[Genealogical Analysis of the Use of Aegilops (Aegilops L.) Genetic Material in Wheat (Triticum Aestivum L.)].

A genealogical analysis of accessions in the global gene pool of the wheat database GRIS4.0 showed that the use of the genetic material of Aegilops in wheat breeding began about half a century ago. During this time, more than 1350 varieties and 9000 lines, the pedigree of which contains Aegilops species, were created in different regions of the world. The spatial and temporal dynamics of the distribution of wheat varieties containing the genetic material of Aegilops was investigated. Analysis of the data showed that most commercial varieties with a pedigree including Ae. tauschii and/or Ae. umbellulata were created and grown in North America. More than 70% of the varieties were produced with Ae. ventricosa, which is common in western and central Europe. A gradual increase in the proportion of varieties with Aegilops genetic material was recorded from 1962 to 2011. The percentage of varieties created with the involvement of Ae. umbellulata increased from 1-5% in the 1960s to 25-29% in the 2000s. Those created with Ae. tauschii increased from 0% to 14-18%, and those created with Ae. ventricosa increased from 1% to 34-37%. The increases in the number of these varieties indicates that the resistance genes from Aegilops species retain their effectiveness. Genealogical analysis of the varieties in which resistance genes from Aegilops were postulated revealed that varieties or lines that were sources of identified genes were often absent in the pedigree. This may be due to an incorrect pedigree record or errors in the identification of resistance genes by phytopathological testing and/or the use of molecular markers, or confusion in nurseries. Preliminary analysis of pedigrees provides an opportunity to reveal discrepancies between the pedigree and postulated genes.

[The effectiveness of molecular markers for the identification of Lr28, Lr35, and Lr47 genes in common wheat].

The effectiveness of molecular markers for the identification of leaf rust resistance genes Lr28, Lr35, Lr47 transferred to common wheat was assessed the using samplesof Triticum spp. and Aegilops spp. from Ae. speltoides. Markers Sr39F2/R3, BCD260F1/35R2 of gene Lr35 and PS10 of Lr47 gene were characterized by high efficiency and were revealed in a line of common wheat containing these genes, and samples of Ae. speltoides (their donor). Marker SCS421 of Lr28gene and markers Sr39#22r, Sr39#50s, BE500705 of Lr35/Sr39 genes turned out to be less specific. Marker SCS421 was amplified in the samples of the T. timopheevii species, and markers Sr39#22r, Sr39#50s--in the Ae. speltoides, Ae. tauschii, T. timopheevii, line KS90WRC010 (Lr41), the sort of common wheat In Memory of Maistrenko, obtained using synthetic hexaploid T. timopheevii x Ae. tauschii and introgressive lines obtained using Ae. speltoides. Marker BE500705, which indicates the absence of Lr35/Sr39 genes, was not revealed in 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, we showed a different distribution of Lr28 (77%), Lr35 (100%) and Lr47 (15%) genes in 13 studied samples ofAe. speltoides. In introgressive lines derived from Ae. speltoides, contemporary Russian sorts of common wheat and triticale variants Lr28, Lr35, Lr47 genes were not revealed.

16A system of molecular markers to identify alleles of the Rht-B1 and Rht-D1 genes controlling reduced height in bread wheat.

Mutant alleles of the Rht-B1 and Rht-D1 (Reduced height) genes are widely used in bread wheat breeding for the development of intensive-type cultivars. These genes and their f lanking regions have been sequenced and the point mutations leading to the nonsense codons (Rht-B1b, Rht-B1e, Rht-B1p and Rht-D1b alleles) and various insertions (Rht-B1c, Rht-B1h and Rht-B1i-1) associated with a change in plant height have been described. DNA-markers based on the allele-specif ic PCR have been developed to identify single-nucleotide changes. However, the use of such technique imposes stringent PCR conditions, and the resulting data are not always unambiguous. An alternative can be found in the CAPS technology: it detects differences in sequences by digesting PCR products. In the absence of restrictases capable of digesting DNA at the point mutation site, restriction sites can be introduced into the primer sequence (derived CAPS). The aim of this study was to propose a system of CAPS-, dCAPS- and STS-markers for identifying alleles of the reduced height genes frequently used in breeding programs. Three CAPS have been developed to identify the Rht-B1b, Rht-D1b, Rht-B1p alleles, as well as two dCAPS for Rht-B1b, Rht-B1e. STS-markers for the insertion-containing alleles Rht-B1c, Rht-B1h and Rht-B1i-1 have been selected from publications. The proposed markers were tested during the genotyping of 11 bread wheat accessions from the VIR collection with the abovementioned mutant alleles and the wild-type Rht-B1a and Rht-D1a. The presence of nonsense mutations was also conf irmed by the results of allele-specif ic PCR. This marker system, along with the existing ones, can be used to identify dwarf ing alleles of the Rht-B1 and Rht-D1 genes in bread wheat for genetic screening of accessions from ex situ collections and/or for marker-assisted selection.

[Global diversity of durum wheat Triticum durum desf. for alleles of gliadin-coding loci].

Genetic diversity for the alleles of gliadin-coding loci was studied with 465 durum wheat cultivars from 42 countries. A total of 108 alleles were identified for four loci; 60 alleles were described for the first time. Broad diversity of rare gliadin-coding alleles was observed. The highest genetic diversity was characteristic of durum wheat cultivars from the Middle East, Trans-Caucasia, the Pyrenean Peninsula, and the Balkans. Two genetically isolated ancient branches were isolated. A southern branch included mostly cultivars from the Mediterranean region, the Middle East, and Trans-Caucasia. A northern branch included Russian and Ukrainian durum wheat cultivars and varieties obtained on their basis. An additional group included durum wheat cultivars that had been obtained in several past decades on the basis of the material of international breeding centers (CIMMYT and ICARDA) and had low genetic diversity.

