Exam 3 begins here
Recall: Three components interact to produce different biocontrol approaches Emphasize effect of cropping system on NE Cropping System Ideal NE lacks persistence, emphasize introduction Emphasize the NE-Pest Interaction Pest Complex Natural Enemy
Types of Biological Control • Classical – Use of NE taken from native home of a foreign pest. Release once. • Inoculative – Release occasionally. Builds up, controls pest, then dies out & must be re-introduced. • Augmentative – Add to existing population as needed. • Inundative – Flood area with NE. Not persistent. Similar to pesticides. • Competitive Exclusion – Mostly applies to use of hypovirulent pathogen strains out competing virulent strain. • Conservation – Avoid harming existing NE complex. • Suppressive Soils – In some soils, pest (usually a pathogen) does not cause much damage.
BC type and three components Conservation, Suppressive Soils Cropping System Natural Enemy Classical Augmentation Inoculative, Competitive Exclusion Pest Complex
Points on Inoculative vs. Inundative Releases Inoculative Inundative Biocontrol Population Objective Progeny or descendents of released BC BC as released Target Pest Population Future Generations Generation present at release Strategy Preventative Curative
Points on NE Conservation • Judicious pesticide use • Reduce other mortality caused by other management activity • Control secondary enemies • Manipulate host plant attributes • Provide NE’s ecological requirements • Genetic enhancement of NE
Points on Suppressive Soils • Factor responsible often not identified but is biological (lost on sterilization). • Have 3 main effects on plant pathogens – Pathogen may not persist – Pathogen establishes but doesn’t cause disease – Initial disease declines with continued monoculture • Ways to Achieve Suppressive Soils – Soil amendments to alter microbial communities • Green manures for fungal pathogens • Adding chitin for nematode control – Crop rotations/intercropping – Some crops encourage pest-antagonistic microflora.
Biocontrol Conclusion • Read to examples of biocontrols in the text • Evaluation of NE effectiveness – Necessary to use biocontrols in decisions – May be based on: • Statistical correlations from field observations • Numerous types of controlled experimentations – Requires that NE’s be monitored along with pest (cf. spider mite examples cited earlier)
Pesticides
Pesticides • Pesticides Defined: Any substance or mixture of substances, intended for preventing, destroying, or mitigating any pest, or intended for use as a plant growth regulator, defoliant or desiccant. (FIFRA) • Technically includes biocontrols and plants bred for pest resistance. Common usage excludes these.
Pesticide Classification Pesticides are commonly classified several ways: • • Chemical class -- Increasingly diverse Target Organism Mode of Action Application timing or usage
Pesticides Classified by Target Term 1. Algaecide 3. Bactericide Target Algae Term 2. Avicide Target Birds Bacteria 4. Defoliant Crop Foliage 4. Desiccant Crop Plants 5. Fungicide Fungi 6. Herbicide Plants (weeds) 7. Insecticide Insects 8. Miticide Mites 9. Molluscicide Molluscs 10. Nematicide Nematodes 11. Plant Growth Reg. Crop Plants 12. Rodenticide Rodents 13. Piscicide Fish 14. Lampricide Lamprey 15. Wood Preservative Wood Destroying Pests
Target classification may also specify growth stages • Ovicides – Eggs • Larvicides – Larvae • Adulticides -- Adults
Mode of Action Examples • Broad Spectrum -- Kills broad range of pests, usually refers to insecticides, fungicides, and bactericides • Contact Poison -- Kills by contacting pest • Disinfectant (Eradicant) -- Effective against pathogen that has already infected the crop • Germination Inhibitor -- Inhibits germination of weed seeds, fungus spores, bacterial spores. • Nonselective -- Kills broad range of pests and/or crop plants, usually used in reference to herbicides • Nerve Poison -- Interferes with nervous system function • Protectants -- Protects crop if applied before pathogens infect the crop • Repellents -- Repels pest from crop or interferes with pest’s ability to locate crop • Systemic -- Absorbed and translocated throughout the plant to provide protection • Stomach Poison -- Kills after ingestion by an animal
Classification by Timing Annual Crops • Seed Treatment -- Pesticide coats or is absorbed into the seed. • Pre-Plant -- Pesticide applied any time before planting • At-Planting -- Pesticide applied during the planting operation • In-Furrow -- In the planting row, direct contact with crop seed • Side-Dress -- Next to the row, no direct contact with crop seed • Broadcast -- Distributed over the soil surface. • Pre-Emergent -- Before the crop has emerged from the ground • Post-Emergent -- After the crop has emerged from the ground • Lay-By -- Final operation before harvest sequence Perennial Crops • Dormant -- Applied during winter dormancy • Bud Break -- Applied as dormancy is broken Harvest-Related Timing • Pre-Harvest -- Just before crop is harvested • Post-Harvest -- After crop is harvested
