A Database for Triticeae and Avena
INSTITUTE OF EXPERIMENTAL BIOLOGY AT THE ESTONIAN AGRICULTURAL
76902, Harku, Estonia.
M. Tohver, R. Koppel*, and A. Ingver*.
* Jõgeva Plant Breeding Institute, Jõgeva MK, 48309.
Wheat breeding in Estonia was established by Earl Berg in the
mid 19th century. Wheat cultivation became more popular in the
1920s and 1930s as the result of experiments and publications
by the Jõgeva Plant Breeding Institute. Under Soviet rulers,
the baking quality of wheat in Estonia was strongly influenced
mostly by the wheat cultivars Leningradka and Mironovskaya 808
from Russia and Arkas from Germany. Recent breeding efforts have
involved cultivars and breeding lines mainly from Scandinavian
countries, where the climatic conditions are similar to those
in Estonia. Today, foreign cultivars that are early and high in
protein content, and have optimal gluten content and quality,
good resistance to sprouting, and high-yield ability are selected
as crossing parents (Koppel and Ingver 1999).
One of the objectives of wheat breeding in Estonia is high-quality
grain for baking. In 1994, coöperation began with Finnish
Boreal Plant Breeding. A number of spring wheat breeding lines
from different generations arrived. In 1997 and 1998, the composition
and HMW-glutenin subunits of 27 advanced breeding lines obtained
from Boreal and 12 foreign cultivars, all grown in Estonia, were
determined using A-PAGE and SDS-PAGE. This investigation was made
in coöperation with the Jõgeva Plant Breeding Institute
and Institute of Experimental Biology.
Payne and coworkers (1981) demonstrated a clear relationship
between the glutenin subunit composition of wheat grain and baking
quality that could be used as a selection criterion in breeding
programs. These results were confirmed and extended to other quality
tests using other genotypes in different countries.
In our work, a limited number of combinations of HMW glutenin
was established in the advanced breeding lines. The most common
represented alleles were Glu-A1b (2*), Glu-B1b (7+8),
Glu-D1a (2+12), and GluD1d (5+10). Two advanced
breeding lines contained HMW-glutenin bands 14+15 encoded by the
Glu-B1. The lines also were evaluated for agronomic and
baking quality. Nine of the 27 lines were suitable as donor cultivars
in improving baking quality, and four were preserved in the genebank
as carriers of some unique qualities (e.g., rare glutenin composition,
good sprouting resistance). Tests confirmed the suitability of
the three lines to be put on the Variety List. "The comparison
of spring wheat breeds" by R. Koppel was based on this work
and a Master of Science thesis was defended in June 1999. This
study represents the first attempt to investigate the allelic
variation of storage proteins in the wheat material used in breeding
The subunits of glutenin were resolved by SDS-PAGE, the established
method of identifying and cataloguing the various subunits (Payne
and Lawrence 1983). Catalogs of wheat glutenin subunits have been
created for many cultivars in several countries. To develop new
cultivars with improved bread making quality, it would be useful
to cross genotypes having complementary subunits of good quality
coded by different loci and then to select progeny with high Glu-1
scores. The combination of HMW subunits as 1 (Glu-A1a),
7+9 (Glu-B1c), and 5+10 (Glu-D1d) give a good quality
score of 9, and subunits 2* (Glu-A1b), 7+8 (Glu-B1b),
and 5+10 (Glu-D1d) give the maximum quality score of 10.
Varieties from Finland have a low variability for HMW-glutenin
alleles. The frequency of alleles encoding the subunits 2* at
Glu-A1, 7+8 at Glu-B1, 2+12 and 5+10 at Glu-D1
is high. Finnish cultivars have a high quality score of 8 (Sontag
et al. 1986) and have been strongly influenced by spring wheat
cultivars from Russia and Canada (Sontag-Strohm and Juuti 1997).
The limited number of combinations of HMW-glutenin subunits amongst
Finnish wheats is probably due to the long tradition of breeding
and growing wheat primarily for making bread (Sontag et al. 1986).
This knowledge could be used to find lines for our breeding program.
Wheat breeding will benefit greatly from the development of new
common wheat genotypes with high adaptability to the local growth
conditions by using germ plasm with wide genetic diversity.
