Background. Genotype–environment interaction complicates selection of lines in plant breeding. Researchers have developed different ways to classify environments to mitigate its effect. The use of correlation analysis between yields of cultivars grown in different environments was earlier proposed for classification of these environments.

The aim of this research was to classify years on the basis of correlations of the yields in a specially selected set of spring bread wheat cultivars and to verify the application of such classification to breeding material in different nurseries.

Materials and methods. The material for the experiment included cultivars, lines and breeding samples from the collection nursery, competitive variety trials, and the nursery for segregating populations, respectively. The experiments were conducted from 2010 through 2017. The correlation analysis between the yields of 19 marker cultivars of different ecogeographic origin was used as the basis for the classification of years. The calculated correlation parameters for the yields of marker cultivars and those of the breeding material in nurseries for the same pairs of years were compared using the Mann–Whitney U-test.

Results. The years under consideration were classified into three groups: 1) 2010 and 2013; 2) 2011, 2012 and 2014; 3) 2015, 2016 and 2017. Correlations between the yields of the marker cultivars showed no significant differences from those of the genotypes from other nurseries across the analyzed years. Consequently, the classification of years based on the reactions of marker cultivars can be justifiably extended onto other breeding material.

Conclusion. It is suggested to select and use a set of marker cultivars in multi-environment trials to obtain additional information about target environments and make more informed decisions on culling plant breeding materials. 

Background. Studies into the adaptability of the genetic diversity of cultivated plants and their wild relatives to various environments are induced by global climate change. Introduction of adaptive wheat cultivars resistant to environmental stressors is the basis for stable harvests. This article presents the results of a research into the adaptive value of indigenous durum wheat varieties and improved cultivars released in different years in Azerbaijan.

Materials and methods. The experiments were carried out in the foothills of Mountainous Shirvan under unsecured non-irrigation at Gobustan Experiment Station of the Research Institute of Crop Husbandry. In 2012–2014, contrasting in weather conditions, levels and structure of yield were analyzed. VIR’s guidelines were used to study 42 durum wheat varie ties, including 10 landraces. The years of study differed sharply in rainfall. Selyaninov’s hydrothermal coefficient was used to assess the conditions of growing seasons.

Results. Mostly modern cultivars of the semi-intensive type were distinguished for a set of agrobiological traits. Adaptability coefficients (0.81–1.23) showed that the response of the studied varieties to unfavorable conditions was highly expressed. Indigenous landraces ‘Ag bughda’ and ‘Bozak’, old breeding varieties ‘Arandani’, ‘Ag bughda 13’, ‘Kahraba’ and ‘Mirbashir 50’, and new cultivars ‘Karagilchig 2’ and ‘Barakatli 95’ had the highest adaptability coefficients. The first of them demonstrated stable yield, and the latter two were also resistant to stressors.

Conclusion. Durum wheat yields under the conditions of moderately continental climate in Mountainous Shirvan depended on the number and weight of grains per ear. The varieties identified for the best adaptability are recommended to be included in crosses to develop new plastic cultivars of durum wheat. 

An important area of crop development is the introduction of new vegetable plants, one of which is the sweet potato Ipomoea batatas (L.) Lam. The aim of our research was genetic, biological and economic assessment of sweet potato accessions held in the collection of the Plant Introduction and Acclimatization Dept., Udmurt Federal Research Center, Ural Branch of the RAS (UdmFRC UB RAS).

Within this experiment, DNA polymorphism of 16 accessions of I. batatas was tested using ISSR markers. All accessions were found to represent different genotypes; the VM 17 accession obtained as a result of a bud mutation differed significantly from the original accession in its genotype.

Evaluation of 16 accessions of sweet potato cultivars was carried out in a small-plot field experiment. The results of biological and economic assessment witnessed to the prospects of sweet potato cultivation within the territory of the Udmurt Republic for marketable tuber production. The productivity of the accessions was 140–2700 g of tubers per plant. According to their productivity, the accessions were divided into clusters: the low-productivity group (up to 500 g), with ‘Betty’, Fioletovy, ‘Beauregard’, ‘Covington’ and Bezhevy; medium-productivity group (500–1000 g), with ‘Jewel’, Fioletovy Sochi, Brazilsky, Afgansky, Vinnitsky rozovy, Lyubitelsky and ‘Bayou Bell’; and high-productivity group (more than 1000 g), with Pobeda 100, ВM 17, Druzhkovsky and Bely NBS. On the basis of the evaluation, 11 sweet potato accessions were recommended for cultivation in the Middle Urals: Afgansky, ‘Bayou Bell’, Bely NBS, ВM 17, Brazilsky, Druzhkovsky, Fioletovy Sochi, ‘Jewel’, Lyubitelsky, Pobeda 100, and Vinnitsky rozovy. 

Background. Representatives of the genus Allium L. are valuable food and medicinal plants that have long been used for nutrition and human health. Modern research has proved their high biological activity. Earlier, we investigated the aboveground organs of a number of wild onion species in the consumer ripeness phase. Higher content of secondary metabolites has been observed in the hemiephemeroid species A. aflatunense B. Fedtsch., A. microdictyon Prokh., and A. rosenbachianum Regel. The aim of this work was to determine the content of bioactive compounds in the green biomass of Allium species during flowering.

