Development and characterization of a line with substitution of chromosome 4B of wheat Triticum aestivum L. on chromosome 4Hmar of wild barley Hordeum marinum ssp. gussoneanum (4x).

Introgressive hybridization is the main method of broadening the genetic diversity of bread wheat. Wild barley Hordeum marinum ssp. gussoneanum Hudson (2n = 4x = 28) has useful agronomical traits, such as high resistance to stress factors, that could be a potential source of new genes for bread wheat improvement. This study aimed to evaluate the possibility of introgression of H. marinum chromosomes into the genome of bread wheat using an incomplete amphiploid H. marinum ssp. gussoneanum (4x)-T. aestivum (Pyrotrix 28) (2n = 54) carrying the cytoplasm of wild barley. For this purpose, we crossed the line of bread wheat variety Pyrotrix 28 with an incomplete amphiploid, and then selected cytogenetically stable 42-chromosome plants with a high level of fertility in hybrid progeny. Genomic in situ hybridization (GISH) revealed a pair of H. marinum chromosomes in the genome of these plants. C- banding analysis confirmed that bread wheat chromosome 4B was replaced by wild barley chromosome 4Hmar. SSR markers Xgwm368 and Xgwm6 confirmed the absence of chromosome 4B, and EST markers BAWU808 and BAW112 identified chromosome 4Hmar in the genome of the isolated disomic wheat-barley substitution line. The study of this line showed that the substitution of chromosome 4B with chromosome 4Hmar resulted in a change of some morphological traits. It included intense anthocyanin coleoptile coloration, specific for H. marinum, as well as a lack of purple coloration of the ears in the leaf sheath, specific for Pyrotrix 28. Line 4Hmar(4B) showed increased performance for several traits, including plant height, number of spikes and tillers per plant, spikelet and grain number in the main spike, grain number per plant, but it had decreased values of 1000-grain weight compared to wheat. Cytogenetic stability and fertility of line 4Hmar(4B) indicated a high compensation ability of barley 4Hmar for wheat chromosome 4B and confirmed their homeology.

Problems and possibilities of studying malting quality in barley using molecular genetic approaches.

About one-third of the world's barley crop is used for malt production to meet the needs of the brewing industry. In this regard, the study of the genetic basis of malting quality traits and the breeding of malting barley varieties that are adaptive to their growing conditions are relevant throughout the world, particularly in the Russian Federation, where the cultivation and use of foreign malting varieties of barley prevails. The main parameters of malting quality (artificially germinated and dried barley grains) are malt extract, diastatic power, Kolbach index, viscosity, grain protein, wort ß-glucan, free amino nitrogen, and soluble protein content. Most of these components are under the control of quantitative trait loci (QTLs) and are affected by environmental conditions, which complicates their study and precise localization. In addition, the phenotypic assessment of malting quality traits requires elaborate, expensive phenotypic analyses. Currently, there are more than 200 QTLs associated with malting parameters, which were identified using biparental mapping populations. Molecular markers are widely used both for mapping QTL loci responsible for malting quality traits and for performing marker-assisted selection (MAS), which, in combination with conventional breeding, makes it possible to create effective strategies aimed at accelerating the process of obtaining new promising genotypes. Nevertheless, the MAS of malting quality traits faces a series of difficulties, such as the low accuracy of localization of QTLs, their ineffectiveness when transferred to another genetic background, and linkage with undesirable traits, which makes it necessary to validate QTLs and the molecular markers linked to them. This review presents the results of studies that used MAS to improve the malting quality of barley, and it also considers studies that searched for associations between genotype and phenotype, carried out using GWAS (genome-wide association study) approaches based on the latest achievements of high-throughput genotyping (diversity array technology (DArT) and single-nucleotide polymorphism markers (SNPs)).

[Prevalence of VRN1 Locus Alleles among Spring Common Wheat Cultivars Cultivated in Western Siberia].

