250 research outputs found
A WIDE DISTRIBUTION OF A NEW VRN-B1c ALLELE OF WHEAT TRITICUM AESTIVUM L. IN RUSSIA, UKRAINE AND ADJACENT REGIONS: A LINK WITH THE HEADING TIME AND ADAPTIVE POTENTIAL
The adaptation of common wheat (T. aestivum L.) to diverse environmental conditions is greatly under the control of genes involved in determination of vernalization response (Vrn-1 genes). It was found that the variation in common wheat heading time is affected not only by combination of Vrn-1 homoeoalleles but also by multiple alleles at a separate Vrn-1 locus. Previously, we described the Vrn-B1c allele from T.aestivum cv. 'Saratovskaya 29' and found significant differences in the structure of the first (1st) intron of this allele when compared to another highly abundant Vrn-B1a allele, specifically, the deletion of 0.8 kb coupled with the duplication of 0.4 kb. We suggested that the changes in the intron 1 of Vrn-B1c allele caused earlier ear emergence in the near-isogenic line and cultivars, carrying this allele. In this study we investigate the distribution of the Vrn-B1c allele in a wide set of spring wheat cultivars from Russia, Ukraine and adjacent regions. The analysis revealed that 40% of Russian and 53% of Ukranian spring wheat cultivars contain the Vrn-B1c allele. The high distribution of the Vrn-B1c allele can be explained by a frequent using of 'Saratovskaya 29' in the breeding process inside the studied area. From the other hand, the predominance of the Vrn-B1c allele among cultivars cultivated in West Siberia and Kazakhstan may be due to the selective advantage of this allele for the region where there is a high risk of early fall frosts
Long-term preservation of modern Russian potato cultivars in the VIR cryobank
Cryopreservation of shoot-tips (apexes) excised from in vitro plants is used for long-term preservation of potato cultivars. The most widely used method for creating potato cryo-collections is droplet-vitrification of shoot-tips which, together with its numerous modifications, is widely used in genebanks. A modified protocol of droplet vitrification method is used at VIR for cryopreservation of shoot tips from in vitro potato plants. This paper presents the results of cryopreservation of modern cultivars which were released by seven Russian breeding centers. In vitro clones used in the cryopreservation experiments were genetically identical to the cultivarsâ nomenclatural standards and herbarium vouchers.The frequency of post-thaw regeneration in control experiments after short-term cryopreservation varied from 23.3 to 53.3%, depending on the genotype. Five out of 16 accessions (âVarĂągâ, âGusarâ, âEvpatijâ, âSolneÄnyjâ, âTangoâ)* had low post-cryogenic regenerative capacity from 20 to 30%; the regeneration rate exceeded 30% in 11 accessions, and 8 cultivars (âGrandâ, âZlatkaâ, âLinaâ, âSafoâ, âSiverskijâ, âSignalâ, âUtroâ, âĂnaâ) and âĐlyj Parusâ breeding clone had regeneration rate above 40%. The regeneration rate in the studied subset was genotype independent according to the ANOVA results (p=0.711). Viability and regeneration rate were significantly correlated (r=0.86). As a result of the experiments, explants of 14 modern cultivars and two breeding clones with the known post-thaw regeneration rate were successfully cryopreserved in the VIR cryobank. Four cultivars (âGrandâ, âGusarâ, âSignalâ, âUtroâ) were monitored for their regeneration capacity after the long-term (seven months) preservation in the VIR cryobank. On an average, these four cultivars demonstrated a post-thaw regeneration capacity of 41.8%. It can be concluded that the use of the modified method of droplet vitrification is relevant for increasing the VIR potato cryo-collection
Inheritance of signs of «many-flowered» common wheat and evaluation of productivity of the spike of F2 hybrids
Parameters of spike productivity in plants varieties Novosibirskaya 67 (N67), Saratovskaya 29 (S29), Puza-4 and «many-flowered» line Skle 123-09 were assessed in two years with different weather conditions. It was shown that «many-flowered» line Skle 123-09 is significantly higher in the number of grains per spike and number of grains per spikelet than varieties N67, S29 and Puza-4, and that the expression of «many-flowering» depends on the environmental conditions and the genetic background. It was shown that the «many-flowering» is a genetic trait and is therefore workable. A study of hybrids F2 ĐĄ29ĂSkle123-09, N67ĂSkle 123-09, P-4ĂSkle 123-09 isolated plants with fan-shaped cones and a high number of grains per spikelet as Skle 123-09 and having the best performance of other features as ear varieties recipients. The seeds of these plants will be used to secure «flowering». Two-factor analysis of variance showed that the number of grains per spike knotted depends on growing conditions, genotype and their interaction. Variability of grains per spikelet in drought-resistant varieties of S29 and Puza-4 is mainly dependent on the genotype and, to a lesser extent, on the «genotypeĂenvironment» interaction. In variety N67 created for West Siberia, only genotype is a factor. The weight of a grain per ear primarily is primarily affected by «genotypeĂenvironment» (almost 60 %), while the influence of «genotypeĂenvironmental» was half as strong. The variability of «masse of one grain» in F2 hybrids (S29, P-4ĂSkle123-09) is influenced by environmental factors, genotype and their interplay. Genotype accounts for the highest impact (> 70 %). F2 hybrids (N67ĂSkle 123-09) share the greatest variability in the «genotypeĂenvironment» interaction (77 %)
