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Background. A calibration model has been developed for rapid assessment of economic value indicators (protein, oil, and quinolizidine alkaloid contents) in the seeds of narrowleaf lupine accessions from VIR using near-infrared spectroscopy, with the help of which it is possible to decide on the further use of the accessions.Materials and methods. Biochemical quality indicators (protein, oil, and quinolizidine alkaloid content) were studied in the seeds of narrowleaf lupine (Lupinus angustifolius L.) grown in 2019 in the northwest of Russia. Calibration models for measuring protein, oil and alkaloids in lupine seeds (62 accessions) were developed using a MATRIX-I IR analyzer (Bruker Optics, Germany). To construct calibration models, we used the values obtained by chemical analysis methods accepted at VIR. The oil content in lupine seeds was assessed by the defatted dry residue technique in Soxhlet extractors, protein by the Kjeldahl method, and quinolizidine alkaloids by gas chromatography coupled with mass spectrometry. All indicators were recalculated on the dry-weight basis.Results and conclusion. Statistical significance of the developed models was verified according to the results of measuring the content of protein, oil and alkaloids in the seeds of the test batch. The protein and oil content data obtained using a calibration curve did not differ significantly from the results of chemical studies, in contrast to alkaloid indicators. Consequently, the developed calibration model for the MATRIX-I IR analyzer can be used for rapid assessment of protein and oil content in narrowleaf lupine flour samples, thus accelerating the process of obtaining data on the main economic value indicators. The analysis does not require reagents and is safe.

On January 16, 2023 we celebrated the 75th birthday of Professor Alexey V. Konarev, Doctor of Biological Sciences, a renowned scientist in the sphere of plant biochemistry and molecular biology, one of the eldest staff members of VIR.

Background. The use of faba bean (Vicia faba L.) as a feed and food plant is hindered by the presence of antinutritional substances and in particular phenolic compounds – tannins – in the seed coat. The existence of low-tannin or zero-tannin forms in the faba bean gene pool allows breeders to promote this trait. The aim of this work was to carry out biochemical validation of a known morphological marker of low tannin content and identify relationships of some phenotypic traits characterized by accumulation of phenolic compounds (tannins and anthocyanins) with their concentration for use as additional morphological markers of the low content of these antinutrients in bean seeds.Materials and methods. Associations of the presence/absence of anthocyanin in seedlings, pigmentation on petals, and dark extrafloral nectaries on stipules with the content of tannins and anthocyanins were analyzed in 10 faba bean accessions with different seed coat colors from the VIR collection. The plants were grown and evaluated in Leningrad Province in 2020–2021. Tannins in seeds were assessed using Leventhal’s method. Anthocyanins were analyzed in the green biomass of plants using a spectrophotometric method.Results and conclusion. Different combinations of the studied morphological features associated with the coloration of the studied organs were found. A high positive correlation between the levels of anthocyanins and tannins (r = 0.79) was identified as well as a direct connection of the high value of these traits with the presence of a dark extrafloral nectary on stipules and anthocyanin in seedlings. The absence of anthocyanin staining on seedlings and the absence of dark-colored extrafloral nectaries on stipules can serve as markers of low-tannin genotypes in the early stages of plant development. The light seed coat color that does not darken for a long time may also be the evidence of low tannin content.

