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The emergence of the new SARS-CoV-2 coronavirus has given rise to many enigmas, to which there are no answers yet. However, the degree of threat to humanity, due to the fact that by the beginning of February 2021, more than 100 million people were ill in the world, of which 2 million died, led to the fact that the efforts of many researchers were aimed at combating this disease, including massive sequencing of the complete genomes of SARS-CoV-2, as this is necessary for diagnostics and prediction of the epidemiological situation, including in the long term. Currently, a fairly high level of conservativeness of the SARS-CoV-2 genome is shown, but there is also a significant variability of intra-host viral RNA, confirming the concept of the existence of quasispecies for RNA-containing viruses. As of February 2021, the complete genomes of almost half a million coronavirus isolates have been sequenced worldwide, and a number of nomenclatures have been proposed to streamline their analysis, including the convenient dynamic nomenclature Pango lineage. Variations of SARS-CoV-2 genomes in the form of consensus SNPs (Single Nucleotide Polymorphism) and intra-host iSNVs (intra-host Single Nucleotide Variant) were demonstrated. Taking into account iSNV and minor mutations, about 85% of the 29.9 thousand nucleotides viral genome were changed at least once, but only a very few of them turned into major mutations due to certain features that ensure the predominant distribution of such strains. The example of the S-protein gene, taking into account iSNV, minor and major mutations, shows its significant variability, which is detected when sequencing hundreds of thousands of SARS-CoV-2 genomes. On the basis of the analysis of 400 complete SARS-CoV-2 genomes isolated on the territory of the Russian Federation during 2020, the dynamics of the circulation of individual strains with acquired major mutations, the representation of which is slightly different from the changes in the SARS-CoV-2 genome in the rest world, is estimated. The possibility of long-term persistence of the new coronavirus in the human body is note, while the reservoirs for the latent existence of SARS-CoV-2, in contrast, for example, to the herpes simple virus, remain unknown. There is no consensus on the possibility of reactivation of SARS-CoV-2 or reinfection. The latter is theoretically possible in cases where SARS-CoV-2 strains belonging to other genetic lineages and clades are found in the body of the "re-infected". This, however, does not exclude the possibility of mutating the virus within a single host. Despite significant progress in monitoring the spread of SARS-CoV-2, many questions remain, but as knowledge of the biology of the new coronavirus accumulates, they will also be answered.

Sorghum (Sorghum bicolor (L.) Moench) is one of the world’s leading cereal crops in agricultural production, which has a special importance in the arid regions. However, unlike other cereals, sorghum grain has a lower nutritional value, which is caused, inter alia, by the resistance of its seed storage proteins (kafirins) to protease digestion. One of the effective approaches to improve the nutritional value of sorghum grain is to obtain mutants with partially or completely suppressed synthesis or altered amino acid composition of kafirins. The employment of genome editing may allow to solve this problem by introducing mutations into the nucleotide sequences of the α- and γ-kafirin genes. In this study, genomic target motifs (23 bp sequences) were selected for the introduction of mutations into the α- and γ-KAFIRIN genes of sorghum. The design of the gRNAs was conducted using the online tools CRISPROR and CHOPCHOP. Two most suitable targets were chosen for α-KAFIRIN (k1C5) and two for γ-KAFIRIN (gKAF1) genes. The insertion of respective sequences in the generic vector pSH121 was performed at the BsaI (Eco31I) sites. Validation of the cloning procedure was performed by DNA sequencing. Subcloning of the resulting constructs was performed using the SfiI restriction sites into the compatible binary vector B479p7oUZm-LH. The correct assembly of binary vectors was confirmed by restriction analysis using the MluI and SfiI cleavage sites. The four vectors created (1C - 4C) were transferred by electroporation into the Agrobacterium tumefaciens strain AGL0. Currently, this vector series is used for stable transformation of sorghum using immature embryo explants.

Background. An analysis of the spatial distribution of some taxonomically and ecologically related legumes in the Ural showed a nontrivial spatial distribution of related species of the genus Oxytropis DC of the Orobia Bunge section within the Uchalinsky uplands. Despite the similarities in ecology, these species practically do not grow together. Explicit spatial segregation of closely related plants over a relatively small area allows this phenomenon to be used as a convenient model for studying the effect of segregation of closely related legume species on the genetic composition of their nodule bacteria. Materials and methods. The genetic diversity of nodule bacteria entering into symbiosis with O. kungurensi s, O. baschkiriensis , O. approximata and O. gmelinii plants was studied. In addition, the polymorphism of their symbiotic genes has also been analyzed. Results. Phylogenetic characteristics of nodule bacteria endemic for the Southern Ural belonging to 4 species of leguminous plants of the genus Oxytropis of the section Orobia: O. kungurensis , O. baschkiriensis , O. approximata , O. gmelinii which are characterized by spatial separation of the growth sites, also called plant segregation, are given. It was shown that all of them belong to the genus Mesorhizobium despite certain phylogenetic differences of bacteria. Analysis of the symbiotic genes of the analyzed strains revealed a lack of congruence of their phylogeny with the core part of the genome. It was found that the microsymbionts of O. baschkiriensis plants differ in the phylogeny of nod-genes from nodule bacteria of other plants of the Oxytropis genus and are close to microsymbionts of plants of the Lupinaster genus growing in the Southern Urals. Conclusion. Acquisition of the property to enter into symbiosis with nodule bacteria of plants of the genus Lupinaster may turn out to be an adaptive mechanism that arose as a result of segregation of O. baschkiriensis from other species of Oxytropis .