With the use of allele-specific primers developed for the VRN1 loci, the allelic diversity of the VRN-A1, VRN-B1, and VRN-D1 genes was studied in 148 spring common wheat cultivars cultivated under the conditions of Western Siberia. It was demonstrated that modern Western Siberian cultivars have the VRN-A1a allele, which is widely distributed in the world (alone or in combination with the VRN-B1a and VRN-B1c alleles). It was established that the main contribution in acceleration of the.seedling-heading time is determined by a dominant VRN-A1a allele, while the VRN-A1b allele, on the contrary, determines later plant heading. Cultivars that have the VRN-A1b allele in the genotype are found with a frequency of 8%. It was shown that cultivars with different allele combinations of two dominant genes (VRN-A1a + VRN-B1c and VRN-A1a + VRN-B1a) are characterized by earlier heading and maturing.

[Chromosome composition of wheat-rye lines and the influence of rye chromosomes on disease resistance and agronomic traits].

Identification of the chromosomal composition of common wheat lines with rye chromosomes was carried out using genomic in situ hybridization and 1RS- and 5P-specific PCR markers. It was demonstrated that wheat chromosomes 5A or 5D were substituted by rye chromosome 5R in the wheat-rye lines. It was established that one of the lines with complex disease resistance contained rye chromosome 5R and T1RS.1BL, while another line was found to contain, in addition to T1RS.1BL, a new Robertsonian translocation, T5AS.5RL. Substitution of the wheat chromosome 5A with the dominant Vrn-A1 gene for the Onokhoiskaya rye chromosome 5R led to lengthening of the germination-heading period or to a change in the type of development. A negative influence of T1RS.1BL on SDS sedimentation volume and grain hardness was demonstrated, along with a positive effect of the combination of T1RS. BL and 5R(5D) substitution on grain protein content. Quantitative traits of the 5R(5A) and 5R(5D) substitution lines were at the level of recipient cultivars. A line with two translocations, T1RS.1BL + T5AS.5R1, appeared to be more productive as compared to the line carrying T1RS.1BL in combination with the 5R(5D) substitution.

[Specific features of fertility restoration in alloplasmic lines obtained based on hybridization of self-fertilized offspring of barley-wheat (Hordeum vulgare L. x Triticum aestivum L.) amphiploid with common wheat varieties Saratovskaya 29 and Pyrotrix 28].

The problems of fertility restoration in the progeny of barley-wheat hybrids (H. vulgare x T. aestivum) are explained by incompatibility between the cytoplasm of cultivated barley and the nuclear genome of common wheat. Suitable models for studying these problems are alloplasmic lines that combine the cytoplasm of barley and the nuclear genome of wheat. In this work, the specific features of fertility restoration in alloplasmic common wheat lines (H. vulgare)-T. aestivum were studied depending on the influence of wheat varieties Saratovskaya 29 (Sar29) and Pyrotrix 28 (Pyr28) used to produce these lines. The alloplasmic lines were created using hybrids between the 48-chromosome offspring (Amph1) of the barley-wheat amphiploid H. vulgare (ya-319) x T. aestivum (Sar29) and these wheat varieties. Backcrossing of the Amph1 (2n = 48) x Sar29 hybrid with the wheat variety Sar29 resulted in the complete sterility in the (H. vulgare)-Sar29 line, which suggests the incompatibility of the nuclear genome of the common wheat variety Sar29 with the cytoplasm of H. vulgare. Crossing of Amph1 (2n = 48) with Pyr28 resulted in the restoration of self-fertility in the hybrid with 2n = 44. In the alloplasmic lines (2n = 42) formed based on plants of the self-fertilized generations of this hybrid, the barley chromosomes were eliminated, and recombination between the nuclear genomes of the parental wheat varieties Sar29 and Pyr28 took place. Alloplasmic recombinant lines (H. vulgare)-T. aestivum with different levels of fertility were isolated. As was shown by the SSR analysis, differences in the fertility traits between these lines are determined by variations in the content of the genetic material from the wheat varieties Sar29 and Pyr28. The complete restoration of fertility in these alloplasmic recombinant lines is accompanied by the formation of a nuclear genome in which the genetic material of Pyr28 significantly prevails. The conclusion is made that the common wheat variety Pyrotrix 28 is a carrier of a gene (or genes), which determines the restoration of common wheat fertility on the cytoplasm of cultivated barley.

