Elizaveta Aleksandrovna Porohovinova

For the development of effective and secure methods for plant genetic resources preservation, different storage treatments of fiber flax seeds were compared. Seeds of the flax variety Orshanskiy-2 in aluminum foil bags were stored at different low temperatures, including in liquid nitrogen. Agronomic characters of plants grown from them and next-generation seeds were compared. Plants grown from frozen seeds changed 14 out of 31 evaluated characters in comparison with the non-frozen control. The biggest changes were detected after gradual freezing in liquid nitrogen, due to mechanical damage of the seed coat, and storage at −10 °C for 24 years. Freezing had a negative effect on production characters (straw, fiber and seed) because of the reduction of the germinated plant number. Seeds stored for 24 years at −10 °C, compared to control plants, ripened earlier, grew higher, produced a greater yield of straw and fiber, but had reduced fiber quality and increased seed size. Plants of the next generation showed a tendency toward attenuation of the storage time influence on flax characters. However, it is unknown how many years this process will take. For seed preservation in GeneBanks, it is recommended to use several variants of storage conditions and use rapid cooling and/or cryoprotectors. The latter two methods, which have been successfully used for other crops, should be implemented only after preliminary experiments.

Background. Rapeseed ( Brassica napus L. subsp. oleifera Metzg.) is a popular oilseed crop, widespread in the temperate climate zone. Its biological potential makes it possible to procure high seed yields under a wide range of weather conditions. Responses of new spring rapeseed cultivars and hybrids to temperatures and rainfall during the growing season are of interest. Materials and methods. The experiment was conducted in 2021–2023 in VIR’s experimental fields (Pushkin, St. Petersburg). The studied material included 6 cultivars developed in Russia, 3 cultivars from Sweden, and F ₁ hybrids from France, Germany and Austria. The duration of plant development periods, seed yield per area unit, and plant productivity were assessed, and indicators associated with the yield were measured. Results. The lowest seed yield was obtained in the unfavorable 2021. Statistically significant correlations linked only the following characters: duration of the flowering-to-harvesting and germination-to-harvesting periods; pod length and seed number per pod; seed number per pod and plant height. The highest seed yield was shown by cv. ‘Erebus’ released by Lipetsk Rapeseed Research Institute. In 2022, there were ten significant correlations. The group with the lowest seed yields included only cultivars, and the group with the highest ones incorporated only hybrids. The highest seed yield was recorded in 2023. The greatest contribution to seed yield was made by branched plants with a short stem, such as NXH2024 CL (Dow AgroSciences), and ‘Katinka’ (Sweden). The largest seeds in all years of observations were those of CL 6665383H (Pioneer), ‘Oredezh 6’ (Leningrad Research Institute of Agriculture), ‘Kalla’ (Sweden), and Caramino CL (Lembke KG). The earliest ripening was demonstrated by all hybrids from Lembke KG, and the cultivars ‘Oredezh 6’, ‘Larets’ (All-Russian Fodder Research Institute), and ‘Katinka’ (Sweden).

Background. Fiber flax breeding was for a long time targeted at increasing the fiber yield that entailed deterioration in its quality. A significant amount of fiber is required for the analyses of its quality characteristics, which slows down the breeding process. A reliable assessment technique is needed to select valuable genotypes by analyzing small amounts of material. Materials and methods. Fifty-three fiber samples representing the breaking load range (from 11 to 39 daN) were analyzed with two tools: the conventional method (standard) and the proposed (new) one. The technique we have developed is as close as possible to the standard one. The differences are in the replacement of the outdated DVK60 device with modern equipment, Instron 5943, which reduced the weight of a single sample 6.5 times. This substitution also affected the fiber selection procedure for assessing its fineness. Results. The new technique slightly overestimated the indicators: by 9% in breaking and rated relative breaking loads, 12% in flexibility, and 13% in fineness. Correlation analysis revealed high similarity between the results obtained with the standard and new methods (r = 0.88 for the breaking load, r = 0.83 for the rated relative breaking load, r = 0.67 for flexibility, and r = 0.68 for fineness). Analysis of variance showed a high significant effect of the genotype on the assessment results for the breaking load (92%), flexibility (75%), fineness (78%), and the rated relative breaking load (83%). Conclusion. The results obtained with the new technique are comparable with the evaluation data quantified according to standard procedure. It will provide reliable assessment of fiber quality in breeding material as early as in the 1st or 2nd year of seed reproduction from a single plant, which will reduce labor costs and accelerate selection of valuable genotypes.