Mechanisms of Development of Heart Failure in Chronic Kidney Disease
The study of scientific data over the past 5 years has shown that cardiorenal syndrome, which has a
complex and multifactorial pathophysiology, is a clinical problem. Modern pharmacological methods of
treatment are effective, but insufficient to satisfactorily influence or mitigate the progression of
cardiorenal syndrome, therefore, the discovery of new drugs and new therapeutic strategies for
cardiorenal syndrome is a high priority tas
Enhanced AGAMOUS expression in the centre of the Arabidopsis flower causes ectopic expression over its outer expression boundaries
Spatial regulation of C-function genes controlling reproductive organ identity in the centre of the flower can be achieved by adjusting the level of their expression within the genuine central expression domain in Antirrhinum and Petunia. Loss of this control in mutants is revealed by enhanced C-gene expression in the centre and by lateral expansion of the C-domain. In order to test whether the level of central C-gene expression and hence the principle of âregulation by tuningâ also applies to spatial regulation of the C-function gene AGAMOUS (AG) in Arabidopsis, we generated transgenic plants with enhanced central AG expression by using stem cell-specific CLAVATA3 (CLV3) regulatory sequences to drive transcription of the AG cDNA. The youngest terminal flowers on inflorescences of CLV3::AG plants displayed homeotic features in their outer whorls indicating ectopic AG expression. Dependence of the homeotic feature on the age of the plant is attributed to the known overall weakening of repressive mechanisms controlling AG. Monitoring AG with an AG-I::GUS reporter construct suggests ectopic AG expression in CLV3::AG flowers when AG in the inflorescence is still repressed, although in terminating inflorescence meristems, AG expression expands to all tissues. Supported by genetic tests, we conclude that upon enhanced central AG expression, the C-domain laterally expands necessitating tuning of the expression level of C-function genes in the wild type. The tuning mechanism in C-gene regulation in Arabidopsis is discussed as a late security switch that ensures wild-type C-domain control when other repressive mechanism starts to fade and fail
CCQM-K90, formaldehyde in nitrogen, 2 ÎŒmol molâ 1 Final report
The CCQM-K90 comparison is designed to evaluate the level of comparability of national metrology institutes (NMI) or designated institutes (DI) measurement capabilities for formaldehyde in nitrogen at a nominal mole fraction of 2 ÎŒmol molâ1.
The comparison was organised by the BIPM using a suite of gas mixtures prepared by a producer of specialty calibration gases. The BIPM assigned the formaldehyde mole fraction in the mixtures by comparison with primary mixtures generated dynamically by permeation coupled with continuous weighing in a magnetic suspension balance. The BIPM developed two dynamic sources of formaldehyde in nitrogen that provide two independent values of the formaldehyde mole fraction: the first one based on diffusion of trioxane followed by thermal conversion to formaldehyde, the second one based on permeation of formaldehyde from paraformaldehyde contained in a permeation tube.
Two independent analytical methods, based on cavity ring down spectroscopy (CRDS) and Fourier transform infrared spectroscopy (FTIR) were used for the assignment procedure.
Each participating institute was provided with one transfer standard and value assigned the formaldehyde mole fraction in the standard based on its own measurement capabilities.
The stability of the formaldehyde mole fraction in transfer standards was deduced from repeated measurements performed at the BIPM before and after measurements performed at participating institutes. In addition, 5 control standards were kept at the BIPM for regular measurements during the course of the comparison.
Temporal trends that approximately describe the linear decrease of the amount-of-substance fraction of formaldehyde in nitrogen in the transfer standards over time were estimated by two different mathematical treatments, the outcomes of which were proposed to participants. The two treatments also differed in the way measurement uncertainties arising from measurements performed at the BIPM were propagated to the uncertainty of the trend parameters, as well as how the dispersion of the dates when measurements were made by the participants was taken into account.
