Showing papers by "Agriculture and Agri-Food Canada published in 2001"
TL;DR: For different esters from the same vegetable oil, methyl esters were the most volatile, and the volatility decreased as the alkyl group grew bulkier, however, the bio-diesels were considerably less volatile than the conventional diesel fuels.
716 citations
TL;DR: Results of the first meta-analysis examining the relationship between intake of flaxseed or its components and risk reduction of disease in humans is presented and some areas of potential opportunities and impact of using flax Seed or its component in the diet are highlighted.
Abstract: Flaxseed is emerging as one of the key sources of phytochemicals in the functional food arena. In addition to being one of the richest sources of α-linolenic acid oil and lignans, flaxseed is an essential source of high-quality protein and soluble fibre and has considerable potential as a source of phenolic compounds. The implications of diets containing flaxseed or its components for human nutrition and disease prevention are analysed in this paper. Results of the first meta-analysis examining the relationship between intake of flaxseed or its components and risk reduction of disease in humans is presented. Some areas of potential opportunities and impact of using flaxseed or its components in the diet are highlighted. Les graines de lins sont une source de produits fonctionnels: outre leur richesse en acide α-linolenique et en lignanes, elles contiennet des proteines vegetales de haute qualite, des fibres solubles et de nombreux compose phenoliques. Les effets d'un regime alimentaire enrichi en graines de lins ou en ses composants est etudie ici, chez l'homme. les etudes epidemiologiques montrent un effet cardioprotecteur et anticarcinogene.
505 citations
TL;DR: Experimentation with new accurate tools provide useful information about the metabolism of tea components in the body, their mode of action as antioxidants at the cellular level and their protective role in the development of cancer, cardiovascular disease and other pathologies.
Abstract: Important progress has been made in the past five years concerning the effects of green and black tea on health. Experimentation with new accurate tools provide useful information about the metabolism of tea components in the body, their mode of action as antioxidants at the cellular level and their protective role in the development of cancer, cardiovascular disease and other pathologies. The use of tea components as nutraceuticals and functional foods are also discussed.
499 citations
TL;DR: In this paper, the emulsification properties of 14 hydrocolloid gums (propylene glycol alginate, gellan, carrageenan, pectin, methylcellulose, microcrystalline cellulose, gum arabic, locust bean gum, guar, xanthan, mustard, flaxseed, fenugreek, oat) were investigated.
472 citations
TL;DR: DNA markers for FHB resistance QTLs have been identified and may be used to speed the introgression of resistance genes into adapted germplasm and should be useful in marker-assisted selection.
Abstract: Genetic resistance to Fusarium head blight (FHB), caused by Fusarium graminearum, is necessary to reduce the wheat grain yield and quality losses caused by this disease. Development of resistant cultivars has been slowed by poorly adapted and incomplete resistance sources and confounding environmental effects that make screening of germplasm difficult. DNA markers for FHB resistance QTLs have been identified and may be used to speed the introgression of resistance genes into adapted germplasm. This study was conducted to identify and map additional DNA markers linked to genes controlling FHB resistance in two spring wheat recombinant inbred populations, both segregating for genes from the widely used resistance source ’Sumai 3’. The first population was from the cross of Sumai 3/Stoa in which we previously identified five resistance QTLs. The second population was from the cross of ND2603 (Sumai 3/Wheaton) (resistant)/ Butte 86 (moderately susceptible). Both populations were evaluated for reaction to inoculation with F. graminearum in two greenhouse experiments. A combination of 521 RFLP, AFLP, and SSR markers were mapped in the Sumai 3/Stoa population and all DNA markers associated with resistance were screened on the ND2603/Butte 86 population. Two new QTL on chromosomes 3AL and 6AS wer found in the ND2603/Butte 86 population, and AFLP and SSR markers were identified that explained a greater portion of the phenotypic variation compared to the previous RFLP markers. Both of the Sumai 3-derived QTL regions (on chromosomes 3BS, and 6BS) from the Sumai 3/Stoa population were associated with FHB resistance in the ND2603/Butte 86 population. Markers in the 3BS QTL region (Qfhs.ndsu-3BS) alone explain 41.6 and 24.8% of the resistance to FHB in the Sumai 3/Stoa and ND2603/Butte 86 populations, respectively. This region contains a major QTL for resistance to FHB and should be useful in marker-assisted selection.
