Weeds and weed flora as the basis for phytosanitary zoning (a review)

The concept of “the weed flora” is still associated with weedy plants within agricultural phytocenoses, despite the fact that its association with a wider range of secondary habitat types with disturbed vegetation and soil cover was discussed as early as in the first half of the last century. The study of this characteristic feature of weeds has been continued at the present time, which is reflected in the very concept of “the weed” adopted by the state standards. The structure of the weed flora includes groups of weedy plant species within both naturally and anthropogenically disturbed habitats, so such notions as “the segetal flora” or “synanthropic flora” do not fully reflect the composition of the weed flora. The formation of the weed flora was historically linked with the emergence and development of cultivated plants. A regional weed flora is composed of weed plant species, for which this or that region is suitable in terms of growing conditions. In the context of agriculture and plant protection, the elementary weed flora is the flora of an agricultural landscape or an agricultural ecosystem, as its component. Phytosanitary zoning for a set of weed species confined to a specific territory is carried out at the macro-, meso-, and microlevels. The criterion for identifying the levels of phytosanitary zoning is the weed flora of different territorial levels

Distribution of wild carrots <i>Daucus carota</i> L. over the territory of the Russian Federation

A map showing the zone of the main distribution of wild carrots Daucus carota L. in the Russian Federation was compiled on the basis of the materials available in open-access scientific publications. According to the data on the frequency of the species’ occurrence in a separate area, found in published sources, the zone of the main distribution was divided into the optimum zone, where the species occurred with the “frequently” indicators, and the pessimum zone, where it occurred with the “rarely” indicators. The locations of single finds of the species listed in areas outside the main distribution zone were marked using information from the GBIF international database. Since wild carrots are both wild relatives of cultivated carrots and weedy plants, the presented map will be in demand among both plant breeders and plant protection experts

The structure of the segetal flora of field crops in the steppe zone of Krasnodar Territory

A comparative analysis of the species composition of the segetal flora of the surveyed steppe zone and the segetal flora of the entire Krasnodar Territory based on the materials of numerous scientific publications is presented. The main part of the floristic spectra of both segetal florae coincides in the composition of the 10 leading families, which attests to their unity. The leading families in the compared lists are Asteraceae Dumort., Poaceae Barnhart, Fabaceae Lindl., and Brassicaceae Burnett. Floristic homogeneity of the weed species compositions between the segetal floras in the areas under different types of field crops is considered. Besides, species with a high degree of permanency in the agrocenoses of each field crop have been identified. These species are objects of phytosanitary risk for a number of field crops or some of them in the steppe zone of Krasnodar Territory. The most common weeds in the fields of all surveyed crops are field bindweed (Convolvulus arvensis L.), common ragweed (Ambrosia artemisiifolia L.), bristly thistle (Cirsium setosum (Willd.) Bess.), and cockspur grass (Echinochloa crusgalli (L.) Beauv.). Information about the predicted widespread species in the fields under a certain crop will make it possible to plan the volume of production or purchase of protective means focusing on groups of dominant species, and anticipate possible changes in the reformatting of the acreage structure, violations of the reclamation system and crop rotation schemes, etc

Distribution of the common nettle Urtica dioica L. and annual nettle U. urens L. in the Russian Federation

Two widespread weedy species of Urtica L. (Urticaceaea Juss.), common nettle (Urtica dioica L.) and annual nettle (U. urens L.), possess many useful properties, so any information on their distribution is of practical interest. Numerous scientific publications with open access were used to map the areas of distribution for these species in the Russian Federation. While mapping the spatial arrangement of these taxa, the data on the frequency of their occurrence in separate administrative subdivisions of the country were employed. Areas where occurrences of an individual nettle species are scored as “very often”, “often”, “usually” or “often” were blended into one territory characterized with the “often” occurrence: this is the optimum zone for the species in question. Similarly, the pessimum zone for the species was identified as a combined territory of the areas where the occurrence was marked as “very rarely”, “rarely”, “infrequently” or “sporadically”. The pessimum zone included the areas located in the north of the range of species distribution: they are characterized by cooler and more humid environmental conditions than the optimum zone. The pessimum also incorporated the lands stretching in the southern part of the range: their environmental conditions are drier and warmer than those in both the optimum zone and the northern part of the pessimum zone. Therefore, plants of the same species, occurring in different parts of their area of distribution, are adapted to different hydrothermal conditions, which should be taken into account when selecting forms for further possible cultivation and use

