Introgression of common wheat lines with genetic material of Agropyron glaucum

Grey wheatgrass Agropyron glaucum (Desf. ex DC) Roem. & Schult is a valuable source of genes for resistance to diseases, frost resistance, and salt tolerance. An unstable 76-chromosomal amphidiploid combining genomes A and B of common wheat variety Avrora, six chromosomes of genome D of the same variety, and a full set of Ag. glaucum (2n = 42) chromosomes was used as an intermediate to transfer the genetic material from the wild donor to the said wheat variety. A large set of wheat introgression lines differing in a variety of morphobiological characters was developed. For effective employment of the developed lines in breeding, cytological and molecular-genetical analyses of the lines were conducted, and their pest resistance and grain technological properties were evaluated. We report the investigation of 25 common wheat introgression lines with genetic material from Ag. glaucum, not studied hitherto. All lines but D43 formed 21 bivalents in МI meiosis. In lines D3, D21, and D23, the genetic material of Ag. glaucum was present as a translocation segment. Lines D7, D43, and D49 carried substituted chromosomes and, presumably, translocations. One pair of wheat chromosomes was substituted in 18 lines. For the identification of translocations and substituted chromosomes, microsatellite analysis was done with markers specific to D genome chromosomes. The introgression touched all D genome chromosomes except 3D and 4D. The lines under the study differed in protein and gluten contents, gluten quality, and bread-making quality. Study of gliadin spectra revealed changes in the gliadin formula in 7 of 12 lines with reference to the recipient Avrora variety. Thus, the results obtained point to genetic diversity of investigated introgression lines and their value for common wheat breeding

STUDY OF INTROGRESSIVE LINES OF COMMON WHEAT WITH Aegilops tauschii GENETIC MATERIAL FOR RESISTANCE TO LEAF RUST

The synthetic forms of Triticum miguschovae (GGAADD), Triticum palmovae (AbAbDD), T. durum (M. it.)/Ae. Tauschii (BBAADD) and the introgressive lines of common wheat created on their basis were evaluated for resistance to leaf rust. All synthetic forms have a high resis­tance to leaf rust. Twenty-two lines of common wheatresistant to leaf rust with genetic material from T. miguschovae, 10 lines with genetic material from T. du­rum (M. it.)/Ae. tauschii and 4 lines obtained on the basis of T. palmovae were identified. A screening with the use of molecular markers for the presence of leaf rust resistance genes Lr21, Lr26, Lr32, Lr39 was done. The GDM35 marker linked to the Lr39 gene was identified in the synthetic forms. Molecular markers Lr21F/R and BARC135 linked to the genes Lr21 and Lr32, respectively, were not identified. Resistance to leaf rust in lines 729, 1555, 2203, 2289, 2295, 2296, 4155, 4171, obtained on the basis of T. miguschovae, lines 3261, 3265, obtained on the basis of T. palmovae, and in line 4141 with the genetic material from T. durum (M. it.)/Ae. Tauschii is controlled by the presence of the Lr39 gene. The SCM9 marker indicating the presence of translocation of 1BL.1RS with the Lr26 gene was detected in 15 lines obtained on the basis of T. miguschovae, in 2 lines with genetic material from T. durum (M. it.)/Ae. tauschii, and in 1 line created on the basis of T. palmovae. Lines 729, 1555, 2203, 2289, 2295, 2296, 4155, 4171 obtained with the participation of T. miguschovae and line 3261 with the participation of T. palmovae carry a combination of genes (Lr39+Lr26)

