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The use of modern methods for assessing the genotypic diversity of breeding material is effective in crop improvement. Interpretation of the results of a study of the fatty acid biochemical composition in seeds of hemp (Cannabis sativa L.) accessions is one of important stages in breeding oilseed varieties, since hemp possesses a unique fatty acid composition (FAC) among other oilseed crops in Russia. Studies of regularities in formation of seed oil FAC and the principal component analysis (PCA) of fatty acid contents have scientific significance and practical value for ensuring the acceleration of oilseed variety breeding aimed at improving quality and biological activity of oil. The use of PCA can be an effective in achieving this goal. The fatty acid profile of oil has been evaluated at the N.I. Vavilov Institute of Plant Genetic Resources in 25 hemp accessions from the VIR hemp collection. Local and industrial hemp varieties and breeding material of the Middle Russian ecotype were grown in Penza Province with a temperate continental climate on meadow-black soils of the Middle Volga Region of Russia. The seed oil FAC was studied using gas-liquid chromatography with mass spectrometry on an Agilent 6850 chromatograph. The results were processed using the UniChrom and AMDIS software. High content of omega-3 stearidonic fatty acid was found in accessions k-205 from Ukraine (1.23%) and k-168 from Russia (0.87%); that of α-linolenic acid in k-168 from Russia (0.82%) and k-224 from GDR (0.39%); of linoleic acid in k-154 (67.29%), k-360 (66.24%), and k-150 (64.58%) (all three from Russia); of γ-linolenic acid in k-88 from Russia (2.43%) and k-211 from GDR (1.92%). It has been established that the formation of hemp seed oil FAC is a multifactorial process. The main factor determined 27.8% of the variability. The presence of both positive and negative factor loadings was revealed. The highest factor loading for the variance of a complex of characters of the oil FAC is on the main factor, i.e. linoleic acid (+0.73). In relation to this acid, negative loadings were detected for myristic acid (−0.81), lauric acid (−0.78), palmitoleic acid (−0.72), and oleic acid (−0.72). The content of bioactive omega-6 diunsaturated linoleic acid was negatively associated with the content of omega-9 monounsaturated oleic acid, as well as with the content of polyunsaturated omega-6 γ-linolenic, omega-3 stearidonic, and omega-3 α-linoleic acids. The obtained information can be used for identifying accessions with the optimal FAC for their involvement in breeding oilseed hemp varieties.

Photosynthesis is one of the main biological processes that ensure life on the planet. The use of knowledge about the genetic control of chlorophyll biosynthesis will help to increase the productivity of flax. The paper presents a study of hybrids from the crosses of five lines defective in chlorophyll coloration and five with green coloration of the plant, differing in other morphological characteristics.

Inheritance of 4 nuclear genes controlling the chlorophyll coloration of the plant has been established. The independent genes ygp1 (in the gc-210 line) and ygp2 (in the gc-473 line) control the yellow-green coloration of a young plant (Xanthovirescens). The complementary interaction of these genes, which causes the yellow color of a young plant, has been demonstrated. The genes ygp2 (in gc-473) and ygp2-2 (in gc-570) were proved to be allelic but not identical, since mutations were obtained independently. The non-cumulative polymeric gene interaction which has been established in the case of zeb1 and zeb2 genes (both in the gc-281 line), cause an increase in photosensitivity and alternation of white and green stripes of leaves (Viridoalbostriata). These genes mask the action of the ygp1 and ygp2 genes. For the first time in the world, the maternal type of inheritance of the chlorophyll coloration of the plant, controlled by the chloroplast gene ygp3 of the gc-480 line, has been established in flax. It was found that the gc-570 line, in addition to the ygp2-2 gene, is homozygous for the genes CSB1 (ciliation of the false septa of the boll) and YSED1 (dominant yellow seeds), while the gc-480 line, in addition to the ygp3 gene, is homozygous for the CSB1 and dlb3 genes (light blue corolla). The allelism but not equality of the dlb3 genes in the gc-480 and gc-210 lines has been proven. The genes ygp1 and ygp2, which are responsible for chlorophyll coloration may be promising for labeling varieties. It is necessary to study them in more detail for the possible creation of plastic varieties capable to endure unfavorable environmental conditions at early stages of development.

Due to climate change and the industrialization of agriculture, the role of genetic collections is increasing. The paper characterizes 41 flax lines with mutations regarding chlorophyll coloration from the VIR genetic collection: 5 parental lines created on the basis of the VIR global flax collection, and 36 recombinant ones.