Background. Peanut is a valuable crop for agriculture. Studies have shown that peanut is a naturally transgenic plant: its genome contains T-DNA, called cellular (cT-DNA), obtained during evolution from agrobacteria. The cus gene encodes cucumopine synthase, responsible for the synthesis of cucumopine. This gene was earlier proven to be intact in peanut and actively expressed in plant organs, but its effect is still unknown. We attempted to analyze important agronomic characters in a set of peanut accessions and find correlations between their manifestation and the cus gene expression level.Materials and methods. The study involved 63 peanut (Arachis hypogaea L.) accessions from the collection of the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). For 10 of them, the results of the analysis of the cus gene expression level in different organs were obtained. Ecogeographic tests were performed in 2019–2021 at two sites: the Kuban Experiment Station of VIR, and the Caspian Agrarian Federal Research Center. The indicators were described in accordance with the guidelines. The fatty acid composition in seeds was assessed using gas chromatography, while the protein content was measured using the Kjeldahl method. Statistica 7.0 software was employed for statistical data processing.Results and conclusion. Variability assessment of important agronomic characters studied during three years of ecogeographic tests, the Mann-Whitney U-test, and the factor analysis of principal components were applied to clarify the interplay of these characters with the expression level of the cus gene in different organs of peanut plants. The findings of this study disclosed some trends suggesting that a high level of the cus gene expression affected the productivity indicators in peanut.

The publication characterizes flavonoids – plant pigments, their role, classification, and biosynthesis. Attention is mainly paid to the enzymes of the cytochrome P450 class, which, in addition to their participation in flavonoid biosynthesis, play a major role in many other processes, such as polymer biosynthesis, hormone metabolism, and defense against unfavorable factors. Various information about the flavonoid 3 ’, 5 ’ -hydroxylase (F3 ’ 5 ’ H) gene is presented, highlighting key advances and major problems in its study. The role of this gene in anthocyanin biosynthesis is discussed, its product is shown to belong to the CYP75 enzyme family from the CYP71 clan of cytochromes P450, and the active centers of the enzyme are displayed. Flax usually has a blue corolla, and delphinidin as the main pigment in its coloration. In this publication, we characterized the d gene ( f3 ’ 5 ’ h ), which in recessive condition causes pink flower coloration and pelargonidin as the main pigment. It was shown that F3’5’H in flax belongs to CYP75 enzymes, but unlike most others is attributed to the CYP75B subfamily rather than CYP75A. The possibility of multiple allelism of F3 ’ 5 ’ H leading to different phenotypes was demonstrated, which confirms the multiple allelism of the d gene in flax, already known at the formal genetic level. At present, flax is the only species wherein the emergence of F3’5’H activity went to the detriment of F3’H, probably because flax is phylogenetically distant from other ancient cultivated plants and its evolution is associated with selection for yellow seed color.

Background. The XRQ sunflower genome has been sequenced but not yet fully annotated, and not all candidate genes for most traits have been identified. Disclosing the relationships among traits in this study will help to understand the genetic control over phenotypic characters.Materials and methods. A set of 237 sunflower lines from VIR’s genetic collection was phenotyped for their morphological characters (plant height; branching type; shapes and sizes of the leaf, petiole, flower head, disk and ray florets; downy mildew damage rate) and genotyped with molecular markers. DNA markers were used to identify accessions carrying the Rf gene and CMS. Factor analysis was applied to structure the genetic collection.Results and discussion. The data of 2017 and 2018 were compared using the analysis of variance. The results of the latter testified to the heritability of morphological characters, as well as to the alignment and purity of lines from VIR’s genetic collection of sunflower. New data were obtained on the phenotypic diversity of sunflower and stability of its agronomic traits across the growing seasons.Conclusion. Groups of interacting characters were identified by the factor analysis: 1) plant height, and duration of the growing season phases; 2) pollen fertility restoration with CMS PET1, SCAR markers HRG02 and HRG01 of the Rf1 gene, and branching; 3) the color of ray and disk florets, and petiole shape, as well as lamina surface shape. Lines with CMS PET1 were classified into three groups differing in the systems (possibly genes) of pollen fertility restoration. The factor analysis made it possible to confirm the assumption that several Rf genes whose manifestation differed from the Rf1 gene were present in the studied sunflower lines from VIR’s genetic collection.

