 3 x 2 factorial arrangement of grain conditions and roller settings on ruminal degradation of the grain (Exp. 1) and on growth performance by 138 feedlot steers (n = 23 per treatment; Exp. 2). Dry barley (11% moisture, D barley), barley tempered to 20% moisture (M barley), and barley tempered with 60 mL/t of surfactant-based tempering agent (GrainPrep, Agrichem, Inc., Anoka, MN; MS barley), were each rolled at two roller settings selected from preliminary tests. The settings selected for the study were RD, the roller position that had yielded optimally processed D barley, and RMS, the setting that had yielded optimally processed MS barley. Setting RMS was tighter than RD. Barley rolled at the RMS setting was more extensively processed (i.e., had a lower [P < 0.001] processing index, PI), had lighter (P < 0.001) volume weight, thinner (P < 0.001) kernels, and fewer (P < 0.001) whole kernels compared with setting RD. Tempering did not affect (P > 0.05) PI, percentage of whole kernels, or kernel thickness at either roller setting. The processing characteristics of tempered barley were unaffected (P > 0.05) by surfactant. The extent of in situ DM disappearance (ISDMD) was higher (P < 0.01) in grain rolled at setting RMS compared with RD. At both roller settings, tempering reduced (P < 0.05) ISDMD between 4 and 24 h of ruminal incubation. Steers fed RMS-rolled barley had lower (P < 0.001) DMI, slightly lower (P = 0.084) ADG, but increased (P < 0.05) gain:feed (G:F) compared with steers fed RD-rolled barley. Tempering did not affect (P > 0.05) ADG, DMI, or G:F during backgrounding, but improved (P < 0.01) these variables during finishing. Surfactant improved (P < 0.05) G:F but not DMI or ADG. The improvement in G:F was most pronounced when setting RMS was used. The optimal PI values calculated from performance data were numerically greater for the backgrounding diet than for the finishing diet. Steers fed M or MS barley had heavier (P < 0.01) hot carcasses and thicker (P < 0.05) fat cover but lower (P < 0.05) dressing percentages than steers fed D. When the feed barley was rolled at setting RMS, steers fed MS barley produced heavier (P < 0.05) carcasses than those fed M. Tempering with or without surfactant increased performance by feedlot steers compared with not tempering. Diet composition and degree of barley processing mediated this effect.

Animal Feed↗

PubMed1997

Comparison of hull-less barley, barley, or corn for lactating cows: effects on extent of digestion and milk production.

Six lactating, cannulated Holstein cows were used in a double 3 x 3 Latin square design to compare the effects of hull-less barley with barley and corn on ruminal fermentation, rate of passage, flow of nutrients to the duodenum, and milk production. Diets consisted of 60% concentrate, 30% barley silage, and 10% alfalfa hay (dry matter basis). Concentrates contained steam-rolled grains: hull-less barley, barley, or corn. Dry matter intake was unaffected by grain source, but starch intake tended to be greatest when hull-less barley or corn was fed. The barley diet was more degradable in the rumen than was the hull-less barley or corn diet, and, therefore, flow of microbial organic matter to the duodenum was greatest for cows fed the barley diet. Flow of microbial N to the duodenum was greater (50 g/d) for cows fed the barley diet than for cows fed the other diets, and the flow of ruminally undegradable N was greater (43 and 28 g/d) for cows fed the hull-less barley and corn diets, respectively, than for cows fed the barley diet. As a result, flow of nonammonia N to the duodenum was unaffected by grain source. Total tract apparent digestibility was highest for cows fed the barley and corn diets. Despite its low digestibility, cows fed the hull-less barley diet produced a similar amount of milk as did cows fed the barley and corn diets. Further studies are needed to evaluate the effects of processing hull-less barley on its utilization by dairy cows.

Animal Feed↗

PubMed2007

Molecular chemical structure of barley proteins revealed by ultra-spatially resolved synchrotron light sourced FTIR microspectroscopy: comparison of barley varieties.