Among the 36 created recombinant lines, homozygous for two or more genes of morphological traits, there are those with chlorophyll deficiency and differences in anthocyanin color, stem shape and ciliation of the septa of the boll. Anthocyanin coloration and other morphological features were controlled by one or two of the 22 genes identified by us. Four of the recombinant lines were also homozygous for two or three independent chlorophyll coloration genes.

It was established that the genes of chlorophyll coloration and 22 genes controlling other morphological features act independently.

The ygp1 and ygp2 genes do not have a significant effect on most economically valuable traits, except for early flowering, and can be used for labeling varieties.

The genes s1, YSED1, ysed2 and rs1, which determine the yellow seed color, are necessary for the creation of flax varieties for food purposes, which makes the 11 lines based on these genes in demand for breeding purposes.

In flax, the molecular genetic function of none of the chlorophyll coloration genes is known, so the created genetic collection will be in demand to solve this problem.

Background: Abiotic environmental stress factors such as salt stress, drought, oxidative stress adversely affect the development and productivity of plants. To combat adverse environmental conditions, plants have developed a number of protective mechanisms. MAP kinases are protein kinases that regulate cellular activity in response to extracellular stimuli. Given the significant role of MAP kinase mechanisms in universal biological processes, elucidation of its role and mechanisms can be used to create stress-resistant genotypes. The use of stimulators and blockers of MAP kinase mechanisms is promising as a new direction in the management of plant stress resistance. The main goal of the conducted research is the comparative analysis of expression patterns of cotton accessions under salt stress conditions, the study of the relation between an increase in salt concentration and the change in the level of transcripts. Thirteen cultivars from Azerbaijan, nine from Turkey, four from Uzbekistan, four from Greece and one from Kyrgyzstan were used in the research, and changes in the expression level of the GhMAPK gene in cotton accessions was studied with the application of the real-time PCR analysis. In the present study, the evaluation of thirty-one cotton cultivars under different salt stress (NaCl) concentrations revealed significant differences in gene expression levels between cultivars of the same species. The ‘Navai-9’ cultivar from Uzbekistan had the highest expression level at both 100 mM and 200 mM salt concentrations compared to all other cultivars. Among local cultivars, cv. ‘Ganja-110’ (at 100 mM salt concentration), and cv. ‘Zafar’ (at 200 mM) differed from others in the level of changes in transcripts. In addition, there was a wide variation in the expression levels of stress-related genes between groups of accessions identified as resistant and sensitive, and within groups. Thus, both the increase and decrease in the expression level were found within these groups. This diversity in gene expression in sensitive and resistant cultivars in response to the salt stress shows that the mechanisms providing salt tolerance in the studied cultivars are different.

Abiotic stressors are the main factors limiting the expansion of territories occupied by grape plantations. Industrial viticulture is concentrated in the south of Russia and is limited by climatic factors that do not allow large-scale production in other regions of the country.

The present review considers the molecular mechanisms of resistance to low-temperature stress and discusses the role of the main genes determining the ability of plants to survive and acclimatize during a critical temperature drop.

One of the most studied ways of responding to cold stress is the interaction of genes in the ICE-CBF-COR cascade, however, a more accurate understanding of the genes responsible for resistance to abiotic environments specifically in grapes requires additional studies. A series of studies of functions of transcription factors and related genes of response to low-temperature stress in various species (Arabidopsis, tea, orange, blueberry, and grape) have identified four main regulons: 1) CBF/DREB, 2) NAC/ZF-HD, 3) AREB/ABF, and 4) MYC/MYB. Studies have demonstrated the function of the HOS1 gene, which negatively regulates the work of ICE1 (a key resistance factor). The review considers candidate genes in various species of annual plants: ICE1, HOS1, SIZ1, MPK3, MPK6, in families of genes: CBF, COR, RD 29A, LTI78, ERD, LEA; DREB1, ADREB1B; WRKY10, and in perennial crops: ICE1, CBF1, HSP70, SUS1, GST, DHN1, BMY5, BHLH102, GR-RBP3, ICE1, GOLS1, GOLS3; CBF; COR27, RD29B, NCED1, ERF105, ZAT10, SAP15, WRKY3, and LEA.

