Download Report

Maximising yield
potential in irrigated
faba beans
Wayne Hawthorne
Pulse Australia Industry Development Manager (Southern Region)
Faba beans are a profitable option for growers in both the
Murrumbidgee and Coleambally irrigation areas. Yields of
5 t/ha are achievable and growers have been paid excellent
prices in past seasons. Marketer support is strong for the
current crop with Egypt and the Middle East being the target
markets.
Coming into spring it is important to maximise the yield potential of
your crop through disease control and making sure the first flowers
contribute to the final yield. Early flowers and their pods have the
greatest impact on final yield.
The key actions to maximise yield potential in irrigated faba beans are
to:
QUICK TAKE
›› With good management irrigated faba beans can yield 5.0 t/ha;
and market prospects are strong in Egypt and the Middle East.
›› Monitoring for and protecting the crop against foliar disease is
crucial throughout the whole growing season, and especially
before irrigation or rainfall.
›› New research has shown that having bees located near or
within the faba bean crop at early flowering, aids pollination
and can increase yield by up to 17%.
MM
implement a protectant fungicide strategy
MM
monitor trace elements
MM
consider managed beehives to improve pollination
MM
prepare for harvest and storage.
Disease management
Monitoring for and protecting against foliar disease is crucial, especially
during favourable conditions for disease development. In-crop
humidity after irrigation or rainfall provides ideal conditions for the
spread of foliar disease and so application of protectant fungicide prior
to irrigation or rainfall is recommended.
Chocolate spot and rust are the main foliar diseases to watch out for,
along with ascochyta blight if growing Fiesta, Doza or Cairo varieties.
Early in the season cercospora leaf spot is becoming more prevalent.
The most successful control strategy for disease is prevention, so plan
for at least four fungicide sprays, with seasonal conditions and the
irrigation schedule dictating total spray requirements.
Initial fungicide sprays should have been applied for ascochyta blight
and cercospora control at 5–8 weeks post emergence. The focus in
spring should be on protecting the first flowers, lower leaves and stem
before the canopy closes over.
Next, will be to maintain strategic protection through the flowering
and pod filling stages. Having the lower canopy disease-free initially will
pay dividends later in the season when protective fungicides applied
to new growth may not penetrate into the lower canopy. If the lower
canopy is disease-free then there is less chance of the disease spreading
to top growth.
Monitoring for foliar diseases in spring, centres on the final two stages
of production:
MM
MM
flowering—target chocolate spot, but also consider any rust or
ascochyta protection needs
end of flowering—pods are filling so target chocolate spot and rust
protection. Depending on the variety grown, protection against
ascochyta pod lesions may also be needed. Applications can often
be combined with a native budworm spray.
Four main fungicides, mancozeb, carbendazim, chlorothalonil and
tebuconazole are registered or used under permit for control of
specific foliar diseases in faba beans. Often a mixture is required to
cover all diseases. Total control is based on preventing new infections,
not curing old infections.
Procymidone can be used to provide some minor curative action for
chocolate spot only. It is more commonly used if chocolate spot has
developed more than was expected.
30
IREC Farmers’ Newsletter – Large Area No. 189: Spring 2013
faba beans management
Good coverage of leaves and stems is essential when applying
fungicides, along with the rotation of chemical groups of the fungicides
being used.
When deciding on which fungicide to apply as the final spray of the
season, be aware of withholding periods for grazing and harvesting.
Managing irrigation
Faba beans are actively growing in August and will need water earlier
than winter cereals. The first irrigation should be applied as soon as
water becomes available and should continue as required until near
maturity, when 75% of pods have turned black. Faba beans respond
well to irrigation and can tolerate some waterlogging, but less so
during pod fill. Good drainage is essential for the crop to achieve its
full potential.
Crops planted on beds should be watered and drained within 15
hours while flat-planted crops should be drained within 6–8 hours of
irrigation. Up to four spring irrigations may be required to maintain
adequate moisture. Monitor soil moisture and schedule irrigations to
avoid moisture stress during flowering and pod fill.
Take note of any signs of slow drainage or waterlogging in the fields so
they can be fixed before the next crop of faba beans is planted.
Managing pollination
It now appears that bee and hive management is a practical
and affordable option for pollination in faba beans. Research
published recently in the scientific journal Field Crops Research
has demonstrated a large yield response to honey bees placed
strategically in faba bean crops. A seven-year field study in
South Australia has shown beyond doubt that there is an
economic benefit to using commercial honey bees to increase
pollination and crop yield.
The study measured an average 17% yield response and found
that 90% of the yield benefit consistently occurred in crops
that were within 750 metres of beehives.
An economic analysis has shown that placing hives in groups
through the crop is profitable for both the grower and the
apiarist. A hive density of 1 hive/ha is practical and profitable
and grouping 30 hives together every 300 m, or larger groups
further apart, will achieve a yield response. It is important to
consider the placement of the hives in relation to other crops
such as canola, because the bees will preferentially graze in
canola.
