Four genetically independent bread wheat lines with altered spike morphology caused by development of supernumerary spikelets at rachis nodes were characterized by modern methods of karyotype analysis, Cbanding and FISH. Three lines carried rearrangements of group 2 chromosomes: substitution of chromosome 2D and deletions of 2D, terminal and interstitial. The deletion breakpoints were defined by microsatellite analysis. The deletions were co-localized on the genetic map with the MRS1 gene, whose mutation caused the development of clusters of supernumerary spikelets at rachis nodes. Evaluations of spike phenotypes of the line with the supernumerary spikelet trait and Chinese Spring deletion lines carrying deletions of chromosomes 2A, 2B, and 2D demonstrated that deletion of a group 2 chromosome might alter spike morphology, resulting in development of supernumerary spikelets at rachis nodes and changes in spike length and density.

Four genetically independent bread wheat lines with altered spike morphology caused by development of supernumerary spikelets at rachis nodes were characterized by modern methods of karyotype analysis, Cbanding and FISH. Three lines carried rearrangements of group 2 chromosomes: substitution of chromosome 2D and deletions of 2D, terminal and interstitial. The deletion breakpoints were defined by microsatellite analysis. The deletions were co-localized on the genetic map with the MRS1 gene, whose mutation caused the development of clusters of supernumerary spikelets at rachis nodes. Evaluations of spike phenotypes of the line with the supernumerary spikelet trait and Chinese Spring deletion lines carrying deletions of chromosomes 2A, 2B, and 2D demonstrated that deletion of a group 2 chromosome might alter spike morphology, resulting in development of supernumerary spikelets at rachis nodes and changes in spike length and density.

Using C-banding and FISH methods, the karyotype of MC1611 induced mutant of bread wheat, which develop additional spikelets at a rachis node (trait “supernumerary spikelets”) was characterized. It was determined that the mutant phenotype is not associated with aneuploidy and major chromosomal rearrangements. The results of genetic analysis showed that supernumerary spikelets of the line are caused by a mutation of the single Bh-D.1 gene, influenced by the genetic background. The mutation causes abnormalities of inflorescence morphogenesis associated with the development of ectopic spikelet meristems in place of floral meristems in the basal part of the spikelets, causing the appearance of additional spikes at a rachis node. The mutant phenotype suggests that the Bh-D gene determines the fate of the lateral meristems in ear, which develops as floral meristem and gives rise to floral organs in wild-type inflorescences. In the bh-D.1 mutant, the floral meristem identity is impaired. The characterized mutant can be used in further studies on molecular genetic basis of development of wheat inflorescence.

С помощью методов С-окрашивания и FISH охарактеризован кариотип индуцированного мутанта MC1611 мягкой пшеницы, у которого развиваются дополнительные колоски с уступах колосового стержня (признак “многоколосковость”). Обнаружено, что мутантный фенотип не связан с анеуплоидией и крупными хромосомными перестройками. Результаты генетического анализа показали, что многоколосковость линии обусловлена мутацией одного гена, обозначенного bh-D.1, на действие которого оказывает влияние генотипическая среда. Мутация вызывает аномалии морфогенеза соцветия, связанные с развитием эктопических колосковых меристем на месте флоральных меристем в базальной части колоска, что приводит к появлению дополнительных колосков в уступе колосового стержня. Мутантный фенотип предполагает, что ген Bh-D определяет судьбу латеральных меристем в колоске, которые у соцветий дикого типа развиваются как флоральные и дают начало органам цветка. У мутанта bh-D.1 нарушено установление идентичности флоральных меристем. Охарактеризованный мутант может быть использован в дальнейших исследованиях по изучению молекулярно-генетических основ развития соцветия пшеницы.

The effectiveness of molecular markers for the identification of leaf rust resistance genes Lr28, Lr35 and Lr47 transferred to common wheat from Ae. speltoides was assessed using samples of Triticum spp. and Aegilops spp. The markers Sr39F2/R3, BCD260F1/35R2 of the gene Lr35 and PS10 of the Lr47 gene were characterized by high efficiency and were revealed in the lines of common wheat containing these genes, and samples of Ae. speltoides species, the donor of these genes. The marker SCS421 of the Lr28 gene and the markers Sr39#22r, Sr39#50s, BE500705 of the Lr35/Sr39 genes turned out to be less specific. The marker SCS421 was amplified in the samples of the T. timopheevii species, line KS90WRC010 (Lr41), the cultivar of common wheat Pamyati Maystrenko, obtained using synthetic hexaploid T. timopheevii × Ae. tauschii and introgressive lines obtained using Ae. speltoides. The marker BE500705, which indicates the absence of the Lr35/Sr39 genes, was not revealed in the lines TcLr35 and MqSr39, in Ae. speltoides, Ae. tauschii and T. boeoticum (kk-61034, 61038). Analysis of the nucleotide sequences of amplification products obtained with the markers SCS421 and Sr39#22r indicated their low homology with TcLr28 and TcLr35. Using molecular markers, a different distribution of the Lr28 (77%), Lr35 (100%) and Lr47 (15%) genes in 13 studied samples of Ae. speltoides was shown. In introgressive lines derived from Ae. speltoides, contemporary Russian cultivars of common wheat and triticale the Lr28, Lr35, Lr47 genes were not revealed.

