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BY JEREMY SIMES
GRAIN
SCIENCE
NEWS
Thebiggest yet
WHEAT GENOMEMAPSWORLDOF POSSIBILITIES
THE LABOUR-INTENSIVE TASK OF
decoding one of the world’s highly con-
sumed wheat varieties has made headway
in Saskatoon, SK.
Led by the University of Saskatchewan’s
Curtis Pozniak, under the Canadian
Triticum Advancement Through Genom-
ics (CTAG), the project’s goal is to create
a supreme reference genome sequence of
the bread wheat genome using DNA from
the Chinese Spring variety.
Sequencing the entire genome will cost
about $21.6 million. The CTAG project
alone received $8.5 million in funding,
with $1.6 million going towards the
sequencing and assembly of chromosome
1A. In fact, the wheat genome is five times
larger than the human genome, and only
20 per cent of it contains genes.
Due to the large size and complex struc-
ture of the bread wheat genome, substan-
tial barriers have made it di cult for re-
searchers to map it fully. However, recent
technological advances mean researchers
can now undertake the hefty task.
“We can develop a high-quality refer-
ence sequence in a much more rapid way
because of new technology that wasn’t
available four or five years ago,” explained
Pozniak.
In particular, Canada will sequence
chromosome 1A, which contains key genes
that determine dough strength and disease
resistance. As a global e ort, CTAG will
also work on chromosome 1A with re-
searchers in Switzerland and Turkey.
“There are a lot of interesting genes on
1A. Many quality aspects reside on it,”
Pozniak said. “But the project goes beyond
1A. We have access to other breeding in-
formation through international partners
that we may want to use.”
Once sequenced, the e ciency of
selecting specific traits will be greatly
enhanced for breeders who will develop
new varieties, said Kofi Agblor, managing
director of the Crop Development Centre
in Saskatoon.
“Ultimately, the project will help pin-
point varieties that impact producers, im-
proving their outcomes by using a product
that has less quality issues.”
Cultivars must continually be improved
to cope with changes in the production
environment—it reduces the dependence
on pesticides and production costs, and
provides marketing advantages, attract-
ing consumers and exporters, said Chris
Barker, chief scientific o cer at Genome
Prairie.
“Having a wheat genome sequence
is a blueprint. It impacts possible varie-
ties coming out from programs, and it’s
important to have the best varieties used
on farms.”
Canada will also develop a database
of all the genes, which can be used for
future marker-assisted selection and ge-
nome-wide selection strategies.
Genome selection is about taking new
technology to the next level, Barker added.
“Advances in technology allow you to
build that database, and understand all
of those regions in the chromosome,” he
explained. “There’s never an ideal variety
because things are constantly changing.
The strategies are really about allowing
breeders to be more productive to provide
better products for farmers.”
The project will examine four more
additional objectives: sequencing the
exome of key Canadian wheat cultivars;
identify single nucleotide polymorphism
(SNP) markers; developing high-through-
put SNP genotyping for wheat breeding;
and examining the role of public breeding
institutions.
“Those objectives all fit together,” Bark-
er said. “They are all very important for
the wheat industry as a whole. Developing
sequences is critical to understanding
what breeders have done, and what di-
versity is out there for Canadian varieties
right now.
“While canola is king these days, king
wheat goes way back. Wheat is an essen-
tial crop on the Prairies, and this project
makes sure Canada is a leader, providing
cutting-edge research.”
The project is set to finish in 2016.
FIELD SCHOOL:
A field of spring
wheat that’s used for the University of
Saskatchewan’s wheat breeding program.
Photo: GloriaGingera
Winter
2015
Grains
West
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