For the first time, summarized data on the production of nine species and ten hybrids of pondweed (Potamogeton, Stuckenia, Potamogetonaceae) are given for ecosystems of small and medium rivers in the north of European Russia. The pondweed is shown to be an important producer of primary organic matter. A significant contribution to primary production in rivers in the region is due to large-size pondweeds and their hybrids, which form dense monodominant stands: P. lucens, P. natans, P. perfoliatus, P. × angustifolius, P. × nitens, P. × salicifolius, P. × sparganiifolius. The production characteristics for the widespread species (P. lucens, P. natans, P. perfoliatus) in the rivers of the region are more than 1.5 times greater than those in reservoirs. Most pondweed species and hybrids show medium productivity and produce

В 2020 году исполнилось 100 лет термину «геном», предложенному немецким ботаником Г.Винклером при описании партеногенеза в растительном и животном царствах. Этимология данного слова неясна, но нам представляется, что Винклер использовал игру слов, соединив морфемы «ген», «сома» и получив “genosom” (нем.), после чего решил удалить один слог, что и привело к краткому и емкому слову «геном», объединяющему гены и составляющем для них нечто целое, что также совпало с окончаниями «–ом» отдельных биологических терминов, обозначающих некое множество (в данном случае для генома – генов). Первоначально под геномом подразумевался гаплоидный набор хромосом, и таким образом хромосомы служили элементарной единицей генома. Сейчас же с появлением возможности секвенировать полный геном его элементарной единицей стала пара нуклеотидов, но и хромосомы оказались задействованными, поскольку нуклеотидные последовательности распределяются в базах данных по хромосомам, когда такое по результатам полногеномного секвенирования становится возможным. На протяжении столетия менялись взгляды ученых, что считать геномом, подразумевая под этим его гаплоидную или диплоидную природу. Сейчас принято считать, что геном - это нуклеотидные последовательности всей совокупности генов и прочих участков ДНК гаплоидного набора хромосом конкретного вида организмов, однако и габитус и функциональное состояние каждого организма определяется его полным диплоидным геномом, тогда как при сборке гаплоидного генома a priori происходит игнорирование тех или иных азотистых оснований в отличающихся аллелях, поскольку выбирается лишь один какой-то нуклеотид, что сразу снижает ценность такого генома, которая все равно очень высока, поскольку секвенирование полных гаплоидных геномов уже очень большого числа видов организмов различного уровня генетической сложности дало весьма важную информацию о Живом. Тем не менее, для персонифицированной медицины будущего нужны знания об исключительно диплоидных геномах людей, получение которых пока представляет серьезную проблему, в отличие от нынешних квази-гаплоидных геномов, которые секвенируются почти массово. Диплоидные геномы растений также представляют интерес, в том числе для CRISPR/Cas геномного редактирования, когда необходимо произвести изменения в обоих аллелях парных хромосом, и для этого знать их возможно отличающиеся нуклеотидные последовательности крайне необходимо. Равно как и по завершении такого редактирования следует с помощью полногеномного диплоидного секвенирования выявить произведенные целевые и нецелевые мутации. Разрабатываемые подходы полногеномного секвенирования, в том числе протяженных участков ДНК вкупе с компьютерными программами, рассчитанными на фазировку данных, недавно вызвали к жизни новый термин «гаплотиг», представляющий собой гаплотип-специфичный контиг. Вне всякого сомнения, все это позволит со временем перейти к уверенному установлению полных диплоидных геномов, что придаст термину «геном» новый смысл, считая его для эукариотических организмов диплоидным, что будет к тому же отражать и саму сущность организации генома, имеющего в норме двуродительскую природу.

