9 9 • INSECT PEST MANAGEMENT FOR COMMERCIAL VEGETABLE CROPS
Organic Approaches to Insect Pest Management on Vegetable Crops · 2019. 3. 27. · Insect Pest...
Transcript of Organic Approaches to Insect Pest Management on Vegetable Crops · 2019. 3. 27. · Insect Pest...
Organic Approaches to Insect Pest Management
on Vegetable Crops
Celeste WeltyExtension Entomologist
March 2019
Chr
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The goal
The reality
Search for a weak link in life cycle
Ecological contextThe crop field:• Crops• Pests• Natural enemiesThe agricultural
landscape:• Crop fields• Woodlands• Hedgerows• Ditches
Crop ecology: is food chain balanced or unbalanced?
producer (mustard)
herbivore (imported cabbage-
worm)
herbivore (cabbage maggot)
carnivores (parasitoid
wasps)
Pest management actions• Strategies–Do nothing–Eradication–Prevention –Suppression
• Tactics–Cultural–Mechanical–Biological–Behavioral–Microbial–Chemical
Issues of scale• Large farms vs small farms vs gardens• Monoculture vs polyculture
• Same crop• Same possible pests
• Different intensity of infestation• Different tactics• Different economics
Organic vs other approaches• Willingness to use tactics:–More knowledge intensive –More labor intensive –More expensive (?)– Include chemicals: yes or no?
• More concern with restoring checks & balances• More willing to tolerate damage
Biological Control• Control of pest by other
organisms that act as natural enemies–Conservation–Augmentation
• Common natural enemies–Predators–Parasitoids
Biological Control:Predators
• Develop at expense of more than one prey item• Predator often larger
than prey• Prey usually killed &
consumed quickly
Predatory Beetles
• Lady beetles
• Ground beetles
• Rove beetles• Soldier beetles
adultadult
larva
adult
larva
adult
Predatory True Bugs
• Stink bugs–Spined soldier bug– Twospotted stink bug
• Flower bugs–Minute pirate bug– Insideous flower bug
• Damsel bugs• Assassin bugs
adult
nymph
Predatory Flies
• Hover flies (flower flies)
• Aphid midges
• Robber flies
larvaadult
larva
adult
Lacewings
• Green lacewings
• Brown lacewings
Other Predators
• Wasps:–Yellowjackets
• Thrips:–Black hunter thrips
• Mites:–Phytoseiid mites
Biological Control: Parasitoids
• Develop at expense of a single host• Lay egg in or on host insect • Host is usually killed slowly• Enemy usually smaller than host
Parasitoids: typical life cycle
Categories of parasitoids• Endoparasites–Develop inside body of host
• Ectoparasites–Feed externally, attach to outside of host
Life Cycle of Parasitoid
Hyposoterwasp attacking caterpillar
Life Stages of Parasitoid
Trichogrammawasp attacking caterpillar egg
Parasitoids• Some wasps–Braconid wasps•On hornworm: Cotesia congregata•On imported cabbageworm: Cotesiaglomeratus
•On aphids: Diaeretiella rapae– Ichneumonid wasps•On diamondback: Diadegma insulare
Parasitoids• Some wasps–Braconid wasps•On hornworm: Cotesia congregata
•On imported cabbageworm: Cotesia glomeratus
•On aphids: Diaeretiella rapae
– Ichneumonid wasps•On diamondback: Diadegma insulare
–Other wasps•On whiteflies: Encarsia
•On caterpillar eggs: Trichogramma
Parasitoids• Tachinid flies–On squash bug:
Trichopoda pennipes–On striped cucumber
beetle: Celatoria setosa
adulteggs
pupaadult
Parasitoids
• Some species attack eggs **• Some species attack larvae• Some species attack pupa• Some species attack adults
** prevent the most damage
Our smartphone app!