Benefits of Pesticides in IPM • • • Inexpensive Greater control confidence Effective and rapid Therapeutic Management efficiency Can enable other management practices
Costs of Pesticides in IPM • Greater human health threat • Greater environmental cost • Detrimental effects on non-target species – Those useful in the CPS – Those useful outside the CPS – Those with no established uses • Interferes with other aspects of IPM – Secondary pests – Re-entry Intervals & scouting – Limits other control options • Less sustainable
Role of Pesticides in IPM • Pest complex – Some require pesticides – Multiple, simultaneous species in same group – At least one species that causes excessive damage at low density – Important species new/poorly understood – Key pest(s) lacking control alternatives – Key pest(s) especially vulnerable to pesticide placement/timing
Pesticide Strategy Vs. Tactic As a group, pesticides may be therapeutic or preventative, broad or narrow spectrum, fast or slow acting, long or short lived, etc. As individuals, each pesticide occupies one point on this multidimensional continuum. The key is to consider each individual pesticide as a separate tactic in an overall IPM plan.
The Selectivity Concept • Key concept in pesticide usage in IPM • Pesticides often classified as “selective” or “non-selective” • Meaning of these terms in common usage is context-dependent (weeds vs. insects) • More formally, there are two types of selectivity – Physiological and Ecological
Physiological Selectivity • Relative toxicity of pesticides under controlled application conditions • Species-specific susceptibility to a pesticide. – Measured as a ratio of LD 50’s of non-target/target species (cf. table handout) – Assumes all individuals & species equally dosed. • Three general methods: – Residues (cf. handout) – Topical application to individuals – Before/after assessment of field populations
Ecological Selectivity • Differential mortality based on pesticide use – Formulation (e. g. granules result in more mortality on soil pests than on foliar NE’s) – Placement (e. g. spot sprays, seed treatments, wicks, in-furrow). – Timing (e. g. pre vs. post-emergent applications, diurnal timing for bees) – Dosage – Reduced dosage usually used in conjunction with one of those above
Uses of Selectivity in IPM • Mammalian toxicity of decreasing significance except in urban/structural IPM • Insecticides – Physiological selectivity favored (target & non-target intermingled) • Herbicides – Historically favored ecological selectivity • Bactericides/Fungicides – Non-selective pesticides usually favored.
Types of Pesticides Your book identifies two kinds (pp. 250 – 257) • Traditional Toxic Chemicals – Inorganic – Organic (Synthetic) • Biopesticides (= Biorational Pesticides) – – Living Systems (Microbial pesticides) Fermentation Products Botanical Pesticides Transgenic (Plant Incorporated Pesticides) – cover under host plant resistance
What are Reduced Risk Pesticides? • Any pesticide that meets any of the following criteria: – – Reduce human health risk Reduce risk to non-target organisms Reduce environmental contamination Enhance IPM adoption • All ingredients of a pesticide must meet these criteria • Can include traditional or biorational • Reduced risk pesticides have greatly reduced regulatory burdens: incentive to manufacturers & farmers
Acres Treated (Thousands) Tons Applied (Thousands) Growth in the use of Reduced Risk Pesticides in California: 1990 - 1998
Pay particular attention to the following sections: An exam question is likely from each of these • Chemical Relationships: pp 262 – 264 • Modes of Action: pp 264 – 266 • Application Technology: 270 – 280 • Pesticide Label: 303 - 306
Pesticide Interactions Book has these three categories, mostly discussed as antagonistic interactions. • Formulation Incompatibility • Altered Crop Tolerance • Alteration of Efficacy
More Thoughts on Interactions • Additive Effects – Most Common: – Different pesticides with the same formulation but targeting different pests. • Synergistic Effects – pesticides used in combination are more effective than when used alone: Two types: – Biochemical – Ecological • Antagonistic Interactions – Formulation–based = “Incompatibility” – Biological = “Pesticide Antagonism”
Resistance, Resurgence, and Replacement Chapter 12 – pp. 314 – 335 Three different ecological responses of pests to pesticides in this chapter: 1. Resistance – Pest susceptibility to pesticide decreases over time. 2. Resurgence – Pest population increases dramatically following pesticide 3. Replacement – One pest is replaced by another. We’ll take them in reverse order
Pest Replacement • Mostly a problem with arthropods and weeds – Tends to be more reversible with arthropods • Note Fig. 12 -7
Read Chapter 17 by Next Wednesday Host-Plant Resistance and Other Genetic Manipulations of Crops and Pests pp. 443 – 469 Do not confuse plant resistance to pests with pest resistance to pesticides. They are different.