Upon decision of the participants, the Key Comparison Reference Values were assigned by the BIPM using the largest uncertainty for measurements performed at the BIPM, linear regression without weight to calculate the trend parameters, and not taking into account the dispersion of dates for measurements made by the participant. Each transfer standard was assigned its own reference value and associated expanded uncertainty. An expression for the degree of equivalence between each participating institute and the KCRV was calculated from the comparison results and measurement uncertainties submitted by participating laboratories. Results of the alternative mathematical treatment are presented in annex of this report
Safety of vitamin D2 mushroom powder as a Novel food pursuant to Regulation (EU) 2015/2283 (NF 2019/1471)
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on vitamin D2 mushroom powder as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is produced from Agaricus bisporus mushroom that has been exposed to ultraviolet (UV) irradiation to induce the conversion of provitamin D2 (ergosterol) to vitamin D2 (ergocalciferol). The NF contains levels of vitamin D in the form of vitamin D2 in the range of 125â375 ”g/g. The information provided on the production process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF as an ingredient in a variety of foods and beverages in amounts that result in either 1.125 or 2.25 ”g vitamin D2 per 100 g or 100 mL of the food as consumed. The applicant also intends to add the NF in food supplements, for infants from 7 to 11 months at a maximum of 10 ”g vitamin D2/day and of 15 ”g vitamin D2/day for individuals aged 1 year or older, as well as in foods for special medical purposes (FSMPs) and total and meal diet replacement for weight control. For the adult population, the maximum intended use level in FSMPs is 15 ”g vitamin D2/day and 5 ”g vitamin D2/meal in total and meal diet replacement for weight control. The Panel concludes that the NF is safe under the proposed conditions of use. The Panel notes uncertainty regarding the calculated combined exposures to vitamin D for the general population, given the fact that the range of foods fortified with vitamin D has increased over the years, as well as the marketing of high-dose vitamin D supplements
Safety of vitamin D2 mushroom powder as a Novel food pursuant to Regulation (EU) 2015/2283 (NF 2020/2226)
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on vitamin D2 mushroom powder as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is produced from Agaricus bisporus mushroom powder that has been exposed to ultraviolet (UV) irradiation to induce the conversion of provitamin D2 (ergosterol) to vitamin D2 (ergocalciferol). The NF contains concentrations of vitamin D in the form of vitamin D2 in the range of 245â460 ÎŒg/g. The information provided on the production process, composition and specifications of the NF does not raise safety concerns. The applicant intends to add the NF as an ingredient in a variety of foods and beverages in amounts that result in either 1.2 or 2.4 ÎŒg vitamin D2 per 100 g or 100 mL of the food as consumed. The applicant also intends to add the NF in food supplements at a maximum of 15 ÎŒg vitamin D2/day for individuals above 1 year of age, as well as in foods for special medical purposes (FSMPs). The estimates for combined intake of vitamin D from the NF, the background diet and fortified foods, were below the ULs for vitamin D as established previously by the NDA Panel for children, adolescents and adults, i.e. 50 and 100 ÎŒg/day. The estimated combined vitamin D intake in infants (6â12 months) is also below the UL for vitamin D of 35 ÎŒg/day. The Panel considers that taking into account the composition of the NF and the proposed conditions of use, the consumption of the NF is not nutritionally disadvantageous for the proposed target population. The Panel concludes that the NF is safe under the proposed conditions of use
Safety of the extension of use of partially defatted chia seed (Salvia hispanica L.) powder with a high fibre content as a novel food pursuant to Regulation (EU) 2015/2283
Following a request from the European Commission, the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver an opinion on the safety of the extension of use of partially defatted chia seed (Salvia hispanica L.) powder with a high fibre content as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The NF is already authorised and included in the Union list of NFs and is produced according to the same production process. This application is limited to an assessment of the extension of use of the NF as a food ingredient in several food categories with a high moisture content that are subject to thermal processing. The target population for the extension of use is the general population. The information provided on the formation of process contaminants (acrylamide, furan and methylfurans) in a selected food category with added NF (bread) subjected to heat treatment is sufficient for this assessment and does not raise safety concerns. Noting that no safety concerns were identified from the information available on the production process, composition, specifications and proposed uses of the NF, the Panel considers that intake estimates for the NF are not needed for this assessment. The Panel concludes that the NF, partially defatted chia seeds powder with a high fibre content, is safe under the proposed conditions of use
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