36 research outputs found
Greenbug resistance in barley landraces from Uzbekistan
Background. The greenbug (Sсhizaphis graminum Rondani) can significantly reduce the yield of barley and other cereals in the southern regions of Russia. Cultivation of resistant varieties can significantly limit the pathogen’s harmfulness. At the same time, specific interaction with the genotypes of the host plant, characteristic of S. graminum, requires a continuous search for new resistance donors to broaden the genetic diversity of barley cultivars. Materials and methods. The resistance of 178 accessions of barley landraces from Uzbekistan to the Krasnodar greenbug population was tested in laboratory experiments. Juvenile plants were infested with aphids of different ages, and when the susceptible control died (cv. ‘Belogorsky’), resistance was assessed on a 0 to 10 (plant death) rating scale. Plants with a damage rate of 1–4 points (up to 30% of the leaf surface being damaged) belonged to the resistant class; damage rate of 5–8 points indicated moderate resistance of plants, and that of 9–10 meant susceptibility. In addition, we assessed the aphid damage of the winter barley cultivar ‘Post’, protected by the previously identified resistance gene Rsg1.Results and conclusions. We identified 52 barley accessions as heterogeneous for the studied trait. In six accessions, plants with high (points 3 to 4) and moderate (5 to 8) resistance were identified; 6 accessions were differentiated into 3 phenotypic classes: resistant, moderately resistant, and susceptible; and in 40 accessions the manifestation of the resistance component varied within 5 to 7 points (from 31 to 60% of the leaf surface being damaged). The distinctly expressed resistance of 12 accessions is controlled by alleles of resistance genes that differ from Rsg1. After selection for resistance, the identified accessions can be used in breeding
Diversity of barley accessions from the Asian part of Russia in greenbug resistance
Background. The use of barley cultivars resistant to greenbug (Schizaphis graminum Rondani) is an effective, economical and ecology-friendly way to control the dangerous phytophage. The insect is able to overcome the resistance of the host plant, which necessitates a relentless search for new genes to ensure reliable protection of barley fields from the pest.Materials and methods. Resistance to the Krasnodar greenbug population was assessed in 345 barley accessions from the Asian part of Russia. Besides, resistance to S. graminum was studied in cv. ‘Post’ (carrier of the Rsg1 gene), a pure line derived from cv. ‘Onokhoisky’ (k-16626, Buryatia) heterogeneous for this trait, and landraces from Mongolia (k-3885, k-3904, and k-4080). Juvenile plants were infested with aphids in the laboratory, and when a susceptible control died, the damage to experimental barley accessions was assessed using a scoring scale. Genetic control of greenbug resistance in the line derived from cv. ‘Onokhoisky’ was studied using the insect’s test clones and an analysis of the segregation in F2 hybrids from crossing the resistant line with cv. ‘Belogorsky’ susceptible to the aphid, when the plants were infested with the Krasnodar population of the phytophage and with clones of S. graminum.Results and conclusions. We identified 7 accessions heterogeneous for aphid resistance. Among them, plants with a high level of greenbug resistance were found in three landraces from Tuva (k-14714, k-14718, and k-14733). Resistance was also clearly expressed in the line derived from cv. ‘Onokhoisky’. This cultivar is protected by a dominant allele that differs from the previously identified Rsg1, as well as from the alleles found in Mongolian landraces k-3904, k-4080, and k-3885. ‘Onokhoisky’ also has genes with low expressivity, which manifest themselves when the main gene for resistance to S. graminum appears ineffective
The efficiency of using case-method for training staff of the higher qualification
В статье отмечено значение применения кейс-технологий для подготовки инженерных кадров высшей квалификации. Обозначено, что кейсовые чемпионаты являются эффективным инструментом для передачи будущим специалистам-инженерам практических знаний, опыта и новых компетенций. Приведены доказательства, что метод с использованием кейсов, имеет актуальность, эффективность и востребованность по сравнению с традиционными методами обучения, так как реализует главные образовательные аспекты: практическую направленность, интерактивный формат и конкретные навыки.The article notes the importance of using case technologies for the training of highly qualified engineering personnel. It is indicated that case championships are an effective tool for transferring practical knowledge, experience and new competencies to future engineers. Evidence is given that the method using cases is relevant, effective and in demand in comparison with traditional teaching methods, as it implements the main educational aspects: practical orientation, interactive format and Soft skills
