Today we're here in Kingsthorpe,
just west of Toowoomba, looking at a
mungbean crop and how to grow a
mungbean crop in our environment
up here in the northern region.
We'll look at different strategies
today about soil preparation, land
preparation, you're looking at
insects, you're looking at
nutrition, and we're looking at the
harvesting angles.
Yes, we grow them in drylands and
they get really tough times and
people don't like them when they get
halfway up your shins.
But these days, this short rotation
crop of mungbeans is becoming like a
pillar crop, and by pillar crop I
mean that people really set-up
the land preparation and everything
they do just to grow mungbeans.
Let's look at a bit more detail
about how we can grow a successful
mungbean in this northern region.
With me today is Jayne Gentry from
Department of Ag and Fisheries.
Thanks, Paul. And like you said,
setting up the mungbean crop right
from the start is so important.
In the past, I think people have
considered mungbeans to be an
opportunity crop.
It rains, let's stick them in the
ground. But like what we've been
learning and working with the
growers, it's actually
really planning ahead for
your mungbean crop, knowing where
you're going to put them in your
farming system within your rotation.
Never grow mungbeans after mungbeans
and normally don't grow a pulse crop
after a pulse crop.
Mungbeans fit in really well if
you're coming out of that cereal
winter cereal or even summer cereal
crops.
What's your take on the amount of
plant available water we need for
our mungbeans? Well.
I guess in the past we thought
mungbeans didn't actually root very
deep into the soil.
But we've now with current research,
we know that they will actually root
down below 60 centimetres.
We've detected mungbean roots
right down below a metre.
So if they are sourcing water below
that metre, they're also sourcing
nutrients below that metre.
They need water.
We want mungbeans to yield well.
If we're getting yields over 1.25
tonnes, so one and a quarter tonnes
per hectare, you're going to be
needing about 200 millimetres
of plant available water.
So that means going into a paddock,
when you've got a full profile, but
we know mungbeans like rain
in-crop as well.
Jane, we talk about plant available
water and this crop has obviously
had a good amount of water in it
because we tested it beforehand and
we had that 100 to 110 - 120
millimetres of plant available water.
What do you think of the crop now
compared to the water we had?
Well, it's it was set up really,
really well. That's exactly right.
But we had 150 millimetres
of rain about two weeks
ago. And anyone who's growing
mungbeans, we know they like in-crop
rain. They need in-crop rain
to really push those yields beyond
that one into two and above tonnes.
It is really important to soil test
before you put your mungbeans in.
You need to take a soil test right
down to 90 centimetres to a metre
into your soil to understand the
whole spectrum of nutrition
right throughout that profile.
So the sorts of things that you need
to be looking at are nitrogen,
phosphorous, zinc and potassium.
They're probably the four key things
if you're looking at a soil test.
So get in there and soil test before
you plant. Mungbean draws very
heavily on phosphorus and potassium.
We always recommend if you're
planning a mungbean crop, you need
to be putting starter fertiliser
down with that mungbean crop.
Mungbeans are possibly one of the
most finicky plants when it comes
to high levels of sodicity.
So when you're taking your soil
test, consider where those
high levels of sodicity are.
Anything over six per cent
exchangeable sodium percentage
is a problem for mungbeans.
One of the things that we recommend
people doing is doing what we call a
PREDICTA B test.
So this is a PREDICTA B probe.
It actually just as a stomp probe,
that you can actually take a zero to
30 centimetre core out
of your soil.
So the sorts of things that you do
when you do a PREDICTA B analysis
of this soil is you're looking at
some of the main pathogens in our
soil as well as some of the good
guys like AMF.
So the pathogens that we have a look
for in a mungbean crop in nematodes.
So there's two types of nematodes
with the main nematode that is an
issue in mungbeans is
Pratylenchus thornei. So it numbers
high numbers of
Pratylenchus thornei will
significantly reduce
yield in your mungbeans.
We all know mungbeans are
a legume and mungbeans
will nodulate, which means if they
nodulate well, they'll be able to
fix nitrogen from the atmosphere.
But one of the things you need to
consider when you are doing your
soil testing is how much nitrogen
is in your soil.
Because we know and
it doesn't matter what legume you're
talking about, if there is nitrogen
readily available nitrogen in the
soil, the legumes will use that
nitrogen as opposed to
nodulating and fixing nitrogen from
the atmosphere. So if you have
really high levels of concentration
in your soil, the
mungbeans will not modulate.
But that but generally speaking,
we still recommend that
people need to inoculate their
mungbeans.
So one of the best ways to assess
nodulation is get into the paddock
and dig some plants up.
Make sure that you do dig them up
with a shovel, get as much of the
root system as you possibly can.
Washing them will actually just
really carefully remove that dirt.
So you can see here, these plants
actually are not very well
nodulated at all. You can't see very
many obvious nodules.
So we're trying to find the insects,
both beneficials and the
bad guys.
And it's just a simple matter of
taking the beat sheet under the
bottom of the base of the plants and
then using a nice big stick out here
and beating
the mungbean plants quite solidly
to dislodge those insects
onto the yellow beat sheet.
And hey, presto, you've got green
veggie bugs, one of these you've got
a ladybird there which is a good
guy, you've got a
Heliothis Amigera there, which is a
bad guy.
There's a mixture of good and bad,
isn't it? The whole secret is
dislodging those insects from here
onto here. Nice yellow
beat sheet. Easy to count them and
take a note of it.
Make a sum total when you get
out of the paddock.
Hey presto!
Is it a spray decision or not?
It's one of the most difficult
decisions about when to
desiccate your mungbeans.
And for years we had that policy,
the labels were reading 90 per cent
black pod. We know that's way too
late. We wand 90 per cent
physiological maturity of the seed
in the black pod is the thing and
that's usually well in advanced.
Desiccation we're talking about of
course is, you know, killing the
crops so our harvesters can harvest
it successfully.
We know that our mungbean quality
harbours on a good desiccation.
We know that our mungbean quality
harbours on a good harvester set-up.
We don't want green stalks or green
stems or even green parts of the
plant in the header
to muck-up that quality of the
mungbeans we're producing. Desiccation, the
rules are use the right
chemicals, the ones that are
registered, don't go over the
rates, use at the correct time is
another important part and then have
the header properly set-up ready to
go on the edge of the paddock.
So when those beans become nice and
dry, and those stems become nice and
dry. That's when you put the header
in there to get the high quality
mungbeans that our overseas
countries so much want.
We can't produce enough good quality
mungbeans for our customers
overseas. High quality mungbeans.
We got a market for them.
They'll pay for them.
We just got to be able to produce
them all the time.