466 citations
TL;DR: Structures suggest that the Ve genes encode a class of cell-surface glycoproteins with receptor-mediated endocytosis-like signals and leucine zipper or PEST sequences.
Abstract: In tomato, Ve is implicated in race-specific resistance to infection by Verticillium species causing crop disease. Characterization of the Ve locus involved positional cloning and isolation of two closely linked inverted genes. Expression of individual Ve genes in susceptible potato plants conferred resistance to an aggressive race 1 isolate of Verticillium albo-atrum. The deduced primary structure of Ve1 and Ve2 included a hydrophobic N-terminal signal peptide, leucine-rich repeats containing 28 or 35 potential glycosylation sites, a hydrophobic membrane-spanning domain, and a C-terminal domain with the mammalian E/DXXXLphi or YXXphi endocytosis signals (phi is an amino acid with a hydrophobic side chain). A leucine zipper-like sequence occurs in the hydrophobic N-terminal signal peptide of Ve1 and a Pro-Glu-Ser-Thr (PEST)-like sequence resides in the C-terminal domain of Ve2. These structures suggest that the Ve genes encode a class of cell-surface glycoproteins with receptor-mediated endocytosis-like signals and leucine zipper or PEST sequences.
463 citations
TL;DR: In this paper, rheological properties of several food hydrocolloids (carrageenan, pectin, gelatin, starch and xanthan) were evaluated using a rotational viscometer at three concentrations (1 − 6%) and four temperatures (20, 40, 60 and 80°C).
461 citations
TL;DR: Understanding the conditions and mechanisms that underlie movements of N across the gut should enhance the ability to manipulate feed and husbandry to improve production efficiency, as current data would suggest that sheep are more efficient than cattle.
308 citations
TL;DR: It was concluded that aromatized powders have no significant effect on the seed germination rate and storage bioassays were run to assess the long-term effect of powders aromatization with essential oils of Ocimum.
299 citations
TL;DR: A review of the research on N fertilizer management for no-till cereal production in the Canadian Great Plains, on mainly Chernozem and Gray soils, was done to illustrate the management practices which can be used to optimize the N use efficiency so as to minimize the N loss from root zone and environmental damage as discussed by the authors.
Abstract: Nitrogen (N) is the nutrient most limiting crop production in all areas of the world and is generally applied to soil in the largest quantity. A review of the research on N fertilization management for no-till cereal production in the Canadian Great Plains, on mainly Chernozem and Gray soils, was done to illustrate the management practices which can be used to optimize the N use efficiency so as to minimize the N loss from root zone and environmental damage. Applied N is subject to loss by volatilization, immobilization, denitrification and leaching in soil and its efficiency of use by plants is governed by soil and climatic factors, fertilizer material, and soil, crop and fertilizer management practices. Overall efficiency of applied N has been <70%. Reducing tillage intensity modifies both the demand of crops for N due to changes in yield potential, and the supply of N due to changes in N cycling and losses. Consequently, it may be necessary to compensate for this by adjusting the fertilizer rate. Fertilizer use efficiency may also change with changes in tillage management, microclimate, microbial activity and distribution of fertilizer relative to crop residue. Placing the fertilizer in a band reduces contact with soil microorganisms, reducing immobilization of both ammonium (NH4) and nitrate (NO3). Banding also slows the conversion of urea to NH3 and NH4 to NO3, which can reduce losses by denitrification and leaching. The use of the urease inhibitor n-(n-butyl) thiophosphoric triamide (NBPT) shows promise in improving the efficiency of surface-applied urea-containing fertilizers in no-till systems and reducing seedling damage from seed-placed fertilizers. Ultimately, any N fertilization package has advantages and disadvantages. In selecting the optimum fertilizer management system for a farming operation, the balance between rate of application, cost and availability of equipment, soil disturbance, seedbed quality, moisture conservation, time and labor constraints and fertilizer use efficiency must be considered. The “best” management system is not fixed, but depends on the major limiting factors on each individual farm.