Materials and methods. We studied the freshly harvested raw materials – leaves and flower scapes. Dry matter content was measured by drying 1 g of raw material at 100–105°C to constant weight. The amounts of phenolic compounds, pectic substances, total sugars and carotenoids were assessed spectrophotometrically using the SF-56 (Russia) and SF Agilent 8453 (USA) instruments, and ascorbic acid was measured by the titrimetric method. The result was taken as an average of three measurements for each indicator calculated on absolute dry weight of raw material (except ascorbic acid).

Results and conclusions. The green biomass of Allium species was found to contain 8,2–16,2% of dry matter; 4,5–12,0% of phenolics (catechins, flavonols and tannins); 6,9–32,4% of total sugars; 9,5–12,6% of pectic compounds (pectins and protopectins); 20,8–102,5 mg% of carotenoids, and 38,0–197,7 mg% of ascorbic acid (wet weight). A significant range of variation in the content of secondary metabolites was due to the species’ characteristics and weather conditions of the growing season. A. microdictyon had a higher content of dry matter, flavonols and tannins, whereas A. aflatunense and A. rosenbachianum were rich in ascorbic acid and sugars. The findings testify to the prospects of using Allium spp. as a source of bioactive compounds. 

Background. The barley collection at the N.I. Vavilov AllRussian Institute of Plant Genetic Resources (VIR), being the main source of source material for breeding, is insufficiently studied under conditions of extreme continental climate. The purpose of the research was to assess the adaptability of barley cultivars held by VIR to extreme continentality.

Material and methods. The research targets were 24 barley cultivars representing various breeding centers and tolerance regions of Russia. The cultivar ‘Omsky 91’ developed at Omsk Agrarian Scientific Center was used as the reference.

Results and discussion. According to the genetic profiles for alleles of hordein-coding loci, provided by the Vavilov Institute of General Genetics, more than 70% of the studied barley cultivars (‘Chelyabinsky 99’, ‘Priazovsky 9’, ‘Zadel’, ‘Sokol’, ‘Zernogradsky 584’, ‘Zadonsky 8’, ‘Khadzhibey’, ‘Beatrice’, ‘Knyazhich’, ‘Zevs’, ‘Kazak’) were linear in their hordein-coding loci. The homeostasis of the cultivars, their stability indices and plasticity levels were calculated. Their intensity measures and selection differentials were determined.

Conclusion. The adaptability assessment based on the sum of ranks (calculated using the abovementioned adaptability parameters) showed that the monomorphic cultivars ‘Priazovsky 9’ and ‘Chelyabinsky 99’ as well as cv. ‘Severyanin’ (not listed in the State Register for Selection Achievements) were most adapted to extreme continental climate conditions (sums of ranks ranged from 8 to 29). The adaptability of the identified cultivars was confirmed by high-yielding hybrid populations produced from crossing the selected adaptable cv. ‘Chelyabinsky 99’ with cvs. ‘Omsky 91’ and ‘Omsky 95’ released by Omsk Agrarian Scientific Center. The obtained lines demonstrated higher yields than both the mean yield of the parent cultivars (+1.20 t/ha) and the yield of the best parent cultivar (+0.76 t/ha). 

Background. Innovative technologies for deep processing of grain are widely used in maize grain processing with the release of the grain germ for subsequent extraction of oil and starch from it or production of sugar substitutes in the form of fructose syrup and alcohol, bakery or feed protein. A search for economically valuable sources of maize starch, useful byproducts of its processing, and natural modification of starch for deep processing is vital.

Materials and methods. Ten high-starch maize accessions from the VIR collection, isolated by IR spectrometry, were studied. Starch content was measured according to GOST 10845-98, GOST 13586.5-93, GOST 10847-74 and GOST ISO 6647-1-2015 standards. Processing of grain into starch and assessment of the content of amylose and byproducts were carried out at the All-Russian Scientific Research Institute for Starch Products in 2018 according to L. P. Nosovskaya et al. The actual content of starch and its byproducts during deep grain processing was determined. The values of the actual percentage of dry matter (DM, %) in grain, mass fraction of starch, ash content, as well as the yield of extract, pulp, embryo, gluten, process water and starch were determined.

Results. Accessions with a high yield of starch (k-4520, k-9301 and k-24730), germ (k-4520. k-8785 and k-24731), pulp (k-4520, k-8785, k-9991 and k-24732) and protein (k8785) were identified as well as those with a percentage of amylopectin in starch above 82% (k-24730 and k-24733) and 100% (k-5461 and k-9991), and amylose above 30% (k4520 and k-9301).

Conclusion. Of practical interest in terms of the actual yield of starch (% DM in grain) are accessions k-4520, k-9301, k-24730, k-9991, k-5461 and k-4520. According to the results of breeding tests, accessions k-24730, k-24732 and k-24733 had the following values of starch harvest calculated for grain yield: 4.66, 4.41 and 4.18 t/ha, respectively. 

The Volga-Akhtuba Floodplain is among the areas with insufficient rainfall, where high air temperatures in summer are coupled with low humidity. An urgent task is to select carrot cultivars adapted to irrigated cultivation conditions. For this purpose, 101 carrot accessions of diverse origin were studied at Volgograd Experiment Station. The study was accomplished according to the guidelines developed by VIR.

