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Cereal Research Communications
Authors: F. Akfirat, Y. Aydin, F. Ertugrul, S. Hasancebi, H. Budak, K. Akan, Z. Mert, N. Bolat, and A. Uncuoglu

genetic, cytogenetic and molecular analyses and its marker assisted selection. Theor. Appl. Genet. 104 :315–320. Laroche A. Characterization of Triticum vavilovii-derived stripe

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Chen, S., Xu, C.G., Lin, X.H., Zhang, Q. 2001. Improving bacterial blight resistance of ‘6078’, an elite restorer line of hybrid rice, by molecular marker-assisted selection. Plant Breed. 120 :133–137. Zhang Q

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Acta Veterinaria Hungarica
Authors: László Fésüs, Attila Zsolnai, István Anton, and László Sáfár

The first results of the Hungarian sheep prion protein (PrP) genotyping programme are discussed in this paper. To obtain initial genotype frequency data 10 commercial (Hungarian Merino, German Mutton Merino, Merino Landschaf, German Blackheaded, Suffolk, Texel, Ile de France, Charollais, Lacaune, British Milksheep) and 4 indigenous (Gyimes Racka, Hortobágy Racka, Tsigaja, Cikta) breeds were sampled in 2003 and 2004, and the PrP genotypes were determined by microsequencing analysis with capillary electrophoresis. In all commercial breeds, a higher number of sheep were genotyped in 2005 (3648) and in 2006 (3834) within the breeding programme to increase scrapie resistance, and the estimated frequency data were compared to the initial figures to evaluate the efficiency of selection. The new developments arising from the identification of the so-called ‘atypical’ scrapie cases are also discussed.

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Chlorophyll content is positively correlated with photosynthetic rate. However, little is known about the genetic correlation between grain yield and chlorophyll content in the same wheat mapping population. The primary goal of the study was to detect the genetic basis of grain yield and chlorophyll content and their possible roles in the genetic improvement of grain yield in wheat. Here, quantitative trait loci (QTLs) for grain yield and chlorophyll content were studied using a set of 168 doubled haploid (DH) lines derived from a cross between two elite Chinese wheat cultivars, Huapei 3×Yumai 57. The DH population and parents were evaluated for grain yield and chlorophyll content in three environments. A total of 11 additive QTLs and 6 pairs of epistatic QTLs were detected for grain yield and chlorophyll content. Loci, such as Xcfd53, Xwmc718 , and Xwmc215 on chromosomes (e.g. 2D, 4A, and 5D) simultaneously controling grain yield and chlorophyll content, showed tight linkages or pleiotropisms. Three novel major QTLs, qGY5D, qChla5D , and qChlb5D , closely linked with the PCR marker Xwmc215 on chromosome 5D, accounted for 10.32%, 12.95%, and 23.29% of the phenotypic variance, respectively. The favorable alleles came from Yumai 57.

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The aim of this study was to develop a PCR based assay for an efficient selection of Yr10 resistance gene in breeding material. The two primer pairs designed from the Yr10 gene sequence amplified specific DNA fragments in the genotypes carrying Yr10 and did not give a signal with near isogenic line and other lines containing different Yr genes. The genetic linkage of these molecular markers to Yr10 gene was tested on a segregating F 2 population derived from cross between the stripe rust resistant genotype carrying Yr10 (FLW10) and the susceptible line WH542. The data demonstrated that the markers derived from Yr10 gene sequence are completely linked to Yr10 , which will enable to combine this gene with other stripe rust resistance genes in wheat breeding programmes.

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Barley ( Hordeum vulgare L.) is one of the most economically important crops around the world. Diseases caused by fungi and viruses significantly reduce yield. The most important fungal diseases are leaf rust caused by Puccinia hordei , and powdery mildew caused by Blumeria graminis f. sp. hordei . The most economical and ecologically friendly way to avoid losses caused by these diseases is growing resistant varieties. Concerning practical breeding for powdery mildew and leaf rust resistance, simple, cheap and robust selection methods are required. Marker assisted selection (MAS) is of great potential to fulfil this demand. In this paper, we present development of a robust duplex marker for simultaneous selection of Rph7 , and presence of one of the following Mla alleles: Mla16, Mla19, Mla20, Mla21, Mla27 or Mla28 .