292 citations
TL;DR: Lowbush blueberries were consistently higher in anthocyanins, total phenolics, and antioxidant capacity, compared with highbushblueberries, and there was no relationship between fruit size and Anthocyanin content in either species.
Abstract: Recent interest in the possible protective effects of dietary antioxidant compounds against human degenerative disease has prompted investigation of foods such as blueberries (Vaccinium sp.), which have a high antioxidant capacity. Fruit obtained from genotypes of highbush blueberries (Vaccinium corymbosum L.) and lowbush blueberries (Vaccinium angustifolium Aiton) were analyzed for their antioxidant capacity, their content of anthocyanins, and total phenolic compounds, to evaluate the intraspecific and interspecific variation in these parameters. The method of extraction influenced the composition of fruit extracts; the highest anthocyanin and total phenolic contents and antioxidant capacity were found in extracts obtained using a solvent of acidified aqueous methanol. Regardless of the method, lowbush blueberries were consistently higher in anthocyanins, total phenolics, and antioxidant capacity, compared with highbush blueberries. There was no relationship between fruit size and anthocyanin content in either species.
TL;DR: Tomato yield was not affected by using the plant activator in the field when complemented with fungicides to manage foliar fungal diseases, but tomato transplant dry weight was negatively impacted and population densities on greenhouse-grown tomato transplants were reduced by acibenzolar-S-methyl treatment.
Abstract: Acibenzolar-S-methyl (CGA 245704 or Actigard 50WG) is a plant activator that induces systemic acquired resistance (SAR) in many different crops to a number of pathogens. Acibenzolar-S-methyl was evaluated for management of bacterial spot (Xanthomonas axonopodis pv. vesicatoria) and bacterial speck (Pseudomonas syringae pv. tomato) of tomato in 15 and 7 field experiments, respectively. Experiments were conducted over a 4-year period in Florida, Alabama, North Carolina, Ohio, and Ontario using local production systems. Applied at 35 g a.i. ha-1, acibenzolar-S-methyl reduced foliar disease severity in 14 of the 15 bacterial spot and all 7 bacterial speck experiments. Disease control was similar or superior to that obtained using a standard copper bactericide program. Acibenzolar-S-methyl also reduced bacterial fruit spot and speck incidence. Tomato yield was not affected by using the plant activator in the field when complemented with fungicides to manage foliar fungal diseases, but tomato transplant dry weight was negatively impacted. X. axonopodis pv. vesicatoria population densities on greenhouse-grown tomato transplants were reduced by acibenzolar-S-methyl treatment. Bacterial speck and spot population densities on leaves of field-grown plants were not dramatically affected. Acibenzolar-S-methyl can be integrated as a viable alternative to copper-based bactericides for field management of bacterial spot and speck, particularly where copper-resistant populations predominate.
TL;DR: The predicted biological value and protein efficiency ratio of beach peaprotein isolates indicated the high quality of products so prepared and the pH and NaCl concentration effectively changed the functional properties of protein isolates.
TL;DR: It was concluded that the cold-activation of BN115 requires membrane rigidification, cytoskeleton reorganization, Ca2+ influx and action of several types of protein kinases.