The tested carrot accessions demonstrated different responses to abrupt changes in the temperature and water regimes. At the same time, differences were found in the yield and quality of roots. An important indicator was the stability of root yield. High-yielding cultivars with relatively stable yields were identified: ‘Nesravnennaya’ (k-1528, Russia), ‘Leninakanskaya’ (k-1936, Armenia), ‘Asmer Early market’ (k-2304, UK), and ‘Konservnaya-63’ (k-2320, Moldova). High yields and good marketability were shown by cvs. ‘Nantes’ (k-1438, Bulgaria), ‘Leninakanskaya’ (k-1936, Armenia), ‘Danvers’ (k-2167, USA), ‘Konservnaya-63’ (к2320, Moldova), ‘All Season’ (k-2598, Australia), and ‘Rogneda’ (k-2611, Russia). These cultivars originated mostly from arid areas. The content of chemical compounds in roots was highly variable, depending on the cultivar (hybrid) and, in particular, on the growing conditions. For example, the sugar content ranged from 3.0 to 6.85%, ascorbic acid from 7.9 to 12.2 mg/100 g, and carotene from 9.5 to 17.9 mg/100 g. The tests revealed a considerable variability in main agronomic characters of the carrot accessions, especially when high-yielding cultivars were concerned: they were the most sensitive to cultivation in arid environments and suffered a decrease in marketability. As a result of the study, carrot accessions combining high yield, good marketability and beneficial chemical composition were identified. They are promising for breeding programs aimed at the development of cultivars adaptable to high summer temperatures and low humidity. 

Background. Bread wheat (Triticum aestivum L.), due to significant progress in breeding, has high potential of biological productivity, but its implementation is quite low. To change the situation for the better, it is necessary to increase the resistance of developed cultivars to unfavorable abiotic and biotic factors in the regions of its cultivation. To solve this problem, source material is required. The purpose of this research was to evaluate a set of winter wheat accessions from the VIR collection, and first of all, the newly introduced accessions, and the accessions from the working collection of Kazan Scientific Center of the Russian Academy of Sciences for variability of agronomic traits and stability under the conditions of the north of the Middle Volga region, and to identify sources promising for inclusion in the crossing programs.

Materials and methods. A three-year field study of 166 winter bread wheat accessions was carried out. All accessions were assessed for their overwintering and plant and ear productivity traits using the methods developed by VIR and the State Variety Trials. The best accessions, or sources, were selected by comparing them with the reference cv. ‘Kazan 560’, taking into account the quantitative values of such indicators as “general adaptability” (ОАС_i ), variance of “specific adaptability” (σ2_САСi ) and “relative stability” (S_gi) for each accession according to A. V. Kilchevsky and L. V. Khotyleva.

Results and conclusion. Descriptions of winter bread wheat accessions are presented in the context of their agronomic traits. Groups and subgroups of accessions with different trait variability levels were identified. Some accessions with stable levels of trait manifestation exceeded the reference in ear productivity. All of them are promising for wheat breeding programs. It is shown that the group of accessions “weakly changing” over the years of study differs from the group of “moderately/strongly changing” accessions in values of correlations between traits and the number of significant correlations. 

Background. The length of the growing season is a limiting factor in many regions with unstable climatic conditions. The development of ultra-early barley donors makes it possible to accelerate the breeding process aimed at producing commercial cultivars adapted to cultivation area requirements.

Materials and methods. The donors Kibel, Kibel uluchshenny, Kibtsel and Kibkor were obtained through individual selection of barley forms combining earliness and productivity from the hybrid combination Belogorsky × k-15881. The experiments were carried out according to the approved guidelines. Yield components were used to calculate the index of productivity for the donors versus the reference cv. ‘Belogorsky’.

Results and conclusions. Earliness is controlled in the donors by three recessive genes. The donors’ period from emergence to heading was 7–9 days shorter than that of the reference cv. ‘Belogorsky’, with a low norm of reaction, which attested to their high adaptability. The resulting barley forms were highly resistant to lodging. The donor Kibel uluchshenny in all spike yield components did not differ from the reference. The other donors were close to the reference in spike length and 1000 seed weight. The example of Kibel uluchshenny was used to demonstrate the possibility of producing barley forms combining high earliness and good productivity. The developed donors may prove useful in the breeding for earliness in the areas where the length of the growing season is a limiting factor. 

Background. While working with such cross-pollinated crops as sugar beet, the greatest problem is the fixation of valuable genotypes. Using apomixis to produce breeding material helps to accelerate the breeding process and save the desired combination of genes.

Materials and methods. The research objects were 110 accessions of sugar beet from the VIR collection. Field experiments and assessments of the resistance to Cercospora leaf spot, monogermity, and non-bolting were performed according to VIR’s guidelines in 2016–2018 at Pushkin and Pavlovsk Laboratories of VIR and Maikop Experiment Station of VIR. The sugar level in roots was measured using an optical refractometer.

Results. A comprehensive study of sugar beet accessions resulted in the development of apomictic lines with cytoplasmic male sterility, followed by an evaluation of their economically important characters. An extremely rare occurrence of biotypes with the 0-type sterility (less than 0.5%) was observed in the population. The seeds obtained from apomixis-prone lines demonstrated a significant difference during inbreeding from the seeds of fertile inbred genotypes: no inbreeding depression was observed in apomictic lines. Lines combining sterility and monogermity in their genotype were produced. Testing parent accessions and apomictic forms did not reveal significant differences in the sugar content and root yield, so the resulting forms can be efficiently used in future breeding programs.

