ISSN 10227954, Russian Journal of Genetics, 2012, Vol. 48, No. 4, pp. 404–409. © Pleiades Publishing, Inc., 2012.
Original Russian Text © I.G. Adonina, N.V. Petrash, E.M. Timonova, Yu.A. Khristov, E.A. Salina, 2012, published in Genetika, 2012, Vol. 48, No. 4, pp. 488–494.
404
INTRODUCTION
A way to preserve and to increase the production of
common wheat
Triticum aestivum
L. grain is to
improve the productivity and to reduce the losses asso
ciated primarily with disease. Brown leaf rust is one of
the most common and harmful diseases of common
wheat and is caused by
Puccinia triticina
Eriks. Harvest
losses due to leaf rust may reach 30–50% [1].
Genetic protection is the most important element
of plant protection from biotic stress throughout the
world. To date, the chromosomal location in the com
mon wheat genome has been identified for more than
60
Lr
genes, which control leaf rust resistance [2]. A
substantial number of the
Lr
genes was transferred into
the wheat genome from the genomes of related spe
cies. For instance,
Aegilops speltoides
Tausch is a donor
of the
Lr28, Lr35, Lr26, Lr47
, and
Lr51
genes [3, 4].
However, the efficiency of individual
Lr
genes may be
lost with time because of the origin of new virulent
races of the pathogen.
This circumstance stimulates a search for new
resistance genes. Both donor species and previous col
lections of hybrid common wheat lines are suitable as
sources for this purpose.
Common wheat lines that carry genetic material
introduced from related species and are employed in
breeding can be conventionally divided into two pools.
A primary pool includes hybrid lines with multiple
introgressions, while a secondary pool combines
monotranslocation and isogenic lines. The multiplic
ity of introgressions in primary hybrids makes it diffi
cult to estimate the contribution of each fragment of
foreign genetic material transferred into the common
wheat genome into the formation of quantitative traits
and resistance to biotic and abiotic environmental fac
tors. Moreover, primary hybrids produce unstable
progenies when crossed with various common wheat
accessions. Hence, monotranslocation and isogenic
lines provide a unique and valuable source for breeding
aimed at transferring necessary genes into the com
mon wheat genome or their accumulation in the
genome.
For further studies, we chose line 73/00i with
Ae. speltoides
genetic material from our earlier collec
tion of common wheat lines carrying genetic material
introduced from
Aegilops
L. species [5], since the line
displayed high resistance to leaf rust for several years
[6]. The line was obtained by exposing
Ae. speltoides
pollen to ionizing radiation, which causes chromo
some breaks and facilitates multiple translocations.
The objectives of this work were to study the num
ber, locations, and sizes of the
Ae. speltoides
fragments
integrated into the genome of line 73/00i and to obtain
Construction and Study of Leaf RustResistant Common Wheat
Lines with Translocations of
Aegilops speltoides
Tausch.
Genetic Material
I. G. Adonina
a
, N. V. Petrash
a
, E. M. Timonova
a
, Yu. A. Khristov
b
, and E. A. Salina
a
a
Institute of Cytology and Genetics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia
email: adonina@bionet.nsc.ru
b
Siberian Institute of Plant Growing and Breeding, Siberian Branch, Russian Academy of Agricultural Sciences,
Krasnoobsk, Novosibirsk oblast, 630501 Russia
Received September 14, 2011
Abstract
—Genotyping was performed for the leaf rustresistant line 73/00i (
Triticum aestivum
×
Aegilops
speltoides
). Fluorescence
in situ
hybridization (FISH) with probes Spelt1 and pSc119.2 in combination with
microsatellite analysis were used to determine the locations and sizes of the
Ae. speltoides
genetic fragments
integrated into the line genome. Translocations were identified in the long arms of chromosomes 5B and 6B
and in the short arm of chromosome 1B. The Spelt1 and pSc119.2 molecular cytological markers made it pos
sible to rapidly establish lines with single translocation in the long arms of chromosomes 5B and 6B. The line
carrying the T5BS · 5BL5SL translocation was highly resistant to leaf rust, and the lines carrying the T6BS ·
6BL6SL translocation displayed moderate resistance. The translocations differed in chromosomal location
from known leaf resistance genes transferred into common wheat from
Ae. speltoides.
Hence, it was assumed
that new genes were introduced into the common wheat genome from
Ae. speltoides.
The locus that deter
mined high resistance to leaf rust and was transferred into the common wheat genome from the long arm of
Ae. speltoides
chromosome 5S by the T5BS · 5BL5SL translocation was preliminarily designated as
LrAsp5.
DOI: 10.1134/S1022795412020020
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