[Features of alloplasmic wheat-barley substitution and addition lines (Hordeum marinum subsp. gussoneanum)-triticum aestivum].

Two alloplasmic wheat-barley substitution lines were studied: a line replaced at three pairs of chromosomes 1Hmr((IB), 5Hmar(5D), and 7Hmar(7D), and the disomic-substituted line 7Hma(7D). The lines were constructed on the basis of individual plants from BCIF8- and BC2F6 progeny of barley-wheat hybrids (H. marinum subsp. gussoneanum Hudson (=H. geniculatum All.) (2n = 28) x T. aestivum L.) (2n = 42) (Pyrotrix 28), respectively. Moreover, the alloplasmic wheat-barley ditelosomic addition line 7HLma' isolated among plants from the BC1F6 progeny of a barley-wheat amphiploid was studied, which in this work corresponds to BC2F10 and BC2F11 progeny. It was ascertained that when grown in the field, these alloplasmic lines manifest stable self-fertility. Plants of the given lines are characterized by low height, shortened ears, the fewer number of stems and ears, and of spikelets in the ear, by decreased grain productivity and weight of 1000 grains, in comparison with the common wheat cultivar Pyrotrix 28. The inhibition of trait expression in alloplasmic wheat-barley substitution and addition lines may be connected not only with the influence of wild barley chromosomes functioning in the genotypic environment of common wheat, but also with the effect of the barley cytoplasm. The alloplasmic line with substitution of chromosomes 1Hmar(1B), 5Hmar(5D), and 7Hmar(7D) or the alloplasmic line 7HLmar with ditelosomic addition have, in comparison with the common wheat cultivar Pyrotrix 28, an increased grain protein content, which is explained by the effect of wild barley H. marinum subsp. gussoneanum chromosomes.

[Production of alloplasmic and euplasmic wheat-barley ditelosomic substitution lines 7H(1)Lmar(7D) and analysis of the 18S/5S mitochondrial repeat in these lines].

Alloplasmic lines of common wheat with disomic substitution of chromosome 7D for telocentric chromosome 7H(1)Lmar of barley H. marinum subsp. gussoneanum Hudson were isolated from the plants of generation BC3, produced as a result of backcrossing of barley-wheat hybrids H. marinum subsp. gussoneanum (2n = 28) x x T. aestivum (2n = 42), Pyrotrix, cultivar, with 28 common wheat cultivars Pyrotrix 28 and Novosibirskaya 67. Chromosome substitution pattern was determined using SSR analysis and C-banding. In preliminary genomic in situ hybridization experiments, telocentric chromosomes were assigned to wild barley was established. In the BC3F8-generations of three alloplasmic lines with the 7H(1)Lmar(7D) substitution type the differences in fertility manifestation were observed: most of the L-32(1) plants were sterile, in line L-32(2) only sporadic plants were sterile, and line L-32(3) was fertile. Simultaneously with these experiments, using self-pollinated progeny of the hybrids obtained in crosses of common wheat cultivar Saratovskaya 29 (2n = 41), monosomic for chromosome 7D, with common wheat cultivar Pyrotrix 28 with addition of pair of telocentric chromosomes 7H(1)Lmar(7D) of barley H. marinum subsp. gussoneanum, euplasmic wheat-barley ditelosomic substitution 7H(1)Lmar(7D) lines were isolated. The lines obtained had normal fertility. PCR analysis of the 18S/5S mitochondrial repeat (hereafter, mtDNA sequence) in alloplasmic and euplasmic ditelosomic substitution lines 7H(1)Lmar(7D) was performed. In the plants from alloplasmic sterile line L-32(1), the sequences only of the barley (maternal) type were revealed, while the plants from alloplasmic fertile lines L-32(2) and L-32(3) demonstrated heteroplasmy (the presence of barley- and wheat-like sequences within one individual). In euplasmic ditelosomic substitution lines the presence of only wheat-like 18S/5S mitochondrial repeat sequences was observed. The results indicate that the presence of barley-like mtDNA sequences in alloplasmic substitution lines was not associated with the presence of barley chromosomes in their nuclear genomes.

[Construction and molecular and cytogenetic analyses of euploid (2n = 42) and telocentric addition (2n = 42 + 2t) alloplasmic lines (Hordeum marinum subsp gussoneanum)-Triticum aestivum].