Conclusion. Using apomixis to develop sugar beet lines helped to fixate the sugar content level, biennial plant development cycle, and Cercospora leaf spot resistance. Thus, apomixis is promising for ensuring maternal inheritance and preserving the desired combination of genes in sugar beet, thereby accelerating the breeding process. 

A priority of agricultural production for the Northwest of Russia is to develop and introduce winter-hardy and productive cultivars of small grain forage crops, such as winter triticale, capable of producing high yields of grain and green biomass.

‘Bilinda’, a new promising tetraploid winter triticale cultivar grown for grain forage, was studied from 2004 through 2019 at Leningrad Research Institute for Agriculture “Belogorka”. The data of the State Variety Trials (2017–2019) were also taken into account. Conventional techniques were used in the experiments, phenological observations, field and laboratory evaluation tests, and statistical data processing. Electrophoresis of gliadin in the grain of cv. ‘Bilinda’ and its registration as a “protein formula” were performed using the technique developed and approbated by the Molecular Biology Dept. of VIR. The hexaploid winter triticale cultivar ‘Kornet’ (k-3636) served as the reference. Cv. ‘Bilinda’ was developed using individual and mass selection of genotypes with recessive control of the ear’s morphological characters, which resulted in producing a homogeneous population with high yield potential and large plump grains. On average across the testing period, cv. ‘Bilinda’ significantly exceeded the reference ‘Kornet’ in grain yield (+1.04 t/ha), number of grains per ear (+32.3 pcs), and 1000 grain weight (+7.7 g), and in addition demonstrated higher winter hardiness than the reference (up to 98%). Under epiphytotic incidence of Septoria leaf blotch, the tested cultivar manifested a high level of resistance (scoring 7–9 points). ‘Bilinda’ is among high-yielding cultivars resistant to most leaf diseases. In 2020, this cultivar was approved for cultivation in the Northwestern Region (2) of Russia. Applying the method of variety identification based on the electrophoretic spectra of gliadin, a storage protein in grain, a protein “passport” was produced to ensure monitoring of the cultivar’s integrity and authenticity. 

Modern breeding, especially when fruit plants cultivated for decades at the same location are concerned, requires a new strategy to develop cultivars resistant to abiotic limfactors of the environment. A more in-depth analysis of genotype–environment interaction phenomena is needed, as modern studies have shown that the level of plant productivity and yields is determined not by specific “genes of quantitative traits”, but mainly by the emergent (newly occurring when a lim-factor of the environment changes at the ontogenetic and phytocenotic levels) effects of the genotype–environment interaction (GEI). New knowledge is needed about the values of contributions to the productivity of a cultivar made by each of the genetic–physiological systems of plant adaptability (GPS-ad) when exposed to a particular lim-factor of the environment at a particular phase of ontogenesis. For the first time, aiming at finding promising peach genotypes for further breeding, we studied their adaptability to low temperatures in different horticulture zones of Krasnodar Territory.

Shifts in the effects of low-temperature environmental stressors in the developmental phases of cultivars (produced by climate change) were analyzed in the time interval of 1985–2018.

The presence of hereditary adaptive reserves for increasing peach productivity for each phase of development in the process of studying the phenomena of GEI was disclosed. Recommendations are given to breeders on phase-to-phase breeding of future cultivars: how to protect their production process at each developmental phase from negative effects of low temperatures. 

Background. As reported by the Russian Federal State Statistics Service, spring bread wheat planting acreage in 2019 reached 48% (28 million ha) of the total crop area in Russia. About 20% (5.4 million ha) of spring wheat was cultivated in the Siberian region. This is the reason why the region plays an important role in wheat cultivation, and the development of highly efficient cultivars adapted to Siberian environments is one of the prioritized tasks in the efforts to obtain sustainable spring bread wheat harvests.

Materials and methods. Mutants and mutant × cultivar hybrids were used as parent material for top crossing. A decision was taken to apply multifold individual selection in accordance with the composition of agronomic traits in the mutant × cultivar hybrid population Lutescens 3 × [F₅ B1 (Mutant 777 × G7251/03) × G7251/03] × Rosinka 3 (Mutant 112 × Irtyshanka 10) with backcrossing. In 2001–2016, expe rimental work was conducted at Omsk Agrarian Scientific Centre. Environmental testing was carried out at the Stepnoy Experiment Station (the steppe zone of Omsk Province) and the A.I. Barayev Research and Production Centre for Grain Farming (Northern Kazakhstan). The experiments and observations were performed in accordance with the techniques recommended by the State Commission for Crop Variety Trials.

Results. The research showed that cv. ‘Omskaya Yubileynaya’ was characterized by resistance to lodging and to major plant diseases. It exceeded the reference in grain yield both in fallow (+0,50 t/ha) and nonfallow lands (+0,58 t/ha). The distinguishing feature of this cultivar was its large grain of high quality.

Conclusions. During the development of cv. ‘Omskaya Yubileynaya’, the data were obtained that justified its prospective cultivation within the steppe and forest-steppe zones of Siberia and Kazakhstan. The cultivar has been registered in the national lists of breeding achievements since 2019. 