• Name: Good Bugs +• Platforms:
–For iPhone & Android• Now free (was $2.99)• Topics:
–Natural enemies: i.d., biology, mgmt–Pollinators–Native plants that support them
& Vertebrate predators eat insects!• Bats• Toads• Birds• Geese• Hogs
Biological control by conservation of local
natural enemies: tactics
• Avoid broad-spectrum insecticides• Provide resources:–Pollen & nectar (refuge)–Spray sugar/protein mix–Winter shelter–Alternate prey (banker plants)
• Attract with lures
Insectary planting as refuge for natural enemies
• Adult parasitoids need nectar• Adult predators need pollen• Plant flowering border to
enhance biocontrol
cilantrosweet alyssum
dill
Phacelia
nasturtium
Conservation of local species• Commercial lures–Spined soldier bug–Ladybug–General
Conservation of local species
• Spray sugar/protein food source:– ‘Pred Feed’• 2.5 kg/hectare in cotton
– ‘Insect Food’ from Rincon-Vitova• 0.5 – 1 lb per gallon water
Conservation of local species• Provide diversity of habitats–Hedgerows–Windbreaks
Biological control by augmentation of local
natural enemies
• Tactics:–Buy from insectary–Collect and transfer generalists
Augmentation: Collect & transfer• What to do?–Hunt for generalist predators–Collect them–Transfer them to crop
• Who, where, when?–Ladybugs on Spirea in May–Lacewings & aphid midges on
apple leaves in early June–Damsel bugs on alfalfa, April-June
Spirea : bridal wreath
• Often infested by spirea aphid in May• Good source of ladybugs & lacewings
Banker plants for biocontrol by conservation
& augmentation
• Banker plant = a plant infested by a pest• Provide a ‘nursery’ of alternate food for
the natural enemy• Must be a very host-specific pest!• Example: hanging baskets of wheat
infested with grain aphids in greenhouse tomatoes
Guardian plantsfor augmentation bicontrol
• Used in greenhouse• Dual-purpose:–Pull pests: like an indicator plant or trap crop–Support natural enemies: like banker plants
• Benefits–Saves scouting time–Need fewer shipments from insectary
• Example: marigolds in pepper; beans in tomato; lantana in herbs
Starting augmentation biocontrol• Focus on one crop• Select natural enemy–Do before season starts–Learn biology & ecology
• Decide on protocol–Monitor pest–Use threshold to plan releases–Place orders early
• Release–Observe quality control
• Evaluation
Ratio of enemy to pest??
• 1:10 a general rule• ‘Safe balance ratio’:• 1-7 pests/enemy
• ‘Unsafe balance ratio’• 10-20 pests/enemy
Trichogramma(say: TRICK – o – gram – ma)
• Tiny wasps• Lay their eggs in pest eggs• The most widely augmented
enemy in the world
Biocontrol of European corn borer
• Egg parasitoid• Trichogramma ostriniae–New species, 1980s
• Research trials–Sweet corn: since 1991•MA, NY
–Peppers: 2002 – 2012 • VA, NY, PA, ME, MA, MD, DE
healthy
parasitized
Trichogramma ostriniaeon sweet corn
• 1st: inundative, every 2-3 days• Later: inoculative, early–Eggs glued on cards– Inoculative: One release of 30,000
wasps per acre when crop is knee-high–Place on plants or on wood stakes–Place at 1 or more sites per acre–Parasitism up to 52 days after release
• Does not overwinter in NY
Trichogramma ostriniaeon peppers
• 4 releases –1 week apart –mid July - mid August
• Number released–1st: 90,000/A –then 120,000/A
Cultural controls• Crop location• Crop rotation• Variety selection• Tillage• Mulching• Delayed planting• Trap cropping• Maintenance• Fertilizer• Irrigation
Cultural Controls
• Under-utilized tactics:–Delayed planting–Trap cropping–Combined delayed planting + trap
cropping
• Best as part of multi-tactic plan
Delayed planting
• Cucumber beetle–Problem if plant in late May–Less problem if plant in mid-June
• Squash vine borer–Same
• Bean leaf beetle–Peak populations in May, July–Fewer in June
Adjust planting date for Cabbage Maggot• Crop most susceptible if in
seedling stage when new adults are laying eggs
• Emergence of the adults: – on different calendar dates each year– but always at the same time that certain
well known plants are floweringGEN. PLANT AVG. BLOOM (Ohio)
1 yellow rocket early May2 day lilies late June3 Canada thistle early August4 New England aster early Sept.
