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I. M. Ben Amer A. J. Worland V. Korzun A. Börner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1997,94(8):1047-1052
Three quantitative trait loci (QTL) for tissue- culture response (Tcr) were mapped on chromosome 2B of hexaploid wheat (Triticum aestivum L.) using single-chromosome recombinant lines. Tcr-B1 and Tcr-B2, affecting both green spots initiation and shoot regeneration, were mapped in relation to RFLP markers in the centromere
region and on the short arm of chromosome 2B, linked to the photoperiod-response gene Ppd2. A third QTL (Tcr-B3), influencing regeneration only, was closely related to the disease resistance locus Yr7/Sr9g on the long arm of chromosome 2B. The homoeologous relationships to the tissue-culture response loci Qsr, Qcg and Shd of barley are discussed. A possible influence of the earliness per se genes of wheat and barley is suggested.
Received: 30 August 1996 / Accepted: 15 November 1996 相似文献
13.
Yong Jiang Albert Wilhelm Schulthess Bernd Rodemann Jie Ling Jörg Plieske Sonja Kollers Erhard Ebmeyer Viktor Korzun Odile Argillier Gunther Stiewe Martin W. Ganal Marion S. Röder Jochen C. Reif 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(3):471-482
Key message
Compared with independent validation, cross-validation simultaneously sampling genotypes and environments provided similar estimates of accuracy for genomic selection, but inflated estimates for marker-assisted selection.Abstract
Estimates of prediction accuracy of marker-assisted (MAS) and genomic selection (GS) require validations. The main goal of our study was to compare the prediction accuracies of MAS and GS validated in an independent sample with results obtained from fivefold cross-validation using genomic and phenotypic data for Fusarium head blight resistance in wheat. In addition, the applicability of the reliability criterion, a concept originally developed in the context of classic animal breeding and GS, was explored for MAS. We observed that prediction accuracies of MAS were overestimated by 127% using cross-validation sampling genotype and environments in contrast to independent validation. In contrast, prediction accuracies of GS determined in independent samples are similar to those estimated with cross-validation sampling genotype and environments. This can be explained by small population differentiation between the training and validation sets in our study. For European wheat breeding, which is so far characterized by a slow temporal dynamic in allele frequencies, this assumption seems to be realistic. Thus, GS models used to improve European wheat populations are expected to possess a long-lasting validity. Since quantitative trait loci information can be exploited more precisely if the predicted genotype is more related to the training population, the reliability criterion is also a valuable tool to judge the level of prediction accuracy of individual genotypes in MAS.14.
Bernd Hackauf Eva Bauer Viktor Korzun Thomas Miedaner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(6):1179-1189
Key message
A comparative genetics approach allowed to precisely determine the map position of the restorer gene Rfp3 in rye and revealed that Rfp3 and the restorer gene Rfm1 in barley reside at different positions in a syntenic 4RL/6HS segment.Abstract
Cytoplasmic male sterility (CMS) is a reliable and striking genetic mechanism for hybrid seed production. Breeding of CMS-based hybrids in cereals requires the use of effective restorer genes as an indispensable pre-requisite. We report on the fine mapping of a restorer gene for the Pampa cytoplasm in winter rye that has been tapped from the Iranian primitive rye population Altevogt 14160. For this purpose, we have mapped 41 gene-derived markers to a 38.8 cM segment in the distal part of the long arm of chromosome 4R, which carries the restorer gene. Male fertility restoration was comprehensively analyzed in progenies of crosses between a male-sterile tester genotype and 21 recombinant as well as six non-recombinant BC4S2 lines. This approach allowed us to validate the position of this restorer gene, which we have designated Rfp3, on chromosome 4RL. Rfp3 was mapped within a 2.5 cM interval and cosegregated with the EST-derived marker c28385. The gene-derived conserved ortholog set (COS) markers enabled us to investigate the orthology of restorer genes originating from different genetic resources of rye as well as barley. The observed localization of Rfp3 and Rfm1 in a syntenic 4RL/6HS segment asks for further efforts towards cloning of both restorer genes as an option to study the mechanisms of male sterility and fertility restoration in cereals.15.
16.
Reif JC Maurer HP Korzun V Ebmeyer E Miedaner T Würschum T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(2):283-292
There is increasing awareness that epistasis plays a role for the determination of complex traits. This study employed an
association mapping approach in a large panel of 455 diverse European elite soft winter wheat lines. The genotypes were evaluated
in multi-environment trials and fingerprinted with SSR markers to dissect the underlying genetic architecture of grain yield
and heading time. A linear mixed model was applied to assess marker-trait associations incorporating information of covariance
among relatives. Our findings indicate that main effects dominate the control of grain yield in wheat. In contrast, the genetic
architecture underlying heading time is controlled by main and epistatic effects. Consequently, for heading time it is important
to consider epistatic effects towards an increased selection gain in marker-assisted breeding. 相似文献
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E. Pestsova E. Salina A. Börner V. Korzun O. I. Maystrenko M. S. Röder 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,101(1-2):95-99
Ninety-five wheat microsatellite markers (WMS) were used to verify the authenticity of the set of Saratovskaya 29/Yanetzkis
Probat inter-varietal wheat chromosome substitution lines developed using Saratovskaya 29 as the recipient variety. Polymorphic
markers were available for all chromosome arms except 4DS, 6DS and 7DS. Each chromosome substitution line was tested by 2–8
microsatellite markers. The results demonstrate that most of the lines are correct. Out of 21 lines tested 17 showed the expected
microsatellite pattern of the donor variety. Two entire chromosomes, 1B and 7A, and two chromosome arms, 3AL and 6DS, were
not substituted with Yanetzkis Probat in their respective lines. Three microsatellite markers located in the distal regions
of chromosome arms 4AL, 3BS and 5BL in the corresponding substitution lines did not reveal the expected microsatellite pattern
of the recipient variety. The possible causes of the incorrect substitution line development and the appearance of incorrect
distal microsatellite markers are discussed. The data confirm the idea that microsatellite markers provide ideal tools for
testing the authenticity of genetic stocks of wheat.
