Triticale introgressive lines were developed by incorporating diploid wheat (Triticum monococcum [TM16]) genes into the hexaploid triticale genotype LT522/6. The synthetic allotetraploid T. monococcum cereale (AmAmRR) was used as a bridging form to introduce the genes. A group of 43 introgressive lines, parental stocks and a check cultivar were inoculated at the seedling stage (in the greenhouse) and at the adult plant stage (in the field) with four pathotypes of Puccinia striiformis f. sp. tritici to determine if the stripe rust resistance was derived from TM16 and to analyze the expression of the diploid wheat gene(s) at the hexaploid level. At the seedling stage, 14 triticale introgressive lines expressed resistance to some of the used pathotypes, showing introduction of a genetic material from the T. monococcum genome. Among them, 7 lines were resistant to all four stripe rust pathotypes applied at this stage. In the field, adult plant resistance and percentage of infected leaf area were scored and transformed into the coefficient of infection. Plant response to stripe rust was compatible at these two developmental stages with a high statistical probability showing the genetic dependence on the same genetic background. Also observed was a full concordance of the adult plant resistance to stripe rust with previously assessed resistance to leaf rust, as well as the highly significant linkage of the resistance to the both diseases at the seedling stage in the set of the tested introgression lines. This result strongly suggests that T. monococcum genes responsible for these characters are located in proximity.
Wild related species are a useful reservoir of valuable genes for widening the genetic base of wheat and for the reduction of the vulnerability of wheat cultivars to pathogens, fungal diseases and environmental hazards. In this work, the action of prezygotic and postzygotic incrossability barriers was characterized, determining the possibilities of direct introduction of Am - genome from Triticum monococcum and D-genome from Triticum. tauschii into T. aestivum cultivars, with elimination of commonly performed bridging hybridisation with tetraploid wheat. As gene recipient parents, Polish cultivars of hexaploid wheat cv. Omega, cv. Igna (spring) and cv. Tercja (winter) were used. Application of wheat cultivars as female parents in hybridisation with T. tauschii yielded a very low percentage of effective pollination (0-1.2%). In reciprocal crosses prezygotic incompatibility barriers were more weakly expressed, and percentages of effective pollination (i.e. pollination which initiates the first steps of seed development) were from 28.3 to 32.4. The ability to form callus on MS medium with standard for areals concentration of growth regulators (i.e. 1 mg dcm-3 IAA and 1.0 mg dcm-3 kinetine) was positively correlated with F1 plants regeneration rate. Introduction of Am - genome into common wheat cultivars can be performed exclusively using T. monococcum as a male parent because of pollen sterility caused by T. monococcum cytoplasm in hybrid progeny. After pollination of T. aestivum stigmas with pollen of T. monococcum the frequency of effective pollination was 1.2-4.9%. The most important factor influencing the results of in vitro culture was the lethality of young seedlings, caused by postzygotic gene incompatibility.
Macrophages (Mf) play an important role in induction and regulation of the immune response. It was shown previously that subcutaneous injection of hapten conjugated macrophages (TNP-Mf) induces the contact hypersensitivity (CHS) response, whereas intravenous (i.v.) or intraperitioneal administration of TNP-Mf results in unresponsiveness as a result of induced T suppressor (Ts) cells. The aim of this study was to determine if different T cell populations influence macrophages to become inducers of immunological suppression. Our findings show that indeed i.v. injection of TNP labeled macrophages isolated from control mice into syngenic recipients induces unresponsiveness. However, i.v. administration of TNP substituted macrophages isolated from TCR'-/-, TCR*-/- and $2m-/- mice induces strong CHS similar to that observed after skin painting with TNP-Cl.Moreover, it was shown that TNP conjugated macrophages isolated from CD1d-/- mice were still able to promote immunosuppression when injected intravenously. This suggests that TCR'$+ CD8+ and TCR(*+ lymphocytes stimulate macrophages to induce immunosuppression instead of a strong CHS reaction, whereas CD1d dependent NKT cells are not involved in negative regulation of macrophage function.
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