Background. The collection of durum wheat landraces (Triticum durum Desf.) at VIR contains unique material of the “Russian northern branch”, which is not found in any other collections worldwide. Studying the genetic diversity of such wheat accessions according to their gliadin bands as markers of genotypes is important for identification and conservation of their gene pool authenticity.

Materials and methods. For the first time, molecular markers were used to differentiate among 38 accessions of the local durum wheat variety known under the name of “Kubanka”, collected and placed into the VIR collection in the 1910–1940s, and five accessions from the seed genebanks of the USA and Canada. Electrophoretic patterns of gliadin were used as markers of genotypes within the polymorphic cultivar. Recording bands in the form of “protein formulas” allows the researcher to evaluate the polymorphism of each accession and the diversity within the collection. Gliadin analysis was performed on single grains according to the standard method adopted at VIR and approved by ISTA.

Results and conclusions. Fourteen major biotypes marked with gliadin bands were identified. Depending on the component composition of the α-zone encoded by alleles of the GLI-2A locus, biotypes were combined into 4 groups. Within the groups, biotypes are determined by alleles of the GLI-1A, GLI-1B, GLI2B loci. Genetically close monotypic accessions and polytypic ones incorporating 2 to 6 biotypes were identified. Group I is typical for the European part of Russia as well as for Kazakhstan and Kyrgyzstan. Accessions of this group can be attributed to the Volga steppe ecotype. Group II biotypes are widespread in Altai Territory, Orenburg and Astrakhan Provinces of Russia; Group III in Stavropol Territory, Russia, and Kyrgyzstan; Group IV only in Altai Territory. The greatest genetic diversity was exhibited by the ‘Kubanka’ accessions from Altai and Krasnodar Territories, and Kyrgyzstan. 

At Krymsk Experiment Breeding Station of VIR, as a result of collecting, studying, and selective use of myrobalan plum genetic diversity, the intraspecific taxonomy of the species Prunus cerasifera Ehrh. was clarified. Donors of traits significant for breeding were identified and, with their use, adaptable cultivars of myrobalan plum, Russian plum and clonal rootstocks of stone fruit plants were developed.

Intraspecific classification of P. cerasifera is proposed, with the identified subspecies:

subsp. cerasifera (typical myrobalan plum);

subsp. orientalis (M. Pop.) Erem. et Garcov. (Oriental myrobalan plum);

and subsp. macrocarpa Erem. et Garcov. (large-fruited myrobalan plum).

Within subsp. P. cerasifera subsp. macrocarpa, varieties were identified:

var. macrocarpa (typical, or Krymsk);

var. georgica Erem. et Garcov. (Georgian);

var. iranica (Koval.) Erem. et Garcov. (Iranian);

var. nairica (Koval.) Erem. et Garcov. (Armenian);

var. pissardii Carr. (Pissard);

and var. taurica (Kost.) Erem. et Garcov. (Taurida).

The participation of myrobalan plum in the origin of spp. P. brigantiaca Vill., P. cocomilia Tem., and P. spinosa L. was traced. Involvement of large-fruited myrobalan plum in hybridization with blackthorn contributed to the manifestation of an exceptional polymorphism among the varieties of the hybridogenic species P. domestica L. (P. cerasifera × P. spinosa). As a result of hybridization between myrobalan plum and Chinese plum varieties, a new cultigen species emerged – Russian plum (× P. rossica Erem.). By now, 127 cultivars of this species and 7 clonal rootstocks for stone fruit crops have been developed. These cultivars and clonal rootstocks are zoned for Russia and a number of other countries. 

Two widespread weedy species of Urtica L. (Urticaceaea Juss.), common nettle (Urtica dioica L.) and annual nettle (U. urens L.), possess many useful properties, so any information on their distribution is of practical interest. Numerous scientific publications with open access were used to map the areas of distribution for these species in the Russian Federation. While mapping the spatial arrangement of these taxa, the data on the frequency of their occurrence in separate administrative subdivisions of the country were employed. Areas where occurrences of an individual nettle species are scored as “very often”, “often”, “usually” or “often” were blended into one territory characterized with the “often” occurrence: this is the optimum zone for the species in question. Similarly, the pessimum zone for the species was identified as a combined territory of the areas where the occurrence was marked as “very rarely”, “rarely”, “infrequently” or “sporadically”. The pessimum zone included the areas located in the north of the range of species distribution: they are characterized by cooler and more humid environmental conditions than the optimum zone. The pessimum also incorporated the lands stretching in the southern part of the range: their environmental conditions are drier and warmer than those in both the optimum zone and the northern part of the pessimum zone. Therefore, plants of the same species, occurring in different parts of their area of distribution, are adapted to different hydrothermal conditions, which should be taken into account when selecting forms for further possible cultivation and use.

Background. Heracleum sosnowskyi Manden. (family Umbelliferae = Apiaceae) is included in the lists of invasive species in many regions of Russia and European countries. Mericarps (fruits conventionally called seeds) of Heracleum L. spp. are characterized by an underdeveloped embryo and a complex morphophysiological type of dormancy; two-stage stratification is needed for their germination.

