The increasing availability of Single Nucleotide Polymorphisms (SNPs) discovered by Next Generation Sequencing will enable a range of new genetic analyses in crops, which was not possible before. Concomitantly, researchers will face the challenge of handling large data sets at the whole-genome level. By grouping thousands of SNPs into a few hundred haplotype blocks, complexity of the data can be reduced with fewer statistical tests and a lower probability of spurious associations. Owing to the strong genome structure present in breeding lines of most crops, the deployment of haplotypes could be a powerful complement to improve efficiency of marker-assisted and genomic selection. This review describes in brief the commonly used approaches to construct haplotype blocks and some examples in animals and crops are cited where haplotype-based dissection of traits were proven beneficial. Some important considerations and facts while working with haplotypes in crops are reviewed at the end.

The state of the art in the evolution of plant viruses allows the genetic foundations of antiviral immunity in higher (including the most important crops) plants to be categorized as one of the most pressing issues of genetics and selection. According to the endosymbiotic theory, mitochondria descended from alphaproteobacteria that had been absorbed but not degraded by the host cell. The discovery of CRISPR-Cas systems (clustered regularly interspaced short palindromic repeats (CRISPR)-associated proteins), which implement the adaptive immunity function in prokaryotes, raises the question whether such a mechanism of antiviral protection could be caught up by evolution and used by representatives of eukaryotes (in particular, plants). The purpose of this work was to analyze the complete sequences of nuclear, mitochondrial, and chloroplast genomes of Arabidopsis thaliana in order to search for genetic elements similar to those in CRISPR-Cas systems of bacteria and archaea. As a result, in silico methods helped us to detect a locus of regularly intermittent short direct repeats in the mitochondrial genome of A. thaliana ecotypes. The structure of this locus corresponds to the CRISPR locus of the prokaryotic adaptive antiviral immune system. The probable connection between the locus found in the mitochondrial genome of the higher plant and the function of adaptive immunity is indicated by a similarity between the spacer sequences in the CRISPR cassette found and the genome of Cauliflower mosaic virus affecting Arabidopsis plants. Sequences of repeats and spacers of CRISPR cassettes in Arabidopsis C24 and Ler lines are perfectly identical. However, the locations of the CRISPR locus in the mitochondrial genomes of these lines differ significantly. The CRISPR cassette in the Col-0 line was found to be completely broken as a result of four deletions and one insertion. Although cas genes were not detected in the mitochondrial genome of the studied Arabidopsis ecotypes, their presence was detected in the nuclear genome. Both cas genes and numerous CRISPR cassettes were found on all the five chromosomes in the nuclear genome of the Col-0 ecotype. The results suggest the existence of a system of adaptive immunity in plants, which is similar to the CRISPR immunity of bacteria and archaea.

Fifty-three species of perennial grasses in the genus Elymus L. (Poaceae), which are widespread in Russia, are generally assumed to have three haplome combinations: StH, StY and StHY. The StH-genome species, endemic to Russia, remain the least studied. R. Mason-Gamer and co-authors have previously shown in a series of studies that a molecular phylogenetic analysis of the low-copy gene waxy (GBSS1) sequences significantly complements cytogenetic data on the genomic constitution and evolutionary relationships among both North American and Asian species of the genus Elymus. To determine the species’ genomic constitution and to evaluate the level of phylogenetic differentiation, we examined the GBSS1 gene in 18 species of Elymus from Siberia and the Russian Far East, including the fol- lowing 14 endemics: E. charkeviczii, E. jacutensis, E. kamczadalorum, E. komarovii, E. kronokensis, E. lenensis, E. macrourus, E. margaritae, E. subfibrosus, E. sajanensis, E. transbaicalensis, E. peschkovae, E. uralensis, and E. viridiglumis.PCR amplification products of GBSS1 gene fragments (including exons 9–14) were cloned and 6–8 clones per accession were sequenced. It appears that all the species studied have St and H subgenomic gene variations. The most significant differences between the subgenomic variants St and H were found in intron 13. The H subgenome contains a 21-bp-long deletion in intron 13 in all Elymus genotypes, probably derived from a common ancestor of the H and P genomes. Instead of this deletion, all St subgenomes have a relatively conservative sequence similar to that of the genus Pseudoroegneria, whose ancestor is considered to be the donor of the modern St subgenome for all Elymus species. Cluster phylogenetic analysis revealed differentiation in St and H subgenome sequences into two evolutionary variants: St1 vs. St2 and H1 vs. H2, respectively. Variants of the St and H subgenomes were found homologous to various modern species of the ancestral genera Pseudoroegneria and Hordeum: St1 to P. strigosa, St2 to P. spicata, H1 to H. jubatum, and H2 to H. californicum. The details of the relationships between Russian and North American species of the genus, as well as a number of microevolutionary interconnections in the group of boreal endemic species of Siberia and the Russian Far East were revealed. The new results obtained here are essential for the development of a phylogenetically oriented taxonomic system for the genus Elymus.

