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A RFLP approach was used to investigate polymorphism of ω -gliadin genes in Ae. tauschii using a F 2 population from the cross of accessions AUS18913 and CPI110856. A set of 150 F 2 progenies was genotyped by acid polyacrylamide gel electrophoresis (A-PAGE) and only one recombinant line of Gli-D t 1/Gli-D t T1 was observed. Twelve restriction enzymes were initially tested on genomic DNA of the two parents of which four restriction enzymes revealed polymorphism. Of these four, only Dra I was associated with the novel ω -gliadin gene (T 1 ) using a 1,200 bp DNA fragment of a ω -gliadin gene as a gene-specific probe. The ω -gliadin gene (T 1 ) may be of interest for further studies relating storage proteins and wheat bread-making quality.

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Cereal Research Communications
Authors: A. shahnejat Bushehri, A. Salavati, B. yazdi Samadi, M. Hassani, and S. Shahnejat Bushehri

A collection of new and obsolete Iranian bread wheat cultivars were characterized for gliadins using acid polyacrylamide gel electrophoresis (A-PAGE). Extensive polymorphism (H) = 0.734 in gliadin patterns was found. A total of 26 band patterns including 13, 8 and 5 different mobility bands were identified, in the zones of ω-, β + γ- and α-gliadins, respectively. There were a few patterns specific to each region and some were common among all the regions. Patterns of α-gliadin C, β + γ-gliadins A, and ω-gliadins H, C and E patterns were significantly higher in temperate and tropical zones. β + γ-gliadin C and ω-gliadin Q were significantly higher in Caspian-cold regions. Variation was observed in gliadins patterns of cultivars grown in different regions in Iran. Individual cultivars showed unique gliadin fingerprints. There were larger variation in ω- and γ + β-gliadins than in α-gliadins. These results may provide complementary information for relating genetic diversity, and quality characterization of Iranian wheat cultivars.

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Abstract  

Electron paramagnetic resonance (EPR) studies of -irradiated uranium doped BaCO3 have shown the formation of CO3 , CO2 , O3 and O2 ions. Thermally stimulated luminescence (TSL) glow curves of the -irradiated samples in the 300–600 K range have exhibited an intense peak around 360 K and a weak one around 440 K. The trap parameters for these peaks have been determined from TSL data. Spectral studies of the glow have revealed emission around 566, 583 and 590 nm characteristic of the uranate ion. From studies on the thermal stabilities of the radical ions, it has been inferred that the glow peak around 360 K is associated with the thermal destruction of O2 ion and the peak around 440 K is associated with the thermal destruction of CO3 ion.

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Abstract  

A method based on synergic extraction has been evolved for the recovery of tens of milligrams of americium from analytical wastes in 7-8M HNO3 medium containing excess uranium as a two step procedure viz., (1) separation of uranium by contacting with TBP in dodecane and (2) recovery of americium by an extraction-cum-strip cycle using a synergic mixture of PMBP-TBP in dodecane after decreasing the acidity of the solution. Other transition metals such as iron found in significant proportion were separated from Am by using the difference in the kinetics of extraction of iron and americium into HPMBP-TBP-dodecane mixture by short duration contacts. About 99% of Am could be recovered into about 20% of its initial volume.

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Abstract  

Thermally stimulated luminescence (TSL) and electron paramagnetic resonance (EPR) investigations were carried out on gamma irradiated SrBPO5 samples doped with CeO2 and co-doped with CeO2 and Sm2O3. On gamma-irradiation at room temperature, BO3 2–, O2 and O radicals were produced. It was seen that the O radical ion disappeared in the sample annealed at 500 K. It is proposed that the recombination between trapped electrons and O radical ions results in transfer of recombination energy to the impurity centre Ce3+ resulting in TSL glow peak at 485 K. In the case of co-doped samples energy transfer occurs between Ce3+ to Sm3+ resulting in increase in the intensity of glow peak at 485 K.

