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In vitro production of trichothecenes and zearalenone by Fusarium isolates from equatorial barley (Hordeum vulgare l.) grown in Kenya
KM Mbae, C Kiiyukia, GM Kenji
African Journal of Food, Agriculture, Nutrition and Development , 2012,
Abstract: Fusarium head blight (scab) is a devastating disease of wheat and barley throughout the world. The disease has been reported worldwide wherever cereals are grown, cutting across diverse ecological and geographical distribution. In addition to being pathogenic to plants, which may cause severe crop yield reduction, many Fusarium species are also capable of producing mycotoxins deleterious to human health as secondary metabolites. Fusarium toxins are commonly detected in wheat, barley, maize, rice and beer. Traditionally malted barley (Hordeum vulgare L.) is the principal ingredient in clear beer and Fusarium toxins incidences are of major concern. Moreover, the spent grain from the brewing industry is used as feed and presence of mycotoxins can lead to harmful effects on domestic animals and also find a way into the human food chain. Studies carried out in Kenya have revealed presence of various Fusarium species with ability to produce mycotoxins and presence of Fusarium toxins in wheat and maize and beer. Based on the ubiquitous nature of Fusarium mold and the fact that barley production takes place in maize and wheat growing areas, this study set out to investigate the occurrence of Fusarium molds in Equatorial barley grown in Kenya and the ability of the isolates to produce selected mycotoxins. Grain samples were obtained from newly delivered barley lots originating from two regions and stored grain awaiting malting after break of dormancy from Kenya Maltings Ltd., Nairobi. The Fusarium isolates were identified to species level based on cultural and morphological characteristics. Additionally, they were screened in-vitro on rice cultures for their ability to produce Type A trichothecenes (T–2 toxin, HT–2 toxin, Diacetoxyscirpenol), Type B trichothecenes (deoxynivalenol and nivalenol) and Zearalenone. Samples from all sources were contaminated with Fusarium, but at varying magnitudes - 50%, 33.3% and 25% for barley kernels originating from Timau, Olchoro and in-storage grain with no common history of origin, respectively. The distribution of the species showed some regional specificity. F. graminearum and F. poae predominated in kernels sourced from Olchoro region. All strains of F. graminearum produced both deoxynivalenol and zearalenone. F. poae strains and F. chlamydosporum did not produce detectable amounts of the screened mycotoxins. However, two inconclusively identified isolates of Fusarium spp. isolated from Timau samples produced deoxynivalenol only. The study revealed that a number of toxigenic Fusarium spp. do occur in Equatorial barley grown in Kenya.
Comparative Germination of Barley Seeds (Hordeum Vulgare) Soaked in Alkaline Media and Effects on Starch and Soluble Proteins
A Perveen, IM Naqvi, R Shah, A Hasnain
Journal of Applied Sciences and Environmental Management , 2008,
Abstract: Barley seeds (Hordeum Vulgare) were germinated after soaking in different alkaline solutions of varied concentrations and pH, at room temperature of 25oC. The rate of germination after 48 hours of soaking of the seeds in distilled water was found to be 35% and the rate for the seeds soaked in the solutions of Ca (OH)2 , KOH and Mg(OH)2 was observed as 60, 66 and 62% respectively. Where-as the rate of germination for the solutions of NaOH and NaHCO3 remained the same as that of the water. The influence in length of rootlets was also examined as a function of the nature of the soaking solutions. Sharp increase in the length was observed in case of Mg (OH)2 and KOH while in NaOH, Ca(OH)2 and NaHCO3 increase in rootlets length was found insignificant . Variation of starch and soluble protein contents in soaked solutions were also examined. Starch and soluble protein contents were found to be the highest in NaOH soaked seeds as 57.7 and 5.95% respectively, compared to 45.07 and 2.50 % for the seeds soaked in water
Comparison of stability statistics for yield in barley (Hordeum vulgare L.)
Z Mut, A Gülümser, A Sirat
African Journal of Biotechnology , 2010,
Abstract: Analysis of multienvironment trials (METs) of crops for cultivar evaluation and recommendation is an important issue in plant breeding research. Evaluating both stability of performance and high yield is essential in MET analyses. The objectives of this study were to assess interrelationship among these measures and to identify high-yield and stable barley (Hordeum vulgare L.) cultivars in 11 environments during 2001 - 2003 in the central Black Sea region of Turkey. Significant differences were observed among barley cultivars for grain yield, thousand-grain weight, hectoliter weight, plant height and heading date. In this study, high values of TOP (proportion of environments in which a genotype ranked in the top third) was associated with high mean yield, but the other methods were not positively correlated with mean yield and instead characterized a static concept of stability. The results of principal component (PC) analysis and correlation analysis of parametric and nonparametric stability statistics and yield indicated that only TOP method would be useful for simultaneously selecting for high yield and stability. This method recommended Fahrettinbey and Sladoran as stable and Balkan 96 and Erginel as unstable genotypes. A biplot of the first two PCs also revealed that the stability statistic methods grouped as three distinct classes that corresponded to different dynamic (agronomic) and static (biological) concepts of stability.