Barley protein structure affects the barley quality, fermentation, and degradation behavior in both humans and animals among other factors such as protein matrix. Publications show various biological differences among barley varieties such as Valier and Harrington, which have significantly different degradation behaviors. The objectives of this study were to reveal the molecular structure of barley protein, comparing various varieties (Dolly, Valier, Harrington, LP955, AC Metcalfe, and Sisler), and quantify protein structure profiles using Gaussian and Lorentzian methods of multi-component peak modeling by using the ultra-spatially resolved synchrotron light sourced Fourier transform infrared microspectroscopy (SFTIRM). The items of the protein molecular structure revealed included protein structure alpha-helices, beta-sheets, and others such as beta-turns and random coils. The experiment was performed at the National Synchrotron Light Source in Brookhaven National Laboratory (BNL, US Department of Energy, NY). The results showed that with the SFTIRM, the molecular structure of barley protein could be revealed. Barley protein structures exhibited significant differences among the varieties in terms of proportion and ratio of model-fitted alpha-helices, beta-sheets, and others. By using multi-component peaks modeling at protein amide I region of 1710-1576 cm-1, the results show that barley protein consisted of approximately 18-34% of alpha-helices, 14-25% of beta-sheets, and 44-69% others. AC Metcalfe, Sisler, and LP955 consisted of higher (P<0.05) proportions of alpha-helices (30-34%) than Dolly and Valier (alpha-helices 18-23%). Harrington was in between which was 25%. For protein beta-sheets, AC Metcalfe, and LP955 consisted of higher proportions (22-25%) than Dolly and Valier (13-17%). Different barley varieties contained different alpha-helix to beta-sheet ratios, ranging from 1.4 to 2.0, although the difference were insignificant (P>0.05). The ratio of alpha-helices to others (0.3 to 1.0, P<0.05) and that of beta-sheets to others (0.2 to 0.8, P<0.05) were different among the barley varieties. It needs to be pointed out that using a multi-peak modeling for protein structure analysis is only for making relative estimates and not exact determinations and only for the comparison purpose between varieties. The principal component analysis showed that protein amide I Fourier self-deconvolution spectra were different among the barley varieties, indicating that protein internal molecular structure differed. The above results demonstrate the potential of the SFTIRM to localize relatively pure protein areas in barley tissues and reveal protein molecular structure. The results indicated relative differences in protein structures among the barley varieties, which may partly explain the biological differences among the barley varieties. Further study is needed to understand the relationship between barley molecular chemical structure and biological features in terms of nutrient availability and digestive behavior.

Hordeum↗

PubMed1995

Effect of barley variety and dietary barley content on digestive function in beef steers fed grass hay-based diets.

Five ruminally and duodenally cannulated steers were used in a 5 x 5 Latin square design with a 2 x 2 + 1 arrangement of treatments to study the effects of barley variety and dietary barley content on digestive function in steers fed grass hay-based diets. Barley varities evaluated were Russell and Steptoe, which had bulk densities of 67.7 and 64.5 kg/hL, respectively. Supplemental treatments were as follows: corn, low Russell (Ru-lo), low Steptoe (St-lo), high Russell (Ru-hi), and high Steptoe (St-hi). Corn, Ru-lo, and St-lo were provided at 30% (DM basis) of grass hay-based diets, whereas Ru-hi and St-hi were provided at 35.5% of diet DM (equal starch content as the corn treatment). No treatment differences (P > .10) were observed for DMI, ruminal particulate passage rate, and NDF total tract digestibility. Ruminal DM and starch digestibility were greater (P < .01) for barley-containing diets than for the corn diet. Similarly, total tract DM (P < .10) and starch (P < .01) digestibility was greater for barley than for corn diets. Microbial protein and non-NH3 N flow to the small intestine were greater (P < .01) for the barley diets than for the corn diet. Starch intake (P < .01) and DM digestibility (P < .10) were greater for high- than for low-barley diets; however, differences due to barley variety were not observed (P > .10). In situ disappearance of grass hay NDF at 8 and 96 h of incubation was greater (P < .05) for barley than for corn diets. Rate of in situ disappearance of grain DM was greater (P < .01) for barley than for corn and for Russell than for Steptoe barley. Responses suggest that ruminal and total tract digestibility and protein flow to the small intestine can be increased with barley compared with corn as an energy supplement to grass hay-based diets.

Animals↗

PubMed2005

Transcriptional regulation of the sbeIIb genes in sorghum (Sorghum bicolor) and barley (Hordeum vulgare): importance of the barley sbeIIb second intron.

The transcriptional activity of the sorghum sbeIIb gene, encoding starch branching enzyme IIb, is seed specific, with expression in both the endosperm and the embryo. In comparison, expression of barley sbeIIb is confined to the endosperm, whereas that of barley sbeIIa occurs in endosperm, embryonic and vegetative tissues. It has been suggested that the second intron of barley sbeIIb may be instrumental in conferring endosperm-specific expression. Therefore, to further investigate the regulatory mechanisms of barley and sorghum sbe, we examined the tissue-specific activity of the sorghum sbe promoter in transient assays of green fluorescent protein (gfp) reporter constructs. We found that, when linked to the barley sbeIIb second intron, the sorghum sbeIIb promoter could not drive gfp transcription in sorghum or barley embryonic cells. Similar results were obtained for the barley sbeIIa promoter. Database searches showed that sequences homologous to the barley sbeIIb intron also exist in introns and flanking regions of some other grass genes. Deletion mutagenesis of the sorghum sbeIIb promoter identified the minimal promoters required for high- and low-level expression, respectively, but did not reveal any putative promoter elements crucial for expression. A sequence with similarity to the SURE element, implicated in sugar signaling, was located in the distal promoter region of sorghum sbeIIb, upstream of the minimal promoters. SURE elements are present in the proximal promoter regions of the sugar-regulated barley iso1 gene, and barley sbeIIb. In keeping in line with these observations, RNA-gel blot analyses demonstrated that expression of barley sbeIIb was sugar inducible, whereas that of sorghum sbeIIb was not.

