PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
Management (IPM)
Some state legislation requires landholders to report the
presence of plague locusts on their land to a designated
authority and to control locusts when the nymphs band
together. Insecticide is provided free of charge and can
be obtained from your local authority office. Advice is
usually available on the state department’s website.
1.Access/prepare a plan. As part of a program of
preventative control the APLC (Australian Plague
Locust Commission) begins treatment when
populations are low and before they reach crops. The aim
ideally is to prevent plagues from occurring. The APLC
engages in operations designed to combat outbreaks,
which in the opinion of the Commission are likely to
result in damage to rural industries in another State.
Protection of crops is not the responsibility of the
Commission although on occasion that may occur as a
consequence of controlling a significant band or swarm
target. In some states, landowner are levied a fee to assist
with locust control.
2.Crop, area, region. Which crop, which State?
Recognize variations. Coastal cities, towns and home
gardens are less vulnerable.
3. Identification. Species must be identified
accurately (Diagnostics page 182) or consult a
diagnostic service (page xiv).
4. Monitor, forecast. The APLC conducts regular
surveys to assess the current size of any concentrated
bands of nymphs (hoppers) and adult swarms and
issues Monthly Locust Bulletins. The printed
version of the Locust Bulletin is produced monthly
during the spring-autumn period and includes a
general summary for each major locust species, details
of known distributions with regional forecasts, and
maps of locust distributions and rainfall events.
– Good records must be kept.
– Forecasting involves actual observation,
monitoring rainfall and weather systems and field
surveillance work (driving around rural areas and
surveying for locusts).
– A Decision Support System (DSS) integrates
large amounts of weather data with locust surveys,
reports and light trap records, to predict where an
increase in locust activity is likely to occur during
favorable weather conditions. Forecasts are
published in the Locust Bulletin:
www.daff.gov.au/animal-plant-health/locusts
5. Threshold. Treatment to protect pasture alone is
not usually warranted unless hopper bands or adult
swarms are causing significant pasture damage and
food for stock is limited. Crops are sprayed only if
there are swarms or hopper bands in the crop causing
significant damage.
6. Action. Action must be coordinated with authorities
before locusts become winged adults if possible, since
hopper bands are denser, easier and cheaper to control
by aerial or ground spraying than swarms. Home
gardeners usually settle on non-chemical methods.
7. Evaluation. Review IPM program to see if it
worked or not. Recommend improvements if required.
Control methods
Legislation. Effective suppression of locusts
can only be achieved by the combined cooperation
of the Australian Plague Locust Commission
(APLC), State/Territory governments, local
councils and private landholders.
www.affa.gov.au/aplc
www.daff.gov.au/animal-plant-health/locusts
The APLC is a highly specialized unit responsible
for the monitoring and forecasting plague locust
populations that pose a major threat to agriculture
it is jointly funded by the Commonwealth, NSW,
Vic, SA and Qld. The APLC is a good example of
how cooperation between the Commonwealth and
State governments can achieve good outcomes.
APLC’s role is to:
– Manage outbreaks of the APL, spur-throated
locust and migratory locust which are considered
an interstate threat.
– Assist States to manage locust outbreaks in their
area of responsibility.
– Seek to improve effectiveness and safety of
locust field operations.
Within a State, APL outbreaks are coordinated
and supervised by Departments of Agriculture/
Primary Industries, through local bodies such as
the Pastures Protection Boards.
Local government may also undertake spraying
operations within their own area.
Landholders. Under provisions of State/
Territory legislation in affected States, landholders
have an obligation to report and control hopper
bands on their properties. Landholders in some
states pay Livestock Health and Pest rates which
contribute to the operations of the APLC.
Grasshopper parasites feed
internally on the locust. The locust
usually dies after the parasite emerges.
Photo NSW Dept of Industry and Investment.
Parasitic nematodes.
PhotoNSW Dept of Industry and Investment.
Grasshopper egg parasite (Scelio sp.).
A small, black wasp burrows through the froth
plug of the locust egg pod soon after it is laid
and deposits a small egg in each locust egg.
Wasp larva feeds on the yolk of the locust egg,
pupates inside the egg, and emerges as a
wasp 1-2 weeks after un-parasitized eggs
have hatched. The parasites are sometimes
abundant and can destroy vast numbers of
locust eggs. Photo NSW Dept of Industry and
Investment.
Biocontrol agent (Metarrhizium sp.)
www.beckerunderwood.com/en/home
Fig. 123. Examples of natural and commercial biological controls.
184 Insects and allied pests - Orthoptera (locusts)