Synthetic recombination form RS7 (BBAAUS), in which the first two genomes, A and B, originate from common wheat, and the third recombinant genome consists of Aegilops speltoides (S) and Ae. umbellulata (U) chromosomes, was obtained from crossing synthetic forms Avrodes (BBAASS) and Avrolata (BBAAUU). Resistant to leaf rust, yellow rust and powdery mildew, introgression lines have been obtained from backcrosses with the susceptible varieties of common wheat Krasnodarskaya 99, Fisht and Rostislav. PCR analysis showed the presence of amplification fragments with marker SCS421 specific for the Lr28 gene in the line 4991n17. The cytological study (С-banding and FISH) of 14 lines has revealed chromosomal modifications in 12 of them. In most cases, the lines carry translocations from Ae. speltoides, which were identified in chromosomes 1D, 2D, 3D, 2B, 4B, 5B and 7B. Also, lines with the substituted chromosomes 1S (1B), 4D (4S), 5D (5S) and 7D (7S) were identified. Lines that have genetic material from Ae. speltoides and Ae umbellulata at once were revealed. In the line 3379n14, translocations in the short arm of chromosome 7D from Ae. umbellulata and chromosomes 5BL, 1DL, 2DL from Ae. speltoides were revealed. The line 4626p16 presumably has a translocation on the long arm of chromosome 2D from Ae. umbellulata and the T7SS.7SL-7DL translocation from Ae. speltoides. The T1DS.1DL-1SL and T3DS.3DL-3SL translocations from Ae. speltoides, and T2DS.2DL-2UL and T7DL.7DS-7US from Ae. umbellulata have been obtained for the first time. These lines may carry previously unidentified disease resistance genes and, in particular, leaf rust resistance genes from Ae. speltoides and Ae. umbellulata.

The lack of clear morphological markers of cotton chromosomes contributed to the development of an unconventional method for marking chromosomes using translocations. Today, tester translocation cotton lines represent the most complete set of cytological markers. The results of cytogenetic analysis of F1 hybrids obtained from crosses of monosomic cotton lines with translocation lines with identified chromosomes are presented. Cytogenetic identification and numbering of univalent chromosomes in 25 monosomic lines of the cytogenetic collection of the National University of Uzbekistan allowed us to establish the following univalent occurrences: chromosome 2 in four monosomic lines, chromosome 4 in 15 lines, chromosome 6 in four lines, chromosome 7 of the At-subgenome in one line and chromosome 18 of the Dt-subgenome in one line. The remaining 21 lines were duplicates of three non-homologous chromosomes. All monosomic lines identified were characterized by differences in univalent sizes, meiotic index, number of tetrads with micronuclei, pollen fertility, frequency of monosomy in the progeny, and a complex of morphological characters associated with the monosomy of the chromosome identified. Despite differences in the genotypic environment and methods for producing monosomics in the two cotton collections, there is a surprising coincidence of data suggesting a higher frequency of chromosomes 2, 4 and 6 occurring as monosomics, while the other chromosomes of the set occur as monosomics at a much lower frequency, and eight nonhomologous chromosomes (5, 8, 13 of the At-subgenome and 14, 15, 19, 22 and 24 of the Dt-subgenome of cotton) never do.

