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cultivars Avrora, Kavkaz, Skorospelka 35 and Bezostaya 2. Bedő et al. ( 1993 )
demonstrated the presence of the 1RS.1BL translocation in the cultivars Martonvásári
(Mv) 14, Mv 15, Mv 16, Mv 17, Mv 18, Mv 19, Mv 20, Mv 21, Mv 22 and Mv 23.
On the basis of their pedigrees the translocational chromosome originated from four
different sources: in Mv 14, Mv 15, Mv 16 and Mv 20 from Kavkaz, bred in
Krasnodar, in Mv 18 from Solaris, bred in Solary , Slovakia, in Mv 21 and Mv 22
from Posavka 2, bred in Novi Sad, Yugoslavia and in Mv 19 from GT 5239-2, bred
in General Toshevo, Bulgaria. Kavkaz is among the ancestors of Solaris, and
Skorospelka 35 among those of Posavka 2, while Avrora is the source of the trans-
location in the case of GT 5239-2.
Wheat-rye chromosome substitutions and translocations have had a great infl u-
ence on quality improvements. Although the gene complex originating from rye
carries numerous disease resistance genes, these are combined with an unfavourable
effect on the technological quality, partly due to the presence of gamma secalin
instead of omega and gamma gliadins, and partly to the lack of the LMW glutenin
subunits found on wheat chromosome 1BS (Dhaliwal et al. 1988 ). The substitution
of the seed storage proteins of wheat by those of rye ( Secale cereale ) in the 1RS.1BL
translocation line resulted in inferior wheat quality (Lukaszewski 1993 ). The unde-
sirable technological traits include small loaf volume and sticky crumb (Zeller
1973 ), together with poor rheological traits. Breeders have made considerable
efforts in recent years to eliminate unfavourable technological quality by incorpo-
rating the translocated fragment into chromosomes of homoeologous group 1 or by
altering the present genetic background. Graybosch et al. ( 1990 ) drew attention to
the fact that a change in the genetic background could considerably modify the
unfavourable traits arising when the fl our is used for bread-making. Similar conclu-
sions were drawn by Javornik et al. ( 1991 ) when analysing the cultivars Jugoslavia,
Balkan and Zvezda, which have good bread-making quality and contain the
1RS.1BL translocation. Results obtained in Martonvásár, Hungary, also suggest that
a favourable genetic background is capable of reducing the deleterious effect of the
1RS.1BL translocation, but it cannot be completely eliminated and a negative infl u-
ence on quality must generally be expected (Bedő et al. 1993 ). Knackstedt et al.
( 1994 ) reported a new wheat-rye translocation on the long arm of chromosome 2B,
carrying a resistance gene against Hessian fl y, which did not infl uence the wheat
storage proteins or the technological quality.
A method was elaborated for the effi cient introduction of new allelic variation
into 1RS chromosome arm in wheat cultivars with 1RS.1BL translocation by
Molnár-Láng et al. ( 2010 ). A wheat genotype containing both the recessive cross-
ability alleles ( kr1kr1kr2kr2 ) allowing high crossability between 6 x wheat and dip-
loid rye , and the 1BL.1RS wheat/rye translocation chromosomes was developed.
This wheat genotype was used as a recipient partner in wheat × rye crosses.
Chromosome pairing between the 1BL.1RS translocation and the 1R chromosome
of the rye cultivar was detected in meiosis of the wheat × rye hybrids using sequen-
tial GISH and FISH, thus recombination occurred between the 1RS arms (Molnár-
Láng et al. 2014 ).
Z. Bedő and L. Láng