Abstract: Previous studies on cold-triggered events leading to Ca2+ influx during cold acclimatization have been conducted on either unicellular cyanobacterium Synechocystis or plant cell suspensions, and used transcript levels of cold-induced genes as end-point markers. Whether the results of these studies are valid for intact plants or their organs is not known. Here we examine cold signaling in transgenic Brassica napus seedlings carrying, in addition to the endogenous cold-inducible BN115 gene, the beta-glucuronidase (GUS) gene placed under control of the BN115 promoter. The activity of BN115 promoter was monitored at the transcriptional and translational levels by determining accumulation of BN115 transcripts and by histochemical assay of GUS activity. Cold-activation of BN115 was strongly inhibited by the membrane fluidizer benzyl alcohol, but mimicked at 25 degrees C by the membrane rigidifier dimethylsulfoxide (DMSO). The cold induction of BN115 was also inhibited by stabilizers of microtubules and actin microfilaments, taxol and jasplakinolide, respectively, but was mimicked at 25 degrees C by microtubule destabilizer oryzalin or colchicine, or by microfilament destabilizer latrunculin B. Gd3+ or ruthenium red prevented the cold activation of BN115, but Ca2+ ionophore A23187 or cyclic ADP-ribose activated it at 25 degrees C. Inhibitors of tyrosine kinases, protein kinase C and phosphoinositide kinases prevented the cold activation of BN115, but inhibitors of protein phosphatases (PP) 1 and 2 A activated BN115 at 25 degrees C. Constitutively expressed GUS activity in another transgenic line of the same cultivar of B. napus, was not affected by cold or any of the chemical treatments used in the experimentation. Activation of BN115 at 25 degrees C by DMSO, Ca2+ ionophore, cADPR, and by inhibitors of PP1 and 2A was accompanied by an increased freezing tolerance. It was concluded that the cold-activation of BN115 requires membrane rigidification, cytoskeleton reorganization, Ca2+ influx and action of several types of protein kinases.
TL;DR: An evaluation of various lactic acid bacteria for the fermentation of cabbage, carrot and beet-based vegetable products was carried out, and the selection process enabled the preparation of a mixed culture that was more rapid than the silage inoculants in acidifying the medium and was more effective in reducing the production of gas during the fermentation and storage of the fermented vegetables.
TL;DR: It is a weed of orchards, vineyards, roadsides, and arable fields where tillage has been reduced or eliminated and serves as a wild host of the tarni shed plant bug and of aster yellows, a mycoplasma disease transmitted by the aster leaf hopper.
Abstract: Conyza canadensis (L.) Cronq. (Canada fleabane, horseweed, mare’s-tail) is a winter or summer annual, native to North America, and found in all provinces of Canada except Newfoundland. It is a weed of orchards, vineyards, roadsides, and arable fields where tillage has been reduced or eliminated. Most seedlings emerge from late August through October and form rosettes which overwinter. Large numbers of small, wind-dispersed seeds, ranging to over 200 000 seeds per plant, are produced in late summer. Populations of C. canadensis in more than ten countries have evolved resistance to herbicides such as paraquat, atrazine, chlorsulfuron or glyphosate. Several paraquat resistant populations were found in orchards in Essex Country, Ontario. It serves as a wild host of the tarni shed plant bug, and of aster yellows, a mycoplasma disease transmitted by the aster leaf hopper. Key words: Canada fleabane, ERICA, Conyza canadensis, Erigeron canadensis, horseweed
TL;DR: In this study, extent of grain processing and intake of ruminal available starch were the most influential factors affecting milk production and reducing the ratio of F:C improved total digestion and actual milk production.
TL;DR: In this article, the number, genome location, effect and allele phase of QTLs determining agronomic traits in the two North American malting barley (Hordeum vulgare L.) quality variety standards were estimated using simple interval mapping and simplified composite interval mapping procedures.
Abstract: A better understanding of the genetics of complex traits, such as yield, may be achieved by using molecular tools. This study was conducted to estimate the number, genome location, effect and allele phase of QTLs determining agronomic traits in the two North American malting barley (Hordeum vulgare L.) quality variety standards. Using a doubled haploid population of 140 lines from the cross of two-rowed Harrington×six-rowed Morex, agronomic phenotypic data sets from nine environments, and a 107-marker linkage map, we performed QTL analyses using simple interval mapping and simplified composite interval mapping procedures. Thirty-five QTLs were associated, either across environments or in individual environments, with five grain and agronomic traits (yield, kernel plumpness, test weight, heading date, and plant height). Significant QTL×environment interaction was detected for all traits. These interactions resulted from both changes in the magnitude of response and changes in the sign of the allelic effect. QTLs for multiple traits were coincident. The vrs1 locus on chromosome 2 (2H), which determines inflorescence row type, was coincident with the largest-effect QTL determining four traits (yield, kernel plumpness, test weight, and plant height). QTL analyses were also conducted separately for each sub-population (six-rowed and two-rowed). Seven new QTLs were detected in the sub-populations. Positive transgressive segregants were found for all traits, but they were more prevalent in the six-rowed sub-population.QTL analysis should be useful for identifying candidate genes and introgressing favorable alleles between germplasm groups.