The development of bread wheat introgressions with alien genetic material from cultural and wild Triticeae species is an effective method for expanding the wheat gene pool necessary for breeding. To date, numerous collections of introgressions as substitutions and chromosome modifications have been obtained; however, the creation and study of wheat with new valuable traits still remain an important line of research. Rye Secale cereale L., whose chromosomes carry genes that control valuable economic and biological characteristics and properties, is widely used to produce new wheat forms. In this study, a wheat-rye translocation obtained by backcrossing the wheat-rye disomic-substitution line 2R(2D)1 with the variety Novosibirskaya 67 was characterized. The chromosomal composition of karyotypes was studied using fluorescent in situ hybridization and C-banding. Two centric translocations, derived from two long arms of chromosomes 2D and 2R, T2DL.2RL, were identified, the remaining 40 wheat chromosomes did not undergo modifications. Meiosis in the lines was stable. Chromosomes T2DL.2RL formed bivalents in all meiocytes, which confirmed their homology. The morphological characteristics of the spike in the T2DL.2RL line and Novosibirskaya 67 did not differ. A comparative analysis of productivity between the T2DL.2RL translocation line and the parental forms, Novosibirskaya 67 and the 2R(2D)1 line, was carried out. The T2DL.2RL line is inferior to Novosibirskaya 67 in all characters with different confidence levels. The productivity characters of the 2R(2D)1 line exceeded or did not differ from those of T2DL.2RL, however, the mass of 1000 grains was significantly lower. The results showed the effect of the T2DL.2RL translocation on the trait “plant height”. This character was significantly lower than that of Novosibirskaya 67 in two vegetation periods. Consequently, the T2DL.2RL translocation reduces plant height and productivity.

The fungus Stagonospora nodorum Berk. is the causative agent of Septoria nodorum blotch (SNB) of wheat. The most important factors of Stagonospora nodorum virulence include numerous fungal necrotrophic effectors (NEs) encoded by SnTox genes. They interact with the matching products of host susceptibility genes (Snn). SnTox-Snn interactions are mirror images of classical gene-for-gene interactions and lead to the development of disease. We have studied the SnTox3-Snn3 interaction, resulting in the development of infection on leaves and formation of extensive lesions. The mechanism of SnTox3 action is likely to be linked to the regulation of redox metabolism and the influence on ethylene synthesis in the wheat plants, although the molecular mechanisms are not fully unveiled. To characterize the SnTox3-Snn3 interaction, we used S. nodorum isolates differing in the expression of the NEs genes SnTox3 (SnB (Tox3+), Sn4VD (Tox3–)) and two soft spring wheat (Triticum aestivum L.) cultivars, contrasting in resistance to the SNB agent and differing in the allelic composition of the susceptibility locus Snn3-B1: Kazakhstanskaya 10 (susceptible) and Omskaya 35 (resistant). We carried out a comparative assessment of the transcriptional activity patterns of genes responsible for ethylene biosynthesis (TaACS1, TaACО) and signaling pathway (TaEIL1, TaERF1) by real-time PCR and estimated the redox state of wheat plants infected with different isolates of S. nodorum by spectrometry. The induction of ethylene biosynthesis and signaling has been shown to result from gene-for-gene interaction between Snn3-B1 and SnTox3. The results of plant redox status estimation showed that ethylene inhibited accumulation of hydrogen peroxide in SnTox3-sensitive genotypes by regulating the operation of various pro-/antioxidant enzymes at the transcriptional and posttranslational levels. Our results suggest that NE SnTox3 influences ethylene biosynthesis and signaling, thereby regulating redox metabolism in infected wheat plants as necessary for successful host colonization at the initial phases of infection, which ultimately leads to extensive lesions due to fast pathogen reproduction.

