Gamma (γ)-irradiation of plants at low doses can provoke a broad range of growth-stimulating effects. In order to reveal universal target genes that are involved in molecular pathways of radiation hormesis establishment, we studied nine barley cultivars for their tolerance to γ-irradiation of seeds. Four morphological traits were assessed in barley seedlings after γ-irradiation of seeds at 20 Gy. Nine cultivars were sorted according to the sensitivity to irradiation as γ-stimulated, “no morphological effect”, or γ-inhibited. Gene expression of 17 candidate genes was evaluated for the 7 most contrasting cultivars. Changes in expression of barley homologues of PM19L and CML31 were suggested as possible determinants of radiation hormesis effect. The possible role of jasmonate signaling in roots in radiation growth stimulations was revealed. Morphological analysis and gene expression study showed that the genetic background of a cultivar plays an important role in eustress responses to low-dose γ-irradiation of seeds.

Low-dose γ-irradiation can stimulate plant growth and development; however, the knowledge on the molecular mechanisms of such stimulation is yet fragmented. Irradiation of seeds leads to the mobilisation of endosperm resources and reallocation of available nitrogen to facilitate development. Based on the metabolomic analysis, several metabolites possibly involved in radiation stimulation were studied using the HPLC approach in barley cultivars after γ-irradiation of seeds. The comparison of changes in metabolite concentrations and changes in morphological traits after irradiation revealed seven metabolites that may be involved in the growth stimulation after γ-irradiation of barley seeds. Among them are free amino acids, such as γ-aminobutyric acid, β-alanine, arginine, lysine, glutamine, methionine, and a signalling compound methylglyoxal.

Barley is the main forage crop in the Russian Federation. Barley grain is also used for food and brewery (Filippov, 2013). It is common knowledge that low doses of gamma irradiation can have a stimulating effect on the growth and development of plants, in particular barley. However, there is a lack of knowledge about the molecular pathways responsible for the formation of the stimulation effect after low-dose seed irradiation. The use of varieties with different radio sensitivity to low-dose gamma irradiation will allow studying specific molecular mechanisms to form a stimulating irradiation effect. Such knowledge could further help in the development of varieties with a large stable productivity over the years and with high resistance to biotic and abiotic stressors. In 2019 there was conducted a gamma irradiation of the original seeds of nine winter and spring barley varieties developed in the FSBSI “Agricultural Research Center “Donskoy” in order to assess intensity of the response on low-dose ionizing irradiation based on changes in the morphological parameters of irradiated and unirradiated plants. The original seeds of each barley variety were irradiated at the FSBSI “All-Russian Research Institute of Radiology and Agroecology” by the gamma device “GUR-120” with 60Со radiation sources at a dose of 20 Gy (dose rate of 60 Gy/hour). The statistical data processing was performed by the Microsoft Office Excel 2019. The morphological analysis of the length and weight of roots and sprouts made it possible to establish the presence or absence of the stimulating irradiation effect on the studied indicators of the varieties and to conduct their subsequent ranking according to the value of the radiobiological effect. There have been identified the winter and spring barley varieties with different sensitivity to a dose of 20 Gy. The stimulating irradiation effect was established in such varieties as “Foks 1”, “Ratnik”, “Yerema” and “Master”. The variety “Leon” had an inhibitory irradiation effect.