TL;DR: Chromatographic analysis indicated differences in composition between the more toxic DSD oil of A. absinthium and the other two extracts of this plant, indicating that a sesquiterpene (C15H24) compound present in the D SD oil and absent in the other three may enhance the toxicity of the DSDOil.
Abstract: Essential oils of Artemisia absinthium L. and Tanacetum vulgare L. were extracted by three methods, a microwave assisted process (MAP), distillation in water (DW) and direct steam distillation (DSD), and tested for their relative toxicity as contact acaricides to the twospotted spider mite, Tetranychus urticae Koch. All three extracts of A. absinthium and of T. vulgare were lethal to the spider mite but to variable degrees. The LC50 obtained from the DSD oil of A. absinthium was significantly lower (0.04 mg/cm2) than that of the MAP (0.13 mg/cm2) and DW (0.13 mg/cm2) oil of this plant species. DSD and DW extracts of T. vulgare were more toxic (75.6 and 60.4% mite mortality, respectively, at 4% concentration) to the spider mite than the MAP extract (16.7% mite mortality at 4% concentration). Chromatographic analysis indicated differences in composition between the more toxic DSD oil of A. absinthium and the other two extracts of this plant, indicating that a sesquiterpene (C15H24) compound present in the DSD oil and absent in the other two may enhance the toxicity of the DSD oil. Chemical analysis of the T. vulgare extracts indicated that β-thujone is by far the major compound of the oil (>87.6%) and probably contributes significantly to the acaricidal activity of the oil.
TL;DR: The current set of 16S rRNA hybridization probes targeting methanogenic Archaea does not cover the phylogenetic diversity present in the rumen and possibly other gastro-intestinal tract environments.
Abstract: Background
Interest in methanogens from ruminants has resulted from the role of methane in global warming and from the fact that cattle typically lose 6 % of ingested energy as methane. Several species of methanogens have been isolated from ruminants. However they are difficult to culture, few have been consistently found in high numbers, and it is likely that major species of rumen methanogens are yet to be identified.
TL;DR: Measure of size, through body size or mass, is the proxy easiest to use while providing good comparative values; however, care must be taken when using a single proxy, as proxies can be affected differently by rearing conditions of the parasitoid.
Abstract: Fitness, defined as the per capita rate of increase of a genotype with reference to the population carrying the associated genes, is a concept used by biologists to describe how well an individual performs in a population. Fitness: is rarely measured directly and biologists resort to proxies more easily measured but with varying connection to fitness. Size, progeny survival, and developmental rate are the most common proxies used in the literature to describe parasitoid fitness. The importance of the proxies varies between papers looking at evolutionary theories and those assessing ecological applications. The most direct measures of fitness for parasitoids are realised fecundity for females and mating ability for males, although these proxies are more difficult to measure under natural conditions. For practical purposes, measure of size, through body size or mass, is the proxy easiest to use while providing good comparative values; however, care must be taken when using a single proxy, as proxies can be affected differently by rearing conditions of the parasitoid. [KEYWORDS: LARVAL COMPETITION; QUALITY-CONTROL; CLUTCH SIZE; HOST; HYMENOPTERA; FIELD; SELECTION; WASP; SUPERPARASITISM; ICHNEUMONIDAE]
TL;DR: The results suggest a lack of comfort may be apparent in reduced time spent lying and a subsequent increase in time spent standing without eating and an increase in the bout duration of lying suggests that cows on concrete flooring have difficulty standing up and lying down.
TL;DR: Manure application rates should be reduced in nonirrigated and irrigated plots to more closely match manure P inputs to crop P requirements.
