Resistance of oat breeding lines to grain contamination with Fusarium langsethiae and T-2/HT-2 toxins

Fusarium disease of oats reduces yield quality due to decreasing germination that is caused by then contamination of grain with mycotoxins produced by Fusarium fungi. The aim of this study was to characterize the resistance of naked breeding lines of oats to fungal grain infection and to contamination with T-2 and HT-2 toxins. Thirteen naked oat breeding lines and two naked varieties, Nemchinovsky 61 and Vyatskiy, as well as a husked variety Yakov, were grown under natural conditions in the Nemchinovka Federal Research Center in 2019–2020. The contamination of grain with fungi was determined by the mycological method and real-time PCR. The analysis of mycotoxins was carried out by ELISA. In oats, Alternaria (the grain infection was 15–90 %), Cochliobolus (1–33 %), Cladosporium (1–19 %), Epicoccum (0–11 %), and Fusarium (3–17 %) fungi prevailed in the grain mycobiota. The predominant Fusarium species were F. poae (its proportion among Fusarium fungi was 49–68 %) and F. langsethiae (29–28 %). The highest amounts of F. langsethiae DNA ((27.9–71.9)×10–4 pg/ng) and T-2/HT-2 toxins (790–1230 μg/kg) were found in the grain of husked oat Yakov. Among the analysed naked oat lines, the amount of F. langsethiae DNA varied in the range of (1.2–42.7)×10–4 pg/ng, and the content of T-2/HT-2 toxins was in the range of 5–229 μg/kg. Two oat breeding lines, 54h2476 and 66h2618, as well as a new variety, Azil (57h2396), can be characterized as highly resistant to infection with Fusarium fungi and contamination with mycotoxins compared to the control variety Vyatskiy.

Wheat, Barley, and Oat Breeding for Health Benefit Components in Grain

Cereal grains provide half of the calories consumed by humans. In addition, they contain important compounds beneficial for health. During the last years, a broad spectrum of new cereal grain-derived products for dietary purposes emerged on the global food market. Special breeding programs aimed at cultivars utilizable for these new products have been launched for both the main sources of staple foods (such as rice, wheat, and maize) and other cereal crops (oat, barley, sorghum, millet, etc.). The breeding paradigm has been switched from traditional grain quality indicators (for example, high breadmaking quality and protein content for common wheat or content of protein, lysine, and starch for barley and oat) to more specialized ones (high content of bioactive compounds, vitamins, dietary fibers, and oils, etc.). To enrich cereal grain with functional components while growing plants in contrast to the post-harvesting improvement of staple foods with natural and synthetic additives, the new breeding programs need a source of genes for the improvement of the content of health benefit components in grain. The current review aims to consider current trends and achievements in wheat, barley, and oat breeding for health-benefiting components. The sources of these valuable genes are plant genetic resources deposited in genebanks: landraces, rare crop species, or even wild relatives of cultivated plants. Traditional plant breeding approaches supplemented with marker-assisted selection and genetic editing, as well as high-throughput chemotyping techniques, are exploited to speed up the breeding for the desired genotуpes. Biochemical and genetic bases for the enrichment of the grain of modern cereal crop cultivars with micronutrients, oils, phenolics, and other compounds are discussed, and certain cases of contributions to special health-improving diets are summarized. Correlations between the content of certain bioactive compounds and the resistance to diseases or tolerance to certain abiotic stressors suggest that breeding programs aimed at raising the levels of health-benefiting components in cereal grain might at the same time match the task of developing cultivars adapted to unfavorable environmental conditions.

Localization of the Stem Rust Resistance Gene Pg2 to Linkage Group Mrg20 in Cultivated Oat (Avena sativa)

Stem rust is an important disease of cultivated oat (Avena sativa) caused by Puccinia graminis f. sp. avenae. In North America, host resistance is the primary strategy to control this disease and is conferred by a relatively small number of resistance genes. Pg2 is a widely deployed stem rust resistance gene that originates from cultivated oat. Oat breeders wish to develop cultivars with multiple Pg genes to slow the breakdown of single gene resistance, and often require DNA markers suited for marker-assisted selection. Our objectives were to (i) construct high density linkage maps for a major oat stem rust resistance gene using three biparental mapping populations, (ii) develop Kompetitive allele-specific PCR (KASP) assays for Pg2-linked single-nucleotide polymorphisms (SNPs), and (iii) test the prediction accuracy of those markers with a diverse panel of spring oat lines and cultivars. Genotyping-by-sequencing SNP markers linked to Pg2 were identified in an AC Morgan/CDC Morrison recombinant inbred line (RIL) population. Pg2-linked SNPs were then analyzed in an AC Morgan/RL815 F2 population and an AC Morgan/CDC Dancer RIL population. Linkage analysis identified a common location for Pg2 in all three populations on linkage group Mrg20 of the oat consensus genetic map. The most predictive markers were identified and converted to KASP assays for use in oat breeding programs. When used in combination, the KASP assays for the SNP loci avgbs2_126549.1.46 and avgbs_cluster_23819.1.27 were highly predictive of Pg2 status in panel of 54 oat breeding lines and cultivars.