Transcriptome Analysis of the Vernalization Response in Barley (Hordeum vulgare) Seedlings  [PDF]
Aaron G. Greenup,Sharyar Sasani,Sandra N. Oliver,Sally A. Walford,Anthony A. Millar,Ben Trevaskis
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0017900
Abstract: Temperate cereals, such as wheat (Triticum spp.) and barley (Hordeum vulgare), respond to prolonged cold by becoming more tolerant of freezing (cold acclimation) and by becoming competent to flower (vernalization). These responses occur concomitantly during winter, but vernalization continues to influence development during spring. Previous studies identified VERNALIZATION1 (VRN1) as a master regulator of the vernalization response in cereals. The extent to which other genes contribute to this process is unclear. In this study the Barley1 Affymetrix chip was used to assay gene expression in barley seedlings during short or prolonged cold treatment. Gene expression was also assayed in the leaves of plants after prolonged cold treatment, in order to identify genes that show lasting responses to prolonged cold, which might contribute to vernalization-induced flowering. Many genes showed altered expression in response to short or prolonged cold treatment, but these responses differed markedly. A limited number of genes showed lasting responses to prolonged cold treatment. These include genes known to be regulated by vernalization, such as VRN1 and ODDSOC2, and also contigs encoding a calcium binding protein, 23-KD jasmonate induced proteins, an RNase S-like protein, a PR17d secretory protein and a serine acetyltransferase. Some contigs that were up-regulated by short term cold also showed lasting changes in expression after prolonged cold treatment. These include COLD REGULATED 14B (COR14B) and the barley homologue of WHEAT COLD SPECIFIC 19 (WSC19), which were expressed at elevated levels after prolonged cold. Conversely, two C-REPEAT BINDING FACTOR (CBF) genes showed reduced expression after prolonged cold. Overall, these data show that a limited number of barley genes exhibit lasting changes in expression after prolonged cold treatment, highlighting the central role of VRN1 in the vernalization response in cereals.
FERTILIZING BREWING BARLEY (Hordeum vulgare L.)
Imre Kádár,Gy?rgy Béndek,József Koncz
Poljoprivreda (Osijek) , 2000,
Abstract: Four levels of N, P and K nutrition (poor, moderate, satisfactory and high) and all their possible combinations with 64 treatments in two replications (128 plots) were studied in a long term field trial on barley yield and malting quality. A standard East-European spring barley "Opal" (bred in Czechoslovakia) was grown in 1986, 13th year of the agricultural experiment, involving various crops in previous years, on a calcareous loamy chernozem soil. The optimum fertility levels for yield enhancement resulted in the poorest malting quality: low modification and extract but long saccharification time and high protein. To solve this problem the brewing industry will have to apply the well-known technological methods available since growers are not likely to give up their fertilizers. Applying soil and plant analysis data, having knowledge about both soil and plant optimum values, the danger of the excessive use of fertilizers can be realized and decreased.
Relative efficacy of organic manures in spring barley (Hordeum vulgare L. ) production  [PDF]
Ofosu-Anim J,Leitch M
Australian Journal of Crop Science , 2009,
Abstract: The effect of organic sources of nutrients on the growth of spring barley (Hordeum vulgare L.) was studied in a pot experiment in a heated glasshouse at the University of Wales, Aberyswyth from November 2006 to March 2007. Spring barley seeds were sown in 120 pots containing a mixture of peat and 180g dry weight of poultry manure, cowdung, chicken manure pellet, sheep manure and horse manure. Chicken manure pellet was applied at 3.0 g pot-1 as top dressing. Mineralization pattern of the organic manures was monitored in a parallel experiment with 24 pots containing only the growth media. In this study, organic manures significantly increased plant height and chlorophyll content of leaves over the control plants. The application of inorganic fertilizer increased plant height over chicken manure and compost. In addition chlorophyll content was higher with inorganic fertilizer than cowdung at six weeks after germination. N mineralization significantly varied among organic manure sources with compost having the highest mineralized N and sheep manure the least. Plant tissue analysis revealed significant differences in plant tissue nutrient composition under organic manure treatment. Growing plants in organic manure resulted in 1.2 to1.6-folds, 1.1 to 4-fold and 1.1 to 4.1-fold increases in total N content of plant tissue at four weeks, eight weeks and twelve weeks after germination, respectively. Dry matter production by plants was also significantly increased under organic manure treatments. Organic manure application had the potential of increasing spring barley yield by 1.5 to 4-fold. Cowdung appeared to be the best source of organic manure for spring barley production.