Abstract: Historically, manure has been recognized as an excellent soil amendment that can improve soil quality and provide nutrients for crop production. In areas of high animal density, however, the potential for water pollution resulting from improper storage or disposal of manure may be significant. The objective of this study was to determine the P balance of cultivated soils under barley (Hordeum vulgare L.) production that have received long-term annual manure amendments. Nonirrigated soils at the study site in Lethbridge, AB, Canada, have received 0, 30, 60, or 90 Mg manure ha(-1) (wet wt. basis) while irrigated plots received 0, 60, 120, and 180 Mg ha(-1) annually for 16 yr. The amount of P removed in barley grain and straw during the 16-yr period was between 5 and 18% of the cumulative manure P applied. There was a balance between P applied in manure and P recovered in crops and soils (to the 150-cm depth) of nonirrigated plots during the 16-yr study. In irrigated plots, as much as 1.4 Mg P ha(-1) added (180 Mg ha(-1) yr(-1) treatment) was not recovered over 16 yr, and was probably lost through leaching. The risk of ground water contamination with P from manure was greater in irrigated than nonirrigated plots that have received long-term annual manure amendments. Manure application rates should be reduced in nonirrigated and irrigated plots to more closely match manure P inputs to crop P requirements.
TL;DR: This review summarizes the progress of Canadian research on Sclerotinia diseases in the past 50 years, with specific emphasis in the areas such as strain differentiation, epidemiology, new types of sclerotia, survival and germination of sclerosis, and biocontrol.
Abstract: Sclerotinia sclerotiorum (Lib.) de Bary and Sclerotinia minor Jagger are two of the species in the genus Sclerotinia found in Canada. While S. sclerotiorum is distributed country-wide and causes disease on numerous economically important crops including oilseeds, pulses, forage legumes, vegetables, and ornamentals, S. minor has only been reported on lettuce in Quebec and Ontario. During the past five decades, Canadian researchers have made a substantial contribution to the understanding of the biology and control of S. sclerotiorum and, to a lesser extent, of S. minor. This review summarizes the progress of Canadian research on Sclerotinia diseases in the past 50 years, with specific emphasis in the areas such as strain differentiation, epidemiology, new types of sclerotia, survival and germination of sclerotia, and biocontrol. Le Sclerotinia sclerotiorum (Lib.) de Bary et le Sclerotinia minor Jagger sont deux especes du genre Sclerotinia trouvees au Canada. Alors que le S. sclerotiorum a une distribution...
TL;DR: Cows milked alone in an unfamiliar room showed signs of acute stress and gave less milk due to higher residual milk and reduced oxytocin secretion, but had no effect on milk yield or hormonal responses.
TL;DR: In this article, the connaissances des emballages for assister les producteurs and les vendeurs dans leur choix d'emballage are enumerated.
TL;DR: In this paper, a revue de litterature porte sur les effets osmotiques and ioniques of the conductivite electrique (CE) de la solution nutritive and de ses liens avec les facteurs climatiques and culturaux sur le rendement and la qualite de the tomate de serre.
Abstract: Cette revue de litterature porte sur les effets osmotiques et ioniques de la conductivite electrique (CE) de la solution nutritive et de ses liens avec les facteurs climatiques et culturaux sur le rendement et la qualite de la tomate de serre L'ajustement de la salinite de la solution nutritive permet aux producteurs de modifier la disponibilite en eau pour la plante de facon a controler la qualite des fruits Cependant, des salinites elevees affectent le rendement vendable Sous une haute CE, le calibre des fruits est inversement relie a la CE alors que le contenu en matiere seche des fruits augmente lineairement avec la CE Le taux de reduction du rendement varie selon les interactions entre la CE et les cultivars, les facteurs environnementaux, la composition de la solution nutritive, et la gestion de la culture Selon differentes etudes et conditions de croissance des plants, une CE plus elevee que 23-51 mScm -1 entraine une baisse de rendement alors qu'une salinite de 35-90 mScm -1 ameliore la qualite des fruits La manipulation du climat de la serre (humidite relative, temperature, niveau de CO 2 ambiant) peuvent compenser les effets negatifs engendres par de hautes salinites sur le rendement et la qualite des fruits L'intensite lumineuse recue par la plante affecte directement la quantite de photoassimilats disponibles pour les fruits, accroit leur rapport sucre: acide, influence les taux de transpiration et d'absorption de l'eau par les plants, lesquels influencent la CE de la zone radiculaire L'accroissement de la salinite par l'ajout de NaCl reduit le contenu en acides titrables, en potassium et en azote des fruits et augmente leur contenu en sodium Le NaCl accroit la qualite gustative des fruits et la perception d'une saveur plus sucree Selon la composition de la solution nutritive, des deficiences ou toxicites nutritionnelles peuvent survenir suite a une predominance d'ions specifiques ou a une competition parmi les cations et les anions De facon a obtenir des rendements eleves de tres grande qualite tout au long de la saison de production, un equilibre entre les elements nutritifs de la rhizosphere doit etre preserve pour chacun des stades de croissance Cet article presente plusieurs strategies de gestion de la CE afin d'ameliorer la qualite de la tomate de serre
TL;DR: In this article, Extended X-ray absorption near edge structure (EXAFS) spectroscopy analyses were performed on aqueous pastes containing Cu(II) and goethite (α-FeOOH) with humic acid adsorbed at 0, 14, 28, 57, 88, 216, and 236 g kg−1 goethites.