Trap cropping• Lure pest away from main crop
to a more attractive crop• Once the pest infests trap crop:–Leave it (sacrifice)or
–Hand-pick pests from trap crop or
–Spray trap crop with insecticide
Trap cropping
• Planting time options–Same time–2 weeks early for trap crop
cash crop
perimeter trap crop
Perimeter trap crop
• Collards around cabbage• Diamondback moth
Cantaloupes surrounded by perimeter trap crop of buttercup squash
Trap cropping examples
Main crop Trap crop Target pest
cabbage collards diamondback mothcabbage kale harlequin bugcucumber hubbard squash cucumber beetlespeppers sweet corn (late) Europ. corn borerpotato eggplant Colo. potato beetle
To weed or not to weed?• Some weeds act as trap crop
–Smartweed in sweet corn for Japanese beetle
• Weeds are alternate hosts of some pests
–Remove horsenettle to control pepper maggot
–Remove curly dock to control rhubarb curculio
Tillage• Deep thorough plowing affects:
–Cutworms–Wireworms–Stalk borer (pupae)–Corn earworm (pupae)–Squash vine borer (pupae)
• Reduced tillage becoming more common (for soil conservation)
Irrigation• Affects diamondback moth– Sprinkler irrigation– 5 minutes at dusk– Daily– Disrupts flight and mating
Fertilizer
• Some pests like plants with excess nitrogen (e.g. some aphids) • Others opposite
Reflective Mulch
• repels immigrating winged aphids
Cultural control: trade-offsE.g. Straw Mulch• Benefits–Moisture retention–Weed suppression–Reduces soil splash–Reduces fungal spore dispersal
• Makes some pest problems worse–E.g. cucumber beetles, slugs
Mechanical Controls• Exclusion• Removal
Row covers
• 1o for temperature control• Also block pests
Row covers to exclude pests
• Key pests–Worms on cole crops–Beetles on beans–Leafhoppers on beans
• Disease vectors–Beetles on cucumbers
(before flowering)
Row covers to exclude pests• Install on day of planting• Remove–When first flowers appear
(cucurbits)–At final harvest (broccoli,
beans)
Row covers to exclude pests
• Lightweight– ‘Agri-bon 15’, ‘Insect Barrier’–90% light transmission
(vs 70-85% for heavier covers for frost protection)
–Sources:• Johnny’s Selected Seed: $122. (10’ x 500’)• Gardens Alive: $40. (8’ x 96’)
Row covers to exclude pests• Use with or w/o hoops
• Must be anchored tightly
Exclusion by netting
• Periodical cicada
• Birds
blueberry
grapes
Mechanical Control by Removal
• Shelter traps• Attraction traps• By beating/shaking *
• Removal by vacuum• By aspirator• Removal by hand
Removal by shelter traps
• Board trap for squash bug
• Tree bands for caterpillars
Codling moth
Gypsy mothSquash bug
Removal by shelter trapsFor squash bug:• Board or shingle • Place on ground near plant• Bugs leave plant at night,
shelter under trap• Check daily, early morning• Destroy bugs squash bug
Removal by attraction traps• Slugs• Dish of beer• Catches many slugs• Often not significant
decrease in population • Apple maggot: –One red sticky ball trap
per 100 real fruit• Japanese beetle–Place AWAY from crop
to be protected
Removal by tapping or shaking
• Into bucket or tray• By broom or snow shovel• Daily• Example: Colorado potato
beetle (adults, larvae)
Sanitation or ‘clean culture’
• Collect & destroy: –crop residue after harvest
–culled fruit
–alternate hosts
–storage & processing waste
• Plant clean nursery stock
Removal by roguing
– Pull out infested plant
– For isolated infestations only
– Example: cyclamen mite on peppers
Vacuum removal
• ‘BugVac’• Colorado potato beetle in potato• Lygus bugs in strawberries• High cost machinery• Soil compaction
Removal by aspirator• Aspirator = Mouth-operated
suction device• $8 – 14 from:–BioQuip–Forestry Suppliers–Gempler’s
• Good for flea beetles, bean leaf beetle, cucumber beetle
Flaming/burning
• Early-season control of Colorado potato beetle
• Post-harvest control of squash bug
Behavioral control• by pheromones
• By kairomones
Phot
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Com
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Behavioral control
• by pheromone mating disruption
• pheromone = chemicals emitted for communication within a species
Phot
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Com
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Mating disruption by pheromones