Until recently, interspecific hybridization was the leading method for obtaining cold-resistant grape varieties. The main donor of resistance is V. аmurensis Rupr. Recently, the research focused on the genetic basis of grape resistance to low temperatures is actively developing. For instance, a comparative analysis of the transcriptomes of two species contrasting in this trait, i.e. V. amurensis, resistant to low temperatures, and V. vinifera L. with low cold resistance, made it possible to identify three additional candidate genes with an increased expression in response to exposure to low temperatures, namely CBF3, ERF105 and ZAT10. At the same time, the practical application of modern accelerated breeding methods requires the identification of all additional key genes responsible for resistance to low-temperature stress. The components from the cascade of sequentially expressing ICE–CBF–COR genes (ICE1, ICE2, CBF1, CBF2, CBF3, and HOS1) have been selected as candidate genes.

The genus Paeonia L. includes both popular ornamental and medicinal plants with a rich history of cultivation and breeding. Breeding is an important process of increasing the diversity of the assortment and creating new cultivars of peonies with various economically important characteristics, such as the shape and color of flowers, different flowering periods and resistance to diseases and abiotic stressors. The main methods used in the breeding of peonies are traditional methods, including intraspecific, interspecific and intersectional hybridization, however, such factors as a long reproduction cycle and the complexity of the breeding process limit the possibilities for good progress in this work. The application of methods of biotechnology and molecular genetics make the breeding process more efficient. The use of germplasm resources and hybridization will accelerate the process of creating new cultivars not only with various decorative features, but also those with high adaptability to biotic and abiotic factors and resistance to phytopathogens and diseases. This review highlights the history of domestic and foreign breeding, modern trends and methodology of peony breeding. Information is provided on the achievements and limitations that exist in the field of molecular biological study of peonies.

Fruit crops are an irreplaceable source of essential nutrients, macro- and microelements, vitamins, organic acids, and antioxidants. Today, the overwhelming part of fruit supply in the market is provided by foreign producers. Import substitution and meeting the demand of the Russian Federation population for fruit consumption by the domestic agro-industrial complex is impossible without expanding the geography of cultivation areas, including those in zones of risky agriculture, which requires breeding of frost-resistant (cold-resistant) cultivars (fruit crops). Application of modern biotechnological and molecular genetic methods in breeding work will increase the profitability of fruit growing by reducing the time required for obtaining plants with the desired traits and by complex evaluation of the prospects of genotypes of parental forms. The present review considers modern data on cold tolerance genes of various fruit and berry crops, summarizes the known mechanisms of their action, activation, and regulation.

The review considers modern data on genes of fruit and berry crops resistance to low temperatures, including characterization of genes encoding key receptors, signaling, effector proteins, and transcription factors in apple, pear, peach, pineapple, and strawberry. The known mechanisms of their operation, activation, regulation are given, and signaling cascades are described.

Background. Climate change on the planet requires the creation of cultivars adapted to new conditions, which suggests a constant search for sources of the required traits, and the VIR cotton collection provides unlimited opportunities for breeding. Also, the harsh conditions of the northwestern Astrakhan region make it possible to identify the potential capabilities of the accessions. Materials and methods. 25 accessions of the VIR cotton collection were studied at the Caspian Agrarian Federal Scientific Center of the Russian Academy of Sciences (PAFSC RAS) in 2021 against the backdrop of adverse weather conditions. Comparative assessment of morphological and economically important features was carried out according to the VIR methodology. Factor analysis based on the principal component method has been performed. Excel 2016 and STATISTICA 7.0 were used. Results and discussion. The study resulted in the identification of accessions exceeding the ʻAC 5ʼ standard in terms of the yield. The Chinese accessions had a very good fiber yield and can serve as sources of this trait, although they are not too precocious and are characterized by a medium-size capsule. Unfavorable weather conditions during the period of fiber formation did not facilitate obtaining a very good quality fiber, but some accessions yielded fiber with a length of 32-33 mm. Conclusions. Factor analysis showed that American accessions are the least suitable for the conditions of the northern Astrakhan Region due to their late maturity and tall stature. The search for appropriate sources is promising among accessions originating from other regions.

In December 2023, the leading mycologist-phytopathologist of the Russian Federation, head of the laboratory of plant immunity to diseases of the All-Russian Research Institute of Plant Protection (VIZR), Doctor of Biological Sciences, Professor, Academician of the Russian Academy of Sciences Olga Silvestrovna Afanasenko celebrates her anniversary. The main direction of O.S. Afanasenko’s work is a comprehensive study of the mechanisms of variability in populations of phytopathogenic fungi, race-forming processes and interorganismal genetics in the pathosystems “cereal crops - hemibiotrophic pathogens”. In cooperation with colleagues from VIR, as well as from specialized institutions of the Russian Federation and foreign countries, research is being carried out to identify genes for resistance of grain crops to the most harmful pathogens.