Methods. In the period from 2014 to 2019, fruits of H. sosnowskyi were collected near settlements in Vyborg and Gatchina Districts, Leningrad Province; collecting was carried out from August through March. Seed size and 1000 seed weight were measured. Germination experiments were performed in the laboratory (22–24°C) monthly, from the time of collection in August until May. Seeds were germinated in Petri dishes on filter paper with three replications.

Results. Large seeds on marginal umbellules of the central umbel were the largest in size. Their length was from 0.6 to 1.4 cm, width from 5 to 11 mm, and 1000 seed weight from 9 to 18 g. The length of smaller fruits was from 7 to 9 mm, width from 3 to 5 mm, and 1000 seed weight from 10.5 to 11.8 g. Germination of seeds collected in late summer was protracted. Under laboratory conditions, the emergence of the first seedlings was observed after 5–7 days. For the fruits stored in the laboratory, germination was reduced. Germination rate of stratified seeds varied from 55 to 99%.

Conclusion. The biometric parameters of H. sosnowskyi mericarps were slightly affected by the place of growth and the year of maturation. Under laboratory conditions, H. sosnowskyi seeds collected in August showed germination rates from 3 to 15%. In years with a warm and long autumn, part of the fruit germinated in the year of maturation and managed to reach their juvenile state. Plump mericarps remained viable for at least three years. Sosnowsky’s hogweed fruits stored under laboratory conditions lost their germination ability within a year.

Background. VIR’s potato collection is one of the oldest and richest; however, it is constantly exposed to viruses that negatively affect useful agronomic properties of tubers. Close monitoring of the phytosanitary state of potato accessions helps to select the most effective method of therapy for subsequent healing of infected plants and obtaining high-quality planting material.

Materials and methods. The research was aimed at improving the health of 18 varieties of Solanum tuberosum L. from the VIR collection. Testing for the presence of viruses was based on the ICA and RTPCR techniques, and the consequent healing was performed using the methods of meristem culture and cryotherapy.

Results and conclusions. During the field test of potato plants, PVX, PVS and PVA were found to be the most common viruses. PSTVd was completely absent in all tested accessions. The effectiveness of in vitro healing of potato plants from viruses was assesses using meristem culture. The percentage of healed plants was 0% for PVS, 0% for PVX, 33.4% for PVA, 50% for PLRV, 72.3% for PVY, and 83.4% for PVM. Healing with meristem culture was shown to be the most effective against PVY and PVM. While assessing the effectiveness of post-cryogenic restoration of potato microplants, the level of post-cryogenic regeneration of the shoot tips in potato microplants was determined at 22.3% on average for a sample. The minimum was observed in k-16762 ‘Sagita N’ (5%), and the maximum in k-1378 ‘Marta’ (41.7%). Analysis of the effectiveness of potato recovery from viruses by in vitro cryotherapy showed that the percentage of recovered plants was 100% for PVY, 100% for PVA, 88.9% for PVM, 77.8% for PVS, 44.4% for PVX. Thus, the techniques of apical meristem culture and cryotherapy proved to be effective against PVY, PVA and PVM viruses. However, in the case of multiple infections, it is necessary to combine elements of different healing protocols to increase the effectiveness of the healing procedure. 

Background. Predominant use of the H1 and Gro1-4 genes of resistance to golden nematode (PGN) in potato breeding requires widening the gene pool of resistance to this pathogen.

Materials and methods. Thirty-four genotypes of wild potatoes from North and South Americas, 14 interspecific hybrids, and 10 Russian potato cultivars were studied for PGN resistance. Screening for resistance to PGN pathotype Ro1 and molecular screening for the presence of H1 and Gro1-4 gene markers were performed. Amplification products of the Gro1-4 gene marker were sequenced.

Results. Only seven among the studied 34 potato genotypes (two of S. brachystotrichum (Bitt.) Rydb., four of S. lesteri Hawkes et Hjerting, and one of S. kurtzianum Bitt. et Wittm.) were susceptible to PGN, while the rest demonstrated high or medium resistance. Molecular screening for the presence of H1 and Gro1-4 gene markers allowed us to identify Gro1-4 in 13 South American genotypes of S. alandiae Cárd., S. × doddsii Corr., S. kurtzianum, S. leptophyes Bitt., and S. yungasense Hawkes. The remaining 14 genotypes may supposedly contain resistance genes non-identical to H1 or Gro1-4. Hybrids of S. tuberosum L. with medium-resistant wild accessions of S. kurtzianum, S. leptophyes, S. sparsipilum (Bitt.) Juz. et Buk., S. alandiae, and S. × doddsii inherited PGN resistance determined either by the Gro1-4 gene or genes non-identical to H1 or Gro1-4. Sequencing a fragment of the Gro1-4 gene showed that changes in the structure of this fragment in orthologous genes did not affect the feature of resistance to PGN pathotype Ro1.

Conclusion. For the first time, sources of resistance to PGN were found among the North American species S. brachystotrichum (k-23201) and S. lesteri (k-24475). Among the wild South American Solanum spp., sources of resistance determined by genes different from H1 or Gro1-4 were identified. Resistant interspecific hybrids can serve as donors of the Gro1-4 resistance gene or new resistance genes. 

Background. Clonal apple rootstocks are one of the main components of intensive gardening. The degree of rootstock damage by fire blight affects the resistance of the variety–rootstock combination. The paper presents a study on marking quantitative trait loci (QTL) of resistance to fire blight Erwinia amylovora in clonal apple rootstock.