Resurgence • Mostly documented with insect pests • Mostly associated with indirect, secondary/minor pests for several reasons. – Key pests are watched too closely to resurge – Direct pests are mainly late-season pests & there isn’t time to resurge – Pest must be held at least partially in check by some agent that is affected by the pesticide • Note Fig. 12 -6 in book.
Pest Resurgence Pest (8) Natural Enemy
Pest Resurgence Pest Natural Enemy
Pest Resurgence pest
Pest Resurgence Note: 14 pests/leaf
Four processes contribute to resurgence 1. Reduced Biological Control (Secondary) – most common with insects 2. Reduced Competition – most common with weeds (mono vs. dicots) 3. Direct Stimulation of Pest – usually due to sub-acute doses 4. Improved Crop Growth
Resistance • Mostly a problem with pesticides (so far) but applies to all management tactics. Ex: – Biological Control – Rabbits & virus, Bt – Cultural Control – corn rootworms & rotation – Host Plant Resistance – many examples • Most serious, general problem in IPM • Arises because all management actions are selection pressures • Problem is rapidly getting worse
Read about Kentucky’s Herbicide Resistant Weeds Here
Resistance is best understood as a process Initially, a small proportion of population has a resistant mechanism by chance.
The Resistance Process These individuals survive at a higher rate than others
Resistance as a process Resistant individuals increase in frequency
Resistance as a process Eventually, the pesticide or other management tactic causes too little control to be effective.
The process has three general stages, each with its own Management Strategy Man age or R eve rse Abandon Pesticide/Management Tactic Prevention Need to monitor resistance
Impact of Resistance • Overall agricultural productivity (during build phase) – Increased pesticide usage – Increased damage • Environmental impact – Increased pesticide usage – Increased use of non-renewable resources – Increased acreage • Pest management flexibility – Loss of pesticide tactic – Constraint on new pesticides
Causes of Resistance Independent of Pesticide 1. Genetic Factors 2. Ecological Factors 3. Severity of Selective Pressure
1. Genetic Causes of Resistance • Genetic Factors – Relative dominance – More dominant is bad – Linkage to phenotype – Fewer genes is bad – Initial resistant pop – Prior exposure – Broad diversity & diversity-maintenance • Low diversity associated with foreign pests • Sexual reproduction • Haplo-diploidy
2. Ecological Causes of Resistance • Population Isolation – More isolated develop resistance more rapidly – Less isolated allow resistance to spread more rapidly – Narrow host range – more selective pressure • Intrinsic population factors – – Voltinism Generation time Fecundity Behavioral factors
3. Selection Pressure • Selective pressure is “high” if a “low” percentage of susceptibles survive to reproduce – Reduce pressure by: (1) reduce dosage & (2) reduce frequency • Site of action – Alternating modes of action reduces pressure • Spatial coverage – reduce pressure by reducing coverage • Timing – Using pesticides after reproduction reduces selective pressure
Resistance Categories • Resistance to individual pesticides 1. 2. 3. 4. • Delayed entrance of toxicant Increased deactivation/decreased activation Decreased sensitivity Behavioral avoidance Resistance to multiple pesticides 1. Cross-resistance & class resistance 2. Multiple resistance 3. Multiplicate resistance
Resistance Management • Strategy – Saturation – Moderation – Multiple Attack • Tactics – Prevention – Reversal
Specific Tactics • Prevention – Use pesticides only as needed – Time/target applications precisely – Combine chemical & non-chemical controls • Reversal – Cease use of pesticide causing resistance. Problems • Probably the preferred control • May be used for other pests • Area-wide enforcement usually necessary – Refugia – Use synergists – Genetically manipulate the pest population (Gene Driving)
Final Note • All management tactics are susceptible to resistance • Resistance best managed preventatively • Pest management needs to pay more attention to resistance management • Resistance management will become a greater part of pest management over the coming years
