PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
INTEGRATED DISEASE MANAGEMENT (IDM)
MAIN STEPS
IDM is not a specific set
of rules, there is no central
program for everyone
PLAN
PLAN
PLAN
?
X
IDM attempts to manage diseases systematically. The crop is managed as a whole and the
management of diseases is part of producing the crop. IDM maximizes the use of nonchemical
controls and optimizes/minimizes the use of chemical methods while taking
into account all environmental factors, economics, etc, for long term control. May
control diseases more slowly. Training programs are available.
1. Plan well in advance to use an IDM program that fits your situation. Keep records
of the crop, eg source of planting material, planting/sowing dates, temperature,
irrigation, fertilizers and pesticides.
2. Crop, region. List the problems which occur in your crop/region. Check if an IDM
program is available for your crop, eg
Soilborne diseases, eg for clubroot
Crops such as roses, citrus, grapes, vegetables.
The Nursery Industry Accreditation Scheme, Australia (NIASA).
3. Identification. Early detection and accurate diagnosis ensure effective control
measures. This may be difficult and professional advice is often necessary (page xiv).
A good knowledge of the host range, life cycles, types of spores produced,
spread and conditions favouring the disease is necessary. Obtain a fact sheet for each
problem affecting your crop.
4. Monitor early to minimize disease spread, facilitate control by early detection and
determine the effectiveness of earlier control measures. Record findings.
Know when to monitor, eg before sowing, before flowering. Weather warning
systems indicate when some diseases may develop on some crops, eg brown rot of
stone fruits, apple scab, downy and powdery mildews and Botrytis of grapevines, rust
on prunes, eg Prune Rust Infection Prediction (PRIP).
Check where to look, eg leaves, flowers.
Decide what has to be monitored, eg symptoms, presence of spores, soil tests.
Know how to monitor, eg preplant soil tests using a DNA extraction process can
quantify a range of fungal and nematode pathogens from a single soil sample and
predict the likely extent of the losses well before the crop is planted, eg Fusarium,
Rhizoctonia. Results have to be interpreted accurately. Methods include counting leaf
spots, walking the crop in a predetermined pattern, GPS systems.
5. Threshold. Damage thresholds vary with the particular crop and region and may
be determined by legislation. There may be a nil threshold. Otherwise, how much
damage can you accept? Have any thresholds been established?
6. Action/Control. Take preventative measures when possible, eg planting resistant
varieties, appropriate culture. Take appropriate action at the correct time when a
prescribed threshold is reached. There may be legal or organic requirements. Disease
figures may not indicate enough potential damage to warrant action.
For diseases not yet in Australia or in certain states, entry can be prevented
by quarantine measures.
For new arrivals Response Programs control specified disease outbreaks. Noxious
pest/disease legislation and other regulations are most effective during early stages of
invasion. Available disease control methods do not eradicate pests unless they have
been selected for a national or state eradication program.
Most established diseases in Australia can only be contained using appropriate
control methods at the correct time, they cannot be eradicated. Use non-chemical
controls if and when effective. Avoid broad spectrum chemicals.
7. Evaluation. Compare current results with those of previous seasons. Make
improvements if necessary, eg planting disease-tested planting material or resistant
varieties. Monitoring or application methods may need to be improved.
PLAN
PLAN
PLAN
PLAN
CROP
REGION
Each crop has
its own
disease
complex.
List diseases
(and pests
and weeds)
that affect
your crop
IDENTIFY
PROBLEM
Enquiry
Which plant sp.
Examine plant
Check history
References
Expert advice
Diagnosis
Fact sheet for
each problem
MONITOR
When to monitor?
Where to monitor?
What to count, eg
spots, soil tests,
temperature,
moisture?
How to count?
Keep records
THRESHOLD
Economic?
Environmental?
Aesthetic?
Complaints?
Is there a threshold
for this disease
above which
controls must be
implemented?
Is it compulsory?
ACTION
CONTROL
Decision making
?
Legislation
Cultural
Sanitation
Biological
Resistance
Quarantine
Disease-tested
Physical etc
Pesticides
Organic, BMP
Combinations
EVALUATION
Was the IDM
program
successful?
Did you achieve
the control you
wanted?
Can IDM be
improved?
YES/NO?
Fig. 181. Steps in IDM.
Fungal diseases - Integrated disease management 327