Recent advanced spring wheat lines or varieties include Heta
and Manu from Estonia, Ulla from Finland, and Satu and Tjalve
H. Peusha, T. Enno, and O. Priilinn.
The introgressive wheat line SMT43 was selected in the progeny
of crosses between the hexaploid wheat cultivar Saratovskaya 29
and tetraploid hybrid F1 (T. militinae/T. timopheevii
subsp. timopheevii). Pentaploid hybrid F1s were backcrossed
to the female parent for 3-4 generations to restore fertility
with simultaneous selection of resistant plants on infection background.
The test for powdery mildew resistance was made on segments of
primary leaves of host plants. The powdery mildew isolate No.
6 (avirulence/virulence formula Pm1, Pm2, Pm3a,
Pm6, Pm1+Pm2+Pm9, Pm16/Pm3b,
Pm3c, Pm3d, Pm3e, Pm4a, Pm4b,
Pm5, Pm8) used for the inoculation was selected
from single spore progeny and was kindly provided to us by Dr.
F. Felsenstein. The methods used for inoculation of the leaf segments
and the disease assessment were previously described by Lutz et
al. (1992) and Peusha et al. (1996). A set of the 21 monosomic
lines of Chinese Spring was used in a monosomic analysis of the
line SMT43 to determine the chromosomal location of the resistance
The F2 progenies from crosses between the Chinese Spring monosomic
lines and the introgressive line SMT43 showed a segregation ratio
of 3:1 resistant to susceptible plants in 20 cross combinations
after inoculation with powdery mildew isolate No. 6 (Table 1).
These data indicate that SMT43 possesses a single, dominant gene
conferring resistance. The progeny from the cross with monosomic
6B deviated significantly (P < 0.01, c2 = 7.142) from the expected
ratio, indicating that a dominant resistance gene for powdery
mildew is located on this chromosome.
Several examples of transfers of genes for resistance from
cultivated and wild relatives of Triticum to commercial
hexaploid wheat have been reported. McIntosh (1998) communicated
that chromosome 6B carries resistance genes Pm11, Pm12,
and Pm20. Genes Pm11 and Pm12 are derived
from T. aestivum subsp. compactum and Ae. speltoides
(Miller et al. 1988; Jia et al. 1996; McIntosh 1998), respectively.
Gene Pm20 was transferred to common wheat from the cultivated
rye Prolific (Friebe et al. 1994).
We believe that this new resistance gene located on chromosome
6B is not identical to any of the above mentioned genes, because
it evidently was introduced to line SMT43 from T. timopheevii
The participation of chromosome 6B in reciprocal translocations
in disease-resistant introgressive lines 146-155-T and SMT34,
derivatives of T. timopheevii subsp. timopheevii
and T. militinae, was confirmed earlier by C-banding analysis
of mitotic metaphase chromosomes (Badaeva et al. 1995).
The dominant powdery mildew resistance gene Pm27, located on
chromosome 6B in the introgressive line 146-155-T, was introduced
from T. timopheevii subsp. timopheevii. RFLP and
microsatellite analyses detected a T. timopheevii subsp.
timopheevii translocation on the 6B common wheat chromosome
(Järve et al., in press).
Our phytopathological analysis revealed different reactions
of wheat lines 146-155-T and SMT43 after inoculation with the
available collection of powdery mildew isolates. However, to verify
that gene Pm27 of line 146-155-T is not the resistance
gene located on chromosome 6B in line SMT43, we intend to test
The method of cytogenetical analysis of microsporogenesis in
the F1 hybrid plants was described previously by Enno et al. (1998).
The cytological analysis of meiosis in the monosomic F1 hybrids
'Chinese Spring monosomic / SMT43' has revealed less regular chromosome
pairing at metaphase I compared with the disomic hybrid F1 (Table 2). Associations
between the chromosomes in the monosomic hybrids were rather weak,
resulting in premature disjoining of the bivalents and an increase
in the number of additional univalents. The mean number of bivalents
was lower and that of univalents higher in crosses with the monosomic
lines of chromosomes 3B and 7B. The mean number of bivalents was
greater and that of univalents lower in monosomic hybrids of chromosomes
1B and 5D. In these crosses, the mean number of chiasmata was
also the highest, 35.6 and 35.3, respectively. Chromosomes 3B
and 7B decreased pairing, whereas pairing increased with chromosomes
1B and 5D. In the monosomic hybrids F1, different frequencies
of multivalent associations at MI were observed. Hybrids F1 with
monosomic lines 2B and 6B had the trivalent configurations without
univalents, and, consequently, these chromosomes were involved
in the reciprocal translocations. On the basis of the frequencies
of trivalent formation, we can assume that introgressive line
SMT43 has the chromosomal interchange 2B/6B in relation to Chinese