Host Plant Resistance in IPM Your book uses the following approach 1. Host Plant Resistance (HPR) – General Concepts 2. Conventional Plant Breeding 3. Genetic Engineering 4. Application of Pest Genetics in IPM Our lecture will mostly concern additional material
HPR Defined Any heritable characteristic that lessens the effect of pest attack. • Genetic – crop and pest • Organismal – concerned with “effect” – Biological plant-pest interactions – Economic Damage • System – Traits may or may not be acceptable in a given CPS – Preference-based traits – Conflicting traits • Create other pest problems • Conflict with crop production/use/marketing
Characteristics of the Pest Complex • Damage Concentration – Complex with most damage confined to a few pest species is a good candidate for HPR • Identifiable plant-pest dependency • No conflicting pests • Few direct pests (HPR will likely make product less usable)
Advantages/Disadvantages of HPR • Advantages: See list pp: 444 – 445 • Disadvantages – Time required – Genetic Limitations – Pest Biotypes/Races – Conflicting Agronomic/Marketing Traits – Conflicting Pest Management Traits
HPR as an observed outcome Environmental Effects Abiotic Genetics This is what we actually see Biotic Management Other Pests Cultivar Pest Yield Injury or Density Genetics
HPR and the Injury Scale • “True” Resistance – – – Immunity – often restricted to a specific race Highly Resistant – Relatively little injury Low-Level Resistance – Less injury than avg. Susceptible – About average injury Highly Susceptible -- More than average • “Partial Resistance” – High & low-level • Note – “Susceptible” does not mean “defenseless”, means average injury. Changes with change in prevailing cultivars.
HPR and the Yield Scale • “Tolerance” – Highly, Moderately Tolerant; Intolerant, Highly Intolerant • Creates two problems 1. Pest builds up & may cause other problems 2. Affected by many other factors (e. g. soil, nutrition, other pests) but the net effect can’t be measured until harvest.
Apparent Resistance • Evasion – Breaks synchrony between pest and crop • Escape – Plant not attacked by pest for reasons other than the plant. E. g. – By chance – Geographical/meteorological barriers • These complicate resistance assessment
Factors that affect resistance expression • Physical Factors • Plant Nutrition • Biotic Factors – Plant factors – Pest factors • Biotype • Initial infestation level
HPR as a response by the pest • Antixenosis (non-preference) -- prevents pest from commencing attack. Two types – Chemical – Allelochemicals are chemicals produced by one species (plant) to affect another species (pest). – Morphological – can be very long lasting. • Antibiosis – Interferes with pest attack once it begins. – Pest has reduced survival, fecundity, reproduction, etc. – Two types • Primary metabolite missing • Toxin
HPR as a phenotype category • Constitutive – prepares defense as plant grows – Often associated with yield drag • Plants always commit a portion of photosynthate to defense • All target tissues must be defended – Several advantages: • Young plants can be screened • Easier to assay • More dependable • Induced – defense prepared when attack comes – Localized – Hypersensitivity mostly with pathogens – Systemically Acquired Resistance (SAR) – Both have time lags & can be overwhelmed by large initial pest population
Genetic Basis of HPR • Better understood for pathogens – Fewer control options – Effect of races more pronounced – Closer genetic association between pathogens & plants • Horizontal vs. Vertical Resistance – Vertical – based on one gene, “gene for gene hypothesis” – Horizontal – based on >1 gene, “general resistance”
Vertical – “All or None”
Horizontal Resistance – Graded with Rank Order
Vertical vs. Horizontal Resistance in IPM • Vertical’s advantages over horizontal – Amenable to simple, qualitative scouting methods – Easier to develop & manipulate – Effectively resists initial attack vs. changing the rate of increase after attack • Vertical’s disadvantages relative to horizontal – May be too specific (single race) – May be overcome by pest more easily, this can happen quickly • From the pest’s perspective, these are phenotypes – Multiple vertical genes can be combined to give a synthetic horizontal cultivar: “Multilines” – A single trait that is polygenetically determined may be overcome as easily as a monogenetic one.
