integrated pest management (ipm) concepts and grower training needs in hawaii’s tropical fruit...
TRANSCRIPT
Integrated Pest Management (IPM) concepts and grower training needs in Hawaii’s
tropical fruit industry
Is IPM a sustainable approach to managing pests?[Sustainable: “method of using a resource so that the resource
is not depleted or permanently damaged”]
Pest Control – often creates its own problems – can lead to permanent “damage”.
Pest Management vs. Pest Control
• Pest management aims to maintain insect populations below a threshold;
• Emphasis is not on eradication.
The UH IPM Verification Program
IPM Implementation on 75% of Hawaii's Crop Acres by the Year 2001. Our highest priority is implementation to meet President Clinton’s goal for IPM implementation on 75% of the nations crop acres.
http://www.extento.hawaii.edu/IPM/
Verification is based on points allocated for:
• Development and implementation of IPM procedures;
• Monitoring, application of various options, justification for each action.
• Farmer provides documentation for annual audit.
Insects – prevalent features of our environment
• Number of species;
• Interactions in
ecosystems and
with us;
• Our major competitors.
Understanding insect numbers
• May be explosive outbreaks
• Seasonal changes in numbers;
• What are the causes of changes in abundance?
• Insect ecology examines dynamics of insect numbers temporally and spatially;
• Phenology and diversity are also important;
• Interactions with plants and other insects.
• Ecology aims to explain how environment (biotic and physical) affects abundance, phenology and diversity of insects;
• Therefore ecology forms the basis for pest management.
• Understand both ecology and economy to implement IPM
Some history: Dealing with pests
• Pre-insecticide era: 2500 B.C.: Sulfur, herbs and oils used to protect seeds and stored grain.
• 300 B.C.: Plant phenology recognized as a means of avoiding pests; Chinese started using natural enemies of insects.
• By 1101, Chinese used soaps to control pests;
• Late 1600’s: tobacco infusions , arsenic used.
• 1700’s: Importance of temperature summation in determining insect phenology discovered!
Plant resistance used in the USA;
Botanical insecticides rediscovered.
• 1800’s: inspection and quarantine became important;
• 1920 - 1930’s: Depended on crop sanitation, timing of planting, minor use of insecticides.
• Insecticide era: ~1939 - 1962: DDT was discovered; Organophosphates later.
• Purely insecticide-based approach to pest problems emerged.
• 1962: Silent Spring by Rachel Carson
• The concept of Integrated Pest Management was developed.
• Emphasized the selective use of insecticides, and conservation of natural enemies.
Emphasis shifted from control to management.
Tolerance, rather than decimation encouraged.
Elements of IPM:
• Multiple tactics used in a compatible manner;
• Pest numbers below levels that cause economic damage;
• Consideration of environmental impact.
Aims of IPM:
• Reduce pest populations to levels below those causing economic impact, using multiple, compatible techniques;
• Reduce environmental impact of pest management.
Economic decision levels - thresholds
• Usually expressed as number of insects per area, plant, or sampling procedure
• Sometimes use extent of plant damage
• Include biological and economic information
Gain threshold
• Expresses the beginning point of economic damage.
• Insecticide application would have to save 5 bushels per acre to be profitable
ueMarket val
costs Management holdGain thres =
acreper bushels 5 bushel / $2
acre / $10 GT ==
Economic threshold
• Also called Action Threshold – Insect density that would justify intervention
• May be a fixed economic threshold: e.g. if EIL is 6 insects per plant, intervene at 4 insects per plant;
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Economic loss
No loss
Non-economic loss
Time
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Economic injury level:
Economic threshold
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Time
IPM Options:
• Biological control
• Physical control
• Cultural control
• Chemical control
Monitoring insect numbers is the cornerstone
of IPM
Approaches to monitoring:
Various methods:
• Direct counts
• Traps
• Damage estimates
• Prediction: degree-days
Benefits of monitoring:
• Track numbers of pests and natural enemies;
• Able to target insecticide applications at the correct time;
• Enhances conservation of natural enemies;
• Indicate efficacy of treatments.
Biological control:• Natural enemies of pests cause mortality;• Can maintain pest population at below-threshold levels
Predators
Parasitoids
Pathogens
Types of BC:
• Import natural enemies - establish in field - Classical BC;
• Augmentative releases: inundative or inoculative releases each season;
• “Conservation” BC: depend upon local natural enemies.
• All these approaches require conservation of natural enemies to be effective.
Conserving natural enemies
Reduce insecticide use;
Use softer chemicals;
Manipulate habitats, e.g. intercropping.
Concerns: Biological Control
• Non-target effects?
• “Necessary evils: murder, drugs and biological control” (Lockwood 1999)
• Host specificity testing
• Risk assessment protocols?
Insecticides
• Insecticides as resources:
Huge financial investment for development;
Potential for Use or Abuse of this resource;
Can play an important role in providing options for pest management.
Problems with insecticides:
• Kill or disrupt natural enemies
• Secondary pests
• Residues on produce
• Build-up of resistance – insecticide “treadmill”
• Environmental concerns
Dealing with resistance
Wrong approach:• Raised concentrations of active ingredients!• Increased frequency of application!
Correct approach:• Reduce reliance on chemicals.• Alternation of chemical groups.• Targeted insecticide applications.
Benefits of insecticides:
• Can be effective if used correctly• Can provide an immediate solution• New formulations are safer • Target-specific modes of action are being
developed• Effective chemicals should be conserved as a
component of sustainable pest management programs.
Summary
• IPM requires pest and beneficial insect identification;
• Need effective means of managing these;
• Require economic information;
• Require training to encourage adoption.
Are fruit growers interested in IPM training and verification?
• What are the needs of growers in terms of training?
• Would verification be valuable to you?
• Should we proceed to develop verification guidelines?
Mark G. Wright
Department of Plant & Environmental Protection Sciences, CTAHR, UHM
Tel: 808 956-7670
Email: [email protected]
Website: http://www.ctahr.hawaii.edu/wrightm