Institute for Plant Genetic Resources
4122 Sadovo-Plovdiv, Bulgaria.
Creating new high-yielding cultivars of soft winter wheat and triticale, ecologically plastic and suitable for our dry country regions.
D. Boyadjieva, Il. Stankov, As. Dimov, P. Stankova, Hr. Filipov, V. Vassilev, M. Mangova, and G. Rachovska.
Progress in the national project for
Creating
new high yielding cultivars of soft winter wheat and triticale,
ecologically plastic and suitable for our dry country regions'
at the IPGR, Sadovo, Bulgaria, in the period 1993-94,
is described. The methods of hybridization between cultivars
and species, as well as experimental mutagenesis, were used.
In this period, 19,541 cultivars, the progenies of intracultivar
and interspecific hybrids, hybrid-mutant populations of wheat
in the collection, early generations, and 1,550 triticales have
been studied. Furthermore, 1,400 new wheat lines and 335 triticales
have been studied in the advanced stages of breeding.
During the extremely dry conditions
of the period, the grain yields from a few cultivars were more
than 50 kg/ha.
In the advanced lines with complex
resistance to leaf and stem rusts and powdery mildew, line LC
284/4400 K was the best. Good resistance to the above three diseases
was shown in KC 919/4402 and 285-5. Candidate cultivar KC 559
(Zornitsa) and lines KC 868 and KC 494 were resistant to both
rusts. Candidate cultivar KC 845 (Strelets) was resistant to
stem rust and powdery mildew. LC 172, LC 275, and LC 157 had
resistance to leaf rust and powdery mildew. KM 19, KM 20, KM
59, KM 25, and KM 44 were resistant only to leaf rust. All the
lines had higher productivity than the standard cultivars.
Resistance to basal glume rot (Pseudomonas
syringae pv. atrofaciens (PSA)) and fusarial head
blight (Fusarium culmorum (FC)) of wheat and triticale
were studied in the field with artificial inoculation, at the
phenophases 9-10
(7-10
days before earring) and 10.5.4 (anthesis) by the growth stages
of Large (1954), according the methods of Vassilev et al. (1990).
In the large-scale screening with a high inoculum concentration
of the bacterial suspension (107 cfu/ml), only KM 22
had high resistance dating from April 26. The index of PSA attack
increased with increasing levels of the inoculum, described as
colony forming units per milliliter (cfu/ml), on the solid agar
medium. Resistance to PSA at 106 cfu/ml showed in
lines 83 S03-12, inoculated on April 28; IAS-20, inoculated on
April 29; Renan, inoculated on May 6; and GP 5012-3, inoculated
on May 17.
In the large-scale screening with medium
concentration of the fusarial suspension (104 cfu/ml),
Aldan and KC 969 (May 18) and CM 103705, Rugby, Enchruzilhada,
KC 552, KC 545, KC 872, and KC 873 (May 20) were not infected.
This year, Shanghai 3, Sumai 3, and Nobeoka Bozu were again highly
resistant to fusarial head blight.
Resistance to cold among 416 accessions,
e.g., 225 cultivars and lines of wheat, 108 triticale forms, and
83 lines of durum wheat, was studied in the project. They were
grown in metallic containers (30x40x7 cm) full of peat soil, vernalized
in the natural autumn-winter conditions, and transferred to the
low-temperature chamber at -17 C
when a tillering growth stage was reached.
High cold resistance, using Pobeda
as a standard, was found only in line KC 937. Cold resistance,
using Bezostaja 1 and Sadovo 1 as standards, was observed in lines
KC 948, KC 922, KC 545, KC 694, Brilyant, Diamant, Sadovo 552,
KC 772, Prelom, KC 912, and Vida.
Sources of resistance to low negative
temperatures with higher productivity, for further use in breeding
programs are KC 937, KC 575, KC 131, KC 498, KC 772, KC 550 (Gracia),
and KC 922 (Boryana).
Thirteen triticale lines were interesting
in that they achieved the high degree of cold resistance found
in the standard, AD 206.
Resistance to aluminum (Al) toxicity
of 100 cultivars and lines of wheat was studied. A significant
part of these had an index of root tolerance equal to 0.8 at an
Al level of 0.36 mM. Highly tolerant was the line K 609/3380
R, which at Al levels of 0.18, 0.36, 0.72, and 1.40 mM, had indices
of root tolerance at 1.05, 1.00, 0.92, and 0.89, respectively.
The highest values for the valorigraphic
and alveographic parameters and for bread baking were observed
for cultivars Pobeda and Momchil and candidate cultivars KC 747,
KC 749, KC 927, and KC 768, whose levels for the first two characters
placed them in the group of strong wheats. Candidate cultivars,
Gracia A and Gracia B, showed a very good volume of bread.
For creating winter wheat lines with
high grain quality by experimental mutagenesis, the biochemical
and technological properties of 14 M7 mutant lines
were studied. Seed treatment, by gamma radiation and sodium azide,
of cultivars Momchil, Pobeda, and Katya was used. Line 1062 M,
from Momchil, had a higher biological value of grain and properties
of a strong wheat. The high-yielding line, 1386 P, from Pobeda,
had larger grain than the parent (48 g) and a higher volume of
bread -
630 cm3.
Candidate triticale cultivars, TS 210
and TS 119, were presented to the Government for examination and
inclusion on the list of approved cultivars.