Sources of Resistant Genes • Wild plants – Most wild plants’ genetic systems are not well studied • Germplasm collections • Primitive (heirloom) cultivars – Developed in thousands of years of selection • Tissue culture – Captures somatal mutations • Induced mutations – Limited success • Microbial sources – Rapid and straightforward – Preserves other agronomic traits
Gene Deployment Strategies Objective of GDS is to prevent pest from overcoming the HPR mechanism • Sequential Release (Replacement) – most common, least effective, several problems • Cultivar rotation • Geographic spacing – older technique • Mosaic planting (some fields planted in one variety, other fields in other varieties) • Mixing cultivars in the same field. Two ways of doing this: – Multilines -- mixtures of lines bred for phenotypic uniformity of agronomic traits – Mixtures -- mixtures of agronomically compatible cultivars with no additional breeding for phenotypic uniformity • Pyramiding/Stacking – May be the best approach when applicable • Refugia
Special Case: Bt Crops Read this article for background Toxic Crystal Phase contrast of Bacillus thuringiensis. The vegetative cells contain endospores (phase bright) and crystals of an insecticidal protein toxin (delta endotoxin). Most cells have lysed and released the spores and toxin crystals (the structures with a bipyramidal shape)
BT Mode of Action 1. Caterpillar consumes foliage with the protoxin and/or spore 2. Toxin activated by gut p. H, binds to gut wall membrane, caterpillar stops feeding (minutes) 3. Gut wall breaks down, microflora invade body cavity, toxin disolves (hours) 4. Caterpillar dies from septicemia (1 – 2 days)
Different Bt strains produce different versions of protoxin Group Cry I Size (k. Da) Pest Controlled Bipyramidal 130 – 138 Lep larvae Shape Cry II Cuboidal 69 – 71 Leps & Flies Cry III Flat Irregular 73 – 74 Beetles Cry IV Bipyramidal 73 – 134 Flies Cry V-IX Various 35 – 129 Various
Special Case: Herbicide Resistant Crops
Bt and Herbicide Resistant Crop Prevalence in the US, 2000
Herbicide Resistant & Bt Crops Created the Same Way
Benefits/Concerns Over HRC • Benefits – Simplifies weed management – Speeds adoption of reduced tillage systems – Overall reduction in pest losses • Concerns – – Will eventually create herbicide-resistant weeds Unknown pleiotropic effects Regulatory/marketing issues Over-reliance on them will prematurely end their usefulness
Using HPR in IPM • As a stand-alone tactic – Objective is to preserve the resistance; emphasis on deployment strategy • Integrated with other tactics – Crop rotation: if HRC’s are used, must rotate both for pest and herbicide type. – Pesticides: Emphasize measures to prevent pesticide resistance (lower doses, frequency) – Biological control: Conflicts do occur – Action Thresholds: Whenever there is significant, cultivar-specific variation in yield response to a pest, action thresholds should be re-examined
Behavioral Control • Your Text Follows This Outline: – Vision-based tactics – Auditory-based tactics – Olfaction-based tactics – Food-based tactics • Lecture Will Follow This Outline – Behavior modifiers – Mating disruption – Genetic manipulations
Behavior Modifiers Most insect behavior modifiers are chemical • Semiochemicals – Facilitate communication between individuals – Pheromones: within a species – Allelochemicals: Between species • Allomones: Producer benefits, receiver does not • Kairomones: Receiver benefits, producer does not See book discussion, pp: 379 – 382. Pay particular attention to the pheromone types.
Pheromone Usage • Sex pheromones most widely used in IPM • Relatively simple chemistry enables synthetic versions. • Three main uses in IPM: – Monitoring one sex – Mass trapping sexually active adults – Interfering with mating • A few “Anti-pheromones” are now available. Future use unknown. Here’s an example.
Pheromone Disperser Examples Plastic Spiral Card style Rubber septum (with holder) Cable/Twist Tie
Kairomone Usage • Most are attractants used as baits to attract pests to traps or bait stations. Examples: – Curbitacin & cucumber beetles – CO 2 and mosquitoes – Protein hydrolysates and fruit flies • Normally attract both males & females • “Attracticide” – lure mixed with toxin
Allomone Usage • Mostly used as repellents – DEET – Neem extracts • Many are experimental & their use is still only a promise – Plant attractants for biocontrol agents – Feeding deterrents • All have short residual activities
Mating Disruption • Floods area with sex pheromones (cf. Fig. 14 -6, p. 387). Also known as “pheromone inundation” & “air permeation” • Application may be via recoverable or nonrecoverable methods • Problem: Sex pheromones mostly used with species that have high mobility. – Requires large area coordination – Many site-based characteristics affect result
Genetic Controls 1. 2. 3. 4. Four categories Sterilization – Mass release of sterilized individuals Conditional Lethal Releases – Released individuals carry lethal genes Hybrid sterility – Progeny will be nonviable Other – To be developed
1. Sterile Insect Technique (SIT) • Steps: 1. Mass rear pest, 2. Sterilize males, 3. Flood area with these males, 4. Females will mostly mate with sterile males • Uses one of two sterilization techniques – Nuclear – Chemical • Many successes • Most famous application was the screwworm eradication.