1,4-alpha-Glucan Branching Enzyme↗

PubMed1994

Oat bran, barley and malted barley lower plasma cholesterol relative to wheat bran but differ in their effects on liver cholesterol in rats fed diets with and without cholesterol.

Males rats were fed diets containing wheat bran, oat bran, barley or malted barley without or with 10 g/kg cholesterol + 1 g/kg cholic acid (referred to as "cholesterol"). Plasma total, HDL, and VLDL+LDL cholesterol concentrations were higher overall in rats fed cholesterol. There was a significant interaction between dietary cholesterol and cereal type. Higher concentrations of total and VLDL+LDL cholesterol were found in rats fed cholesterol with wheat bran than in those fed oat bran, barley or malted barley. HDL cholesterol concentrations were higher overall in rats fed wheat bran than in those fed oat bran or barley but not malted barley. Liver cholesterol pools were higher overall in rats fed cholesterol. In all animals fed oat bran, liver cholesterol was lower than in rats fed barley or malted barley. Hepatic HDL receptor activity was lower overall in rats fed cholesterol. There was no independent effect of cereal type on HDL receptor activity, but there was a significant interaction with dietary cholesterol. Activity tended to be higher in rats fed malted barley with cholesterol than in rats fed malted barley without cholesterol. LDL receptor activity was not affected by cereal type but was significantly lower overall in rats fed cholesterol.

Animals↗

PubMed1996

Products based on a high fiber barley genotype, but not on common barley or oats, lower postprandial glucose and insulin responses in healthy humans.

Postprandial blood glucose and insulin responses to cereal products made from common barley, oats or a barley genotype containing elevated levels of beta-glucans were evaluated in nine healthy subjects. Porridges were made from commercial Swedish whole-meal barley or oat flours, and a mixed whole-meal porridge using the high fiber barley genotype and commercial Swedish common barley (50:50). Also studied were two types of flour-based bread products composed of high fiber barley and common barley in ratios of 50:50 or 80:20, respectively. The common oat and barley porridges produced postprandial glucose and insulin responses similar to the white wheat bread reference, suggesting that the naturally occurring dietary fiber in these whole-meal flours has no impact on the glucose tolerance. In contrast, all high fiber barley products induced significantly lower responses than did the reference product, with the glycemic and insulin indices ranging from 57 to 72 or 42 to 72%, respectively. It is concluded that "lente" products of high sensory quality can be prepared from a barley genotype with an elevated content of soluble dietary fiber. The glycemic index of these products compares favorably with that of products made from common cereals, suggesting their use as a potential component of diets for patients with diabetes and hyperlipidemia, and for individuals predisposed to metabolic disease.

Adult↗

PubMed2005

Transcriptome analysis and physical mapping of barley genes in wheat-barley chromosome addition lines.

Wheat-barley chromosome addition lines are useful genetic resources for a variety of studies. In this study, transcript accumulation patterns in Betzes barley, Chinese Spring wheat, and Chinese Spring-Betzes chromosome addition lines were examined with the Barley1 Affymetrix GeneChip probe array. Of the 4014 transcripts detected in Betzes but not in Chinese Spring, 365, 271, 265, 323, 194, and 369 were detected in wheat-barley disomic chromosome addition lines 2(2H), 3(3H), 4(4H), 7(5H), 6(6H), and 1(7H), respectively. Thus, 1787 barley transcripts were detected in a wheat genetic background and, by virtue of the addition line in which they were detected, were physically mapped to barley chromosomes. We validated and extended our approach to physically map barley genes to the long and short arms of chromosome 6(6H). Our physical map data exhibited a high level of synteny with homologous sequences on the wheat and/or rice syntenous chromosomes, indicating that our barley physical maps are robust. Our results show that barley transcript detection in wheat-barley chromosome addition lines is an efficient approach for large-scale physical mapping of genes.

Chromosomes, Plant↗

PubMed2005

High-resolution mapping of the barley leaf rust resistance gene Rph5 using barley expressed sequence tags (ESTs) and synteny with rice.