This paper presents new data on the species of genus Vaucheria in Russia from analysis of original and museum collections. In total, 20 species were identified in 152 locations of 22 administrative regions of the European Russia, Western Siberia, and the Russian Far East. Vaucheria lii, a rare multiregional species new to Russia, has been found in 6 locations of the Vologda, Moscow, Nizhny Novgorod, Yaroslavl regions and North Ossetia. V. cruciata, V. schleicheri, V. taylorii, V. uncinata were recorded for the European Russia for the first time. V. birostris and V. pseudogeminata are new records for Western Siberia. Rank of V. terrestris var. nuoljae was raised up to separate species with V. terrestris var. major as a new synonym. The distributions of the frequently reported species, V. dichotoma and V. geminata, are critically analyzed.

Specific amplification of nucleic acids is a convenient and quick alternative to the culture-based method of detecting bacterial cells. However, conventional PCR and other amplification reactions can not differentiate between live bacteria and dead or dormant ones, and are also capable of amplifying DNA that persists for a long time and in a cell-free state. Several methods have been developed in order to establish the viability of microorganisms by amplification of specific sequences of nucleic acids, both those controlled by changing temperatures and isothermal ones. For some of them, DNA modified by phenanthridine dyes serves as a target, and simultaneous use of monoazides of ethidium and propidium was shown to be preferable for the purpose. For other methods, the targets are directly RNA molecules or their cDNA copies. Pre-rRNA detection seems to be the most preferable approach, due to the presence of these types of RNA exclusively in living cells.

The paper considers the problematic aspects of detecting a new coronavirus infection using RT-PCR, which often lead to false negative diagnostic results, which occur both at the preanalytic stage and during nucleic acid amplification, including the interpretation of the obtained data. The viral load in humans was evaluated and assumptions were made about the expected number of viral particles in the studied oropharyngeal and nasopharyngeal samples. The list of diagnostic test systems approved for use in the Russian Federation for detecting SARS-CoV-2 with their brief characteristics is given. The necessity of simultaneous use of several targets in the coronavirus genome in one test system detected by probes with the same fluorochrome is noted, which on the one hand increases the probability of detection by increasing the signal, and on the other hand eliminates the false negative results that could occur in the case of mutations in the virus genome at the sites of annealing primers and hybridization probes.

CRISPR/Cas genome editing of plants is realized in three basic variants, including knockout mutations as indels, insertion of alien DNA fragments, and base editing via deamination of nitrogenous bases. The most important stages of the CRISPR/Cas-based genome editing are the choice of a target site, design of guide RNAs, creation of genetically engineered constructions, and delivery of CRISPR/Cas components into a plant cell. Rapid developments in the field of plant genome editing with the use of CRISPR/Cas systems requires more detailed consideration of the last stage, so this review is dedicated to the description of the main ways to deliver CRISPR/Cas components into cells of higher plants. In the first studies on the genome editing of different plant species, these components were delivered to the target site mainly by Agrobacterium tumefaciens. This approach supposes integration of T-DNA into a genome and a stable expression of CRISPR/Cas components or their transient expression in the case of agroinfiltration. Another widespread approach included the use of plant viruses as delivery platforms; in this case, viruses were used mainly for production of an increased amount of guide RNAs that significantly improved the efficiency of genome editing. Another approach provides for the use of another bacterium, A. rhizogenes, as a platform for delivery of CRISPR/Cas components. This bacterium induces hairy root formation that may be an indirect confirmation of successful genome editing and assist in the selection of genetically modified forms. Other common ways to obtain genetically edited plants are the biolistic delivery of genetically engineered constructions into explants and various protoplast transformation technologies. The review also considers some issues transgenic and GM status of CRISPR/Cas-edited plants to transgenic and GM plants. There are a number of cases in which new organisms created by a CRISPR/Cas genome editing without any introduction of alien DNA were not considered as transgenic ones; it is quite possible that such plants will not fall under Russian legislation prohibiting GMO cultivation.

We present current information on the conservation of aquatic vascular plants in West and East Siberia and the Russian Far East. This includes the region from the Ural Mountains in the west to the eastern seaboard of Russia from Kamchatka and Chukotka in the north to Vladivostok in the south, including Sakhalin, the Kuril and Commander Islands. A list of aquatic vascular plant species protected in the region is presented with an indication of their conservation status derived from regional Red Data Books, combined with population trend data from the literature, as well as field observations made by the authors. The region as a whole supports a total of 246 aquatic plant species, of which 96 are listed as threatened in regional Red Lists. The main threats to these species are habitat degradation, eutrophication and pollution of water bodies as a consequence of human activity and climate change. Many species which are specialized, relict or endemic, and others occurring here on the edge of their range, are vulnerable because of these factors. The main conservation action needed includes protection of natural habitats, establishment of monitoring protocols for the most severely threatened species and research into the autecology of threatened species. There is also a need to resolve taxonomic questions obstructing conservation.