Synthetic hexaploids are bridges for transferring new genes that determine resistance to stress factors from wild-type species to bread wheat. In the present work, the method of developing the spring bread wheat variety Pamyati Maystrenko and the results of its study are described. This variety was obtained using one of the immune lines produced earlier via the hybridization of the spring bread wheat variety Saratovskaya 29 with the synthetic hexaploid T. timopheevii Zhuk. x Ae. tauschii Coss. The C-staining of chromosomes in the Pamyati Maystrenko variety revealed substitutions of 2B and 6B chromosomes by the homeologous chromosomes of the G genome of T. timopheevii and the substitution of chromosome 1D by an orthologous chromosome ofAe. tauschii. It was found that this variety is characterized by resistance to leaf and stem rust, powdery mildew, and loose smut as well as by high grain and bread-making qualities. The role of the alien genetic material introgressed into the bread-wheat genome in the expression of adaptive and economically valuable traits in the Pamyati Maystrenko variety is discussed.

Синтетические гексаплоиды являются “мостами” для передачи новых генов, определяющих устойчивость к стрессовым факторам, от дикорастущих видов мягкой пшенице. В настоящей работе описаны метод создания и результаты исследования сорта яровой мягкой пшеницы “Памяти Майстренко”, полученного с использованием одной из иммунных линий, созданных ранее в результате гибридизации сорта яровой мягкой пшеницы Саратовская 29 с синтетическим гексаплоидом T. timopheevii Zhuk. ? Ae. tauschii Coss. С помощью методов С-окрашивания хромосом у сорта “Памяти Майстренко” выявлены замещения хромосом 2В и 6В на гомеологичные хромосомы G-генома T. timopheevii и замещение хромосомы 1D на ортологичную хромосому Ae. tauschii. Показано, что этот сорт характеризуется устойчивостью к бурой и стеблевой ржавчине, мучнистой росе и пыльной головне, а также высокими показателями качества зерна и хлебопекарных свойств. Обсуждается роль чужеродного генетического материала, интрогрессированного в геном мягкой пшеницы, в проявлении адаптивных и хозяйственно-ценных признаков у созданного сорта.

Synthetic hexaploids are bridges for transferring new genes that determine resistance to stress factors from wild-type species to bread wheat. In the present work, the method of developing the spring bread wheat variety Pamyati Maystrenko and the results of its study are described. This variety was obtained using one of the immune lines produced earlier via the hybridization of the spring bread wheat variety Saratovskaya 29 with the synthetic hexaploid T. timopheevii Zhuk. × Ae. tauschii Coss. The C-staining of chromosomes in the Pamyati Maystrenko variety revealed substitutions of 2B and 6B chromosomes by the homeologous chromosomes of the G genome of T. timopheevii and the substitution of chromosome 1D by an orthologous chromosome of Ae. tauschii. It was found that this variety is characterized by resistance to leaf and stem rust, powdery mildew, and loose smut as well as by high grain and bread-making qualities. The role of the alien genetic material introgressed into the bread-wheat genome in the expression of adaptive and economically valuable traits in the Pamyati Maystrenko variety is discussed.

Little is known about the relationship between compact spike loci in hexaploid wheat species. We studied two new compact spike mutants of common wheat Triticum aestivum L. (2n = 6x = 42, genome formula BBAADD). The new compact spike genes, C 739 of MCK 739 and Cp of near-isogenic line Mironovskaya 808 (Vrn1), were mapped using aneuploid stocks and microsatellite markers. The C 739 and Cp loci were distally linked with the microsatellite marker Xbarc319 in the F2 populations of MCK 739 × ‘Novosibirskaya 67’ and Cp-Mironovskaya 808 (Vrn1) × ‘Saratovskaya 29’. It was evident that the loci affecting compact spikes in T. aestivum mutants were located on chromosome 5AL distal from Q locus. These loci also affected to semi-dwarfism. We named this locus Cp1 (C ompact p lant 1) for all accessions. Cp1 was allelic to C 17648 gene located on the chromosome 5AL of tetraploid wheat [Triticum durum Desf. (2n = 4x = 28, genome formula BBAA)]. These dominant genes on chromosome 5AL will be utilized as new gene resources of compact spike morphology in hexaploid wheat. Relationship between loci Q and Cp1 was also discussed.