Background. Phytophthora infestans (Mont.) de Bary is a well-known serious pathogen that affects a wide range of currently grown potato cultivars. Control of the disease, including the breeding process, is complicated by the fact that leaf resistance to P. infestans is often unrelated to tuber resistance, resulting in the need to identify individual plants with leaf and/or tuber resistance to be used in breeding programs. In view of this, research efforts to identify such sources are quite relevant. The objective was to assess the occurrence of plants with resistance in both organs among different wild species and analyze the relationship between leaf and tuber resistance within them.Material and methods. Assessment of leaf and tuber resistance in 97 accessions belonging to 36 species was carried out under artificial inoculation. Using the data obtained on each individual plant, the connection between leaf and tuber resistance was analyzed by means of the Wilcoxon matched-pairs test and Spearman’s rank-order correlations.Results. The species with more frequent occurrence of plants combining leaf and tuber resistance and the species with the predominance of leaf or tuber resistance were identified. The statistical analysis did not show complete (100%) correlations between leaf and tuber resistance in any of studied species. In some cases, a significant positive or negative correlation between these characters was found. The assessment results for the studied species/accessions can facilitate the search for leaf and/or tuber resistance sources capable of improving potato cultivars susceptible to late blight.

The purpose of the study is to study samples of oilseed flax from the VIR collection, to identify the most promising for the conditions of the Northern Trans-Urals. Methods. Field experiments, observations and records were carried out according to VIR methods. The fat content in the seeds of flax varieties was determined using an AMB-1006M NMR analyzer. Results. As a result of studying 31 samples of the oilseed flax collection, the most productive ones were identified: k-5831 VIR 1650 (265 g/m2), k-5579 Voronezhskiy 1308/138 (261 g/m2), k-8409 Kinel’skiy 2000 (248 g/m2), k-8799 Avgust (241 g/m2) from Russia; k-6056 Bakhmal’skiy 105 (243 g/m2) from Uzbekistan; k-8606 Omega (241 g/m2) from Canada; samples with a high mass of 1000 seeds: k-8218 Micael (8.84 g) from Canada; k-8799 Avgust (8.70 g); k-8158 Sokol (8.64); k-5831 VIR 1650 (8.61 g); k-5579 Voronezhskiy 1308/138 (8.42 g) from Russia; samples with a high oil content in seeds: k-8729 Ba Ya No. 12 (50.6 %) from China; k-8799 Avgust (49.2 %) from Russia; k-6056 Bakhmal’skiy 1056 (47.6 %) from Uzbekistan; k-8610 McBeth (46.8 %) from Canada; k-7964 Rucheek (46.7 %), k-5579 Voronezhskiy 1308/138 (46.7 %), k-8158 Sokol (46.6 %), k-6986 Sibirskiy-397 (46.6 %) from Russia. Promising for use in breeding programs when creating new varieties of oilseed flax in the region can be considered samples characterized by high and elevated indicators of such important economic characteristics as yield, weight of 1000 seeds and oil content in seeds: Voronezhskiy 1308/138, Avgust, VIR 1650, Sibirskiy-397 from Russia, Oliver from France.

Weather has significant impact on plant growth and development. It is important to analyze the influence of changing climate conditions on the expression of plant agronomic characters. Two flax varieties were grown from 1987 to 2018 in the Northwest of Russia. Weather conditions and their influence on flax agronomic characters were analyzed using the variance and correlations analyses. Significant influence of conditions of a particular year on the manifestation of all evaluated characters was revealed. Starting from June, high temperatures accelerate plant development at all stages. Prolongation of the germination-flowering period is most important for improving fiber productivity, while fast ripening in hot weather after flowering is preferable for the formation of high-quality fiber. Such data give a possibility to predict the yield amount and quality. The use of weather conditions data also makes possible a comparison of the results obtained in different years. The suggested method of classifying meteorological conditions of a year can be used in other genebanks for systematizing and analyzing the results of crop evaluation in the field. The correlation analysis revealed 3 correlated pleiades, namely (1) of productivity, (2) of fiber quality and yield, and (3) of the growing season phase durations, the sums of active temperatures and precipitation during each period. The great influence of growing conditions on the economically valuable traits indicates the necessity of searching for genotypes with stable character manifestations for breeding new varieties with stable yields and good fiber quality.

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.