Received: 27 August 1999 / Accepted: 8 October 1999 相似文献
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Cathérine Pauline Herter Erhard Ebmeyer Sonja Kollers Viktor Korzun Willmar Lukas Leiser Tobias Würschum Thomas Miedaner 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(6):1263-1272
Key message
The dwarfing gene Rht24 on chromosome 6A acts in the wheat population ‘Solitär × Bussard’, considerably reducing plant height without increasing Fusarium head blight severity and delaying heading stage.Abstract
The introduction of the Reduced height (Rht)-B1 and Rht-D1 semi-dwarfing genes led to remarkable increases in wheat yields during the Green Revolution. However, their utilization also brings about some unwanted characteristics, including the increased susceptibility to Fusarium head blight. Thus, Rht loci that hold the potential to reduce plant height in wheat without concomitantly increasing Fusarium head blight (FHB) susceptibility are urgently required. The biparental population ‘Solitär × Bussard’ fixed for the Rht-1 wild-type alleles, but segregating for the recently described gibberellic acid (GA)-sensitive Rht24 gene, was analyzed to identify quantitative trait loci (QTL) for FHB severity, plant height, and heading date and to evaluate the effect of the Rht24 locus on these traits. The most prominent QTL was Rht24 on chromosome 6A explaining 51% of genotypic variation for plant height and exerting an additive effect of ? 4.80 cm. For FHB severity three QTL were detected, whereas five and six QTL were found for plant height and heading date, respectively. No FHB resistance QTL was co-localized with QTL for plant height. Unlike the Rht-1 semi-dwarfing alleles, Rht24b did not significantly affect FHB severity. This demonstrates that the choice of semi-dwarfing genes used in plant breeding programs is of utmost consideration where resistance to FHB is an important breeding target.19.
V. Korzun A. Börner G. Melz 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1996,92(8):1073-1077
An F2 population was established for mapping the two dominant genes for dwarfness (Ddw1) and hairy peduncle (Hp) on chromosome 5R. The location of both genes was shown to be on the segment of chromosome 5RL which was ancestrally translocated and is homoeologous to Triticeae 4L. Hp cosegregated with the wheat gDNA probe WG199, localised in wheat on chromosomes 5AL, 4BL and 4DL. No segregation was observed between the traits hairy peduncle and hairy leaf sheath. The locus for Ddw1 was found to map distally to Hp/Xwg199 but proximal to the isozyme marker -amy-R1. The genetical distances were 5.6 cM between Hp/Xwg199 and Ddw1 and ll.ScM between Ddw1 and -amy-R1, respectively. The map position of Ddw1 suggests that it is homoeologous to the wheat dominant dwarfing gene Rht12, present on chromosome 5AL and linked to -amy-A1. 相似文献
20.
Miedaner T Wilde F Steiner B Buerstmayr H Korzun V Ebmeyer E 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2006,112(3):562-569
Fusarium head blight (FHB) is a devastating disease in wheat that reduces grain yield, grain quality and contaminates the harvest
with deoxynivalenol (DON). As potent resistance sources Sumai 3 and its descendants from China and Frontana from Brazil had
been analysed by quantitative trait loci (QTL) mapping. We introgressed and stacked two donor QTL from CM82036 (Sumai 3/Thornbird)
located on chromosomes 3B and 5A and one donor QTL from Frontana on chromosome 3A in elite European spring wheat and estimated
the effects of the three individual donor QTL and their four combinations on DON, Fusarium exoantigen content, and FHB rating adjusted to heading date. One class with the susceptible QTL alleles served as control.
Each of the eight QTL classes was represented by 12–15 F3-derived lines tested in F5 generation as bulked progeny possessing the respective marker alleles homozygously. Traits were evaluated in a field experiment
across four locations with spray inoculation of Fusarium culmorum. All three individual donor-QTL alleles significantly reduced DON content and FHB severity compared to the marker class with
no donor QTL. The only exception was the donor-QTL allele 3A that had a low, but non-significant effect on FHB severity. The
highest effect had the stacked donor-QTL alleles 3B and 5A for both traits. They jointly reduced DON content by 78% and FHB
rating by 55% compared to the susceptible QTL class. Analysis of Fusarium exoantigen content illustrates that lower disease severity is associated with less mycelium content in the grain. In conclusion,
QTL from non-adapted sources could be verified in a genetic background of German elite spring wheat. Within the QTL classes
significant (P<0.05) genotypic differences were found among the individual genotypes. An additional phenotypic selection would, therefore,
be advantageous after performing a marker-based selection. 相似文献