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The seed multiplication of genetically modified (GM) plants requires a modification of the multiplication process used for conventional seed. The difference compared to conventionally-bred varieties involves the detection of the modified character during variety maintenance, seed multiplication and processing, the need for separate storage, processing and transportation, the extra cleaning required for the transportation, storage and processing equipment, and the extra administration necessary for the documentation and labelling of GM seed lots. All in all this results in the lower exploitation of seed-producing capacity and in additional costs. The appearance of GM plants also has an effect on the breeders and seed multipliers of conventional varieties, however, since the possibility of contamination cannot be excluded. The producers of seed free of GMs (within the tolerance threshold) are forced to employ costly cultivation techniques (temporal and spatial isolation, removal of volunteer plants) and laboratory tests (for GM contamination) if their varieties are to stay on the market and if it is to remain possible to produce GM-free products in the future.

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In Hungary, stem rust epidemics caused by Puccinia graminis f. sp. tritici are rare, but due to the severity of infection the stem rust fungus can pose a great hazard to wheat production. As new virulent races can appear, it is important for breeders to know of the genetic background of the stem rust resistance in their cultivars. In this study, 220 winter wheat cultivars registered in Hungary in the past 35 years were investigated using molecular markers to determine the presence or absence and frequency of the two important stem rust resistance genes Sr31 and Sr36. The results indicated that both Sr31 and Sr36 genes are widespread in wheat cultivars registered in Hungary. Sr31 was detected in 24.1% of these wheats, and Sr36 in 15.9%. These genes occurred to a somewhat larger extent in the 156 local cultivars: one-third (32.1%) had the Sr31 and 18.0% the Sr36 gene. Of these, 2 cultivars (1.3%) had both genes (Sr31+ Sr36). Among the 64 foreign cultivars only 3 (4.7%) carried the Sr31 gene. In the foreign group, Sr36 was only detected in the seven Croatian cultivars. Tests also revealed possible false pedigrees for some cultivars. Inoculation tests showed that both genes were still effective. One-sixth (16.7%) of stem rust resistant cultivars did not carry the target genes indicating the possible presence of other efficient Sr genes. Data may help breeders to incorporate effective Sr genes into new cultivars.

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Central leader and vase form tree models were built using Finite Element Modelling (FEM). Their main characteristics were chosen to be the same. To get comparable results to real values, acceleration versus time curves of the two types of real trees were processed using FFT method to determine their natural frequencies. The natural frequencies measured on real trees and calculated for the models have shown good similarity. The models were virtually exposed to the effect of horizontal forced vibration in the frequency range of 0–20 Hz. Acceleration-frequency curves were calculated and drawn to find the best frequency values for the highest accelerations and also to see their differences in the limb. For the same purpose, the direction of shaking was also changed. It was found that for the central leader limb shape multidirectional shaking would bring uniform detachment, while for the vase form trees, even the unidirectional shakers are appropriate. Real trees were also shaken and their acceleration-frequency curves were compared with the values of the FEMs. The resultant good similarity proves the ability of the models. The acceleration values achieved in the vase form models were much higher than for the central leader type. The acceleration-frequency curve of the shaker unit can be used to find the best frequency for shaking.

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The storage of wheat data in computers began in the mid-eighties in Martonvásár, and was accompanied by the development of the first simple programs to assist the data management of routine breeding tasks. The great expansion of breeding materials and the demand for new applications have led to an enormous increase in the number of data and have made data processing increasingly more complicated. Data storage facilities and computer programs reflecting an outdated technological level were unable to keep pace with developments. Data storage and applications had to be redesigned on new lines to create a completely new information system amalgamating know-how from breeding and informatics.The paper introduces an extremely important part of this system: pedigree records, which contain the designations of all the genotypes included in traditional field breeding programmes and in the gene bank, together with crossing data, phenotypes and genomic data.An up-to-date, consistent pedigree register is one of the key components in the breeding information system, without which the maintenance and alteration of the names of plant species (wheat, barley, oats, etc.) and linking them to experiments and experimental quality data would be an extremely complex, time-consuming task. It would be even more difficult to keep track of all the genotypes and the increasingly large numbers of related lines from year to year.In addition to describing the rationale behind the system, details will be given on the tools and conditions required for the establishment of the pedigree records, and the internal and external sources available. Finally, some practical examples will be given of how the Martonvásár wheat breeding information system has been applied.