Tobacco hairy roots with constitutive expression of the NtEXPA5 expansin gene were obtained and analyzed, which were characterized by higher growth rates and increased productivity under normal conditions, as well as the action of stress factors.

Experiments on CRISPR/Cas9 mediated knock-in approaches in the PDS gene of various genes of interest were planned. Biolistic bombardment mediated delivery of target vectors to plant explants was suggested.

The genetic diversity and phylogeny of root nodule bacteria, microsymbionts of plants of the genus Lupinaster Adans. (L. albus Link and L. pentaphyllus Moench), were studied, and also their symbiotic genes were analyzed. The bacterial strains studied were shown to be phylogenetically different; however, all of them are related to the Mezorhizobium genus with the exception of the single strain which is related to the Rhizobium genus. Analysis of the symbiotic genes nifH and nodC revealed their high homology among all strains independently of strain phylogeny, as well as the phylogenetic relation of these genes to those of Mezorhizobium. Mezorhizobium bacteria are likely specific microsymbionts of these plants, while the Rhizobium strain acquired its symbiotic genes and became capable of nodule formation in Lupinaster plants through horizontal gene transfer. Thus, the genetic composition of nodule bacteria inhabiting Lupinaster plants represents additional support for the idea that they do not belong to the Trifolium genus.

The dataset for charophytes from the Middle Volga Region, including Orenburg region, Penza region, Samara region, Ulyanovsk region, Chuvash Republic, Republic of Mariy El, Republic of Mordovia, Republic of Tatarstan, have been updated under study of Russian charophytes. To date, 18 species from four genera were known from the study area according to published records. The reliability of records has been checked with specimens stored in LE, IBIW, PVB and our new collections of 2009–2017 for the period from 1768 to 2017. Fourteen species of Chara, Nitella and Tolypella only have been confirmed with vouchers. The published records of six species and one genus need to be confirmed. The data are scarce nearly for all administrative regions except Samara region. Chara inconnexa and C. subspinosa have been found in the Middle Volga Region for the first time. The single locality of the latter species is remarkable from its distribution range perspective and based on a single specimen from the 18th century. Some species have been found in separate regions for the first time. The novel species record for Ulyanovsk region is the first data about charophytes in the region. The species richness of charophytes from the Middle Volga Region is evidently low in comparison with the Upper and the Lower Volga regions due to less diversity of some ecological groups and mainly insufficient knowledge of charophytes from the regions except for Samara region. The species composition of charophytes from the region studied could be tentatively recognised as impoverished compared to the Upper Volga Region. Its low similarity with the Lower Volga Region could be explained with the absence of many characteristic species of southern chorotype. Chara vulgaris and C. globularis are the most common species in the study area. They could be recognised as generalists. A correction of species lists for the regional Red Data Books has been suggested. The protection of Chara contraria, C. papillosa, C. subspinosa, C. tomentosa, C. virgata, Nitella gracilis, N. mucronata has been recommended according to the criteria of the Red Data Book of the Russian Federation. Chara subspinosa seems to be a regionally extinct species. Karst and oxbow lakes and to a lesser extent inundated quarries and ponds could be recognised as the most important for charophyte species protection. Three important plant areas have been identified as essential for long-term persistence of stable charophyte populations: the National Park «Mariy Chodra» in the Republic of Mariy El, the regional sanctuary «Golubye Ozyora» in the Republic of Tatarstan and the regional natural monument «Ozero Goluboe» in Samara region.

The long-term and seasonal dynamics of the water level in the Rybinsk Reservoir has been studied for the period of 1947–2015. The dependence of the area of overgrowing of shallow waters (S) on the water-level fluctuations (Z) has been obtained: S = 30‒45e1.054Z. The overgrowing of open shallow waters is restrained by the hydrodynamic influence on the littoral zone, while, in the case of protected shallow waters, the limiting factor is the drying up of habitats of aquatic plants, which takes place at the end of the vegetation season. For different ecological groups, the calculated maximum and optimum areas of overgrowing vary from 10 to 100% of the total available shallow water area. Reserve areas suitable for the possible future distribution of plants vary from 40 to >90%. Results of the study show that, due to sharp long-term and annual fluctuations in water level, actual areas occupied by a higher aquatic vegetation are always significantly less than the calculated optimum and maximum areas. Under the current regime of reservoir regulation, its overgrowing will be maintained at a current level for a long time.