[Molecular markers in the genetic analysis of crossability of bread wheat with rye]. / Молекулярные маркеры в генетическом анализе скрещиваемости мягкой пшеницы с рожью.

Bread wheat (Triticum aestivum L.), the varieties of which are widely used for the grain production, is difficultly crossable with related species of Triticeae Dum. This factor limits the chance of introduction of alien genetic material into the wheat gene pool and the possibility of new varieties breeding with good adaptation to adverse environmental factors. The crossability between wheat and related species is controlled by Kr1-Kr4 genes (Crossability with Rye, Hordeum and Aegilops spp.) and the SKr gene (Suppressor of crossability). SKr and Kr1 have the largest influence on the trait. In the case of the recessive alleles, these genes do not function and the quantity of hybrid seeds after pollination with alien species can achieve more than 50 %. SKr is located on 5BS between the GBR0233 and Xgwm234 markers, closely linked with the markers Xcfb341, TGlc2 and gene12. Kr1 was mapped on 5BL, proximally to the Ph1 gene, between the EST-SSR markers Xw5145 and Xw9340. The markers of SKr were used to control the transfer of its recessive allele into other wheat genotypes, which made it possible to obtain highly crossable forms. However, the advantages of using the SKr and Kr1 markers in marker-assisted selection and in the screening of ex situ collections are not sufficiently studied. The published Kr1 sequence for varieties with different crossability offers great prospects, because it will be possible to create allele-specific markers. In this review, the following issues are considered: genetic resources created by wheat and rye hybridization, the geographical distribution of easy-to-cross forms of wheat, genetic control of the wheat and rye compatibility, advances of the use of molecular markers in the mapping of Kr-genes and their transmission control.

[Genetic differentiation of hexaploid wheat inferred from analysis of microsatellite loci].

Landraces of wheat can serve as important potential sources for extending the genetic basis of selection cultivars. Analysis of microsatellites and typing of polymorphism in a representative sample of 347 genotypes, including landraces and selection cultivars, was performed using a set of 38 selected oligonucleotide primer pairs. Classification of genotypes with respect to the level of their similarity was performed using cluster analysis. The data obtained pointed to genetic differentiation of hexaploid wheat. The groups of cultivars, the formation of which was thought to be associated with the main old areas of wheat cultivation in Europe and Asia, were identified. The basis of each of the groups was formed by landraces of common wheat. The differences between the groups identified were associated with multiple changes in the wheat genome and were expressed as quantitative differences in the allele frequencies of microsatellite loci. The results of the study are of interest in terms of understanding the structure of wheat genetic diversity and revealing the pathways of evolution of this culture.

[Diversity and the origin of the European population of Triticum dicoccum (Schrank) Schuebl. as revealed by chromosome analysis].

Cluster analysis of the Triticum dicoccum chromosome passports by artificial neural networks and UPGMA divided the European T. dicoccum population into two groups, West European and Volga-Balkan. The West European T. dicoccum accessions displayed a predominance of the marker translocation T7A:5B (67% of the accessions), which was also found in a few accessions from other countries (Turkey, Iran, and northern Africa), and were similar in chromosome C-banding patterns. The Volga-Balkan T. dicoccum accessions differed in the C-banding patterns of some chromosomes from the West European accessions, thus probably originating from another founder population. It was assumed that the T. dicoccum accessions carrying the T7A:5B translocation had a common origin and that the wild T. dicoccum population of the Middle East (Syria and Lebanon) contributed to the origin of West European T. dicoccum.

[Analysis of intraspecific divergence of hexaploid wheat Triticum spelta L. by chromosome C-banding]. / Analiz vnutrividovoi divergentsii geksaploidnoi pshenitsy Triticum spelta L. s pomoshch'iu metoda differentsial'nogo okrashivaniia khromosom.

Intraspecific divergence of hexaploid wheat Triticum spelta was studied by chromosome C-banding in 41 accessions of different geographic origins. The spelt accessions did not differ in karyotype structure or heterochromatin distribution from common wheat, but showed greater intraspecific polymorphism for chromosome rearrangements (translocations, inversions) and banding patterns. On evidence of C-banding patterns, spelt was assumed to occupy an intermediate position between tetraploid and hexaploid wheat species. Accessions of the Asian spelt subspecies had more diverse banding patterns than European accessions. A relatively high frequency of chromosome rearrangements was observed in Iranian accessions. Visual analysis revealed high uniformity of chromosome banding patterns in T. spelta populations of Afghanistan, Spain, and Germany (Bavarian group), suggesting a significant role of the founder effect in their evolution.

[Study of a collection of Triticum spelta L. wheat species using gliadin polymorphism]. / Issledovanie kollektsii vida pshenitsy Triticum spelta L. po polimorfizmu gliadinov.

Using gliadins, endosperm storage proteins of kernels, as markers, the genetic diversity of 170 samples from the Triticum spelta L. collection of the Vavilov Institute of Plant Industry was studied. High intraspecific polymorphism of the gliadin electrophoretic patterns was revealed. On the basis of similarity of the gliadin electrophoretic patterns, groups of samples were isolated, and the genetic structurization of the collection was performed.