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  • Author or Editor: M. Rakszegi x
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Finding and improving wheat cultivars with good adaptability to abiotic stress is an important objective in breeding programmes. An experiment was set up in the climate chamber of the Martonvásár phytotron to test the effect of heat and drought stress on two winter wheat varieties and one variety of durum. Wheat plants exposed to 35°C and drought during grain filling exhibited altered agronomic and grain quality characteristics. Drought was found to have a much greater influence on yield and quality than heat stress. Reductions in the unextractable polymeric protein fraction and the glutenin-to-gliadin ratio indicated poorer grain yield quality as a result of drought, despite higher protein content. Quality deterioration was observed after drought, while heat stress had no noticeable influence on the protein quality of the three wheat genotypes, measured using size exclusion high performance liquid chromatography (SE-HPLC). The durum variety had a better ratio of protein components and a significantly higher Zeleny value when exposed to heat stress, although it had the lowest grain yield and grain/straw ratio.The most significant negative correlation was observed between the Zeleny value and the unextractable polymeric protein (UPP%) fraction after heat treatment and between the relative protein content and the albumin+globulin % (AG%) in the case of drought. These correlations testify that these parameters play an important role in determining the baking quality of wheat flour.

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A total of 266 Martonvásár (Mv) wheat (Triticum aestivum L.) accessions, including varieties and advanced lines, were examined using the “Perfect” molecular markers to detect the Rht-B1b (formerly Rht1) and Rht-D1b (formerly Rht2) semi-dwarfing genes. The gene Rht-B1b was detected in a total of 221 (83.5%) accessions. The Rht-D1b allele was found in fewer accessions. Overall 24 genotypes (9%) contained this allele. The analysis of the development date of the genotypes revealed that the introduction of the dwarfing genes into Martonvásár breeding programmes started in the early 1970s, and they were widely utilized from the 1980s. The Rht-B1b allele was the main source for reducing plant height, while the Rht-D1b allele played only a minor role in the Martonvásár breeding programme.Characterizing accessions using various molecular markers allows us to create a database offering relevant marker information about genotypes. Such a database could be very helpful for selection, allowing breeders to include varieties giving positive results in specific breeding programmes.

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The genetic diversity of cultivated spelt (Triticum aestivum ssp. spelta) presently is narrow. Evaluation of germplasm collections of spelt on quality level supplemented with DNA analysis is, therefore, of great importance. This study was designed to help the evaluation process for the selection of new spelt varieties with a support of molecular characterization. A total of 30 genotypes, including two common wheat varieties, were included in the evaluation of genetic diversity on quality and DNA levels. According to the quality attributes, spelt flours exhibited medium rheological parameters and many of them had average gluten quality. AFLP analysis was conducted to evaluate phylogenetic relationships and the genetic diversity present in the accessions. A high level of genetic diversity was revealed by the very high PIC values. Two main clusters could be separated on the dendrogram: a cluster with genotypes that have common wheat in their pedigree and another cluster consisting of pure spelt accessions. The extent of genetic diversity in the spelt germplasm collections was confirmed not only by molecular markers but on the basis of quality assessment.

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Damaged starch, protein and arabinoxylan (AX) content and composition have been related to water absorption (WA) in a large set of samples. We tested 20 modern bread wheat cultivars bred in Hungary, 20 old Hungarian landraces, and 17 cultivars with special biochemical/functional characteristics from all around the world, this last set for international comparison. Grain was field grown in the 2011 and 2012 harvest seasons. Alinear mathematical model has been developed to estimate WA from protein content, starch damage, AX content and the relative amount of soluble proteins with strong correlation (r2 = 0.65) between measured and estimated data. The introduction of a new parameter, related to the cultivar dependent quantitative composition of soluble proteins and determined by lab-on-a-chip (LOC) analysis, largely improved the predictability of WA. Based on the large variation among the level of AX and certain soluble protein components in wheat flour and their significant contribution toWA determination, it was concluded, that these properties could be appropriate target traits to alter them during wheat breeding programs to improve the WA of wheat flour.

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Wheat-based food has great importance in human nutrition: in European countries they provide 20–30% of the daily calorie intake, and additionally, the wholemeal and healthy food becomes even more popular. Mineral content in grains is dependent on genetic and environmental factors (varieties, soil type, geographical location of the growing area, etc.), therefore, it is complicated to estimate how many percentage of the daily micronutrient requirements can be covered by wheat-based products. In this study, copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), selenium (Se) and zinc (Zn) contents of 13 commercial wheat flour products, and the white flour and wholemeal of 24 winter type bread wheat varieties were studied to estimate the nutritional value of these products. All investigated samples were produced in Hungary. Significant variation was revealed in the case of all mineral elements in the different brands of wheat flours. Generally, the white flour enriched with germ showed higher mineral contents than the average values of normal white flours. Furthermore, the wholemeal has higher Cu, Fe, Mn and Zn, but not higher Se contents than the white flours. Mo content was also higher in some brands of white flour than in wholemeal.The investigated winter wheat varieties showed significant differences in the case of Fe, Mn, Se and Zn contents, but none of the varieties showed outstandingly high micronutrient content. The milling process — as it was expected — reduces the concentrations of four elements (Fe 33%; Mn 88%; Zn 71%; Cu 44%); however, the Se and Mo concentrations were not affected significantly. Using the average micronutrient content in the wholemeal of varieties, the daily Mn and Fe requirement can be covered by the consumption of about 250 g wholemeal. Additionally, the daily Mo requirement could be met by the daily consumption of 140–190 g of commercial white or wholemeal flour.

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The characterization of the old Hungarian varieties and landraces is an important part of Hungarian cereal research and breeding. Analysis of these germplasms with the most up-to-date methodologies results a broad scale of diversity of glutenin alleles, which proves their genetic heterogenicity. Exploitation of this attribute is an untapped possibility for developing modern varieties in our breeding programs. The previous research work revealed this diversity by SDS-PAGE analysis and MALDI-TOF technology. The powerful tool, the high throughput lab-on-a chip technique can facilitate the effectiveness of this function and decreases the cost of the analysis. This study demonstrates the application of this technique for analysing the old varieties. The allelic composition and their effects on bread making quality concluded by means of functional analysis.

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Cereal Research Communications
Authors: K. Tremmel-Bede, P. Mikó, M. Megyeri, G. Kovács, S. Howlett, B. Pearce, M. Wolfe, F. Löschenberger, B. Lorentz, L. Láng, Z. Bedő and M. Rakszegi

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.

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Acta Agronomica Hungarica
Authors: L. Sági, M. Rakszegi, T. Spitkó, K. Mészáros, B. Németh-Kisgyörgy, A. Soltész, F. Szira, H. Ambrus, A. Mészáros, G. Galiba, A. Vágújfalvi, B. Barnabás and L. Marton

Research with transgenic plants in the Agricultural Research Institute of the Hungarian Academy of Sciences is primarily related to applications that are essential for the genetic improvement of cereals. The two main directions are connected to wheat and maize breeding and are focused on improving agronomic and nutritional traits. This paper highlights experiments in these areas, which are conducted in national as well as international collaborations. The transparency of this work is ensured by the dissemination of information about approved confined field tests to the public via the internet.

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