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Abstract  

A chemical separation procedure has been developed for the extraction of uranium from some of the crucially important rare earths using a novel extractant viz. Cyanex-272 (2,4,4-trimethyl pentyl phosphinic acid). The near total extraction of uranium and quantitative separation of rare earth elements has been validated using inductively coupled argon plasma - atomic emission spectrometry (ICP-AES). The recovery of some of the representative elements has been confirmed by radioactive tracer studies. The back extraction of uranium from the organic phase was carried out using a solution of 0.5M Na2CO3 which resulted in a near total recovery of uranium into the organic phase. These studies have enabled determination of sub ppm amounts of the analyte elements with a precision of 5% RSD utilizing prior chemical separation of rare earths from 1 g uranium samples in just three extractions with Cyanex-272.

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Abstract  

This paper describes the results of photoreduction of uranyl (UO2 2+) ion to U4+ in 0.2M HNO3 and ethanol using a 308 nm XeCl excimer laser. The effects of different concentrations of ethanol and the addition of sulfamic acid on the quantum yield for U4+ formation are discussed.

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The effects of Mycosphaerella graminicola , the causal agent of Septoria tritici blotch of wheat on the content and quality of storage proteins were studied. Field research was undertaken by comparing plots with and without artificial inoculation. Twenty-one Syrian cultivars, 11 ( Triticum aestivum L.) and 10 ( T. turgidum var. durum Desf.) were used in this study. The results show high differences in the susceptibility levels among cultivars which were subsequently divided into four groups: resistant, moderately resistant, moderately susceptible and highly susceptible. Results also showed that protein content decreased significantly in severely infected cultivars. However, the disease did not affect the protein quality using both A-PAGE and SDS-PAGE techniques.

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High molecular weight glutenin and 1BL.1RS translocation employing the standard sodium dodecyl sulphate (SDS-PAGE) and acid (A-PAGE) polyacrylamide gel electrophoresis methods were classified in 43 Slovak wheat cultivars registered between 1976 and 2006. Total number of 9 alleles was detected at all Glu-1 loci. The most frequent HMW-GS alleles were “Null” for Glu-1A , 7+9 for Glu-1B and 5+10 for Glu-1D , respectively. At the same time these alleles also constituted the most frequent HMW-GS genotype and phenotype-0, 7+9, 5+10. Such HMW-GS combination was found in 48.8% of all genotypes analyzed in Triticum aestivum L. ssp. aestivum . Eleven different HMW-GS genotype-phenotype combinations were found, occurring at various frequencies.

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The objective of this study is the analysis of polymorphism in seed endosperm proteins (gliadins and glutenins) of Turkish cultivated einkorn wheat [Triticum monococcum ssp. monococcum] landraces. The genetic diversity of high-molecular-weight (HMW) glutenin subunits and the gliadin proteins in 10 landrace populations of cultivated einkorn wheat, originating from Turkey, was investigated using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and ammonium lactic acid polyacrylamide gel electrophoresis (A-PAGE), respectively. For glutenins, the mean number of alleles, the mean number of effective alleles, the mean value of genetic diversity and the mean value of average genetic diversity were detected as 3.50, 2.98, 0.65 and 0.28, respectively. The genetic differentiation was 0.57, while gene flow was 0.19 between populations. For gliadins, the mean number of alleles, the mean number of effective alleles, the mean value of total genetic diversity and the genetic diversity within population were detected as 2.00, 1.21, 0.17 and 0.15, respectively. The genetic differentiation was 0.08, whereas gene flow was 6.15 between populations. STRUCTURE is a software package program for population genetic analysis, was used to infer population structures of landraces populations. The optimum value for K was obtained as 10. Considering the high number of proteins and genetic variation, and increased interest in organic products, the farming of einkorn wheat should be supported and conservation of germplasm in landraces should be maintained as important genetic resources. The landraces germplasm should be conserved for future crop improvement processes.

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