Individual plants from the BC1F5 and BC1F6 backcross progenies of barley--wheat (= H. geniculatum All.) (2n = 28) x T. aestivum L. (2n = 42)] and the BC1F6 progeny of their amphiploids were used to obtain alloplasmic euploid (2n = 42) lines L-28, L-29, and L-49 and alloplasmic telocentric addition (2n = 42 + 2t) lines L-37, L-38, and L-50. The lines were examined by genomic in situ hybridization (GISH), microsatellite analysis, chromosome C-banding, and PCR analysis of the mitochondrial 18S/5S repeat. Lines L-29 and L-49 were characterized by substitution of wild barley chromosome 7H1 for common wheat chromosome 7D. In line L-49, common wheat chromosomes 1B, 5D, and 7D were substituted with homeologous barley chromosomes. Lines L-37, L-38, and L-50 each contained a pair of telocentric chromosomes, which corresponded to barley chromosome arm 7H'L. All lines displayed heteroplasmy for the mitochondrial 18S/5S locus; i.e., both barley and wheat sequences were found.

[Features of the formation of self-fertile euploid lines (2n = 42) by self-pollination of the 46-chromosome barley-wheat BC1 hybrid Hordeum marinum subsp. gussoneanum Hudson (= H. geniculatum All.) (2n = 28) x Triticum aestivum L. (2n = 42)].

We studied some features of the development of self-fertile 42-chromosome lines on the base of self-pollination progeny of 46-chromosome plants obtained by backcrossing of barley--wheat hybrids Hordeum marinum subsp. gussoneanum Hudson (= H. geniculatum All.) (2n = 28) x Triticum aestivum L. (2n = 42). The stabilization of karyotypes, resulting in 42-chromosome plants of the wheat type was generally completed by generation BC1F10. The plants of all self-pollination progenies, including BC1F10, showed some phenotypic traits characteristic of wild barley. Plants of BC1F10 with the chromosome sets 2n = 42 and 2n = 42 + t were analyzed by RAPD with a set of 115 primers. Fragments of the wild barley genome were detected in RAPD patterns with 19 primers. Cross-hybridization confirmed that these fragments belonged to the wild barley genome. We raised four phenotypically different 42-chromosome lines from grains obtained from plants of generation BC1F10, and these lines proved to be cytogenetically stable and self-fertile when grown in the field.

[RAPD-based analysis of introgression of barley genetic material into the genome of alloplasmic wheat lines (Hordeum geniculatum All./ Triticum aestivum L.)]. / Izuchenie kharaktera introgressii geneticheskogo materiala iachmenia v genome alloplazmaticheskikh linii pshenitsy (Hordeum geniculatum All./ Triticum aestivum L.) s pomoshch'iu RAPD-analiza.

Genomes of three alloplasmic wheat lines obtained on the basis of barley--wheat hybrid Horderum geniculatum All. (2n = 28) x Triticum aestivum L. (2n = 42)(Pyrotrix 28) were examined using random amplified polymorphic DNA (RAPD) analysis. Line L-29 was obtained after first backcross of the initial hybrid with the wheat variety Pyrotrix 28 and ten subsequent self-pollinating generations. This line was represented by euploid plants with typical to the common wheat chromosome number (2n = 42), as well as by aneuploids, which contained an additional telocentric chromosome in the main karyotype (2n = 42 + t). Lines L-26 and L-27 were obtained by two backcrosses of one BC1 plant with the wheat variety Novosibirskaya 67 and one subsequent self-polination of one BC3 plant. Chromosome number in all these plants corresponded to 2n = 40 + 4t. RAPD analysis was carried out using seven primers, which were previously proved to be effective for identification of the barley genome fragments within hybrid genomes of alloplasmic lines. The presence of barley genome fragments in line L-29 was revealed by use of five primers, while in lines L-26 and L-27 these fragments were detected by use of one primer. The significant difference in the number of barley RAPD fragments in the genomes of alloplasmic lines obtained at different backcrossing stages suggests more intense displacement of barley genome during backcrossing compared to self-pollination in BC1 plants.