The greenbug aphid Schizaphis graminum Rond. causes a significant loss of the grain harvest. Therefore, to improve plant resistance to aphids is one of the topical tasks. The problem of creating varieties resistant to phloem-feeding insects is quite urgent, since the mechanisms procuring the resistance of plants to insects are not fully understood. Nevertheless, modern literature describes some mechanisms associated with changes in the redox state of colonized plants. Besides, attention is being increasingly focused on the study of mechanisms that underlie inducible resistance to aphids in wheat and are regulated by hormonal signaling systems. To detect connections among the redox status, indicators of resistance (antibiosis and endurance) of wheat plants to the pest, and induction of the jasmonate (JA) and salicylate (SA) signaling pathways, we studied accessions of three species of wheat plants – Triticum aestivum L., T. monococcum., and T. timopheevii Zhuk.– infested with S. graminum greenbugs by physiological, biochemical, and molecular methods. Analysis of antibiosis and endurance showed that T. timopheevii k-58666 and T. monococcum k-39471 were resistant to S. graminum, the latter accession being the most enduring. High hydrogen peroxide contents and high peroxidase activities were detected in the resistant plants. We investigated the expression of genes encoding PR proteins, including markers and regulators of the salicylate (TaRboh, TaPAL, Tapr1, TaPrx) and jasmonate (TaPI, TaLOX, TaPrx) signaling pathways. At the early stage of infestation in the susceptible T. aestivum variety Salavat Yulaev, the expression of only jasmonate-dependent genes was activated in response to plant damage. In the resistant T. timopheevii accession k-58666, expression of only salicylate-dependent genes was activated, while the aphid reproduction was practically absent. In the resistant T. monococcum accession k-39471, expression was activated in both the salicylate-dependent and jasmonate-dependent gene groups. We assume that the oxidative burst in the resistant forms of wheat was induced via the activation of the SA signaling pathway, which was of crucial importance in the further cascade of chemical reactions leading to the development of resistance.

Viral diseases annually cause significant crop losses and significantly reduce the quality of products, including potatoes, some of the most important crops. Currently, viruses cannot be controlled with chemical pesticides, since known antiviral compounds are teratogenic and hazardous to people’s health. Biocontrol agents based on endophytic microorganisms may be an alternative to them. Many strains of Bacillus produce ribonucleases (RNases). Our laboratory possesses a collection of bacteria that produce various metabolites and have RNase activity. The results showed that the inoculation of potato with B. subtilis 26D and B. thuringiensis increased the grain yield by 32–43 %. In addition, the treatment of potato plants with Bacillus spp. significantly reduced the infection of potato plants with virus M. The prevalence of the disease in potato plants was significantly reduced from 60 % in the control to 18 % (B. subtillis 26D) and 25–33 % (B. thuringiensis) in the inoculated plants. Similarly, the infection index decreased from 14 in the control to 1 in the inoculated plants. The further study of molecular mechanisms related to bacterial induction of plant defense reactions in response to viral infections will lead to a better understanding of stress resistance problems. The endophytic microorganisms studied in this report may become the basis for the creation of biological agents for plant protection.

Tan spot caused by the fungus Pyrenophora tritici-repentis is an important leaf spot disease in wheat growing areas throughout the world. The study aims to identify wheat germplasm resistant to tan spot based on phytopathological screening and molecular marker analysis. A collection of 64 common wheat germplasms, including cultivars and breeding lines from Kazakhstan and CIMMYT, was assessed for tan spot resistance in greenhouse conditions and characterized using the Xfcp623 molecular marker, diagnostic for the Tsn1 gene. All wheat cultivars/lines varied in their reaction to tan spot isolate race 1, ranging from susceptible to resistant. Most accessions studied (53 %) were susceptible to Ptr race 1. Spring wheat cultivars were more susceptible to race 1 than winter wheat cultivars. As a result of genotyping, an insensitive reaction to Ptr ToxA was predicted in 41 wheat cultivars (64 %). The tsn1 gene carriers identified included 27 Kazakhstani and 14 CIMMYT cultivars/lines, demonstrating insensitivity to Ptr ToxA. The majority of the Tsn1 genotype were sensitive to race 1 and showed susceptibility to the pathogen in the field. Disease scores from seedling stage positively correlated with field disease ratings. Of particular interest are 27 wheat accessions that demonstrated resistance to spore inoculation by Ptr race 1, were characterized by insensitivity to ToxA and showed field resistance to the pathogen. The results of this study will contribute to wheat breeding programs for tan spot resistance with Marker Assisted Selection using the closely flanking markers.