Plant infection with Agrobacterium rhizogenes leads to the development of a hairy root disease notable for the rapid agravitropic growth of roots on hormone-free nutrient media. In order to look into the interaction of A. rhizogenes with plants and assess opportunities of practical application of hairy root culture, new approaches to their production are elaborated. A method of bacterium-free and plasmid-free production of genetically modified roots (hairy roots) by means of biolistic transformation of leaf explants with a DNA fragment (size of 5461 bp) consisting of genes rolA, rolB, rolC, and rolD are proposed. In most cases, such transformation resulted in the emergence of only adventitious roots with transient expression of rol-genes, and the growth of such roots on hormone-free media ceased in 2–3 months in contrast to genuine hairy roots capable of unrestricted growth. Molecular analysis of different systems of target genes’ expression showed an important role of transgene rolC and host gene of cyclin-dependent protein kinase CDKB1-1 in the maintenance of rapid growth of hairy roots in vitro (in isolated cultures).

A historical review of the advent and improvement of the methods for detecting multilocus DNA polymorphism that do not require preliminary knowledge of the individual gene and complete genome sequences of eukaryotes is presented. The first group of these methods includes approaches based on the use of primers with arbitrary sequence (random priming). Another group of methods to detect DNA polymorphism is based on the use of primers that consist of short repetitive sequences having anchor nucleotides at the 5'- or 3'-ends that position the annealing sites of these primers (microsatellite priming). Another approach for revealing polymorphism that does not require knowledge of the DNA sequence is based on cleavage of total DNA by a combination of restriction endonucleases (random cleavage) accompanied by PCR amplification. Considerable attention is paid to the opportunities of using these approaches to detect DNA polymorphism in the form of converting the obtained data to digital format and creation of integrative databases for all organisms, regardless of the methods used.

Background. Triticum sinskajae A. Filat. et Kurk. was discovered in the early 70th in the last century at the regular reproduction in the Central Asian and Dagestan VIR-stations of T. monococcum samples. Materials and methods. The objects of the study were 4 species of diploid wheat Triticum urartu Thum. ex Gandil. (lines k-62477, k-62465), Triticum monococcum L. (lines k-20970, k-39471), Triticum boeoticum Boiss. (lines k-59161, k-28132, k-40118) and Triticum sinskajae A. Filat. et Kurk. (line k-48993). Results. We found differences between T. sinskajaeand T. monococcum in the variable region of the histone gene H3.2, and the RAPD analysis showed the presence of unique polymorphic loci in T. sinskajae. Conclusion. In gene ral, T. boeoticum, T. monococcum, and T. sinskajae are most likely to be closely related species of diploid wheat, whereas T. urartu is quite significantly different from them.

The peculiarities of root growth and stress tolerance of transgenic tobacco plants with constitutive expression of NtEXPA1 and NtEXPA5 genes, as well as plants with reduced expression of NtEXPA4 gene encoding α-expansins of Nicotiana tabacum, were studied during prolonged cultivation under conditions of drought, salinity, and low positive temperatures. Increased expression of expansin genes led to an increase in the growth rate and root length both under normal plant growth conditions and at 12°C and 50 mM NaCl. Increased expression of expansin genes influenced the changes in the fresh and dry mass of a shoot, leading to an increase in their exposure to hypothermia. Transgenic plants with a reduced level of NtEXPA4 expansin gene expression were characterized by a reduction in the fresh and dry weight of a shoot due to drought and low positive temperatures. The totality of the data obtained may indicate the involvement of NtEXPA1, NtEXPA4, and NtEXPA5 tobacco expansin genes in the regulation of growth under hypothermia, drought, and salinity.

Possible routes in which aquatic plants have spreaded across their vast ranges from ancestral areas and refugia still remain poorly known. We have chosen Eurasian yellow water-lilies (Nuphar Sm. sect. Nuphar, Nymphaeaceae) as a model group for a wide-scale phylogeographical study as they represent a common component of the continental freshwater flora. To elucidate the history of diversification of the section Nuphar, we sequenced nuclear ribosomal ITS and chloroplast intergenic spacers (trnH-psbA, trnL–trnF) from 117 localities from almost all the section area. Sequence data were analysed with a statistical parsimony approach using the network algorithm. We also incorporated data on morphological variation and pollen viability. The section Nuphar originated and diversified into several evolutionary lineages in Eastern Asia. Two lineages, represented by N. pumila and N. lutea, spread from the Russian Far East westwards to Siberia and further to Europe. Nuphar pumila also migrated from the Far East to North America (where it is referred to as N. microphylla). Nuphar lutea colonized deglaciated north-eastern Europe not only from the south, but also from the Siberian refugia. Nuphar lutea and N. pumila hybridize rarely in Eastern Europe and Asia and warrant species status. We provide the first evidence, based on a phylogeographical approach, for the origin and diversification of aquatic flowering plants in Eastern Asia. Our results indicate that phylogeographic analysis on the area-wide scale is one of the most efficient ways to deduce possible routes in which aquatic plants have spread across their total range from ancestral areas and refugia.

