PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
RESISTANCE.
WHAT IS
RESISTANCE?
RESISTANCE
MANAGEMENT
STRATEGIES
Classification by
Croplife Australia is
according to how a
pesticide kills the
insect, fungus or
weed and is used
for resistance
management.
It does not indicate
toxicity,
that some groups are
more toxic than
others as indicated by
the signal headings
on their labels (see
page 237).
Applications may
fail for reasons
other than
resistance, eg
Incorrect identification
of the pest.
Wrong insecticide may
have been used.
Equipment not
calibrated properly.
Applied at wrong time.
Weather was unsuitable
for application.
Insecticide resistance is the ability of a pest to survive doses of insecticide that
would normally provide control. The pest is not adequately controlled.
At least 50% of world pests have developed some resistance to any one
major group of pesticides. It is so extensive that it is difficult to find effective
chemicals for some pests. Use of the few remaining effective ones has been
restricted in an attempt to prolong their useful life.
Using the same insecticide continually to control the same pest will lead
to the development of resistance by the pest.
In Australia, insects and mites which have developed resistance to a range of
insecticides/miticides include:
Corn earworm (Helicoverpa armigera)
European red mite (Panonychus ulmi)
Green peach aphid (Myzus persicae)
Twospotted mite (Tetranychus urticae)
Western flower thrips (Frankliniella occidentalis)
Use IPM programs which include non-chemical control methods to preserve beneficial
insect and mites. Some insects, eg members of the Order Hymenoptera do not seem to
develop resistance to insecticides. Seek advice about ways of reducing and managing
resistance.
Insecticide Resistance Management Strategies. Commercial crops.
– CropLife Australia has classified insecticides into Insecticide Mode of Action
Groups which indicate the mode of action of the insecticide on a metabolic
process in the pest, ie how it kills or suppresses the pest (page 57, Table 2) .
Some biological insecticides are not classified by CropLife Australia (page 61,
Table 3). Contact Croplife Australia for updates and classification and click on
Resistance Management:
www.croplifeaustralia.org.au/
– To minimize the development of resistance and prolong the life of existing
insecticides, observe 1, 2, 3…. groups on commercial insecticide labels.
Follow resistance warnings. Rotate insecticides between different groups as
recommended. Remember, persons using commercial insecticides must
undergo training. Home garden products available from garden centres
are not required to have insecticide mode of action groups on them.
– CropLife Australia has also prepared management strategies for some pests
and for some crops to minimize the development of resistance.
Pest resistance management strategies developed for some pests include
corn earworm (Helicoverpa armigera), Western flower thrips (WFT)
(Occidentalis frankliniella).
Crop-Pest Resistance Management Strategies have been developed, eg for
cole crops - diamondback moth.
Follow label instructions and warnings. which include resistance
strategies. Application of some insecticides for control of some pests is restricted
in order to prevent or delay the likelihood of resistance developing. “Example”
and “Company” are used in the following general instructions to avoid using
specific insecticide or company names.
GENERAL INSTRUCTIONS
GROUP 4A INSECTICIDE
Insecticide Resistance Strategy
For insecticide resistant management, Example is a group 4A insecticide. Some
naturally occurring insect biotypes resistant to Example and other Group 4A
insecticides may exist through normal genetic variability in any insect population.
The resistant individuals can eventually dominate the insect population if
Example and other Group 4A insecticides are used repeatedly. The effectiveness
of Example on resistant individuals could be significantly reduced. Since
occurrence of resistant individuals is difficult to detect prior to use, Company
accepts no liability for any losses that may result from the failure of Example to
control resistant insects.
Resistance Management Strategies
Strategies are outlined on the label for various pests or crops; there may be
industry management strategies which must be followed. For further information
contact your local supplier, company representative or local agricultural
department agronomist.
56 Insects and allied pests - Integrated pest management