5) A diminutive "midget" chromosome was found in plants containing a wheat nuclear genome with a substituted rye cytoplasm. This cytoplasmic substituted line arose during successive backcrossing of a wheat/rye amphiploid to wheat as the recurrent male parent. SOUTHERN and in situ hybridization with a dispersed repeat sequence specific for rye, R173, indicates that the midget chromosome originates from within the rye genome. Various DNA markers previously mapped to group 1 chromosomes of wheat and barley were used to trace the origin of the midget chromosome from within the rye genome. Ten short arm and 36 long arm probes were used and one marker was identified, which hybridizes to the midget chromosome and maps to the proximal region of the long arm of chromosome 1R. An additional marker was generated from a genomic library of the line containing the midget chromosome. This also maps to the long arm of 1R. The results indicate that the midget chromosome contains a small segment of the long arm of chromosome 1R.
6) M. SCHRIBAUX bred on the French experimental station “Cappelle” new wheats derived from crosses of “Krelof” wheat (from Sahara oasis) x “iI” (Rieti x Epi carè x Inversable); he expected great benefit for French agriculture because of kryptic disease resistance and high yields (210)
7) In western European wheats, resistance genes from the French wheat “VPM1” wereintroduced, they are possessing chromosomal translocations from Aegilops ventricosa and thus resistance to rusts, eyespot and nematodes; the the VPM1 line derives from the cross Ae. ventricosa x T. persicum (T. turgidum var. carthlicum)// 3*Marne (T. aestivum) (212)
8) A different type of 1AL.1RS* translocation as compared to the “Amigo” type (223)
9) Six wheat cultivars reported to have 1B/1R wheat-rye translocations and, presumably, Yr9, and two rye cultivars were inoculated with four races of Puccinia striiformis ssp. tritici and tested with 9 of the 16 RGAP markers. Results of these tests indicate that “Clement”, “Aurora”, §Lovrin 10”, “Lovrin 13”, and “Riebesel 47/51” have Yr9 and that “Weique” does not have Yr9. The 1B/1R translocations of “Benno”, “Perseus”, “Kavkaz” and “Avrora” were not distinguished from the 1B/1R substitutions of the wheat strains “W565/52”, “Salzmünde 14/33” and “Weique-Substitution”. “Consul”, “Maris Huntsman”, “Stella” and “Weique” possessed a capacity for partial fertility restoration but only “Professeur Marchal” was capable of restoring fertility completely and even within this variety lines and sublines differed in this respect.
Data on pairing of “Weique Züchter”, which has a deviant 1B-1R chromosome lacking the telomeric band on the long arm, showed that this chromosome can pair with 1RS and 1BL.
The high quality cv “Ferdinand” had a complete 1B/1R substitution and thus lacked the low molecular weight glutenins on 1BS and the high molecular weight glutenins on 1BL, and apart from the old German cv. “Weique”, is the only substitution cultivar known to date.
10) Revealed by monosomic analysis, i.e., homoeologous recombination for hairy peduncle, brown spike, and red grains
11) Two winter alleles of Vrn-A1 were recently found in wheat cultivars adapted to the Great Plains of the USA. Using a diagnostic marker for a single-nucleotide polymorphism (SNP) in exon 4, which distinguishes the alleles, the allele in the Great Plains cultivar ‘Jagger’ was common in Australian and CIMMYT cultivars, but ‘Veery’ cultivars carried the alternate allele from their Russian ancestor, which was the same as the allele in the Great Plains cultivar ‘Wichita’. The ‘Wichita’ allele was in North American winter cultivars, and chromosome substitution lines with a high level of tolerance to freezing, but not in substitution lines with a lower level of tolerance. The SNP between the alleles alters the predicted Vrn-A1 protein sequence, and this potentially explains differences in freezing tolerance. We suggest that these winter alleles could be coded as Vrn-A1v for the ‘Jagger’ allele and Vrn-A1w for the ‘Wichita’ allele. Cultivars with the spring Vrn-A1a or Vrn-A1b alleles carried the same SNP allele as ‘Jagger’, suggesting that the mutation from winter to spring for these alleles occurred in a Vrn-A1v genotype. (Quelle: DOI: 10.1111/j.1439-0523.2011.01856.x)
12) Details http://www.wheatpedigree.net/sort/show/82753
13) Details http://www.wheatpedigree.net/sort/show/4124
14) Details http://www.wheatpedigree.net/sort/show/5312
15) Details http://www.wheatpedigree.net/sort/show/7296
16) Datails http://www.wheatpedigree.net/sort/show/84050
17) Details http://www.wheatpedigree.net/sort/show/7649
18) Details http://www.wheatpedigree.net/sort/show/8146
19) Details http://genbank.vurv.cz/wheat/pedigree/krizeni2.asp?id=59850
20) Details http://genbank.vurv.cz/wheat/pedigree/krizeni2.asp?id=59890
21) There is an additional reciprocal translocation between chromosome 5B and 7B of wheat
22) Translocated experimental line based on a selected variety or breeding strain, i.e., without sponateous translocation but more or less targeted introgression (cf. Figure 2)
23) C-banding revealed that the varieties Omskaya 37, Omskaya 38, Omskaya 41, in addition to wheat-rye translocation 1RS.1BL possess wheat-wheatgrass translocation 7DL-7Ai, where a segment of chromosome 7Ai of Agropyron elongatum (=Thinopyrum elongatum) is translocated to the long arm of wheat chromosome 7D. It is known that 1RS carries the genes Lr26, Sr31, Pm8, Yr9, while a translocation from Thinopyrum elongatum – genes Lr19 and Sr25 (McIntosh et al. 1995). Molecular analyses revealed that in the varieties Omskaya 37, Omskaya 38, Omskaya 41 resistance to leaf rust is determined by genes Lr26 + Lr19, to stem rust – Sr25, Sr31. Varieties carrying Lr19 gene were introduced into Volga region of Russia in the late 1980s. Resistance controlled by Lr19 was defeated at the end of 1990s due to broad cultivation of varieties with this gene in Volga regions (Sibikeev et al., 2011). However, combination of genes Lr19+Lr26 protects plants against leaf rust pathogen. Moreover, the gene Sr25 ensures high level of protection against Ug99 race (Singh et al. 2008).
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