Seven cultivars were created and included
in the national list of the proved wheat cultivars: Sadovo 1,
complex standard; Pobeda, quality standard; Katya; Momchil; Bononiya;
Sadovska beliya; and the newest cultivar, Murgavets.
Publications.
Boyadjieva D. 1994. The results of
using different germplasm in the wheat breeding program for Bulgarian
dry conditions. In: Evaluation and Exploitation of Genetic Resources
-
Pre-Breeding. Eucarpia Meeting, March 15-18, 1994. Clermont-Ferrand,
France.
Dimov A, Zaharieva M, and Mihova S.
1993. Rust and powdery mildew resistance in Aegilops
accessions from Bulgaria. In: Biodiversity and Wheat Improvement
(Damania AB ed) John Wiley & Sons, New York. pp. 165-169.
Panayotov Iv, Boyadjieva D, Todorov
Iv, Stankov Il, Dechev D, and Tsvetkov S. 1994. Present situation
and problems of wheat breeding in Bulgaria. Plant Sci 31(3-4):48.
Wheat germplasm preservation, evaluation, and utilization.
S.D. Stoyanova and K.D. Kolev.
The long-term preservation of seeds is a method for preventing genetic changes in plant germplasm. As a result of collecting activity and of donations received from collaborating institutes, 8,652 seed accessions comprise the Triticum collection in the seed bank.
During 1984, 418 wheat accessions were
sown in the field. Twenty-seven bread wheat varieties, evaluated
as early maturing, were more productive under the extremely hot
and dry weather in May.
Seed storage proteins (gliadins) as
direct gene products and relatively free of environmental effects,
were used to study genetic integrity in the wheat collection.
Thirty-four bread wheat accessions and 20 durum wheat accessions
were analyzed by gliadin electrophoresis. Thirty-five of them
were composed of several biotypes differing by gliadin spectra.
Gliadin electrophoresis allowed the screening of biotype composition
in wheat varieties, as well as genotypes within species. It is
particularly useful for genetic analysis of gliadin blocks coded
by the short arm of the chromosomes of homologous groups 1 and
6. This technique may be used as a tool to identify wheat genotypes
and may aid in the development of investigations on the nutritional
and technical properties in wheat germplasm.
Publications.
Stoyanova SD. 1991. Genetic shifts
and variation of gliadins induced by seed ageing. Seed Sci Technol
19:363-371.
Stoyanova SD. 1992. Effect of seed
ageing and regeneration on the genetic composition of wheat.
Seed Sci Technol 20:489-496.
Stoyanova SD. 1994. Expression of
gliadin in a dominant mutation of wheat seeds. Seed Sci Technol
22:477-484.
Stoyanova SD and Kolev KD. Wheat germplasm
evaluation by gliadin electrophoresis. (In press).
Statistics Canada's November estimate of 1994 wheat production on the prairies:
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Hectares seeded Metric tonnes produced
______________________________________________________________________
Manitoba - spring 1,558,000 3,453,600
- durum 101,200 239,500
- winter 2,000 3,500
Saskatchewan - spring 4,491,900 8,518,400
- durum 1,922,300 3,864,600
- winter 12,100 25,900
Alberta - spring 2,144,900 4,945,000
- durum 323,700 694,000
- winter 32,400 76,200
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MANITOBA
Agriculture & Agri-Food Canada
Winnipeg Research Centre, 195 Dafoe Road,
Winnipeg, MB, R3T 2M9, Canada.
T. Aung, N.K. Howes, R.I.H. McKenzie, and T.F. Townley-Smith.
During the last 2 years, we have generated
large populations of wheat double haploids using maize pollen
and applying hormones (2,4-dichlorophenoxyacetic acid and GA3)
to spikes in split applications by atomization. We are using
environmental cabinets to raise hybrid wheat plants, short stature
maize, and haploid plants, enabling continuous year-round production.
For genetic studies of virus tolerance (WSMV, BYD), Fusarium
head blight, pre-harvest dormancy, high kernel protein, low polyphenol
oxidase, and extra-strong dough mixing characteristics, separate
populations of 50-200
double haploid plants for each study have been generated. Unlike
anther culture, the method was not genotype dependent. We have
produced double haploids from a wide range of Canadian hard red
spring, Canadian prairie spring, and spring/winter hybrids, but
timing of emasculation is critical.
We have improved the efficiency of
embryo production (average 5 embryos/spike), the differentiation
of embryos into haploid plants (up to 80 %), and the high survival
of plants after colchicine treatment with high efficiency of chromosome
doubling (above 90 %). In the last 2 months, we have been producing
more than 100 haploid plants per week (average >3 haploids/spike),
and over the last 18 months, we have produced 1,600 double haploid
lines and an additional thousand haploid plants are in the process
of being doubled. Even higher production rates seem achievable.
Observations of field-grown lines showed
great variability in phenotype between lines, but uniformity within
lines and good reproducibility between replicates, enabling easy
selection for some genotypes. The major limitations for applying
DHs to plant breeding programs are the resources available (growth
cabinets, greenhouse space) to grow haploids and DH lines to maturity.
Marker assisted selection at the haploid stage will enable unwanted
genotypes to be discarded and, thus, greatly improve efficiencies
especially where tests can be combined.