Yerel Yulaf (Avena sativa L.) Genotiplerinin Eskişehir Koşullarında Tane Verimi ve Bazı Kalite Özellikleri

Oat breeding activities at the Transitional Zone Agricultural Research Institute (TZARI) have been continuing since 1929. Within the scope of this study, it is aimed to select those that are high in yield and quality from local oat lines that are compatible with regional conditions and to register them as new oat cultivars. Field trials were conducted in rainfed conditions in Eskişehir TZARI Central and Hamidiye Campuses in the 2017-2018 crop season. In the study, ninehteen local lines (Avena sativa L.) collected from different parts of the country and Checota, Kahraman, Kırklar, Yeniçeri and Sebat varieties as a standard were used. In this research, besides various agro-morphological traits such as grain yield (GY), thousand kernel weight (TKW), plant height (PH), lodging score (LS), heading days (HD), grain protein content (PC), beta-glucan (BG), acid detergent fiber (ADF) and neutral detergent fiber (NDF) values were examined. According to the results of this study, differences between genotypes in parameters other than ADF and NDF values were found statistically significant. The means of grain yield was 2,93 t ha-1, and the GY of genotypes was ranged from 2,31 to 3,58 t ha-1 in the trial. TKW was ranged from 25,5 to 37,1g; PH was 83,3 to 130,2 cm; HD was 126,0 to 141,0 days; BG was 3,29 to 5,16%; PC was 13,4 to 15,9%; ADF was 16,4 to 19,4%; NDF was 30,8- 38,8% in the genotypes. Accordingly, G13, G16, G19, G21,G22 and G23 local oat lines have been found to be promising in terms of targeted agro-morphological and quality characteristics and transferred to advanced level in the oat breeding program.

The Screening of Resistance against Meloidogyne graminicola in Oats

Including pest resistance elements against the major local concern is naturally important in the breeding process. Oat (Avena sativa L.) has been recently reintroduced into Taiwan as a winter alternative forage crop, and its agronomic performance has been evaluated at different locations in the country. This study examined the resistance to root-knot nematode, Meloidogyne graminicola, in four oat (Avena sativa L.) breeding lines of mass planting potential for winter in Taiwan. The host attraction level to the nematode, and the penetration and reproduction ability of nematode towards host roots were evaluated by chemotaxis assay, root staining assay, root galling, and nematode extraction. Based on the gall index (GI) and multiplication factor (R), the resistance of each oat line was evaluated. At 24 h postinoculation, second-stage juvenile (J2) nematodes appeared most attracted by oat breeding lines UFRGS136104-3 and UFRGS136119-2. The number of J2s successfully penetrated into the two breeding lines were also high. However, at 40 days postinoculation, observation of the oats in the newly developed culture bag nematode-inoculation system revealed that the amount of root galls and 2nd generation nematodes were significantly higher in line LA08085BS-T2 than in other lines. In sum, oat breeding line UFRGS136104-3 was highly resistant to M. graminicola by inhibiting the gall formation and nematode reproduction, while UFRGS136106-3 and UFRGS136119-2 showed relatively weak resistance and oat line LA08085BS-T2 would be a moderately susceptible host to M. graminicola, with high numbers of root gall formation. The outcome of this study provides ground information for nematode-resistant oat cultivar breeding.