Background. Oat (Avena sativa L.) is one of the most important sources of protein, oil, starch and dietary fibers, in particular β-glucans. Dietary fiber serves as a source of nutrition for the intestinal microflora and significantly affects not only its composition, but also the normal functioning of the intestine as a whole. In connection with the increased interest in β-glucans as a food component and dietary supplement, there is a need in a convenient and inexpensive method for determination of β-glucans content in grain. The article provides an overview of the existing methods for the isolation and determination of soluble β-glucans in cereals: enzymatic, alkaline, alkaline-enzymatic, colorimetric; their advantages and disadvantages are noted. The main disadvantages of some methods are the complexity and duration of execution, significant cost of the required reagents, and the inability to determine the exact content of β-glucans due to their insufficient purification from various impurities.Results. This study used the example of naked and covered oat cultivars to demonstrate applicability of the gravimetric method that we developed by modifying the alkaline method. Whole grain oat flour was pretreated with a 50% ethanol solution to inactivate β-glucanase and remove free sugars, some lipids, proteins, and other substances. β-glucans were released from the aleurone layer and the endosperm with a 5% sodium hydroxide solution, and finally extracted with a 70% ethanol solution. Β-glucans floated to the surface in the form of a bunch of fibers, which was then dried at a temperature about 100-102°C to constant weight and weighed. The content of β-glucans was calculated from the dry weight (%). The isolated β-glucans were checked for the presence of accompanying substances: the content of nitrogenous substances was determined by the Kjeldahl method, and the presence of starch was determined by a qualitative reaction with Lugolʼs reagent.Conclusions. The content of β-glucans in the grain of the studied samples ranged from 3.12±0.18 up to 4.65±0.17% of the dry weight. As a result of the study, the optimal conditions of β-glucans isolation were selected: the extraction mixtures ratios, as well as the modes of centrifugation, sedimentation and drying were established. It has been shown that this method makes it possible to isolate β-glucans with a minimum impurity of nitrogenous substances (0.07-0.12%) and no traces of starch. One of the advantages of the described method is its availability for mass analysis when studying a collection of grain crops.

Narrow-leaved lupine (Lupinus аngustifolius L.) is a widely cultivated leguminous forage and green manure crop with a potential for human nutrition. However, the presence of secondary metabolites – alkaloids – in lupine seeds considerably affects the quality of raw produce, reducing its nutritive value; in addition, high concentrations of alkaloids are toxic to humans and animals. Therefore, plant breeders working with lupine need to gain knowledge about the variability of alkaloid content in seeds of different genotypes and search for the sources of their low concentrations in the crop’s gene pool. The collection of narrow-leaved lupine genetic resources held by the N.I. Vavilov Institute of Plant Genetic Resources (VIR) offers wide opportunities for such search by means of mass screening. For its part, largescale gene pool screening requires the selection of an optimal technique to measure alkaloid content in seeds, so that it would be easily reproducible and as little labor-, time- and fund-consuming as possible. The results of the search for such method are presented. Qualitative and quantitative indices were compared when target compounds had been extracted with multicomponent mixtures and individual reagents (chloroform, methanol, etc.) and the extracts analyzed using gas chromatography-mass spectrometry. High-performance liquid chromatography combined with mass spectrometry was also employed. Five major alkaloids were found to be present in all types of extracts: lupanine, 13-hydroxylupanine (dominant ones), angustifoline, sparteine, and isolupanine. The fullest extraction of alkaloids was observed when the extractant with an added alkaline agent was used (425 mg/100 g). The lowest level of extraction was registered with chloroform (216 mg/100 g). The significance of the differences was confirmed statistically.

Background. An important trend in modern breeding of common beans is to improve the quality of grain. High protein content in seeds is one of the most important indicators of the nutritional value of beans. Searching for high-protein accessions, identifying sources of high protein content, and using them in the breeding process, while developing new cultivars, still remain relevant. The aims of our research included the identification of variability patterns for protein content in accessions of different origin, characterization of cultivars, and description of their morphological and economic traits.Materials and methods. Presented here are the results of biochemical screening of 166 common bean (Phaseolus vulgaris L.) accessions of various ecogeographic origin, added to the VIR collection in 2005–2016. Field study of economically valuable traits was carried out according to VIR’s techniques. The protein content in seeds was measured in the Biochemistry and Molecular Biology Department at VIR using Kjeldahl method. Mathematical data processing (correlation analysis and single-factor analysis of variance) was performed using Statistica 7.0 software (StatSoft, Inc., USA).Results and conclusions. As a result of the assessment, 12 sources of high protein content in seeds (> 28% annually) were identified and described. The average value of the trait differed depending on the country of origin, genotype and year of study. The correlation analysis failed to find general regularities (strong stable interrelations) between the protein content in seeds and morphological, economically valuable traits. The values of correlation coefficients were unstable over the years of study. Weak links between the protein content and the genotype (r = 0.25) or the year of reproduction (r = 0.24) were identified. Significant relationships between protein content, morphological and economically valuable traits were not found. Seed protein content, according to the results of the single-factor analysis of variance, largely depended on the genetic properties of plants (effect size is 70.1%), and, to a smaller extent, on the year of reproduction (14.5%) and origin (17.5%).