TL;DR: A phenotypically polymorphic barley mapping population was developed using morphological marker stocks as parents and several molecular markers were found to be closely linked to morphological loci, aiding in map-based cloning of genes controlling morphological traits.
Abstract: A phenotypically polymorphic barley (Hordeum vulgare L.) mapping population was developed using morphological marker stocks as parents. Ninety-four doubled-haploid lines were derived for genetic mapping from an F1 using the Hordeum bulbosum system. A linkage map was constructed using 12 morphological markers, 87 restriction fragment length polymorphism (RFLP), five random amplified polymorphic DNA (RAPD), one sequence-tagged site (STS), one intron fragment length polymorphism (IFLP), 33 simple sequence repeat (SSR), and 586 amplified fragment length polymorphism (AFLP) markers. The genetic map spanned 1,387 cM with an average density of one marker every 1.9 cM. AFLP markers tended to cluster on centromeric regions and were more abundant on chromosome 1 (7H). RAPD markers showed a high level of segregation distortion, 54% compared with the 26% observed for AFLP markers, 27% for SSR markers, and 18% for RFLP markers. Three major regions of segregation distortion, based on RFLP and morphological markers, were located on chromosomes 2 (2H), 3 (3H), and 7 (5H). Segregation distortion may indicate that preferential gametic selection occurred during the development of the doubled-haploid lines. This may be due to the extreme phenotypes determined by alleles at morphological trait loci of the dominant and recessive parental stocks. Several molecular markers were found to be closely linked to morphological loci. The linkage map reported herein will be useful in integrating data on quantitative traits with morphological variants and should aid in map-based cloning of genes controlling morphological traits.
TL;DR: Data demonstrate that a large population of Entodinium spp.
Abstract: Fermentation characteristics were measured and numbers and distribution by genera of ciliate protozoa were determined in ruminal fluid samples collected from 10 ruminally cannulated steers during the first 30 d of their being fed barley-based diets containing 62% (Medium Barley) or 95% (High Barley) barley grain (DM basis). Ruminal samples were collected at 5-d intervals over the 30-d periods beginning after adaptation (i.e., at the first full feeding of each diet). Ruminal pH and ammonia concentrations were lower (P < 0.001) with the High Barley than with the Medium Barley diet. Concentrations of total VFA and propionate and amylase activity of ruminal fluid were higher (P < 0.001) on High Barley than on Medium Barley. Total protozoal numbers in ruminal fluid were 42% lower (P < 0.05) on High Barley (470 x 10(3)/mL) than on Medium Barley (804 x 10(3)/mL). On Medium and High Barley diets, respectively, Entodinium spp. made up 89 and 91% of the ciliate protozoal populations. With the Medium Barley diet, relative proportions of Dasytricha, Ophryoscolex, Ostracodinium, Diplodinium, and Metadinium spp. in the total ciliate population were 4.5, 0.4, 0.5, 0.7, and 0.3%, respectively. When the High Barley diet was fed, these genera were not detected. In a subsequent survey, ruminal samples were collected from 200 finishing cattle at slaughter. Average protozoal population was 328 x 10(3)/mL, and Entodinium spp. constituted 97% of the total. These data demonstrate that a large population of Entodinium spp. can persist in the rumen of cattle fed high barley grain-based finishing diets.