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Both resistance genes Lr19 and Lr24 originate from Agropyron elongatum . The gene Lr24 is derived from two different translocations: 1BS/3Ag (‘Amigo’) or 3DS/3Ag (‘Agent’). The use of molecular markers makes selection easier during the breeding process as well as in the selection of the parents. In this study, two markers were used to identify the gene Lr19 (GbF/R 130 , SCS265 512 ) and four different markers (J9/1-2 310 , SC-H5 700 , SCS1302 613 and SCS1326 607 ) were available to search for the gene Lr24 . The GbF/ R130 marker for gene Lr19 worked well, but the SCAR marker SCS265 512 proved to be easier to use in MAS. SCAR markers SCS1302 613 and SCS1326 607 proved to be highly reliable and effective for gene Lr24 not only in Agent-derived sources but also in ‘Amigo’ derivatives. The STS marker J9/1-2 310 and the SCAR marker SC-H5 700 required several modifications and were effective only in ‘Agent’ offsprings.

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Acta Agronomica Hungarica, 48(3), pp. 227–236 (2000) OCCURRENCE OF THE 1RS/1BL WHEAT–RYE TRANSLOCATION IN HUNGARIAN WHEAT VARIETIES B. K Ő SZEGI, G. LINC, A. JUHÁSZ, L. LÁNG and M. MOLNÁR-LÁNG AGRICULTURAL RESEARCH INSTITUTE OF THE HUNGARIAN ACADEMY OF SCIENCES, MARTONVÁSÁR, HUNGARY Received: August 15, 2000; accepted: October 15, 2000 The translocation which involves the substitution of the short arm of the 1R rye chromosome for the short arm of the 1B wheat chromosome by means of centric fusion has exercised an enormous influence on the world’s wheat breeding. Since the first mention of this translocation in 1937 the incidence of the 1RS/1BL translocation has been reported in connection with several hundred wheat varieties. Varieties carrying the translocation possess a chromosome segment which includes the resistance genes Sr31 (stem rust, Puccinia graminis), Lr26 (leaf rust, P. recondita), Yr9 (yellow rust, P. striiformis), Pm8 (powdery mildew, Erysiphe graminis) and Gb (aphid, Schizaphis graminum). The present paper investigates the occurrence of the 1RS/1BL translocation in wheat varieties bred in Hungary in recent years. It was found that 35 (53%) of the 66 Hungarian-bred wheat varieties registered in Hungary between 1978 and 1999 carried the 1RS/1BL translocation.

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The widespread use of digitally-controlled measuring and analytical devices and electronic data collectors, all equipped with microprocessors and linked to computers, has made it possible for on-line data collection to become a routine process. A rational combination of two up-to-date techniques, barcodes and digital balance terminals, linked to an average computer background (Kuti et al., 2003), has proved in practice to satisfy the criteria raised for the up-to-date processing of breeding data at low cost. This system is an example of how it is possible to reduce costs while processing data more rapidly and reliably and allowing human resources to be utilised more flexibly and efficiently. The modules (MvLabel, MvSticker, MvWeighing)of the program package developed in Martonvásár for the handling and analysis of the data from plant breeding and crop production experiments can also be used independently for the identification of experimental field units (spikes, rows, plots) and for the online handling of weight measurements and analytical data. They provide a simple solution for the design and printing of labels (self-adhesive or plastic) containing barcodes. They make it easier to retrieve the data recorded by digital balance terminals and store them on hard discs, while also helping to unify and synchronise the various parts of the system using barcode readers to identify the measurement data.

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The effect of vernalization response and photoperiod sensitivity on reproductive fitness and agronomic traits was examined in a group of 16 H. spontaneum accessions and 8 H. vulgare cultivars in controlled environments. The whole range of plant developmental and agronomic traits was determined by vernalization. The reproductive fitness was severely impaired when the vernalization requirements of the plants were not saturated. Variation in the magnitude of vernalization response significantly correlated with several traits. A larger decrease in reproductive tiller number, average seed number and consequently final grain yield was more characteristic of accessions with a greater vernalization response. When the vernalization requirement was met, long photoperiod enhanced the fitness of the plants and resulted in larger yield and yield components, irrespective of the genotype, while short photoperiod acted as a limiting factor for all these traits. There was, however, a difference in the reaction type of wild and cultivated genotypes due to their different plant strategies.

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Tillering ability is a complex trait, the development of which is influenced by both environmental factors and complex genetic regulation. In the present experiments this complex regulation was dissected into its various components in an effort to separate the effect on tillering of major genes influencing ontogeny from that of other genomic factors. The tillering rate of a facultative × winter barley mapping population was examined in the field after autumn and spring sowing. The vernalisation sensitivity gene Vrn-H2 exerted a considerable influence on tillering in spring-sown barley. In addition to the major genes, QTL analysis revealed two chromosome regions (1HS and 3HL) with a significant influence on the extent of tillering. Neither of these regions were involved in the regulation of heading date, and their effect on tillering was the most intense at the beginning of ontogeny, gradually declining as the influence of the Vrn-H2 gene increased. The function of the Vrn-H2 locus in the regulation of tillering is manifested partly through a direct effect on the transition from the vegetative to the generative phase and partly indirectly via epistatic regulation of other chromosome regions influencing tillering.

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