Materials and methods. A collection of 20 rootstock forms was analyzed. For the study, SCAR markers GE-8019, AE10-375 and microsatellite marker CH-F7-FB1 were used.

Results. Polymorphism was observed for all three markers, and their various combinations in one genotype were revealed. It was previously noted that genotypes that carry all three markers were more resistant than those that lack them. The presence of all three markers was observed only in forms 62-396 (В10), 16-1 and 2-9-102. The other genotypes did not have the GE8019 marker. The AE10-375 marker was identified in eight clonal rootstocks. Microsatellite marker CH-F7-FB1 was present in all tested rootstocks. However, polymorphism was detected there. Most genotypes had a 174 bp fragment, but a 210 bp fragment was identified in two of the 20 forms. Clonal rootstock 70-20-21 proved heterozygous for this marker. The analyzed collection also included samples that had only the microsatellite marker: G16, Malysh Budagovskogo, Paradizka Budagovskogo (B9), 54-118 (В118), 57-491, 70-20-20 (В119), 70-20-21, 71-7-22, 76-3-6, 83-1-15, 87-7-12, and 2-12-10. The study of rootstock forms on the basis of resistance to metabolites of the fire blight pathogen was carried out under laboratory conditions using the E. amylovora culture filtrate in vitro on leaf explants. Most of the studied genotypes had different combinations of markers. However, the experiments showed that forms 62-396 and 14-1 with two out of three markers (AE10-375 and CH-F7-FB1) phenotypically manifested the trait of resistance to metabolites of E. amylovora. 

An effective way to increase the genetic diversity of plants and create sources of resistance to edaphic stressors is the selection of cells under selective in vitro conditions based on somaclonal variation. The use of somaclones (regenerant forms) of barley with resistance to increased acidity, ionic toxicity of aluminum, heavy metals and drought is promising in the northeast of the Non-Black-Soil Zone of Russia. Development of regenerants with integrated resistance to soil stressors due to specific and nonspecific mechanisms is a relevant trend.

The target research material was a hybrid combination of spring barley (Luly × Conrad) × 2867-80 and its regenerant forms obtained as a result of cell selection with stressors of various nature. Plants were grown under ordinary soil conditions and on provocative backgrounds with aluminum and cadmium. The productive traits of plants, the symptoms of oxidative stress, and the environment-forming activity of the root system were evaluated.

In regenerated plants obtained in callus culture on selective in vitro media with aluminum or water deficiency, an increased ability of the root system to alkalize the medium in the rhizosphere zone (by 0.2–0.5 pH units) when grown on alumina soil was revealed. Against stressful soil backgrounds, regenerative lines induced on in vitro media with cadmium or aluminum were observed to have a low manifestation of oxidative stress symptoms, tested by the intensity of lipid peroxidation and the content of photosynthetic pigments in the leaves, which provided these genotypes with higher seed productivity (1.5–3.6 times in the number of grains, and 1.5– 3.0 times in the grain weight per plant) and adaptive advantages compared to the original genotype and regenerants induced on an in vitro medium with water deficiency. It is concluded that complex resistance to soil aluminum and cadmium toxicity is formed in barley regenerants obtained in the process of cell selection on in vitro media with any of these metals. 

The aim of the study was to assess black currant cultivars for yield, environmental plasticity and stability in Chelyabinsk Province. We identified adaptable black currant cvs. ‘Seyanets Druzhnoy’ (4.43 t/ha; AQ = 1.54), ‘Polar’ (3.59 t/ha; 1.38), ‘Venera’ (4.48 t/ha; 1.35), ‘Zhemchuzhina’ (4.49 t/ha; 1.34), ‘Sudarushka’ (4.43 t/ha; 1.30), ‘Bolero’ (3.42 t/ha; 1.20), ‘Gera’ (3.97 t/ha; 1.16), ‘Mortti’ (3.46 t/ha; 1.06), ‘Podarok Ilyinoy’ (3.89 t/ha; 1.03), ‘Selva’ (3.21 t/ha; 1.02) and ‘Mayak’ (3.54 t/ha; 1.01). The most interesting are intensive-type cultivars, capable of significantly increasing their productivity with the improved growing conditions. Intensive-type cultivars developed in Chelyabinsk are cvs. ‘Podarok Ilyinoy’, ‘Sudarushka’, ‘Zhemchuzhina’, ‘Gera’, ‘Mayak’ and ‘Venera’ (b_i = 1.70, 1.68, 1.52, 1.46, 1.40, and 1.28, respectively).

The locally developed cv. ‘Seyanets Druzhnoy’, environmentally plastic but insufficiently stable (b_i = 1.17; S_i² = 6.1), exceeded in its average yield the environmentally plastic and stable cvs. ‘Selva’ (bi = 0.77; S_i² = 0.7) and ‘Mortti’ (b_i = 0.93; S_i² = 1.1). Cv. ‘Bolero’ developed by the Vavilov Institute (VIR) and the Swedish cv. ‘Polar’ are neutral, i.e., they weakly respond to changes in cultivation conditions. High yields were recorded for cvs. ‘Zhemchuzhina, ‘Venera’, ‘Sudarushka’, ‘Seyanets Druzhnoy’, ‘Gera’, ‘Podarok Ilyinoy’, ‘Polar’, ‘Mayak’, ‘Mortti’ and ‘Bolero’.