Hordein variation in Brazilian barley varieties (Hordeum vulgare L.) and wild barley (H. euclaston Steud. and H. stenostachys Godr.)
Echart-Almeida, Cinara;Cavalli-Molina, Suzana;
Genetics and Molecular Biology , 2000, DOI: 10.1590/S1415-47572000000200031
Abstract: sds-page was used to analyze the hordein polypeptide patterns of brazilian barley varieties (hordeum vulgare l.) and of two native species of hordeum from southern brazil (h. euclaston steud. and h. stenostachys godr.). forty different hordein polypeptide bands with molecular weights ranging from 30 to 94 kda were found in the seeds of the three species studied. twelve of the 14 varieties examined showed intravarietal polymorphism. the number of bands ranged from 10 to 17, depending on the variety, and from 3 to 13 among individual seeds, with a total of 26 bands in h. vulgare. phenograms using each seed as an operational taxonomic unit (otu) showed that the seeds from most varieties did not form distinct clusters. seeds from different plants of the native species varied considerably. the molecular weights of the hordein polypeptides of the two native species were quite different from those of h. vulgare. there was a greater similarity between the native species than with h. vulgare, although h. stenostachys was slightly closer to the cultivated species than h. euclaston.
Hordein variation in Brazilian barley varieties (Hordeum vulgare L.) and wild barley (H. euclaston Steud. and H. stenostachys Godr.)  [cached]
Echart-Almeida Cinara,Cavalli-Molina Suzana
Genetics and Molecular Biology , 2000,
Abstract: SDS-PAGE was used to analyze the hordein polypeptide patterns of Brazilian barley varieties (Hordeum vulgare L.) and of two native species of Hordeum from southern Brazil (H. euclaston Steud. and H. stenostachys Godr.). Forty different hordein polypeptide bands with molecular weights ranging from 30 to 94 kDa were found in the seeds of the three species studied. Twelve of the 14 varieties examined showed intravarietal polymorphism. The number of bands ranged from 10 to 17, depending on the variety, and from 3 to 13 among individual seeds, with a total of 26 bands in H. vulgare. Phenograms using each seed as an operational taxonomic unit (OTU) showed that the seeds from most varieties did not form distinct clusters. Seeds from different plants of the native species varied considerably. The molecular weights of the hordein polypeptides of the two native species were quite different from those of H. vulgare. There was a greater similarity between the native species than with H. vulgare, although H. stenostachys was slightly closer to the cultivated species than H. euclaston.
Response of Barley (Hordeum vulgare L.) at Various Growth Stages to Salt Stress
Shazia Naseer
Journal of Biological Sciences , 2001,
Abstract: A pot experiment was conducted during winter 1996-97, to determine the response of barely (Hordeum vulgare L.) at various growth stages to salt stress (0, 8, 12 and 16 dS m -1 NaCl). A progressive decrease occurred in all the growth and yield parameters with increasing soil salinity. Grain yield was reduced by 45.83% at higher salinity level as compared to control. Among the varieties, Jow-83 proved comparatively better than Jow-87. Salinity affected at all the growth stages but it was more pronounced at vegetative stage than flower initiation and grain filling stages.
Rhizobial Lipo-Chitooligosaccharides and Gibberellins Enhance Barley (Hordeum vulgare L.) Seed Germination
M. Miransari,D. Smith
Biotechnology , 2009,
Abstract: Gibberellins are plant hormones, enhancing seed germination. The bacterium-to-plant signal, lipo-chitooligosaccharides (LCOs) or Nod factors, are of great importance for roots organogenesis and hence, nodule formation and N fixation. Hence, we hypothesized that LCOs like gibberellins may also enhance barley (Hordeum vulgare L.) germination. The objectives were to test the effects of gibberellins on barley germination and to test the hypothesis that LCOs may increase seed germination in barley. The concentrations, tested were 10-5 M for gibberellins and 10-6 M and 10-7 and 10-8 M LCOs. Although, gibberellins were able to numerically increase barley germination (up to 18%), the LCOs seemed to be more effective on barley germination as they significantly increased seed germination (up to 44%). Hence, the novel finding indicates that for LCOs may also be very effective on barley seed germination, through inducing morphogenesis and physiological changes in seeds. This finding can have very important agricultural implications.
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