Leaf rust (LR) and stem rust (SR) are harmful fungal diseases of bread wheat (Triticum aestivum L.). The purpose of this study was to identify QTLs for resistance to LR and SR that are effective in two wheat-growing regions of Kazakhstan. To accomplish this task, a population of recombinant inbred lines (RILs) of ‘Pamyati Azieva × Paragon’ was grown in the northern and southeastern parts of Kazakhstan, phenotyped for LR/SR severities, and analyzed for key yield components. The study revealed a negative correlation between disease severity and plant productivity in both areas. The mapping population was genotyped using a 20,000 Illumina SNP array. A total of 4595 polymorphic SNP markers were further selected for linkage analysis after filtering based on missing data percentage and segregation distortion. Windows QTL Cartographer was applied to identify QTLs associated with LR and SR resistances in the RIL mapping population studied. Two QTLs for LR resistance and eight for SR resistance were found in the north, and the genetic positions of eight of them have matched the positions of the known Lr and Sr genes, while two QTLs for SR were novel. In the southeast, eight QTLs for LR and one for SR were identified in total. The study is an initial step of the genetic mapping of LR and SR resistance loci of bread wheat in Kazakhstan. Field trials in two areas of the country and the genotyping of the selected mapping population have allowed identification of key QTLs that will be effective in regional breeding projects for better bread wheat productivity.

Flax (Linum usitatissimum L.) is used for the production of textile, oils, pharmaceuticals, and composite materials. Fusarium wilt, caused by the fungus Fusarium oxysporum f. sp. lini, is a very harmful disease that reduces flax production. Flax cultivars that are resistant to Fusarium wilt have been developed, and the genes that are involved in the host response to F. oxysporum have been identified. However, the mechanisms underlying resistance to this pathogen remain unclear. In the present study, we used transcriptome sequencing data obtained from susceptible and resistant flax genotypes grown under control conditions or F. oxysporum infection. Approximately 250 million reads, generated with an Illumina NextSeq instrument, were analyzed. After filtering to exclude the F. oxysporum transcriptome, the remaining reads were mapped to the L. usitatissimum genome and quantified. Then, the expression levels of cinnamyl alcohol dehydrogenase (CAD) family genes, which are known to be involved in the response to F. oxysporum, were evaluated in resistant and susceptible flax genotypes. Expression alterations in response to the pathogen were detected for all 13 examined CAD genes. The most significant differences in expression between control and infected plants were observed for CAD1B, CAD4A, CAD5A, and CAD5B, with strong upregulation of CAD1B, CAD5A, and CAD5B and strong downregulation of CAD4A. When plants were grown under the same conditions, the expression levels were similar in all studied flax genotypes for most CAD genes, and statistically significant differences in expression between resistant and susceptible genotypes were only observed for CAD1A. Our study indicates the strong involvement of CAD genes in flax response to F. oxysporum but brings no evidence of their role as resistance gene candidates. These findings contribute to the understanding of the mechanisms underlying the response of flax to F. oxysporum infection and the role of CAD genes in stress resistance.

The genus Allium L. (Amaryllidaceae), the most numerous among monocotyledonous plants, includes such economically important vegetable crops as onion (A. cepa), garlic (A. sativum) and leek (A. porrum). Leek has a high taste and proven valuable dietary properties and is one of the most popular vegetable crops in Western Europe. Despite a high importance of leek as a vegetable, this species is rarely the subject of molecular genetic studies. The genetic diversity of leeks has never been studied before. Therefore, in this work, we studied the nuclear variability (AFLP) and the chloroplast (nucleotide sequence analysis) genomes using a broad sample. For this work, 65 leek accessions were selected from the collection of the Scientific Center of Vegetable Crops, which included varieties of domestic and foreign breeding. As a result of an AFLP analysis and processing of the DNA spectra obtained, 760 fragments were identified, of which 716 were polymorphic for the leek accessions being analyzed. The calculated genetic distances between the leek samples varied from 0.4 to 0.76, which is comparable to the intraspecific polymorphism of related Allium species (onions, garlic). Analysis of the genomic structure with STRUCTURE 2.3.4 divided the leek samples into seven groups, which generally coincides with the clustering of these samples. To assess the variability of the chloroplast genome, nine sites of the chloroplast genome were sequenced in the leek samples, both non-coding (intergenic spacers rpl32-trnL, ndhJ-trnL, and intron rps16 gene), and protein coding genes (psaA, psaB, psbA, psbB, psbE, petB). The analysis of the sites of the leek chloroplast genome revealed an extremely low level of their polymorphism, only six SNPs were detected in the studied sequences with a total length of about 10,500 bp. Thus, as a result of this work, a high level of polymorphism of the leek nuclear genome was revealed, while the polymorphism of the chloroplast genome was extremely low.