Progression of Screwworm Eradication
Requirements for SIT • • Works best on population with low fecundity Five Conditions 1. 2. 3. 4. 5. Must be able to treat entire population Sterilization cannot debilitate males Releases must mix sterile males well Females should only mate once Must sustain high ratio of sterile: wild males
2. Conditional Lethal Release • Release individuals that have a gene that proves fatal under specific conditions • Main paper here • Advantages over SIT – Can release both males & females – May require fewer released individuals – Can insert a wide variety of genes • Disadvantage: Requires several pest generations before “lethal condition”
3. Hybrid Sterility • Males & Females of different strains can produce non-viable offspring • Incompatible strains can be generated through several ways – Direct genetic manipulation (“Transposable Elements”) – Microbially-mediated (Cytoplasmic Incompatibility)
Example: Wolbachia in lower flies
Physical & Mechanical Tactics Main Categories • Environmental Modification • Physical Exclusion • Direct control of pest individuals These tend to be used in special situations such as structural IPM or with special types of pests such as vertebrates.
Environmental Modifications in Structures • Eliminate conditions conducive to a pest infestation will reduce pest attractions to a particular area. • These include: – – – Removing the breeding source if possible, Eliminating moisture conditions, Eliminating harborages, Cutting back shrubs and tree limbs next to buildings, Using proper lighting (light management) to draw night flying insects away from the property.
Environmental Modification Categories • Temperature – often used for stored products Flame weeders – Heat – Cold • Water – Flooding – Dessication – Very important in greenhouses – Irrigation • Light – Mulches (two kinds) Organic mulches were recently living tissue Inorganic mulches were never living. Gravel, rock, plastic, landscape fabric, etc.
Exclusion – Used 4 Ways Note: Exclusion is very often associated with structural pest management 1. Used to keep pests from entering an area or building 2. Limit movement within an area 3. Isolating a recurring pest problem (e. g. entrance or doorway) 4. Isolating a highly sensitive area (e. g. operating room).
Exclusion in Structures • Doors fit & seal, windows screened, both kept shut. • Caulking & other sealants used at: – Utility entrances (plumbing, electrical, sewer) – Exterior (wood trim, brick mortar, foundation cracks & crevices). • Isolation of deliveries & waste.
Birds in structures are often managed via exclusion
Physical Exclusion in Fields • Barriers: Effectiveness varies by pest – – Mollusks Arthropods Birds Mammals • Traps – Weeds – Arthropods – Vertebrates
Barrier Examples Netting and screens are often used as an insect barrier Slugs won’t cross copper Floating row covers on cabbage protecting against cabbage butterflies
Trap Examples -- Click on picture for more detail Slug trap Numerous live traps for vertebrates can be found here Pathogen trap for use in greenhouses or irrigation water
Physical Controls in Structures Using energy factors in the environment such as heat, cold, light, sound, x-rays, infrared rays, etc. , to kill pests or attract them to a killing mechanism • Thermal Controls (heat and cold treatment) • Electrocution (zappers) • Microwave suspect materials
Direct Control Removing pests by hand or using mechanical devices to trap, kill, or keep out individuals • Hand picking, killing individually • Some Traps • Vacuums • Hoeing • Shooting -- Most effective when limited to females.
Hand Picking Examples Slug Picker Arthropod Vacuum Swatter
Other Direct Control Examples Tractor-mounted field vacuum for vacuuming arthropods. Note: this vacuums all arthropods, good & bad. Direct control through shooting has become a specialized sport – Varmint Hunting, with specialized equipment emphasizing small caliber, long range and high velocity.
In Structures, Direct Control Using Traps Often Relies on Effective Trap Placement • Place close to walls, behind objects in dark corners, wherever pest activity seen. • Place them so that pests following normal travel (usually close to a wall) will pass directly over the trigger. • Leave traps untriggered until the bait has been taken at least once prevents rats or mice becoming trap-shy. • Baits compete with other food sources.