Erythrocytes as regulators of blood vessel tone

A drop in oxygen partial pressure results in elevation of blood vessel diameter. It has been demonstrated that isolated vessels exhibit this unique feature only when they are perfused in the presence of erythrocytes. More recently, it was shown that haemoglobin plays a key role in oxygen sensing. Its deoxygenated form interacts with band 3 protein, triggering the cascade of non-identified intracellular signals involved in nitric oxide production and release of ATP interacting with P2Y purinergic receptors in endothelial cells. In this review, we summarize the data on mechanisms of ATP release from erythrocytes, as well as on its physiological and pathophysiological implications

Vasodilator effect of vascular endothelial growth factors (VEGF) in the conditions of bone tissue formation by the method of discrete traction in congenital segmental pathology

The development of the limbs in patients with congenital segmental defects is associated with defects in the vascular system of the same segment. In this case, vascular endothelial growth factors that participate in physiological angiogenesis may have effect on bone tissue formation in ontogenesis and participate in endochondral ossification. In this regard, the aim of the study was to compare the quantitative changes in growth factors (VEGF) and the contractile properties of arterioles under conditions of discrete distraction for congenital pathology of the lower leg bones. Materials and methods Subjects of the study were 12 patients with congenital pseudarthrosis of the lower leg (ICD-10 Q 74.0). Their serum was analyzed using an enzyme immunoassay. Microcirculation in the calf skin was examined by laser flowmetry (BLF21, Transonic Systems Inc., USA). We used the findings obtained from the study of blood serum in 103 somatically healthy people for control. Results Significant imbalance in serum concentrations of endothelial factors and their receptors was detected in the subjects with congenital pathology. As a result of surgical treatment, the imbalance of secretion of vascular growth factors and their receptors increased. Vasodilator effect in the precapillary vessels in the zone of the operated segment in patients with congenital pathology was not revealed by surgical intervention

A Database of Weed Plants in the European Part of Russia

Weeds are plants that, although not specially cultivated, grow and often adapt to growing in arable lands. They form an ecological variant of flora, as a historically-formed set of species growing on cultivated soils. For the rational use of the chemical and biological crop protection products and to produce safe and high-quality food, up-to-date data on the floristic diversity of weeds and the patterns of its geographical change are required. The need for a weeds' database arises that allows many specialists to work together independently. However, the great value of any database lies not in its existence, but in the accumulation of data that can be used to analyse the factors affecting the species diversity of weeds. New information A dataset of weed species diversity and their distribution in the European part of Russia, based on the results of the authors' own research from 1999 to 2019, has been created. The dataset includes 24,284 observations of occurrences of weed plants, which were obtained on the basis of 2,049 relevés of segetal plant communities in seven regions of the European part of Russia. In total, the dataset includes information about 329 species of vascular plants growing in 65 farmlands: cereals, spring and winter crops, industrial crops, row crops and perennial grasses (Tretyakova et al. 2020). © Tretyakova A et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Funding: This work was supported by Russian public funds (AAAA-A18-118011990151-7) in the framework of implementation of the State task on the “Vascular plants of Eurasia: taxonomy, ora, plant resources” (AAAA-A19-119031290052-1), by the Competitiveness of the Ural Federal University (Russian Federation Government Regulation no. 211, contract no. 02. A03.21.0006) and partially by the Russian Foundation for Basic Research (project nos. 17-44-020402 and 19-016-00135)

Development and Testing of Monoclonal Antibodies-Based Diagnostic Preparation for <i>Bacillus anthracis</i> Spores Detection Using Latex Agglutination Method

Immobilization of anti-B. anthracis monoclonal antibodies (MAbs) on latex microparticles was studied, the optimal load of these MAbs was determined to be 20 µg for 50 µl of the stock latex suspension. The highest sensitivity of latex agglutination test was observed for 1E6 MAbs. Latex suspensions with immobilized MAbs were lyophilized. Their sensitivity and specificity were shown to be highly competitive with those of the stock liquid latex suspension. Latex diagnosticum for Bacillus anthracis spores detection was constructed on the basis of these lyophilized reagents, developed and approved was the regulatory documentation that included their application instructions and technical specifications. Carried out were inter-laboratory and commission tests of experimental prototypes of the designed latex diagnosticum. These preparations demonstrated high sensitivity (from 1·105 to 2·106 spores/ml and even more) and specificity (absence of cross-reactions with spores of different species of sporogenous bacilli at concentration of 108 spores/ml)