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Application of Metabolomic Analysis in Exploration of Plant Genetic Resources

Abstract

The article addresses the issues of using metabolomic analysis to study genetic resources of cereal crops in order to (1) determine phylogenetic linkages between species (the degree of domestication); (2) within species to describe genetic diversity according to its responses to biotic and abiotic stressors and biochemical characteristics (chemical compounds) determining food, feed and technological quality indicators; and (3) select the most resistant and highest-quality geno-types for complex breeding use.

Open access
Content of Phenolic Compounds and Antioxidant Activity in Fresh Apple, Pomace and Pomace Water Extract — Effect of Cultivar

Abstract

The study aimed to evaluate the chemical composition (total phenol, flavonoid, and tannin content and the antioxidant activity) of 11 apple (Malus domestica) cultivars in fresh apples and their processing by-products — apple pomace and its water extract. In addition, the proportion of chemical compounds and antioxidant activity in fresh apples and pomace transferred to the resulting water extract was calculated. Three different season’s cultivars (autumn–winter, winter and late winter) were selected in the research, and significant differences between chemical parameters within groups were found. Cultivars ‘Zarja Alatau’, ‘Belorusskoje Malinovoje’, ‘Sinap Orlovskij’ and ‘Antej’ are characterised by a higher content of determined compounds in fresh apples, pomace and po-mace water extract. The results showed that the water extract in relation to fresh apples and apple pomace still contains an appropriate amount of total phenols, flavonoids and tannins in the range 2.5–9.6%. These results indicated that apple pomace water extracts could be recommended for use in food as well as in the pharmaceutical industry.

Open access
Effect of Soil Properties on the Spread of Heterobasidion Root Rot

Abstract

The literature review focuses on the effect of forest soil properties on infection of coniferous trees and stumps by Heterobasidion spores and further growth of mycelium from tree to tree. Spread of the fungus is greater in alkaline soil. Forest plantations on former agricultural lands have an increased risk of infection, due to lack of antagonistic soil microorganisms. In Latvia, severe infection of spruce stands by Heterobasidion root rot has been observed on peat soils.

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Genetic and Agronomic Analysis of Latvian Fescue (Festuca Spp.), Ryegrass (Lolium Spp.) Accessions and their Hybrids

Abstract

The development of ecologically adaptable fodder crop varieties is of increasing importance, particularly in the context of climate change. New varieties should be phenotypically and ecologically plastic and able to adapt to differing climactic and soil conditions, ensuring high yields and persistence. Combining Festuca and Lolium species and the development of hybrid (Festulolium) cultivars can be a promising method of combining high yield, high feed quality, persistence, as well as cold, frost and drought tolerance. Breeders at the Institute of Agriculture of Latvia University of Life Sciences and Technologies have been utilizing Festulolium germplasm for several decades. Currently, in cooperation with the molecular genetics laboratory and Latvian gene bank at the Latvian State Forest Research Institute “Silava”, analysis of Festuca, Lolium and their hybrids with DNA markers has been initiated, in order to gain additional knowledge about the breeding material and to increase the efficiency of the breeding process. Results of the assessment of morphological and agronomic traits in long-term field trials are combined with DNA markers analyses in order to determine the correlation of genetic and phenotypic traits.

Open access
High-Temperature X-Ray Diffraction and Fluorescence Spectra of SnSe Single Crystal

Abstract

The temperature dependence of unit cell parameters was studied using high-temperature X-ray diffraction and the coefficient of thermal expansion of SnSe single crystal was determined. Fluorescence spectra of SnSe single crystal grown by the Bridgman-Stockbarger method were examined using a Cary Eclipse spectrophotometer at room temperature in the wavelength range 200–900 nm. When the samples were irradiated by a pulse at a wavelength of 230 nm, the fluorescence spectra exhibited maxima at wavelengths 313.07, 423.03, 458.93, 495.07, and 530.00 nm.

Open access
Jānis Oļģerts Ērenpreiss and his School of Cancer Research: Commemorating the 90th Anniversary

Abstract

Jānis Olģerts Ērenpreiss (1929–1996) was a prominent Latvian cancer researcher and theoretician. Starting out as a student, he contributed to the embryonal theory of cancer, experimentally proving the differentiation and regenerative normalisation capabilities of tumour cells. His theoretical work, presented in its most complete form in his final monograph Current Concepts of Malignant Growth (Zinātne Publ., Rīga, 1993), postulates that oncogenes are abnormally activated genes that are involved in gametogenesis and embryogenesis, and that carcinogenesis and senescence are mutually linked processes arising when the cell is exposed to stressful conditions. This article demonstrates how advancements in cancer research over the last decade have confirmed these core concepts, which were far ahead of their time, and how J. O. Ērenpreiss’ legacy continues both under the guidance of the author and in foreign laboratories, expanding understanding of the nature of malignant tumours and the perspectives of cancer treatment.