This article presents the results of a molecular marker-assisted study of allelic variants of Wx genes in common wheat (Triticum aestivum L.) lines. The study was carried out as part of the work on the transfer of null alleles of the genes Wx-A1, Wx-B1, and Wx-D1 to the varieties of soft wheat and creation of breeding material with modified activities of the main enzymes involved in amylose biosynthesis. The lines were obtained at the Department of Breeding and Seed Production of Wheat and Triticale, National Center of Grain named after P.P. Lukyanenko, by crossing mutant forms carrying inactive (null) alleles of genes Wx-A1, Wx-B1, and Wx-D1 with bread wheat cultivars. The molecular markers selected for the study allowed identification of valuable breeding material carrying both single null alleles of Wx genes and their combinations in its genome. A combination of two null alleles (Wx-A1b + Wx-D1b) was detected in 30 lines. The presence of three null alleles (Wx-A1b + Wx-B1b + Wx-D1b), which corresponded to fully Wx wheat, was found in one line. We selected 37 lines that combined the presence of the Wx-B1e allele with the Wx-A1b and Wx-D1b null alleles. The Wx-A1b + Wx-B1e combination was identified in 26 lines, and 24 lines carried the combination of alleles Wx-B1e + Wx-D1b. The mutant forms PI619381, PI619384, and PI619386 were identified as carriers of the functional Wx-B1e allele. The Wx-A1b and Wx-B1e alleles could have been transferred to the studied lines from the donors used or from the Starshina and Korotyshka varieties, respectively. The mutant forms used in the crosses are donors of the Wx-B1b and Wx-D1b alleles. The use of molecular markers chosen by us for identification of the allelic state of the Wx-A1, Wx-B1, and Wx-D1 genes can provide grounds for marker-assisted selection for this trait. Selected lines found to possess null alleles of the Wx genes are applicable in breeding programs aimed at the improvement of technological qualities of grain and raise of bread wheat varieties with modified starch properties.

Alleles of the genes, conferring a dwarfing phenotype, play a crucial role in wheat breeding, as they not only reduce plant height, ensuring their resistance to lodging, but also have a number of positive and negative pleiotropic effects on plant productivity. Durum wheat carries only two subgenomes (A and B), which limits the use of the D-subgenome genes and requires the expansion of the arsenal of dwarfing alleles and the study of their effects on height and agronomically important traits. We studied the effect of the gibberellin-insensitive allele Rht-B1p in the B2F2:3 families, developed by crossing Chris Mutant /#517//LD222 in a field experiment in Moscow and Krasnodar. In our experiments, plants homozygous for Rht-B1p were shorter than those homozygous for the wild-type allele Rht-B1a by 36.3 cm (40 %) in Moscow and 49.5 cm (48 %) in Krasnodar. In the field experiment in Krasnodar, each plant with Rht-B1p had one less internode than any plant with Rht-B1a, which additionally contributed to the decrease in plant height. Grain weight per main spike was lower in plants with Rht-B1p than in plants with Rht-B1a by 12 % in Moscow and by 23 % in Krasnodar due to a decrease in 1000 grain weight in both regions of the field experiment. The number of grains per main spike in plants with Rht-B1p was higher in comparison to that with Rht-B1a by 6.5 % in Moscow due to an increase in spikelet number per main spike and by 11 % in Krasnodar due to an increase in grain number per spikelet. The onset of heading in plants with Rht-B1p in comparison with the plants with the wild-type allele Rht-B1a was 7 days later in Krasnodar. The possibility and prospects for the use of Rht-B1p in the breeding of durum wheat are discussed.

Several species of the genus Miscanthus Anderss. (elephant grass) characterized by a high rate of growth of the aboveground vegetative mass are currently in the focus of attention due to their high practical application as a source of bioethanol and cellulose. The main goals of this study were: (1) molecular genetic identification and (2) histochemical analysis of the genus Miscanthus Anderss. species in the collection of Central Siberian Botanical Garden SB RAS in order to identify the most perspective and technically valuable individuals. To study the collection of Miscanthus samples, a multi-disciplinary approach was applied. To collect the samples of different species from native habitats, traditional systematic and geobotanical methods (comparative morphological and phytocenological) were used. According to the results of the ISSR-analysis, 16 samples of three Miscanthus species were divided into two clades: Sinensis and Sacchariflorus, the former including two subclades. For the samples of M. purpurascens_I and II, a hybrid origin of this species was confirmed by ISSR data. The molecular data obtained from the study allowed us to hypothesize that the samples involved in the subclade I of the Sinensis clade could be used as donors of resistance to adverse environments, and the samples of the subclade II, as donors of high biomass productivity. Based on histochemical analysis, sclerenchyma cells were characterized by the most lignin-rich thickened membranes, so the most appropriate direction in Miscanthus selection should be based on identification and using less lignin-containing samples.

