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- Author or Editor: M. Megyeri x
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In recent years 56 accessions of Triticum timopheevii Zhuk. (2n=4x=28, AtAtGG) were characterized for the main phenotypic and resistance characters. Among these accessions 38 originated from the base species together with subspecies and varietas forms thereof, and 18 belong to the subspecies armeniacum group. After the evaluation of field assessment data gathered over 12 years, the most promising 11 accessions were selected for a crossability trial with cultivated einkorn. As a result of this trial, the accession with the highest seed set (Acc. No.: MVGB845) was chosen for the development of a new synthetic amphiploid using the same semi-dwarf line of diploid cultivated einkorn (Triticum monococcum L. ssp. monococcum 1T-1, 2n=2x=14, AmAm) as in the crossability trial. This einkorn line was bred in Martonvásár, and has both outstanding resistance and other promising phenotypic and agronomic characters.After crossing the accession MVGB845 with 1T-1, the triploid hybrids were treated with colchicine to obtain fertile progenies with a doubled genome. The newly developed synthetic hexaploid wheat breeding stock (named Triticum timococcum Kost., 2n=6x=42, AtAtGGAmAm) could ease the introgression of valuable resistance genes into bread wheat at the hexaploid level (bridge-crossing).The aim of the present research was to redevelop Triticum timococcum based on a detailed characterization of gene bank accessions, and to introduce this new material into wheat breeding.
Cultivated einkorn (Triticum monococcum L. ssp. monococcum) is an excellent source of resistance against several wheat diseases and quality parameters. Semi-dwarf einkorn lines with good crossability were identified in order to produce Triticum turgidum × T. monococcum synthetic amphiploids. Two combinations were used to develop the amphiploids: durum × einkorn and emmer × einkorn.After the genome duplication of F1 seeds, highly fertile amphiploids were developed. The AuBAm genome structure of the progenies was confirmed by genomic in situ hybridization (GISH).Lines derived from durum × einkorn and emmer × einkorn crosses were studied for agronomic performance, disease resistance and genetic variability. Both amphiploid combinations showed excellent resistance against certain wheat diseases (leaf rust, powdery mildew), but not against fusarium. The durum-based synthetic amphiploid lines showed a higher level of phenotypic diversity. The newly produced T. turgidum × T. monococcum synthetic hexaploids are promising genetic resources for wheat breeding. Selected durum × einkorn lines are currently used in bread wheat improvement to transfer the useful properties of einkorn into cultivated hexaploid wheat via ‘bridge-crossing’.
Genebanks are storage facilities designed to maintain the plant genetic resources of crop varieties (and their wild relatives) and to ensure that they are made available and distributed for use by plant breeders, researchers and farmers. The Martonvásár Cereal Genebank (MV-CGB) collection evolved from the working collections of local breeders and consists predominantly of local and regional materials. Established in 1992 by the Agricultural Research Institute of the Hungarian Academy of Sciences (Bedő, 2009), MVCGB with its over 10,000 accessions of the major species (Triticum, Aegilops, Agropyron, Elymus, Thinopyrum, Pseudoroegneria, Secale, Hordeum, Avena, Zea mays), became one of the approx. 80 cereal germplasm collections that exist globally. In Martonvásár breeding is underway on a number of cereal species, and large numbers of genotypes are tested each year in the field and under laboratory conditions. The increasing size of the research programmes assisted by a modern genebank background involve an enormous increase in the quantity of data that must be handled during research activities such as traditional breeding, pre-breeding and organic breeding. A computerized system is of primary importance to synchronize breeding and genebank activities, to monitor the quality and quantity of seed accessions in cold storage, to assist the registration of samples, and to facilitate characterization, regeneration and germplasm distribution.
Triticum monococcum represents an important source of useful genes and alleles that it would be desirable to use in wheat breeding programmes. The well-defined landmarks on the Am chromosomes could accelerate the targeted introgression of T. monococcum chromatin into the wheat genome.Fluorescence in situ hybridization (FISH) using the repetitive DNA probes pSc119.2, Afa family and pTa71 showed that the pSc119.2 probe was not suitable for the identification of Am chromosomes. In contrast, the whole set of Am chromosomes (especially chromosomes 1, 4, 5 and 7) could be discriminated based on the hybridization pattern of pTa71 and Afa family. In situ hybridization with microsatellite motifs (GAA, CAG, AAC and AGG) proved that SSRs represent additional landmarks for the identification of Am chromosomes. The most promising SSR probes were the GAA and CAG motifs, which clearly discriminated the 6Am chromosome and, when used in combination with the Afa family and pTa71 probes, allowed the whole set of Am chromosomes to be reliably identified.In conclusion, fluorescence in situ hybridization using the repetitive DNA probes Afa family and pTa71, combined with SSR probes, makes it possible to identify the Am chromosomes of T. monococcum and to discriminate them from Au chromosomes in the polyploid wheat background.
Cytokine production has been implicated in the pathogenic mechanisms of infections caused by the staphylococci, since these bacteria may act as strong cytokine inducers. To gain deeper insight into the Th1 immune response activated by these bacteria, we have analyzed the interferon (IFN), interleukin-12 (IL-12) and IL-18-inducing activities of different Staphylococcus aureus (S. aureus), S. epidermidis and S. saprophyticus strains in human monocytes and murine bone marrow macrophages. A large majority of the S. aureus strains elicited the simultaneous production of IL-12 p70 and IFN-a in the human monocytes, while the S. epidermidis and S. saprophyticus strains induced only a low level of production, if any, of these cytokines. Furthermore, a majority of the S. aureus strains induced significantly higher IL-12 p70 and IL-18 titers in the murine bone marrow macrophages than did the S. epidermidis and S. saprophyticus strains. As IL-12, IL-18 and IFN-a stimulate Th1 differentiation synergistically, we suggest that S. aureus strains bias the immune response toward a Th1 phenotype, whereas S. epidermidis and S. saprophyticus strains provide a weaker stimulus for the production of Th1-inducing cytokines, and accordingly possibly elicit a less extensive Th1-associated adaptive immunity.
Six cropping populations, three variety mixtures and one diversity population were developed from winter wheat varieties and studied for physical, compositional and end-use quality traits for three years (2011–2013) under different European climatic and management conditions in order to study the stability of these traits resulted by the genetic diversity. The beneficial compositional and nutritional properties of the populations were assessed, while variation and stability of the traits were analysed statistically. No significant differences were found among the populations in low-input and organic management farming systems in the physical, compositional and processing properties, but there was a difference in the stability of these traits. Most of the populations showed higher stability than the control wheat variety, and populations developed earlier had higher stability than those developed later. Furthermore, some populations were found to be especially unstable for some traits at certain sites (mostly at Austrian, Swiss and UK organic sites). Protein content of the populations was high (13.0–14.7%) without significant difference among them, but there was significant variation in their gluten content (28–36%) and arabinoxylan content (14.6–20.3 mg/g). The most outstanding population for both protein and arabinoxylan content was a Hungarian cropping population named ELIT-CCP. It was concluded that the diversity found in the mixtures and CCPs have stabilizing effect on the quality parameters, but a higher stability was observed under low-input than under organic conditions. These results could be beneficial not only for breeders but also for the consumers in the long run.