Open access
Limit Theorems for Bivariate Generalised Order Statistics in Stationary Gaussian Sequences with Random Sample Sizes

Abstract

In this paper, we study the limit distribution functions of the (lower-lower), (upper-upper) and (lower-upper) extreme and central-central m-generalised order statistics (m–GOS) of stationary Gaussian sequences under an equi-correlated set up, when the random sample size is assumed to converge weakly and independent of the basic variables. Moreover, sufficient conditions for a weak convergence of generalised quasi-range with random indices are obtained.

Open access
Morphological Analysis of Jerusalem Artichoke (Helianthus tuberosus L.) Accessions of Different Origin from VIR Collection

Abstract

The article is dedicated to morphological analysis of the Jerusalem artichoke genetic resources collected at the N. I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). The crop has a wide range of various usages, such as: food and feed, and medicinal, melliferous, and ornamental products. In this study, morphological characteristics of vegetative and generative plant organs (stems, leaves, tubers and inflorescences) from the VIR collections in the Maikop Experiment Station of VIR (Russian Caucasus, Republic of Adygea) and in Gatchina District, Leningrad Province, Russia were analysed. The widest range of variability was observed in accessions from Western Europe. Accessions from United States, Japan and Australia were the most unique in their set of traits, which may indicate specific paths of their evolution in these isolated territories. Accessions with unique combinations of studied traits were determined. Some traits characterizing leaf, inflorescence and tuber proved to be valuable for taxonomic and geographic analyses.

Open access
Novel Interactions of Adrenodoxin-Related [2Fe-2S] Plant Ferredoxins MFDX1 and MFDX2 Indicate Their Involvement in a Wide Spectrum of Functions in Plant Mitochondria

Abstract

Electron transfer chains of plant organelles (both chloroplasts and mitochondria) contain their own special set of ferredoxins. The relatively recently described adrenodoxin-like [2Fe-2S]-ferredoxins MFDX1 and MFDX2 of plant mitochondria are among the least studied of these. Until now, the only established function for them is participation in the final stage of biotin biosynthesis. In this work, using genetic and biochemical approaches, we searched for possible partners of these proteins in the genomes and proteomes of tobacco (Nicotiana tabacum L.) and foxglove (Digitalis purpurea L.) plants. MORF9 protein, one of the auxiliary components of the RNA editing complex of organelles (editosome), was found among the most prominent protein partners of adrenodoxin-like [2Fe-2S] tobacco ferredoxins. According to the results obtained from the yeast two-hybrid system, NtMFDX1 and NtMFDX2 of tobacco also bind and interact productively with the previously uncharacterised long non-coding polyadenylated RNA, which, based on its structural features, is capable of regulating the function of a number of components of complexes I (Nad1, Nad5) and III (protein of the cytochrome c synthesis system CcmF) and contributes to the formation of Fe/S-clusters in the corresponding protein complexes of the respiratory chain of plant mitochondria. We found one of the main components of the thiazol synthase complex (mitochondrial protein DpTHI1) to be the partner of ferredoxin DpMFDX2 of Digitalis purpurea. Finally, additional arguments were obtained in favour of the possible participation of MFDX1 and MFDX2 in the very ancient, but only recently described ‘progesterone’ steroid hormonal regulatory system: in leaves of the previously constructed CYP11A1-transgenic tomato plants, only the mature form of mitochondrial cytochrome P450scc (CYP11A1) of mammals is able to enter the mitochondria, where the above-mentioned components of the electron transport chain are localised. In summary, all of the newly revealed interactions of adrenodoxin-like [2Fe-2S] ferredoxins MFDX1 and MFDX2 indicate their participation in a wide range of functions in plant mitochondria.

Open access
Quality of Life in Pediatric Obesity in Latvia

Abstract

The aim of the retrospective case-control study was to determine if the health-related quality of life of overweight and obese children is lower than for children with optimal weight, using the KIDSCREEN-52 survey of health-related quality of life. The study examined differences in health-related quality of life assessments between children with optimal weight, and obese and over-weight children, as well as evaluated parental assessments of the quality of life of their children. In total, 200 children aged 8 to 18 years and their parents participated in the study. The results of the study showed that the total quality of life of obese (p < 0.0001) and overweight (p = 0.008) children was lower than for children with optimum weight (p = 0.001). Also, the assessments of quality of life between parents of obese (p < 0.0001) and overweight (p = 0.001) children scored lower than those of parents whose children had optimal weight.

Open access