Here we provide a scientific justification and experimental support for the choice of easily renewable cellulosic feedstock Miscanthus sacchariflorus (Maxim.) Hack. in order to obtain high-quality nutrient broths therefrom for bacterial cellulose biosynthesis. The plant life-forms promising for breeding were screened under introduction conditions at the Central Siberian Botanical Garden, SB RAS, and this study was thus aimed at investigating the full and reduced ontogenetic patterns; cellulose and noncellulosic contents, including lignin; and duraminization of vegetative (feedstock source) organs throughout the seasonal development. The full ontogenetic patterns of the plants grown from seeds that had been collected in native habitats were compared to show that M. sacchariflorus and M. sinensis Anderss. accessions are distinguished by longer being at the most vulnerable developmental stages: seedlings and plantlets. Hence, it is preferable to cultivate seedlings on protected ground, and plantations are advisable to establish with more stable cloned vegetative material. The chemical compositions of the whole plant, leaf and stem separately, from seven M. sacchariflorus harvests were examined to reveal a rise in cellulose content and a drop in noncellulosic content with plantation age. The Miscanthus stem was found to contain more cellulose than the leaf, regardless of the plant age. The overall cellulose content was 48−53 %, providing a rationale for studies of bacterial cellulose biosynthesis in a M. sacchariflorusderived nutrient medium. Since high lignin content is undesirable for technological processes concerned with biosynthesis of bacterial cellulose, we performed histochemical assays of transverse sections of the culms to monitor the seasonal course of lignification. Our results suggest that the specific time limits for harvesting the aboveground biomass as a feedstock be validated by histochemical data on the seasonal course of lignification of M. sacchariflorus sprouts. To sum up, the examined chemical composition of M. sacchariflorus grown in the Siberian climate conditions demonstrated its prospects as a source of glucose substrate, the basic component of good-quality nutrient media for biosynthesis of bacterial cellulose.

Galactomannan (gum), a water-soluble polysaccharide, is widely used as a gelling agent in liquids, including in the oil and gas industry for hydraulic fracturing. The most effective source of this valuable plant material is seeds of guar (Cyamopsis tetragonoloba (L.) Taub.), a legume crop new for Russia. Although in recent years progress has been made in the selection of guar varieties adapted to the conditions of the Russian Federation, the question of the most appropriate region for the cultivation of this crop remains open. The purpose of the study was to investigate how a region and technology of guar cultivation can affect the main indicators of the final target product: the content and viscosity of guar gum extracted from the seeds of various guar genotypes. To understand this, ecogeographical tests of 13 guar accessions from the VIR collection were conducted at the experimental stations of the Vavilov Institute (VIR), where climatic conditions correspond to the temperature requirements of the crop. To compare the properties of gum extracted from the seeds of various genotypes, a fast-tracked laboratory method was suggested allowing gum extracts to be obtained for assessing their viscosity. The method allows fast screening of the breeding material and selecting guar genotypes with beneficial properties of guar gum which are in demand by the oil industry. Applying the fast laboratory method for assessing the properties of gum in seeds of 13 guar varieties showed that the content and viscosity of gum of the same variety vary greatly depending on growing conditions. The same set of 13 guar accessions was grown in 2018 at the Volgograd, Astrakhan, Dagestan and Kuban VIR experimental stations. As a result, the maximum viscosity values were obtained for the seeds reproduced at the Astrakhan region, where the guar was grown on irrigated lands. On the other hand, the maximum gum content in the seeds of all accessions was recorded when they were grown in the Volgograd region. The results showed that the guar gum extracted from seeds of guar plants grown in the Russian Federation can be used as a gelling agent in the processes of intensification of oil production by the method of hydraulic fracturing. This experience is new to the Russian Federation.