The yield of the following cultivars was at the average level for the experiment: ‘Rusalka’ (b_i = 1.50), ‘Orloviya’ (b_i = 1.56), ‘Pigmey’ (b_i = 1.30), plus the yield (3.36 to 3.25 t/ha) of environmentally stable cvs. ‘Legenda’ (b_i = 1.24; S_i² = 0.3), ‘Kama’ (b_i = 1.00; S_i² = 0.8), and ‘Dochka’ (b_i = 1.15; S_i² = 0.5). Cvs. ‘Zem Zarin’ (1.79 t/ha), ‘Chernecha’ (1.82 t/ha), ‘Zorya Galitskaya’‚ (2.18 t/ha), ‘Sibilla’ (2.37 t/ha), ‘Krasa Lvova’ (2.52 t/ha) and ‘Shakhalevskaya’ (2.84 t/ha) demonstrated yield levels significantly lower than the average. 

Excessive soil acidity is one of the main factors causing significant losses in crop production. Using fiber flax, the effect of soil acidity on the yield and fiber quality of various samples representing the world gene pool of this crop is shown. The optimum acidity for fiber flax is within a narrow range – pH_KCl 5.3–5.6. On strongly acid soils (pH_KCl less than 4.5) with threshold values of the toxic aluminum (Al³⁺) content, 10–11 mg/100 g, a decrease in the flax yield is over 50%. Currently, along with the mechanisms of detoxification of toxic aluminum in acid soils, genetic aspects of aluminum resistance have also been determined. It is shown that one of the most significant components of the common defense response of plants to various stresses is their antioxidant systems. An important role in the antioxidant defense system belongs to glutathione transferases. Using high-through put sequencing and quantitative PCR, a change in the expression of genes and microRNAs in flax plants was revealed in response to the toxic effect of aluminum ions. Using flax genotypes contrasting in acid resistance, an increase in the expression of genes encoding UDP-glycosyltransferases (UGT) and glutathione-S-transferases (GST) was established under aluminum stress. The increase in expression was more pronounced in aluminum-resistant flax cultivars than in sensitive ones. Also, the differences in the change of miR390 and miR393 expression between resistant and sensitive genotypes were revealed under the toxic effects of aluminum ions. Understanding the resistance mechanisms makes it possible to accelerate the development of flax and other crop cultivars adaptive to edaphic stress, which is important for obtaining high and guaranteed yields of agricultural products.

The review gives an insight into amaranth, a very promising crop for the whole world. This crop has a long history dating back to the days of the Aztecs and Incas, for whom it was one of the most important crops, along with corn. However, unlike the latter, amaranth lost its nutritional value after being introduced into Europe. Only in the 20th century, largely thanks to Nikolai Vavilov, amaranth attracted great interest as a food and feed crop. Amaranth is a plant unique in its nutritional properties. It is characterized by a high content of protein saturated with essential amino acids, especially lysine, and a large number of bioactive compounds, such as vitamin C, amaranthine, rutin, carotenoids, etc. Of particular value is grain oil saturated with various lipid compounds: squalene, vitamin E, phytosterols, and fatty acids. These lipid compounds have a number of important properties from the point of view of functional nutrition: as natural antioxidants they bind free radicals, normalize lipid metabolism, and help to decrease blood cholesterol levels. The review focuses on genes that determine the content of the main, valuable biochemical components: squalene, vitamin C, and lysine. The genetic pathways that control the biosynthesis of these components have been studied in detail in various model plant objects. The presence of the complete genomic sequence of Amaranthus hypochondriacus L. makes it possible to identify orthologs of key biosynthetic genes. At the moment, only few genes in amaranth have been identified, including the squalene synthase (SQS) gene, the VTC2 ascorbic acid synthesis gene, and the key genes for lysine synthesis – AK and DHDPS. The article discusses the prospects and trends of marker-assisted selection of this crop as well as the difficulties of its systematization and genotyping, which have to be overcome to successfully solve plant breeding problems.

This publication explores the history of personal contacts and correspondence between the distinguished biochemist V. I. Nilov and the writer Maxim Gorky in 1933–1936. Through out his life, M. Gorky tried to use his influence to help talented scientists as well as scientific and cultural institutions. In 1933, V. I. Nilov, a researcher from the Nikita Botanical Gardens, wrote to Gorky about the experiments he performed in his biochemistry lab on the synthesis of vitamin C, plant breeding for chemical composition, and isolation of opiates from poppy. The writer appealed to the USSR top officials, intending to improve the situation with scientific institutions in Crimea. As a result of Gorky’s mediation efforts, Nilov’s documents were presented to I. V. Stalin. The leaders of the USSR were interested in such research, because it complied with the country’s strategic objectives. This, in its turn, led to changes in vitamin research and production in the USSR and had an effect on the status of the Nikita Botanical Gardens. V. I. Nilov’s scientific biography was closely interlinked with the history of the Institute of Plant Industry and its director N. I. Vavilov. By this publication, earlier unknown materials from the Archive of A.M. Gorky (Institute of World Literature, Moscow) and the Russian State Archive of Socio-Political History (Moscow) are for the first time introduced into public scientific discourse.