Search results for "Hordeum"
showing 10 items of 74 documents
Effects of Ga3 and Ca2+ on barley aleurone protoplasts: a freeze-fracture study
1988
Freeze-fracture electron microscopy was used to study changes in the endomembrane system of barley (Hordeum vulgare L. cv. Himalaya) aleurone protoplasts. Protoplasts were used for this study because their response to calcium and the plant hormone gibberellic acid (Ga3) can be monitored prior to rapid freezing of cells for electron microscopy. Protoplasts incubated in Ga3 plus Ca2+ secrete elevated levels of a-amylase relative to cells incubated in Ga3 or Ca2+ alone. The endoplasmic reticulum (ER) and Golgi apparatus of protoplasts incubated in Ga3 plus Ca2+ undergo changes that are well correlated with the synthesis and secretion of a-amylase. The ER, which appears as short, single sheets …
Solid acid-catalyzed depolymerization of barley straw driven by ball milling
2015
This study describes a time and energy saving, solvent-free procedure for the conversion of lignocellulosic barley straw into reducing sugars by mechanocatalytical pretreatment. The catalytic conversion efficiency of several solid acids was tested which revealed oxalic acid dihydrate as a potential catalyst with high conversion rate. Samples were mechanically treated by ball milling and subsequently hydrolyzed at different temperatures. The parameters of the mechanical treatment were optimized in order to obtain sufficient amount of total reducing sugar (TRS) which was determined following the DNS assay. Additionally, capillary electrophoresis (CE) and Fourier transform infrared spectrometr…
Effective saccharification of lignocellulosic barley straw by mechanocatalytical pretreatment using potassium pyrosulfate as a catalyst
2017
The catalytic conversion of lignocellulosic biomass is attractive due to the feasible generation of valuable products such as reducing sugars which constitute the basic substrates for chemical and transportation fuel production, as well as the production of renewable hydrogen. This study shows the efficient conversion of lignocellulose, especially hemicellulose, into reducing sugars such as xylose and galactose, by mechanocatalysis using potassium pyrosulfate, K2S2O7, as an effective salt catalyst. Ball milling was performed, introducing a mechanical force which, combined with chemical pretreatment, leads to reducing sugar yields (40%) almost as high as when commonly used sulfuric acid was …
Efficacy of spot form of net blotch suppression in barley from seed, fertiliser and foliar applied fungicides
2022
Abstract Spot form of net blotch (SFNB), caused by Pyrenophora teres f. maculata is a prevalent and damaging foliar disease of barley (Hordeum vulgare). Fungicides are commonly used to manage SFNB infection and reduce production loss in susceptible varieties. This study determined the efficacy of suppression of SFNB and associated grain yield and quality improvements from application of fungicides to seed, fertiliser and/or foliar treatments. Eight field experiments were conducted in south-eastern Australia during 2016–2018. Two experiments compared single applications of different commercially available seed, fertiliser and foliar fungicides. Six experiments evaluated different growth stag…
Contamination of barley seeds with Fusarium species and their toxins in Spain: an integrated approach.
2013
Fusarium is a globally distributed fungal genus that includes different species pathogenic to cereals among others crops. Some of these Fusarium species can also produce toxic compounds towards animals and humans. In this work, the presence of the most important Fusarium toxins was determined in barley seeds from Spain, sampled according to European Union requirements. The results obtained were compared with the presence of mycotoxigenic species considered responsible for their synthesis by using species-specific polymerase chain reaction protocols. Fumonisins B(1) and B(2), zearalenone, trichothecenes type A (T-2 and HT-2) and trichothecenes type B (deoxynivalenol and nivalenol) were analy…
Survey of the mycobiota of Spanish malting barley and evaluation of the mycotoxin producing potential of species of Alternaria, Aspergillus and Fusar…
2005
The present work deals with the toxigenic mycobiota occurring in Spanish malting barley and the capability for producing mycotoxins by several important toxigenic fungi. One hundred and eighty seven samples of malting barley were gathered from Spanish breweries before processing. One hundred and fifty kernels per sample were surface-sanitized with a 2% sodium hypochlorite solution and incubated on three culture media. The most abundant fungi were species of Alternaria, Aspergillus, Penicillium and Fusarium, which were present in 93%, 82.3%, 57.8% and 27.8% of the samples, respectively. To evaluate their mycotoxin producing potential a number of isolates belonging to each genus, except Penic…
Contamination of Wheat, Barley, and Maize Seeds with Toxigenic Fusarium Species and Their Mycotoxins in Tunisia
2021
Abstract Background Fusarium is a worldwide distributed fungal genus. It includes different species pathogenic to cereals among others crops. Some of these species can also produce toxic compounds toward animals and humans. Objective In this work, occurrence of fumonisins B1+B2, zearalenone, type A trichothecenes (T-2 and HT-2 toxins), and type B trichothecenes (deoxynivalenol[DON] and nivalenol[NIV]) was studied in 65 samples of stored and freshly harvested wheat, barley, and maize collected in Tunisia. Methods Mycotoxins analyses were performed by using gas chromatography for type B trichothecenes and HPLC for other mycotoxins. Obtained results were compared with the presence of mycotoxig…
Molecular size and net charge of pathogenesis-related enzymes from barley (Hordeum vulgare L., v. Karat) infected withDrechslera teres f. teres (Sacc…
1998
Molecular size and net charge of isoforms of pathogenesis-related (PR) chitinase, beta-1,3-glucanase and peroxidase were studied in uninfected barley (Hordeum vulgare L., v. Karat) leaves and in barley leaves infected with the pathogenic fungus Drechslera teres f. teres (Sacch.) Shoem. Molecular characteristics were determined by time-dependent polyacrylamide gradient gel electrophoresis under native conditions and by applying an extended version of the computer program MOL-MASS (Rothe, G. M., Weidmann, H., Electrophoresis 1991, 12, 703-709). Uninfected barley leaves contained predominantly one peroxidase isozyme but also three very weak peroxidases. Activities of all of these three peroxid…
Development and implementation of high-throughput SNP genotyping in barley
2009
Abstract Background High density genetic maps of plants have, nearly without exception, made use of marker datasets containing missing or questionable genotype calls derived from a variety of genic and non-genic or anonymous markers, and been presented as a single linear order of genetic loci for each linkage group. The consequences of missing or erroneous data include falsely separated markers, expansion of cM distances and incorrect marker order. These imperfections are amplified in consensus maps and problematic when fine resolution is critical including comparative genome analyses and map-based cloning. Here we provide a new paradigm, a high-density consensus genetic map of barley based…
Changes in the genetic diversity of barley of Nordic and Baltic origin, studied by isozyme electrophoresis
2003
AbstractIn this study an evaluation was made of changes in the genetic variation of barley (Hordeum vulgare L.) of Nordic and Baltic origin, from the end of the 19th century until today. A comparison of Nordic and Baltic material with exotic material that has not been subjected to intense selection was also made. A total of 293 accessions, including 160 Nordic and 80 Baltic landraces, cultivars and breeding lines, and another 53 landraces of exotic origin (Central Asia), were surveyed using isozyme starch gel electrophoresis. For the four isozymes studied, 28 alleles at 11 loci were observed. The average total genetic diversity value (HT) for individual loci ranged between 0 and 0.519. In t…