The expression level of the gene PtrXTH1 encoding xyloglucan endo-transglycosylase in the leaves of Populus tremula L. of wild-type and in response to exogenous phytohormones treatment was analyzed. The highest level of transcripts of PtrXTH1 was detected in young, intensively growing leaves of aspen. In young aspen leaves, the expression of PtrXTH1 was induced by cytokinins, auxins, and brassinosteroids. The content of PtrXTH1 transcripts increased under the constitutive expression of the PnARGOS-LIKE gene. Bioinformatic analysis of PtXTH1 putative promoter region in P. trichocarpa Torr. and A. Gray ex. Hook showed the presence of cis-regulatory elements associated with the regulation of growth and stress resistance. To determine the role of the gene under study, we also created transgenic tobacco plants with constitutive expression of the PnXTH1 gene (the ortholog of PtrXTH1 from the black poplar P. nigra). Transgenic tobacco plants were characterized by an increase in leaf size and fresh and dry weight of the aboveground part under normal growth conditions. When grown under conditions of salinization and drought, transgenic plants were distinguished by increased stress resistance due to the maintenance of cell expansion in roots and stems at a higher level and the ability to more effectively retain water in leaves compared with wild-type plants.

The genes of α-expansins of woody plants are of great interest for genetic engineering, since they can potentially be used to improve the tree growth parameters. In the flora of Russia, model woody plants for plant biotechnology are aspen (Populus tremula L.) and black poplar (Populus nigra L.). The objective of this study was to determine the role of α-expansin-encoding genes, aspen PtrEXPA3 and black poplar PnEXPA3, in the regulation and maintenance of woody plant growth. To achieve this goal, the PtrEXPA3 expression level were determined upon exogenous phytohormone treatment, the action of stress factors, and constitutive expression of the PnARGOS-LIKE gene. In addition, transgenic aspen plants with constitutive expression of the black poplar PnEXPA3 gene were generated, and their morphological analysis was carried out. The highest PtrEXPA3 mRNA level was detected in young intensely growing aspen leaves, and furthermore, expression of the gene was induced by exogenous cytokinins and auxins. In response to NaCl and constitutive expression of the PnARGOS-LIKE gene, the PtrEXPA3 mRNA level decreased. Transgenic aspen plants with constitutive PnEXPA3 expression were characterized by the decreased size of leaves, petioles, and internodes, as well as the increased size of leaf epidermal cells, while the stem size remained unchanged. Taken together, the data obtained enable the suggestion that the PtrEXPA3 and PnEXPA3 genes encode cytokinin- and auxin-regulated, leaf-specific expansins that are involved in the cell expansion.

The features of overgrowing of different types of protected shallow waters in the Ivankovo, Uglich, and Gorky reservoirs have been considered. The average degree of overgrowing increases in the following series: pocket-type shallow waters (37.3% of area), shallow waters behind islands (40.6), and bays (56.9). Helophytes contribute to the overgrowing of more than 50% of all types of protected shallow waters. The composition of plant community dominants of protected shallow waters of different types is very similar, because the reservoirs belong to the same cascade, are located in one climatic zone, and have similar ecotopes. The effect of morphometric parameters (area, volume, length, average width and depth) and their ratios (oblongness of water area, openness, and isolation) on the overgrowing of protected shallow water areas is expressed only at average values of these parameters and has an exponential form. The contribution of the area isolation to overgrowing is most significant (up to 55%).

Amaranth is a new and promising crop for the Russian climate, notable for its well-balanced amino acid composition. Yield increase using the methods of genetic engineering is a challenging task. We generated transgenic plants of amaranth with expression of the Arabidopsis thaliana ARGOS-LIKE gene under the control of the dahlia mosaic virus promoter. We achieved 1.4% transformation effectiveness. In comparison with wild-type amaranth, we observed a 21% increase in stem length, 79% increase in leaf length, and 190% increase in fresh weight of transgenic plants. It was shown that ARGOS-LIKE gene of A. thaliana along with the dahlia mosaic virus promoter can be used to increase primarily the green weight of shoot and leaf size of amaranth.

The ability to synthesize milk-clotting (rennet) proteinases was studied in eight strains of Irpex Lacteus basidiomycetes. It was found that the studied I. lacteus strains are characterized by different enzyme activities in their culture liquid. For I. lacteus strains 2425, 2426, and 2427, the maximum milk-clotting activity was detected during the exponential growth phase on the 15th day of cultivation on glucose–peptone medium. These I. lacteus strains are the most prospective milk-clotting enzyme producers for further research and practical application. I. lacteus strains 2421, 2422, 2423, 2424, and 2428 showed lower values of the enzyme activity and require additional research to determine the optimal culture conditions.