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A panel of 94 diverse hexaploid wheat accessions was used to map quantitative trait loci (QTL) underlying the yield related traits on chromosome 3A. Population structure and kinships were estimated using unlinked SSR markers from all 21 chromosomes. Analysis of variance revealed significant difference among accessions; however, genotype × year interaction was non-significant for majority of yield related traits. A mixed linear model (MLM) approach identified six QTLs for four traits that individually accounted for 10.7 to 17.3% phenotypic variability. All QTLs were consistently observed for both study years. New putative QTLs for the maximum fertile florets per spike and spike length were identified. This report on QTLs for yield related traits on chromosome 3A will extend the existing knowledge and may prove useful in marker-assisted selection (MAS) for development of high yielding cultivars.

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The location of major QTLs or even genes controlling abiotic stress tolerance is now possible by the application of marker-mediated techniques. This is achieved by exploiting precise genetic stocks, such as doubled haploids (DHs), recombinant substitution lines (RSLs) and recombinant inbred lines (RILs), along with the comprehensive genetic maps now available through the application of molecular marker techniques. These strategies are illustrated here showing how QTLs/genes affecting vernalization response, cold tolerance, osmotic adjustment, osmolite accumulation (free amino acids, polyamines and carbohydrates), salt tolerance and cold-regulated protein accumulation have been identified and located. Also, an example of marker-assisted selection (MAS) for frost tolerance is presented. Major loci and QTLs affecting stress tolerance in Triticeae have been mapped on the group 5 chromosomes, where the highest concentration of abiotic stress-related QTLs (vernalization response, frost tolerance, salt tolerance and osmolite accumulation) was located. A conserved region with a major role in osmotic adjustment has been located on the group 7 chromosomes.

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Acta Agronomica Hungarica
Authors: A. A. Belousov, V. M. Sokolo, Y. M. Sivolap, V. P. Domenjuk, and N. J. Storcheus

The performance of maize hybrids developed on the basis of recombined inbred lines (RIL) selected from an F2 hybrid population using marker-assisted selection (MAS) was studied. The task was to estimate the efficiency of DNA marker technology for intrapopulation selection and to study the performance of hybrids produced from marker-derived inbreds of the F2 population (GK 26 × Mo 17). Two hundred RILs of marker origin were crossed with 3 unrelated testcross lines from the Lacaune, Mindszentpuszta and Reid heterotic groups. An effective marker test system and informative marker criteria were elaborated for increasing MAS effectiveness. A two-locus system on the basis of linked SSR markers proved to be the most effective. The genetic improvement effect (ΔG) of the C1 population for plant productivity, plant height and grain length ranged from 9.1 to 16.1%, depending on the phenotypic trait and h2 level. The best hybrids developed on the basis of RILs of marker origin outyielded the national check for grain yield by 6.8-7.6%.

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The possibilities latent in molecular marker-based QTL analyses are presented through the example of studying winter survival and heading date in barley (Hordeum vulgare L.). The whole range of QTL experiments consists of several important steps, through which answers are found to the following questions: (1) How many QTLs are involved and where do they map, (2) How does the environment influence the effect of a QTL region (environment × QTL interactions), (3) When and where are the genes determining the given trait expressed (QTL dynamics), (4) What interactions occur between these QTLs and pathways leading to specific phenotypes, and (5) How consistent is the effect of a QTL region in different genetic backgrounds and in a wider range of germplasms (comparative mapping and association studies)? This knowledge then makes it possible to continue these experiments in the direction of marker-assisted selection and/or gene isolation through marker saturation of the relevant chromosomal regions and map-based cloning. The latter can give an insight into the exact mechanism through which the gene determines the phenotype.

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