Machine learning, drones,
high throughput phenotyping
and field based heat chambers
are some of the innovative
technologies being employed by
Australian researchers and breeders
who are working together to improve
the heat tolerance of wheat.
I think all of us are aware that
the climate is changing, it is
getting warmer, there's no doubt
about it. We're seeing more
heat shocks than we used to see,
much more variable climate,
and I think that's clearly
impacting our crops
and we'll continue to do so into the
future. And our project
has been around finding that
diversity for heat tolerance,
finding it, accumulating
it and giving it to breeders
along with the technologies that
they're going to need to selected
it into commercial cultivars for
grain growers.
GRDC has invested in a
collaborative programme between
University of Sydney, Department
of Primary Industries and Regional
Development Intergrain
and Agriculture Victoria.
One of the major trial sites is at
the Plant Breeding Institute in
Narrabri, where Professor
Richard Trethowan and his team
are working to improve yield
and yield stability in wheat
through better heat tolerance.
We've been using a genomic selection
approach in our pre breeding
program and I think
that was quite farsighted of GRDC to
to fund a program like this.
So we've been able to use that
technology to
combine the genes that we want,
but to also
estimate those breeding values and
recombine in crosses
the best materials based on those
breeding values.
So we've been able to cut the cycle
time down.
So instead of taking
five to six years to produce a line,
we do that in two to three years
now. So it's quite rapid.
And I think what
we have been able to do is,
and I think this is this is
something that a commercial program
might struggle with, we've been able
to traul the world looking
for diversity.
The main idea within the project is
a three tiered phenotyping approach.
So firstly we bring
so many different lines from
all over the world and we look
at them in large scale field trials
here in Narrabri, and then we have
other smaller sites dotted
across Australia and from
the main site here in Narrabri.
We use that to train our algorithms
and then predict what is going to
happen at the other sites across
Australia.
And so the lines that do really well
in those trials end up going into
these heat chambers.
And so the heat chamber's like
bringing the glasshouse to the
field.
There a way for us to be able to
stress the plants in a true
environment so we get a true result
for the growers.
And then from there, the ones that
do well in these heat chambers,
they go into the glasshouse.
So we're able to see more
in-depth research about physiology
and mechanisms behind heat
tolerance.
Look at flowering it causes a
significant damage.
It's probably one of the most
sensitive stages, but
it also causes damage throughout
the grain filling period.
So flowering will affect the total
number of grains that
that are produced.
And of course, that affects yield.
But heat stress during the grain
filling period will affect the
weight of the grain and
that can lead to screenings and
reduced grain weights, lower test
weights.
And from what we've
done, from what we've seen,
it looks like we're dealing with
quite different genetics.
The genetics of tolerance
at flowering to high temperature
is quite different to the genetics
during that grain filling period.
When the trials are so big, so
these are thousands and thousands of
six by two metre plots.
It's really hard for an operator
to go and take measurements
individually for each plot because
the environment is constantly
changing when you're taking those
measurements through the day.
So using drones is a fantastic
way for us to be able to take a
snapshot in time of what is
happening within that field.
And when it comes to heat tolerance,
canopy temperature is really
important. So the drones can come
across, take that snapshot and then
we can pick out on the image which
ones are higher or lower temperature
and then select based on those
results. And there's a list of
things that we do.
So looking at screenings, which
is the amount of small seed that we
have in the harvested sample,
because more small seed means that
the type is less tolerant
to heat. And then things like
thousand kernal of weight, which is
grain size because both,
both grain weight and grain size
are really heavily affected
by heat stress at anthesis, at
flowering and at grain filling.
So being able to separate those
apart and better understand
what mechanisms are at play are real
key reasons why we use phenology and
phenological measurements.
You want to produce a line that has
all this diversity in a good
economic background.
Makes the breeders job a whole lot
easier to transfer that into
a cultivar that has a million grade
that a that can be commercialised.
So that's what we've done.
There's still a lot to do.
What we've discovered is
that there's a lot more
diversity out there.
Um, there's a, there's a lot
more we can do to push
the game further.
We've, we've been able to achieve, I
think, a really significant
intermediate level of heat tolerance
greater than what we see currently
in the commercial sector.
But the evidence suggests that
we can push that even further.