We identified a Populus nigra auxin-regulated gene involved in organ size (PnARGOS)-LIKE, encoding one organ size related protein in black poplar. It is homologous to AtARGOS and AtARGOS-LIKE genes of Arabidopsis thaliana. ABRE-like, G-box, GATA and I-box motifs were discovered in the promoter region of the poplar ARGOS-LIKE gene. In wild type aspen (Populus tremula) plants, an ortholog of the PnARGOS-LIKE gene (PtrARGOS-LIKE) was noticeably expressed in actively dividing and expanding young leaves and calli, whereas its mRNA content increased in response to exogenous 6-benzylaminopurine, 1-naphthaleneacetic acid, and 24-epibrassinolide. Expression of the PtrARGOS-LIKE gene was reduced under a salinity treatment. In addition, we generated transgenic tobacco and aspen plants with an up-regulated expression of the PnARGOS-LIKE gene. A constitutive expression of the gene contributed to an increase in size of stems and leaves of the transgenic tobacco plants. In the transgenic aspen, a constitutive expression of the PnARGOS-LIKE gene promoted an increase in the frequency of leaf initiations and in leaf length and area. The size of transgenic tobacco and aspen leaves increased due to the enlargement of individual cells. The results show the significance of the PnARGOS-LIKE gene for control of leaf initiation and organ growth by cell expansion in poplar.

Eight species of charophytes have been found in the vast area of the ubiquitous permafrost in Far North-East Asia (i.e. the Republic of Sakha (Yakutia), the Magadan Region, and the Chukotka Autonomous Area, Russia): Chara contraria, C. globularis, C. strigosa, C. virgata, Nitella flexilis, N. opaca, N. wahlbergiana and Tolypella canadensis. Charophytes are found in a variety of water bodies and watercourses in areas with various thicknesses of permafrost, within the boreal and subarctic climate zones. Charophyte habitats are mostly associated with the distribution of carbonate rocks. The number of species and their records decrease towards north and east mainly due to shortening of the vegetation period. The highest density of records of charophytes and their most northern records are in river valleys, where the topography and heating effect of the river mitigate the influence of climate and permafrost. This association can be used to model and predict charophyte distribution in periglacial areas during glaciation. Widespread eurytopic species with a flexible life cycle, Chara contraria and C. globularis, are found in valley water bodies due to their ability to withstand environmental variation associated with marked changes in water temperature and flood disturbance. Rare perennial species such as C. strigosa and Tolypella canadensis are represented in deep lakes with less variation in environmental conditions. This paper discusses the distribution, habitat and life history strategies of charophytes that exist in the severe conditions of the permafrost area in Far North-East Asia based on previously published and new data.

Ultrasonic fragmentation, which is a simple and convenient method for the mechanical degradation of DNA, is widely used in modern genome studies as one of the sample preparation steps. It has been recently found that the DNA breaks occur more often in the regions containing 5'-CG-3' dinucleotides. We studied the influence of the 5'-CG-3' dinucleotides on the efficiency of the 28S rRNA gene amplification during PCR with sonicated DNA of Mantis religiosa. It was shown that the amplification rate depends on the template length and the number of 5'-CG-3' dinucleotides. Amplification of the DNA regions with a higher 5'-CG-3' density is less efficient because of their higher sensitivity to ultrasound. The amount of the amplified DNA templates is inversely proportional to the 5'-CG-3'number.

The Nicotiana tabacum AINTEGUMENTA-like gene (NtANTL), encoding one of AP2/ERF transcription factors, is a putative ortholog of the AtANT gene from Arabidopsis thaliana. In wild-type tobacco plants, the NtANTL gene was expressed in the actively dividing young flowers, shoot apices, and calluses, while the level of its mRNA increased considerably after treatment with exogenous 6-benzylaminopurine, indoleacetic acid and 24-epibrassinolide. We found a positive correlation among the expression levels of NtANTL, cyclin NtCYCD3;1 and cyclin-dependent kinase NtCDKB1-1 genes, suggesting possible molecular links between AINTEGUMENTA and cell cycle regulators in tobacco plants. However, no correlation was observed between NtANTL, NtCYCD3;1 and NtCDKB1-1 expression levels in response to NaCl and ABA. These observations indicate that the transcription factor NtANTL was not involved in the regulation of the cellular response to salinity nor did it affect the expression of NtCYCD3;1 and NtCDKB1-1 when tobacco plants were exposed to salt stress and ABA. In addition, we generated transgenic tobacco plants with both up-regulated and down-regulated expression of the NtANTL gene. Constitutive expression of the NtANTL gene contributed to an increase in the size of leaves and corolla of transgenic plants. Transgenic plants with reduced expression of the NtANTL gene had smaller leaves, flowers and stems, but showed a compensatory increase in the cell size of leaves and flowers. The results show the significance of the NtANTL gene for the control of organ growth by both cell division and expansion in tobacco plants.