In recent decades, the demand for naked barley grain on the market has increased, that is why the breeders of the leading institutions of the Russian Federation resumed breeding research to develop new naked barley varieties. In this regard, the purpose of the current study was to develop a breeding material for naked spring barley, adapted to the conditions of the Rostov region and, on its basis, new varieties. There have been developed the new naked barley variety with high productivity and grain quality, adapted to the conditions of the North Caucasus. The study was carried out in the scientific crop rotation of the department of barley breeding and seed production of the FSBSI Agricultural Research Center “Donskoy” (Zernograd) in 2014–2020. Based on the best local spring barley varieties (‘Leon’ and ‘Shchedry’) and naked varieties of the VIR collection (‘Mancuria’ (Sweden), ‘NB-OWA’ (Nepal), ‘CDC-Dawn’ (Canada), ‘K-3780’ (Tajikistan) and ‘Golozerny’ (RF)) there have been developed and studied the new naked barley lines. There was found that according to the trait ‘plant height’ the lines ‘Leon x Golozerny’ and ‘Leon x Mancuria’ belonged to the middle-height group (90.2 cm and 83.4 cm, respectively). The rest of the lines belonged to the tall group, their height varied from 96.5 cm to 100.3 cm. According to the trait ‘earing date’ there has been identified the line ‘Leon x Golozerny’ (24V), which is more early-ripening (5 days less than that of the standard). The same line turned out to be the only one that significantly exceeded the standard (the standard variety ‘Ratnik’ on 4.5 t/ha) according to productivity +0.3 t / ha, and taking into account the absence of hulls, this difference significantly increased to +0.7 t/ha. There was established that according to the trait ‘1000-grain weight’, the lines ‘Leon x Mancuria’, ‘Leon x CDC-Dawn’, ‘Leon x K-3780’ and ‘Leon x Golozerny’ significantly exceeded the standard variety. The best indicators of grain quality were identified for the lines ‘Leon x K-3780’ and ‘Leon x Golozerny’. The lines ‘Leon x Mancuria’ and ‘Leon x Golozerny’ were the most resistant to powdery mildew. The current paper has presented the characteristics of the new naked spring barley variety ‘Zernogradsky 1717’, which has a great productivity and a set of positive economically valuable traits.

Plant breeding plays an important role in increasing grain production and improving its quality. Currently, the de[1]velopment of new ecologically adaptable varieties that can more effectively use the climatic and soil resources of the regions is of great importance. The purpose of the current study was to analyze the parameters of ecological adapt[1]ability and stability of varieties and lines of the competitive variety testing (2018–2020) in the Rostov region. There have been studied five winter barley varieties ‘Timofey’, ‘Erema’, ‘Vivat’, ‘Marusya’, ‘Foks 1’ and six winter barley lines ‘Pallidum 1899’, ‘Pallidum 1972’, ‘Parallelum 1976’, ‘Parallelum 1979’, ‘Parallelum 1980’, ‘Parallelum 1981’ developed by the FSBSI “ARC “Donskoy”. The sowing was carried out with a Wintersteiger Plotseed seeder, accounting plots area was 10 m². The forecrop was peas. The placement was systematic; the number of repetitions was 6. The factor ‘year’ had the greatest influence on the formation of productivity with 97.07%. The analysis of environmental condi[1]tions showed that there were more favorable growing conditions in 2018 (Ij = +1.27), and unfavorable ones in 2019 (Ij = -1.62). The productivity of the varieties ‘Erema’ (9.4 t / ha; +0.7), ‘Marusya’ (9.7 t / ha; +1.0) and the line ‘Pallidum 1972’ (9.4 t / ha; +0.7) exceeded that of the standard variety. There has been established the varieties and lines ‘Timofey’, ‘Pallidum 1972’, ‘Parallium 1979’, ‘Parallum 1981’ had increased stress resistance. The varieties ‘Erema’, ‘Marusya’ and the line ‘Pallidum 1972’ had a higher compensatory ability. According to the analysis of adaptability, the varieties ‘Erema’, ‘Marusya’, ‘Foks 1’, as well as the line ‘Parallelum 1976’ were identified as responsive with linear regression coefficient values above one. The lines ‘Pallidum 1972’, ‘Parallelum 1979’, ‘Parallelum 1981’ and the variety ‘Marusya’ consistently produced high yields. The lines ‘Pallidum 1972’, ‘Parallum 1979’ and ‘Parallum 1981’ possessed high stability index (L) and PUSS index.