Using the synthetic form RS5 to obtain new introgressive lines of common wheat

The use of the gene pool of wild relatives, which have a significant reserve of genetic diversity, is of immediate interest for breeding common wheat. The creation and use of synthetic forms as “bridges” is an effective method of transferring valuable genetic material from wild relatives to cultivated wheat. For this purpose, genome addition, genome substitution and recombinant “secondary” synthetic forms have been created in the P.P. Lukyanenko National Center of Grain. The synthetic recombination form RS5 (BBAASDt ), in which the third genome consists of chromosomes of Aegilops speltoides (S) and Aegilops tauschii (Dt ), was obtained from crossing the synthetic forms Avrodes (BBAASS) and M.it./Ae. tauschii (BBAADt Dt ), in which the D genome from Ae. tauschii was added to the BBAA genomes of the durum wheat cultivar Mutico italicum. Introgression lines resistant to leaf rust, yellow rust and powdery mildew have been obtained from backcrosses with the susceptible common wheat cultivars Krasnodarskaya 99, Rostislav and Zhirovka. Twelve resistant lines that additionally have high technological characteristics of grain and flour have been selected. The cytological study (С-banding) has revealed chromosomal modifications in 6 of 8 lines under study. The rearrangements mainly affected the chromosomes of the D genome, 1D, 3D, 4D, 6D and 7D. It was found that in most cases the genetic material from the synthetic form RS5 in the studied lines was represented by substituted chromosomes from Ae. tauschii. In line 5791p17, the substitution of chromosomes 6D from Ae. tauschii and 7D from Ae. speltoides was revealed. Substitutions 4D(4Dt ), 6D(6Dt ) from Ae. tauschii and 7D(7S) from Ae. speltoides were obtained for the first time. Molecular analysis of 12 lines did not reveal effective leaf rust resistance genes, presumably present in synthetic forms of M.it./Ae. tauschii and Avrodes. It is assumed that the lines may carry previously unidentified genes for fungal disease resistance, in particular for resistance to leaf rust, from Ae. tauschii and Ae. speltoides

Use of a synthetic form Avrodes for transfer of leaf rust resistance from Aegilops speltoides to common wheat

Diploid wild relative of wheat – Aegilops speltoides – is a valuable source of genes for resistance to diseases. The synthetic form Avrodes (BBAASS) was used as a bridge to transfer leaf rust resistance genes from Ae. speltoides to common wheat. Introgression lines obtained from crosses of Avrodes and susceptible common wheat cultivars were evaluated in a field leaf rust nursery. Resistance levels varied from high to moderate. Testing of lines with the use of molecular markers has shown that some lines have the Lr28 and Lr35 genes inherited from synthetic form Avrodes. The majority of resistance lines have not been found to carry these genes. The Lr47 and Lr51 genes were not identified in the Avrodes and introgression lines. The analysis of chromosome pairing in F1 hybrids showed that the transfer of a genetic material from Avrodes to common wheat basically occurs through translocations. Lines with translocations on chromosomes 2D and 5D were identified by C-banding and FISH. The translocations differed in chromosomal location from known leaf resistance genes transferred to common wheat from Ae. speltoides. Hence it was assumed that new genes were introduced into the common wheat genome from Ae. speltoides. Introgression lines have been studied for productivity and technological qualities of grain. Lines AA60n9 and D37n10 combine high resistance to leaf rust with good characteristics of productivity and technological qualities of grain. The received results demonstrate a genetic diversity and a value of the investigated introgression lines for breeding of common wheat

USE OF SYNTHETIC FORMS IN THE PRESERVATION AND EXPLOITATION OF THE GENE POOL OF WILD COMMON WHEAT RELATIVES

The results of investigation and exploitation of the synthetic genome addition line T. miguschovae (Triticum militinae /Aegilops tauschii) and genome substitution lines Avrodes, Avrosis, Avrolata, Avrotata, Avroale, and Avrocum are reported. In the genome substitution forms, genomes of Ae. speltoides, Ae. sharonensis, Ae. umbellulata, Ae. uniaristata, Secale cereale and Agropyron glaucum are substituted for the D-genome of common wheat cultivar Avrora. The synthetic forms provide a unique genetic basis for preservation and use of the gene pool of wild relatives in wheat breeding. These forms have been used to produce secondary recombination synthetic forms (RS forms) with genome constitutions BBAADS, BBAASR and BBAASSsh. These cytologically stable introgression lines combine disease resistance and high protein content. Five common winter wheat cultivars have been developed on the base of the introgression lines obtained