Screening of nodule bacteria (rhizobia) forming symbiotic relationships with legumes has been performed in order to isolate strains resistant to cadmium ions in a wide range of concentrations (6-132 mg/kg). The effect ofcadmium salts (6, 12, 24 mg/kg) on the legume-rhizobium symbiosis ofthe pea Pisum sativum L. with Rhizobium leguminosarum and of the fodder galega Galega orientalis Lam. with Rhizobium galegae has been studied under experimental laboratory conditions. No statistically significant differences have been revealed in the growth and biomass of plants with regard to the control in the range of concentrations given above. However, it was found that cadmium inhibited nodulation in P. sativum and stimulated it in G. orientalis.

DNA analysis of nimplex biological objects (wastewater, soil, archaeological and forensic samples, etc.) is currently of great interest. DNA of these objects is characterized by low suitability for research due to the violation of its integrity and chemical structure; thus, the detection of specific nucleic acid fragments can be achieved by PCR with contiguous primers. In this paper, we present the results that clarify the specific characteristics of PCR with abutting primers. The 3'-ends of these primers are annealed at adjacent nucleotides of complementary chains of DNA target. It has been shown that the proximity of primers enables the formation of specific reaction products with a higher sensitivity and less reaction time. Using artificially damaged DNA and DNA from the soil we demonstrated that the abutting primers provide assured detection of specific DNA fragments. The results of this work may be taken into account in PCR with degraded (fragmented) DNA.

Transgenic tobacco plants expressing Arabidopsis thaliana ARGOS and ARGOS-LIKE genes under the control of the chalcone synthase promoter of Petunia hybrida L., as well as the estradiol inducible XVE system, have been obtained. The part of transgenic plants with flower-specific expression of the target genes was characterized by increased flower size, caused by an increase in cell size and quantity in the case of the ARGOS gene and by a stimulation of cell growth via stretching in the case of the ARGOS-LIKE gene. An enhanced expression level of the NtEXPA1, NtEXPA4 genes encoding expansins, NtEXGT gene encoding endo-xyloglucan transferase, and the AINTEGUMENTA-like gene was detected in the flowers of transgenic tobacco plants. In the case of inducible expression of ARGOS and ARGOS-LIKE genes, an increase in leaf, stem and flower size was revealed in several lines of transgenic plants as compared to control. Expression of the ARGOS gene also affected cell number and size in this case, while the ARGOS-LIKE gene mainly influenced cell size via stretching. Inducible expression of the ARGOS gene in flowers mainly provided an enhanced containment of AINTEGUMENTA-like mRNA, while ARGOS-LIKE gene expression resulted in the activation of NtEXPA1 and NtEXGT genes.

The tobacco plant genes NtEXPA1 and NtEXPA4 encode the α-expansin proteins involved in the regulation of cell growth and extension. We examined the levels of expression of these genes in various plant organs and under the effect of exogenous phytohormones. The highest levels of NtEXPA1 expression were registered in the terminal bud and in the young growing leaves and flowers. NtEXPA1 expression ceased once the leaves stopped growing. The NtEXPA4 gene showed a similar expression profile, except for higher levels of mRNA in the leaves. In young leaves located near the terminal bud, high levels of NtEXPA1 and NtEXPA4 are induced by auxins. In the lower leaves, expansin expression is differentially regulated by brassinosteroids, which inhibit NtEXPA1 and upregulate NtEXPA4. We further showed that expression of the transgenic ARGOS-LIKE results in upregulation of NtEXPA1 and a reduction in the NtEXPA4 mRNA. In turn, overexpression of NtEXPA1 resulted in an increased size of the leaves and stems because of the larger size of the individual cells.

Aegagropila linnaei (Chlorophyta, Cladophoraceae) is reported for the first time for the territory of the Udmurt Republic from Pazelinskiy Bay of Izhevsk Reservoir. The habitat description and morphological characteristics of the alga are provided. It is suggested that the species is threatened in the habitat. A. linnaei is recommended to include in the Red Data Book of the Udmurt Republic.

Transgenic tobacco plants expressing the fragments of the ARGOS and NtEXPA4 genes in antisense orientation have been created. Eleven lines of transgenic plants were investigated and five of them were characterized by a decrease in the sizes of the leaves and flowers as compared to control. Stem sizes decreased when only the NtEXPA4 gene fragment was used. The organ size of the experimental plants decreased because of a reduction in the level of both cell division and cell expansion. Two lines of transgenic tobacco plants expressing the part of the ARGOS gene in antisense orientation were characterized by a reduction in the level of the NtEXPA1 and NtEXPA4 gene expression.