Mycobiota in Mycobiota in the grain of the oat breeding lines produced in 2019 in competitive variety trials on the fields of Nemchinovka Federal Research Center, Moscow Provincepetitive variety trials on the fields of Nemchinovka Federal Research Center, Moscow Province

Background. The requirement for high-quality oat grain for food production leads to the need for studying the resistance of this cereal crop to harmful diseases and for the development of new productive cultivars.Materials and methods. A comparative characterization was performed among the breeding lines of naked oats from Nemchinovka Federal Research Center according to the parameters of microbiological purity of grain. The mycological method was applied for the analysis of infection in the oat grain, and fungal species composition was identified. The DNA amount of toxin-producing species from genus Fusarium Link in the grain was detected using the real-time PCR, and the amount of mycotoxins was measured by the enzyme immunoassay.Results. The fungi of Alternaria Nees, Fusarium, Cladosporium Link, Cochliobolus Drechsler, Epicoccum Link were associated with oat grain. Uniquely high infection of the grain by F. langsethiae Torp & Nirenberg (14%) was found under the natural conditions of the Central Region of Russia. The differences revealed among the analyzed breeding lines and cultivars in the DNA amount of F. langsethiae and F. sporotrichioides Sherb. were from 1.3×10-4 to 7.2×10-3 pg/ng in the total DNA, and from 5 to 1230 μg/kg in the content of T-2/ HT-2 toxins.Conclusion. All naked oat breeding lines were relatively resistant to Fusarium infection and proved the best as regards the mycotoxin contamination of the grain against the reference hulled cultivar ‘Yakov’. In the competitive variety trials, three lines – 66h2618, 54h2476 and 70h2613 – were characterized as relatively resistant to Fusarium disease, compared with the naked oat reference ‘Vyatsky golozerny’.

Mapping of the Oat Crown Rust Resistance Gene Pc39 Relative to Single Nucleotide Polymorphism Markers

Crown rust, caused by Puccinia coronata f. sp. avenae Eriks. (Pca), is among the most important oat diseases resulting in significant yield losses in many growing regions. A gene-for-gene interaction is well established in this pathosystem and has been exploited by oat breeders to control crown rust. Pc39 is a seedling crown rust resistance gene that has been widely deployed in North American oat breeding. DNA markers are desired to accurately predict the specific Pc genes present in breeding germplasm. The objectives of the study were as follows: (i) to map Pc39 in two recombinant inbred line (RIL) populations (AC Assiniboia/MN841801 and AC Medallion/MN841801) and (ii) to identify single nucleotide polymorphism (SNP) markers for postulation of Pc39 in oat germplasm. Pc39 was mapped to a linkage group consisting of 16 SNP markers, which placed the gene on linkage group Mrg11 (chromosome 1C) of the oat consensus map. Pc39 cosegregated with SNP marker GMI_ES01_c12570_390 in the AC Assiniboia/MN841801 RIL population and was flanked by the SNP markers avgbs_126086.1.41 and GMI_ES15_c276_702, with genetic distances of 1.7 and 0.3 cM, respectively. In the AC Medallion/MN841801 RIL population, similar results were obtained but the genetic distances of the flanking markers were 0.4 and 0.4 cM, respectively. Kompetitive Allele-Specific PCR assays were successfully designed for Pc39-linked SNP loci. Two SNP loci defined a haplotype that accurately predicted Pc39 status in a diverse panel of oat germplasm and will be useful for marker-assisted selection in oat breeding.

Breeding value of european oat accessions in the environments of Kuban experiment station of VIR

Background. For the present-day oat breeding, the task is to develop adaptive cultivars with high yield potential, high quality of products, fairly early-ripening habit, and resistance to lodging and diseases. Breeding new cultivars with a complex of valuable characters, high yield, and high quality of products under varied environmental conditions requires well-studied source material. Selection of sources according to the basic economically useful traits is one of the main objectives in the study of the global diversity preserved in the oat collection.Results and conclusion. The article presents the results of studying the oat accessions from Western and Central European countries, preserved in the VIR collection, under the conditions of Kuban Experimental Station of VIR (Krasnodar Terr.). Evaluation of the accessions in the field was targeted at such crop characters as the duration of the growing season, resistance to lodging, and field resistance to rust diseases. A structural analysis was performed in the laboratory to measure the weight of 1000 grains, the number of spikelets and grains per panicle, grain weight per panicle and per plant, and percentage of grain hullness. As a result of a three-year comprehensive field study of the newest oat cultivars bred in Western Europe in the environments of Kuban Experimental Station of VIR, sources of traits useful for breeding were identified, such as lodging resistance, field resistance to crown rust, high yield structure components (1000 grain weight, grain weight per panicle, number of grains per panicle, grain productivity). When using source materials in oat breeding practice, in addition to economically important traits, special attention should be paid to grain size, since this character, according to our data, has the most significant correlation with the grain yield of a cultivar. The identified sources of traits valuable for breeding may be included in breeding programs of Krasnodar Territory and other regions of the Russian Federation.