Изучали шесть почти изогенных линий сорта Саратовская 29 по пяти генам-маркерам, относящимся к различным видам – Triticum compactum L., T. polonicum L., T. petropavlovskyi Udacz. et Migusch., Aegilops elongatum Host. и Secale cereale L. Показано, что у почти изогенных линий мягкой пшеницы сорта Саратовская 29 введенные гены-маркеры, имеющие таксономическое значение (гены С и Р), обладают высокими плейотропными эффектами на признаки продуктивности колоса.

Six near-isogenic lines of the wheat cultivar Saratovskaya 29 carrying five marker genes from different species (Triticum compactum L., T. polonicum L., T. petropavlovskyi Udacz. et Migusch., Aegilops elongatum Host. and Secale cereale L.) were studied. It was shown that the introduced marker genes of taxonomic significance, C and P, have strong pleiotropic effects on quantitative traits of the spike productivity.

Storage proteins (prolamines, puroindolines, and Waxy) were studied in common wheat introgression lines obtained with the use of the Saratovskaya 29 (S29) cultivar line and synthetic hexaploid wheat (Triticum timopheevii Zhuk. × T. tauschii) (Sintetik, Sin.) displaying complex resistance to fungal infections. Comparative analysis of storage proteins in the introgression lines of common wheat Triticum aestivum L. and in the parental forms revealed the only line (BC5) having a substitution at the Gli-B2 locus from Sintetik. Hybrid lines subjected to nine backcrosses with the recurrent parental form S29 and selections for resistance to pathogens can be considered as nearly isogenic for the selected trait and retaining the allelic composition of (1) prolamines responsible for the bread-making qualitiy, (2) puroindolines associated with grain texture, and (3) Waxy proteins responsible for nutritive qualities. These lines are valuable as donors of immunity in breeding programs without the loss of the quality of flour and grain as compared to the S29 line and are also important in searching for genes determining resistance to leaf and stem rust and to powdery mildew. The amphiploid has a number of characters (silent Glu-A1 locus and Ha genotype) that can negatively affect the quality of flour and grain and thus should be taken into account when choosing this donor.

Advanced backcross QTL analysis was used to identify QTLs for seedling and adult plant resistance to leaf rust in introgression lines derived from a cross between the spring wheat cultivar 'Saratovskaya 29' and a synthetic allopolyploid wheat (T. timopheevii/T. tauschii). F-2 mapping populations involving two backcross selections ('BC5' and 'BC9' lines) were genotyped with microsatellite markers. Two significant QTL for adult plant resistance were identified in line 'BC5': one on chromosome 2B, but originating from chromosome 2G, explained 31% of the trait variance. The other, derived from T. tauschii and mapped to the short arm of chromosome 2D explained 19% of the trait variance. In the second line, one major seedling and adult plant resistance QTL was identified on chromosome 2B. Both QTL co-located to the same marker interval. Such introgression lines, resulting from the reconstruction of common wheat genome, are of interest both as initial material for breeding and improvement of current cultivars, and as a resource for the study of the interaction and transformation of genomes.

Two monosomic alien substitution lines (MAS lines, 2n=41=40+5R) of wheat Triticum aestivum L. cv. ‘Saratovskaya 29’ were used as recipients in the development of inter-varietal substitution lines for chromosomes 5A and 5D. In the MAS lines, chromosomes 5A or 5D of ‘Saratovskaya 29’ were replaced by homoeologous univalent chromosome 5R of rye Secale cereale L. cv. ‘Onokhoiskaya’, which bears the Hp marker gene coding for hairy peduncle. The donors included 18 spring and winter wheat varieties. The MAS lines were developed by crossing monosomic lines of ‘Saratovskaya 29’ for chromosomes 5A and 5D to a wheat-rye substitution line of ‘Saratovskaya 29’ 5R(5D) followed by cytological and morphological selection of plants with chromosome configuration 20II +5RI in metaphase I of pollen mother cells from F 1 and F 2 plants with slightly hairy peduncles. It was shown that MAS lines could be maintained during long-term propagation (18 generations). Use of MAS lines with the Hp marker gene allows acceleration and abbreviation of cytological analysis and elimination of the probability of ‘univalent switch’ in the course of the development of substitution lines. The method was applied to the development of 22 ‘Saratovskaya 29’ lines with inter-varietal substitution for chromosomes 5A and 5D. Fourteen and thirteen microsatellite markers located in chromosomes 5A and 5D, respectively, were used to prove the authenticity of the inter-varietal substitution lines. According to these markers, 21 substitution lines from 22 studied were correct.