Problems with Physical and Mechanical Control • Generally more practical in small areas than large ones. • Labor intensive • Cumbersome (e. g. must remember where traps are located & service them) • Inefficient (removes only a small portion of pest population) • Often viewed as inhumane • Many of these tactics (e. g. traps) are more useful as a monitoring procedure.
Comparison of Physical & Mechanical Methods Method Exclusion Control Monitoring Control Type Effectiveness High Preventative None Habitat & Behav. Mod High Preventative & Curative None Physical Control Moderate Curative Moderate Mechanical Control Low Curative High
Pest Invasions and Legislative Prevention • • • The main sections of this chapter Invasion and introduction mechanisms Regulatory premise Pest risk assessment Exclusion & early detection Containment, control, eradication
Invasion Mechanisms -- Intentional • • New crop plants New ornamental plants New animal food sources Erosion control Biological control Misguided or lack of knowledge Discarding unwanted organisms Malicious intent
Invasion Mechanisms -- Accidental • • • Produce or human food Contaminant of crop seeds/planting stock Contaminant of feed for animals On or in live animals Contaminated soil Irrigation water Transportation vehicles Farm machinery Military activity
Basic Concepts of Regulatory Control • Main premise – All of the previous mechanisms are a result of human behavior. Laws modify that. • It is almost all preventative • Regulatory Control Defined: All forms of legislation and regulation that may prevent the establishment or slow the spread of a pest population.
Regulated Pests • “Regulated Pest” – One official control and thus specifically identified, in laws or in regulations, whose establishment, propagation, or movement is facilitated by human actions which are therefore prohibited or outlawed. • Two Kinds of Regulated Pests 1. Quarantine Pest – Not present in the regulated area 2. Regulated Non-Quarantine Pest – One whose presence/occurrence is regulated.
Quarantine Pest Vs the Regulated Non-Quarantine Pest • QP is controlled only via quarantine, RNQP may be controlled in any manner • QP is absent, focus is on preventing entry; RNQP is present, focus on other objectives • Economic impact of QP unknown; RNQP has a known economic impact • For QP, object of control is anything; RNQP it is mainly hosts, host production, storage/shipping, or pests themselves.
Major Laws • Emphasize the regulations & laws sections on pp. 230 – 232. Be especially familiar with federal laws (pp. 231 – 232) • State Regulations are often modeled after generic versions by the National Plant Board • Example of a state quarantine: Sudden Oak Death in Kentucky
Regulatory Tactics – 4 Categories 1. Prevention of Entry 2. Eradication – 2 steps – Domestic Quarantine – Eradication 3. Retardation – Often used when eradication fails 4. Mitigation of Losses
Quarantine as a Regulatory Technique • Inspections – Intensity of inspection dictated by level of Pest Risk (cf. pp 232 – 233) – – Point-of-Origin (Phytosanitary Certificate) Point-of-Entry Field Inspections Regional Inspections & Surveys • Quarantine Effectiveness – considered a temporary control – Eradication planning is always part of a quarantine
Quarantine continued • • Quarantine Costs: Inspection, compliance, eradication Quarantine Value – – – • Buy time for eradication/control development Keep initial pest populations small Restricts biotypes of initial populations Responses to intercepted pests – Costs borne by owner – – Goods returned Goods destroyed Goods may be held in isolation for confirmation Goods may be treated (usually fumigation)
Quarantine Examples • Citrus Canker in Florida – Spatio-temporal map shows the quarantine is a losing battle • Golden Nematode in NY – Quarantined successfully since before WWII • Mediterranean Fruit Fly – On-going battle
Eradication • May be primary or secondary to quarantine – Secondary to Quarantine. Eradication backs up a quarantine. Requires; • • • Pest detection at low levels Ability to mobilize quickly Controls must be effective & used excessively Reintroduction is barred Example – Mediterranean Fruit Fly
Primary Eradication • Quarantine backs up eradication effort – Target is already well established (or native) – Quarantine is always domestic, often multiple simultaneous quarantines (different jurisdictions) – Must be able to establish a “moving quarantine” – Must be able to tell with certainty when a pest has been eradicated from an area
Eradication Pros • Once the pest is gone, no more costs • Long term avoidance of adverse effects of pest management actions • Eradication of a key pest may also eliminate other pests (e. g. secondary pests) • Eradication of key pests makes non-chemical control of other pests more feasible • New technologies make eradication more feasible
