Northern Kazakhstan and Western Siberia of Russia represent a relatively uniform continuous area of spring wheat cultivation of ~20 million ha. Despite the dry climate, cultivation of susceptible varieties resulted in epidemics of leaf rust on average in 1 year out of 4, affecting up to 5 million ha with yield losses of up to 25–30%. The leaf rust population showed absence of virulence for genes Lr9 and Lr24 and low frequency of isolates with virulence to Lr11, Lr16, Lr18, and Lr28. The field observations indicated that genes Lr28 and Lr36 provide resistance. All the wheat cultivars are susceptible to leaf rust and only recently have several resistant lines and new varieties have been tested in trials. The current resistance breeding efforts are based on incorporation of the resistance from local and foreign sources. The breeding strategy is not based on detailed knowledge of the leaf rust population and its interaction with the host because of limited pathology and genetics research capacity. However, practical breeding efforts in combining proven resistance with adaptation traits resulted in the development of new competitive resistant germplasm. Shuttle breeding between the region and CIMMYT-Mexico to enhance resistance contributes to regional efforts.

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Androgenic ability was studied in anther cultures of euplasmic lines of common wheat and allo plasmic recombinant lines (H. vulgare)-T. aestivum with 1RS.1BL and 7DL 7Ai translocations. The ability to produce androgenic structures and plantlet regeneration are suppressed in lines carrying both transloca tions. Alloplasmic recombinant lines (H. vulgare)-T. aestivum with the 1RS.1BL and 7DL 7Ai transloca tions, as well as alloplasmic lines with the 1RS.1BL translocation, are characterized by their increased ability to form androgenic structures, including polyembryos, and plantlet regeneration compared to euplasmic lines. The inducing reciprocal influence of barley cytoplasm and rye chromosome 1RS on the androgenesis abil ity of lines (H. vulgare)-T. aestivum with 1RS.1BL and 7DL 7Ai translocations is discussed. Double haploid lines were developed from androgenic plants with spontaneously doubled chromosome numbers and restored fertility. Of the lines carrying the translocations, the most promising with regard to the exhibition of agronomic valuable traits and resistance to diseases were selected in order to utilize them in breeding programs.

Alloplasmic lines are formed when the cytoplasm of one species is replaced by the cytoplasm of another as a result of repeated recurrent crosses of wide hybrids with the paternal genotype. Since the cytoplasm replacement results in new intergenomic interactions between a nucleus and cytoplasm leading to variability of plant characteristics, alloplasmic lines with restored fertility can be an additional source of biodiversity of cultivated plants. Earlier, recombinant alloplasmic lines (H. vulgare)-T. aestivumdesignated as L-17(1)–L-17(37) were formed from a plant with partially restored fertility of the BC3 generation of barley-wheat hybridH. vulgare(cv. Nepolegayushchii) ×T. aestivum(cv. Saratovskaya 29). This male-sterile hybrid was consistently backcrossed with wheat varieties Mironovskaya 808 (twice) and Saratovskaya 29, and Mironovskaya 808 had a positive impact on the restoration of fertility. This paper presents the results of investigation into a group of recombinant alloplasmic lines (L-17F4), as well as into doubled haploids (DH) lines – alloplasmic DH-17-lines obtained from anther culture of alloplasmic lines (L-17F2). The most productive of these lines were used as initial breeding genotypes. Hybrid form Lutescens 311/00-22 developed from the crossing of the alloplasmic DH(1)-17 line (as maternal genotype) with euplasmic line Com37 (CIMMYT), the source of the 1RS.1BL wheat-rye translocation, proved to be successful for breeding. The presence of the 1RS.1BL translocation in the genome of the Lutescens 311/00-22 form and the L-311(1)–L-311(6) alloplasmic lines isolated from it did not lead to a decrease of fertility or sterility in the plants. This indicates that the chromosome of the 1BS wheat does not carry the gene(s) that determine the restoration of fertility in the studied (H. vulgare)-T. aestivumalloplasmic lines. Alloplasmic lines L-311(1)–L-311(6) showed their advantage in comparison with the standard varieties for resistance to leaf and stem rust, yield, and grain quality. The breeding tests performed at Omsk Agricultural Scientific Center, Agrocomplex “Kurgansemena”, Federal State Unitary Enterprise “Ishimskoe” (Tyumen Region), using alloplasmic lines L-311(5), L-311(4) and L-311(6) resulted in varieties of spring common wheat Sigma, Uralosibirskaya 2 and Ishimskaya 11, respectively.

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