Anthocyanin pigmentation of various organs develops during plant ontogeny in response to adverse and damaging abiotic and biotic stressors (environmental factors). Using the monosome method, the genes responsible for anther and culm anthocyanin pigmentation (Pan1 and Pc2, respectively) were localized to 7D chromosome in introgressive lines from crosses between common wheat Triticum aestivum L. and the species Triticum timopheevii Zhuk. Genetic analysis of ten common wheat genotypes using testers carrying genes Pan1, Pc1 and Pc2 showed that these genotypes contained Pan1 and Pc2 genes. Visual examination of plants from 70 and 76 varieties of respectively winter and spring common wheat revealed anthocyanin pigmentation of anthers and culms in 36 varieties. Pan1 and Pc2 genes were presumably introduced into common wheat from Aegilops tauschii (Eig.) Tzvel., a donor of the D genome.

The progeny of BC 6 F 2–4 –BC 9 F 2–4 has been analyzed for resistance to brown rust ( Lr genes) and powdery mildew ( Pm genes). This progeny was obtained due to introgression of the alien material from the synthetic hexaploid wheat Triticum timopheevii / Aegilops squarrosa (= Triticum tauschiia AGGDD, 2 n = 42) into the common wheat variety Saratovskaya 29. Against the background of natural infection, the lines resistant to both diseases and to either of them were developed. The brown-rust and powdery-mildew resistance is controlled by one/two effective independent genes Lr and Pm .

The results of genetic studies of common wheat that have been conducted in Novosibirsk, Russia, over the past 20 years by a research team are summarized. The research strategy was to develop a collection of aneuploids and substitution lines to be further used for chromosomal localization of genes and in the study of the genetic variability of wheat. On the basis of two cultivars, namely Saratovskaya 29 and Diamant, we have developed 6 sets of aneuploids with a complete set of monosomic lines for each, plus sets of lines ditelosomic and monotelosomic for “standard” arms. Exploiting the monotelosomics, 108 single chromosome intervarietal substitutions, 13 lines with alien substitutions (mono- and disomics) and 11 addition lines have been developed. A collection of lines isogenic for dominant marker genes of morphological characters has also been developed. The genetic collection was used in chromosomal localization of 15 genes, for many of which chromosome arms have been determined. Positively or negatively, the question of allelism within some loci has been answered.

The growth habit, ear emergence time, and frost tolerance of wheat/rye substitution lines have been studied in cultivars Rang and Mironovskaya Krupnozernaya whose chromosome 5A is substituted with chromosome 5R of Onkhoyskaya rye. Hybrid analysis has demonstrated that the spring habit of the recipient cultivars Rang and Mironovskaya Krupnozernaya is controlled by dominant gene Vrn-A1 located in chromosome 5A. Onokhoyskaya rye has a dominant gene for the spring habit ( Sp1 ) located in chromosome 5R. It has been found that the resultant 5R(5A) alien-substitution lines have a winter type of development and ears do not emerge during summer in plants sown in spring. The change in growth habit has been shown to be related to the absence of the rye Sp1 gene expression in the substitution lines. The winter hardiness of winter 5R(5A) alien-substitution lines has been studied under the environmental conditions of Novosibirsk. Testing the lines in the first winter demonstrated that their winter survival is 20–27%. The possible presence of the frost resistance gene homeoallelic to the known genes Fr1 and Fr2 of the common wheat located on chromosomes 5A and 5D, respectively, is discussed.

Immune lines resistant both to leaf rust and to powdery mildew were constructed on the basis of common wheat cultivar Saratovskaya 29. Synthetic wheat Triticum timopheevii/Aegilops squarrosa (AAGGDD, 2 n = 42) of Savov (Bulgaria) was used as a source of resistance genes. Using cytological analysis of BC 2 , we selected resistant plants (21") free from meiosis 1 (M1) defects. With these plants and continuous selection, BC 8 –BC 9 immune lines were obtained. The lines were shown to carry new resistance genes differing from the known ones, and were proposed as donors of immunity to the diseases.