Background. We tested soybean accessions from the VIR collection. These accessions had not been tested earlier at any experiment station of VIR.Materials and methods. The testing was carried out at the Black Sea Coast of the Caucasus. We tested 494 soybean accessions of various geographic origins. These accessions arrived to the VIR collection from 1922 to 1995. Our work was done according to VIR's methodological guidelines.Results. Almost half of the accessions of various maturity groups manifested high seed productivity (> 30g per plant). There were no accessions with high seed productivity among the earliest maturity group (growing season of 81-90 days). Productivity was positively correlated with the duration of the growing season (r = 0.39). The weight of 1000 seeds varied from 60g to 500g and had no apparent connection with productivity. Elevated position of the lower bean is important for mechanized harvesting. Only in 27 accessions the lower bean was set higher than 12.1 cm. Among them, 23 accessions were very late-ripening, and only 2 matured within the season of up to 130 days. Accessions with high crude protein content in seeds (45.1-50.0%) were found in all maturity groups. Maximum oil content (24.1-26.0%) was registered only in the accessions whose growing season was from 91do 150 days. Accessions with the shortest (81-90 days) and longest (> 150 days) growing seasons did not contain much oil. High productivity was combined with high protein content in the early-ripening accession k-2341 from China (growing season of 101-110 days), late-ripening variety 'Morse' from the U.S. (141-50 days), 'Shhepis 2' from Georgia, 'Axagara' and 'Tou kichi 1' from Japan (>150 days). High productivity and high oil content were observed in the U.S. varieties 'Sherman' (121-130 days) and 'Ripley' (141- 150 days). The correlation between protein content and oil content was negative (r = -0.55). Full-scale characterization of the studied material has been published in The Catalogue of the global VIR collection, issue 855, 2018.Conclusion. The conducted research helped to describe earlier untested materials in terms of their productivity and biological characteristics. Accessions with the best economic characteristics can be used in breeding practice to develop new soybean cultivars.

For a targeted search of initial breeding material for the quality of soybean seeds, it is necessary to know the patterns of the dependence of the corresponding seed characters on the weather and climatic conditions in a particular region. Global climatic change, the concretization of which is relevant, has a share in this dependence. Thus, the aim of this work was to identify the relationship between the variability of protein and oil content in soybean seeds with climatic parameters in the North Caucasus as well as trends in this variability over a long time period. The study of 1 442 soybean accessions from VIR collection in the Krasnodar region during 1987–2015 had been carried out and the tendencies of the variability of protein and oil content in seeds in this environment were estimated. The regression analysis in differences with forward stepwise selection of variables has been used to construct models for the dependence of the protein and oil content on generalized agrometeorological indices. During 1987–2015, for the period with temperatures above 10 °C, the sums of active temperatures increased by 218 °C/10 years and precipitation decreased by 20.9 mm/10 years. In the dynamics of protein content, a trend has been revealed as an increase by 2.5 % over 10 years, while there is no reliable trend in oil content. The maximum average mean of oil content and the smallest protein were in the middle-maturing accessions (22.2 and 38.8 %), and a relatively high protein content was detected, on average, in the early- (21.6 and 40.0 %) and late-maturing (20.2 and 39.9 %) varieties. The protein content had been increasing with a growth of the duration of the period with temperatures above 22 °C and decreasing with a raise in precipitation over a period of temperatures above 18 °C. The accumulation of oil in seeds was promoted by an increase of the hydrothermal coefficient over the period with temperatures above 19 °C, and, in late-maturating varieties, prevented by a prolonged autumn period with temperatures below 15 °C. Long-term growth in protein content is due to both climatic change and genetic improvement of varieties.

Methods for identification of duplicate accessions in genebanks and the term “duplicate accession” are discussed. The results of comparative field and laboratory analysis of 112 pairs of potential duplicate accessions from the oat collections of VIR and NordGen are presented. The revealed conformity between the results of the field and laboratory tests proves the use of avenin electrophoretic banding patterns for duplicate identification in the oat collections before field testing or in case of loss of germination in the seeds of the tested accessions.