nnovative Seasonal Migrations and Subsistence System of the Mobile Pastoralists of the Desert-Steppe Zone of Eurasia:role of social groups
The study of the economic system of the earliest nomads which inhabited the Eurasian desert-steppe belt in 5000-2000 is a relevant task of contemporary studies. The data on the organization of living space and the role of social groups of early prehistoric pastoralists in the exploitation of open steppe resources are scarce. The paper presents a new methodological approach to searching camps of the earliest pastoralists. The application of this approach enabled the archaeologists to discover numerous seasonal camps in the Sal-Manych Ridge located in the western part of the Eurasian steppes, including Eneolithic camps dated to 4200-3600 BC. The study of the occupation layers at the sites, evaluation of the productivity of pasture systems made it possible to categorize such sites as short-term seasonal camps occupied by pastoralists, evaluate the role of social groups in the organization of innovative seasonal migrations and reconstruct their subsistence system. The camps emerged as a result of developing pastoral economic strategy in the Lower Don region and the abutting areas reflecting the role of special social groups of pastoralists who managed to organize seasonal moves and address the issue of exploiting pastures located beyond the permanently occupied area
nnovative Seasonal Migrations and Subsistence System of the Mobile Pastoralists of the Desert-Steppe Zone of Eurasia:role of social groups
nnovative Seasonal Migrations and Subsistence System of the Mobile Pastoralists of the Desert-Steppe Zone of Eurasia:role of social groups
Quality of life of patients of the physiathritic profile.
The article emphasizes the relevance of studying the indicators of the quality of life of patients with a phthisiological profile. The results of the study of the quality of life structure in patients with pulmonary tuberculosis and extrapulmonary tuberculosis, namely tuberculosis of the osteo-articular system, without HIV infection and with HIV infection are presented.В статье подчеркивается актуальность изучения показателей качества жизни пациентов фтизиатрического профиля. Представлены результаты исследования структуры качества жизни у пациентов с легочной и внелегочной формой туберкулеза, а именно туберкулезное поражение костно-суставной системы у ВИЧ больных и у пациентов без сопутствующей ВИЧ инфекции соответственно
Hybrid nanoparticles based on sulfides, oxides, and carbides
The methods for synthesis of hybrid nanoparticles based on sulfides, oxides, and carbides of heavy and transition metals were considered. The problem of the influence of the method of synthesis of the hybrid nanoparticles on their atomic structure, morphology of the nanomaterials, and functional properties was analyzed. The areas of practical use of the hybrid nanoparticles were proposed. © 2013 Springer Science+Business Media New York
Origin of Axial and Radial Expansions in Carbon Nanotubes Revealed by Ultrafast Diffraction and Spectroscopy
The coupling between electronic and nuclear degrees of freedom in low-dimensional, nanoscale systems plays a fundamental role in shaping many of their properties. Here, we report the disentanglement of axial and radial expansions of carbon nanotubes, and the direct role of electronic and vibrational excitations in determining such expansions. With subpicosecond and subpicometer resolutions, structural dynamics were explored by monitoring changes of the electron diffraction following an ultrafast optical excitation, whereas the transient behavior of the charge distribution was probed by time-resolved, electron-energy-loss spectroscopy. Our experimental results, and supporting density functional theory calculations, indicate that a population of the excited carriers in the antibonding orbitals of the nanotube walls drives a transient axial deformation in ∼1 ps; this deformation relaxes on a much longer time scale, 17 ps, by nonradiative decay. The electron-driven expansion is distinct from the phonon-driven dynamics observed along the radial direction, using the characteristic Bragg reflections; it occurs in 5 ps. These findings reveal the nonequilibrium distortion of the unit cell at early times and the role of the electron(phonon)-induced stress in the lattice dynamics of one-dimensional nanostructures