A yield response can be expected in all faba bean growing
localities and will be most noticeable in areas far from wooded
areas, which host a higher population of native pollinators.
It is important to introduce the beehives early in the season,
preferably at the onset of flowering. When bees are active it
is common to see large pods very low on faba bean plants.
Increased seed set through bee activity is well accepted in
horticultural crops and now we know it also occurs in field
crops. These additional and larger pods are a major contributor
to the increased yield.
If bee hives are placed in the faba bean crop, talk with your
apiarist about fungicide and insecticide use. Some products, if
applied at the right time of day, can be used without needing
to shift hives.
The development of chocolate spot should be monitored throughout spring as the
crop goes through the flowering and pod-filling stages. Photo: Wayne Hawthorne
Faba beans respond well to irrigation and can tolerate some waterlogging, but less
so during pod fill. Good drainage is essential for the crop to achieve its full potential.
Photo: Wayne Hawthorne
IREC Farmers’ Newsletter – Large Area No. 189: Spring 2013
An opportunity to achieve substantial yield increases such as
this are rare and well worth investigating.
Recent research in South Australia has demonstrated a large yield
response when honey bees are placed strategically in faba bean crops.
Photo: Danny Le Feuvre
31
faba beans management
Managing nutrients
During crop growth it is worth assessing nodulation on roots. While
nothing can be done for the current crop it will help plan for next year’s
crop if you find nodulation has been variable. If the beans show signs of
yellowing, poor nodulation is a likely reason and this can make the crop
more susceptible to foliar disease.
Trace element deficiency can have a significant impact on yield. In
pre-flowering vegetative stages you can use a tissue test to monitor
trace elements so that any deficiencies can be corrected with foliar
applications as required.
Managing pests
Budworm is a significant pest that can cause significant yield losses
and grain quality downgrades. Monitor for the presence of budworm
in the crop regularly during pod fill. If budworm is found, treat with
a registered pesticide. It may be possible to combine budworm
treatment with fungicide application but do not compromise either
control by delaying one to cater for the other.
Windrowing & crop desiccation
Paddock situations such as a heavy lodged crop, uneven ripening,
weed escapes or to advance harvest date may necessitate windrowing.
The benefits of crop desiccation (crop topping) are similar to those for
windrowing except the crop is left standing, which can be beneficial in
a wet harvest season.
If windrowing or crop desiccation is used as an early harvest or weed
control strategy, correct timing of this operation is critical in faba bean.
Going in too early can have a huge negative impact on yield and
grain quality for marketing. To determine crop physiological maturity,
assessing the colour of the hilum of the grain in the upper-most pods.
The hilum on these seeds should be turning grey-black. At this stage
there will still be green foliage and some lower pods will be turning
black.
Managing harvest & storage
A well-grown crop can give disappointing returns if there are losses
or downgrades due to harvest delays, incorrect harvesting or poor
storage. Harvest should start at 14% grain moisture, at which stage it
can be delivered. Take time to set the header to obtain a clean sample
of whole, undamaged seeds.
Lodging of tall crops can be an issue at harvest, and crops on beds can
be the most difficult to harvest. Harvesting in one direction and slowing
down drum speeds to avoid cracking of the grain can help.
If you plan to store beans on farm make sure they are at less than
14% moisture when they enter storage and keep them out of sunlight
to avoid weather staining. Aeration and cooling helps to slow the
darkening of bean grain in storage, and so helps prolong its storage life
for human consumption markets.
32
Market growth for faba beans is strong and yields of 5.0 t/ha are achievable in
irrigation farming systems in the Murrumbidgee Valley. Photo: Trevor Bray
Boost your knowledge
Pulse Australia provides a best management practice course that covers
the A-to-Z of faba bean production. The course offers participants the
opportunity to engage in open conversation with a range of specialists,
including growers, discussing different management practices suited to
specific areas. A comprehensive reference manual is available only to
workshop participants and provides a source of ongoing support and
information as the season progresses.
This course provides the science and reasoning behind recommended
management practice and an update on the latest research and
advancements in the pulse industry. Courses are conducted in
conjunction with leading faba bean researchers from GRDC-funded
projects in the respective government departments of each state.
Growers and advisors wanting to reserve a place at the 2014 workshops
can contact their Pulse Australia Industry Development Manager
or send an email to [email protected] to express their
interest.
Further information
Wayne Hawthorne
Pulse Australia Industry Development Manager – Southern Region
M: 0429 647 455 E: [email protected]
Gordon Cumming
Pulse Australia Senior Industry Development Manager – Northern Region
M: 0408 923 474
E: [email protected]
Alan Meldrum
Pulse Australia Industry Development Manager – Western Region
M: 0427 384 760
E: [email protected]
IREC Farmers’ Newsletter – Large Area No. 189: Spring 2013