Eradication Cons • Low chance of success, most successes have been with eradication as secondary to quarantine • Incurs exceptionally high environmental impact • Removal of a pest has unpredictable impact on system
Additional Regulatory Tools • Control Districts • Enforced Crop Production Rules • Licensing and Certification • GMO-related
Control Districts A jurisdictional area such as a county or group of counties, specifically identified as a district in which the presence of a certain pest is prohibited or controlled through a public agency. Most common types: • Plant control – landowners responsible for control & subject to fine. • Mosquito – Public agency has the right to implement control on private land
Enforced Crop Production Rules IPM techniques is that are required by statute or ordinance, imposed on all growers in a given area, and enforced, usually by penalty. Major types: • Crop or Host-Free Periods • Planting Date Restrictions • Cultivar Restrictions • Compulsory Sanitation Measures
Licensing and Certification Ensures that infested or contaminated material is not transported, sold commercially, or used as breeding stock. • Seed & Stock Certification (domestic) • Certification for Export Markets
GMO-Related Regulation Crop Production Crop Use • FDA, EPA & USDA are principal GMO regulatory bodies in the US – FDA: Regulates food crops if they contain • Something new to the human diet • Something that warrants suspicion (e. g. a toxin) – EPA: Regulates crops containing pesticides – USDA mostly regulate crop development, testing, and release. If crop contains pesticides, USDA & EPA jointly regulate.
IPM Implementation • Chapter 19 – Societal and Environmental Limitations to IPM Tactics – Societal constraints and public attitudes – Environmental issues • Chapter 18 – IPM Programs: Development and Implementation • Chapter 20 – IPM into the Future
Societal Limitations • Society places limits on pest management techniques because of risk perception • Limits often increase producer costs • Society must reimburse producers or must export risks to other societies • If producers are reimbursed, they will adopt IPM • How much is society willing to pay for IPM? See fs 897
If Society is willing to pay more, farmers will provide IPM products IPM-Labeled Sweet Corn in NY. Labeling is by “Elements. ” Source: http: //www. nysipm. cornell. edu/labeling/label 2. html
Many think that the key is in IPM Labeling and Marketing • Labeling on a large scale began in NY. • National effort is now underway through the IPM Institute – Set Standards – Certification Program
IPM Programs: Development and Implementation • IPM Revisited • IPM Program Development • IPM Program Implementation • Examples of programs will be presented over the four subsequent lectures.
Point of IPM Programs: Adoption Factors affecting IPM Adoption • • • Expected profitability Risk Required skill level or education Scale or size of farm Alternative or competing technologies Enterprise specialization Information sources Credit availability (if substantial expenses involved) Tenure or farmer’s experience Environmental/regulatory policies
Example: Size or Scale of farm Source: http: //www. aftresearch. org/ipm/symposium/26
Size of Farm Continued: Insecticide Use by MA Apple Growers, 1995
Adoption factors vary by crop and rationale Bedding Plants Potato Strawberry Sweet Corn Avg Technique is too costly 20 % 22 % 15 % 17 % 19 % Uncertain about effectiveness 34 % 36 % 40 % 44 % 31 % Don't know exactly how to use 33 % 19 % 41 % 34 % 32 % Satisfied with current methods 55% 60 % 43 % 51 % 52 % Reason Sourece: http: //www. umass. edu/umext/ipm_projects/education/assessing_grower_adoption. html
IPM is Implemented by the IPM Program • IPM Program defined: (1) An organization dedicated to implementing IPM in a specific crop or set of crops; (2) The collective activities of such an organization. • “Collective Activities” include: – Developing strategies – Education of various individuals – Assisting in implementing specific aspects of IPM (e. g. monitoring efforts) – Providing specific IPM-related services (e. g. forecasting) – Conducting any IPM-related research or demonstration – Other activities (e. g. certification & testing)
IPM Program Components • Pest Identification • Management strategy couched in the crop context • Pest monitoring • Decision criteria for selecting tactics • Record keeping • Evaluation of tactics (post treatment), strategies, and overall program
Programs themselves are highly specific • See Program examples on pp. 484 – 493 • Lessons learned from the term paper • Review the KY IPM program website • For class on Monday: – Review blue books – Come prepared to participate in discussion of the KY IPM Program
Скачать презентацию Exam 3 begins here Recall Three components
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