The rapidly growing expressed sequence tag (EST) resources of species representing the Poacea family and availability of comprehensive sequence information for the rice (Oryza sativa) genome create an excellent opportunity for comparative genome analysis. Extensive synteny between rice chromosome 1 and barley (Hordeum vulgare L.) chromosome 3 has proven extremely useful for saturation mapping of chromosomal regions containing target genes of large-genome barley with conserved orthologous genes from the syntenic regions of the rice genome. Rph5 is a gene conferring resistance to the barley leaf rust pathogen Puccinia hordei. It was mapped to chromosome 3HS, which is syntenic with rice chromosome 1S. The objective of this study was to increase marker density within the sub-centimorgan region around Rph5, using sequence-tagged site (STS) markers that were developed based on barley ESTs syntenic to the phage (P1)-derived artificial chromosome (PAC) clones comprising the distal region of rice chromosome 1S. Five rice PAC clones were used as queries in a blastn search to screen 375,187 barley ESTs. Ninety-four non-redundant EST sequences were identified from the EST database and used as templates to design 174 pairs of primer combinations. As a result, 9 barley EST-based STS markers were incorporated into the 'Bowman' x 'Magnif 102' high-resolution map of the Rph5 region. More importantly, six markers, including five EST-derived STS sequences, were found to co-segregate with Rph5. The results of this study demonstrate the usefulness of rice genomic resources for efficient deployment of barley ESTs for marker saturation of targeted barley genomic regions.

Basidiomycota↗

PubMed2005

Reconstitution of cyanogenesis in barley (Hordeum vulgare L.) and its implications for resistance against the barley powdery mildew fungus.

Barley (Hordeum vulgare L.) produces a leucine-derived cyanogenic beta-D-glucoside, epiheterodendrin that accumulates specifically in leaf epidermis. Barley leaves are not cyanogenic, i.e. they do not possess the ability to release hydrogen cyanide, because they lack a cyanide releasing beta-D-glucosidase. Cyanogenesis was reconstituted in barley leaf epidermal cells through single cell expression of a cDNA encoding dhurrinase-2, a cyanogenic beta-D-glucosidase from sorghum. This resulted in a 35-60% reduction in colonization rate by an obligate parasite Blumeria graminis f. sp. hordei, the causal agent of barley powdery mildew. A database search for barley homologues of dhurrinase-2 identified a (1,4)-beta-D-glucan exohydrolase isozyme betaII that is located in the starchy endosperm of barley grain. The purified barley (1,4)-beta-D-glucan exohydrolase isozyme betaII was found to hydrolyze the cyanogenic beta-D-glucosides, epiheterodendrin and dhurrin. Molecular modelling of its active site based on the crystal structure of linamarase from white clover, demonstrated that the disposition of the catalytic active amino acid residues was structurally conserved. Epiheterodendrin stimulated appressoria and appressorial hook formation of B. graminis in vitro, suggesting that loss of cyanogenesis in barley leaves has enabled the fungus to utilize the presence of epiheterodendrin to facilitate host recognition and to establish infection.

Ascomycota↗

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↗

PubMed1997

Minimum versus optimum concentrations of fiber in dairy cow diets based on barley silage and concentrates of barley or corn.

Six primiparous and 6 multiparous lactating Holstein cows were used in a double d6 x 6 Latin square to determine the effects of the percentage of forage fiber in diets containing concentrates based on barley or corn. Cows received one of six diets that provided three percentages of neutral detergent fiber (NDF) from barley silage [19.5, 25.0, and 40.9% of dry matter intake (DMI)] combined with concentrates based on either barley or corn. The DMI (18.6 vs. 18.3 kg/d) and net energy for lactation (27.2 vs. 26.8 Mcal/d) were similar for cows fed barley and corn diets, respectively. Consequently, milk yield (25.7 vs. 25.0 kg/d) and fat-corrected milk yield (22.3 vs. 21.7 kg/d) were not affected by type of grain. Milk yields were similar for cows fed low and medium NDF diets, but yields declined when NDF from forage exceeded 25% of DMI because of declining intake of net energy for lactation. Effects of increased fiber from forage on milk fat content differed depending on diet; the low NDF diet based on barley caused milk fat to decline. Rumination time was higher for diets based on barley than for diets based on corn (516 vs. 469 min/d), and, as the percentage of forage fiber in the diet increased from low to high, rumination time increased more for cows fed diets based on corn than for cows fed diets based on barley. The minimum amount of forage fiber necessary in diets to avoid milk fat depression appeared to be higher for barley diets than for corn diets, although milk fat depression may not be a valid criterion by which to assess minimum fiber concentrations. Further research is needed to determine the minimum concentration of forage fiber needed to ensure healthy ruminal function and cow longevity.

Animal Nutritional Physiological Phenomena↗