• Goal: control the pest population by preventing mating, thus no fertile eggs to start the next generation• In orchards 5+ acres• Two techniques: –Male confusion technique–Attract-and-kill technique
Tomato Pinworm: Mating Disruption
• Key pest in FL, CA, TX
• Best where fields are isolated or whole areas are treated
• Widely adopted since 1980’s, due to insecticide resistance
Kairomonesexample: cucurbitacin
• CideTrak D–Gustatory stimulant–Mix with insecticide
(such as Entrust)• Bait traps–Trap-out tactic
Poison bait: cucurbitacin + carbaryl (inside trap)Volatile lure: mimic squash flowers
Microbial Control
Control by micro-organisms that cause disease in insect• Bacteria• Viruses• Fungi• Protozoans• Nematodes
Micro-organisms for Insect Control
• Bacteria–B.T. = Bacillus thuringiensis•B.t. kurstaki (caterpillars) *•B.t. aizawai (caterpillars) *•B.t. tenebrionis (certain beetle larvae)•B.t. israelensis (mosquito larvae)
–Bacillus popillae (Milky Spore)
* OMRI
Micro-organisms for Insect Control
• Viruses–Cyd-X, Spod-X, Gemstar *
• Fungi–Beauveria bassiana (Mycotrol, Naturalis) *
• Protozoans–Nosema (Hopper Stopper; Nolo Bait) *
• Nematodes–Steinernema carpocapsae (Millenium)–Heterorhabditis bacteriophora (Symbion)
* OMRI
What is B.t.?• A natural soil-borne bacterium• Species: Bacillus thur in gi en sis• produces crystal-like proteins that
kill certain insects• Produced by fermentation methods• Discovered 1915; used since 1957
B.t. products• Sprayable–For caterpillars:•DiPel, XenTari, Biobit (Valent)•Javelin, Agree, CryMax, Deliver
(Certis)–For Colorado potato beetle:•Trident (Certis)
• Transgenic crops– ‘Attribute’ & ‘Performance’ sweet corn
How does B.t. work?
• B.t. must be eaten by target insect• B.t. contains toxins that are
activated by insect’s gut enzymes• toxins paralyze insect’s digestive
tract • feeding stops within 2 hours• death takes 1 - 5 days
Sprayable B.t.: performance• Sometimes erratic due to:–Breakdown in U.V. light–Reduced toxicity against older larvae– Incomplete spray coverage–Too long a spray interval
• Best if:–Target young larvae–Apply at 3-4 day intervals–Get thorough coverage •Lot of water (>35 gal/A)•Good pressure (60 psi)
Chemical control
Chemical control
• Insecticides
• Repellents
• Attractants
Do any pesticides have valid place in organic agriculture?
• Strict organic practitioners: no• Many organic practitioners:
yes, if natural origin
OMRI: The Organic Materials Review Institute
• Certified organic growers• List of products
–Fertilizers–Pesticides
• Crops & processing
Example of label with OMRI logo
Insecticide Classification
• By origin
• By mode of action
Insecticides, by Origin• Natural
– Minerals & elementals– Oils & soaps– Abrasion agents: diatomaceous earth– Botanicals (plants)– Microbials– Compounds derived from microbes
• Synthetic– Mimics of natural insect pheromones– Mimics of natural insect hormones– Petroleum-based synthetic chemicals
ok
not ok
Note on natural insecticides
• Can be toxic to natural enemies• “Natural” is not always good!
Insect control products on OMRI ListCategory Action Item
Narrow spectrum
Mating disruption (behavioral control)
pheromones
Cause illness (microbial control)
virusesbacteria
Broad spectrum
Cause illness(microbial control)
fungi
Smothering soaps, oils
Abrasion diatomaceous earth
Nerve poisons spinosad (Entrust)pyrethrins (PyGanic)
Repellency kaolin, garlic,neem / azadirachtin
Minerals & elementals
• kaolin• iron phosphate• sulfur
‘Surround’
• A.I. = kaolin (clay)• ‘Particle film technology’• Broad spectrum crop protectant• Photosynthesis not affected• Acceptable for organic production
Repellent:‘Surround’ on pumpkin
‘Surround’ on apple
Smothering or suffocation agents
• oils: – from petroleum– from plants
• insecticidal soaps:– potassium salts of fatty acids
Abrasion agent:Diatomaceous earth• Silicon dioxide = fossilized remains of algae• Disrupts water balance• For indoor pests: sold alone• For food crops: sold in mix with pyrethrins• Not rainfast
Insecticides from plants (botanicals)
• pyrethrum (chrysanthemum)• azadirachtin (neem tree)• garlic extract• [ sabadilla ]Not on OMRI list:• capsaicin (hot pepper)• nicotine (tobacco)
From the neem tree
azadirachtin(extract)
neem seed oil
pyrethrum(from chrysanthemum)
& pyrethrins(components of pyrethrum)
• Allowed for organic:• alone• + oil• + soap
pyrethrum (from chrysanthemum)
& pyrethrins(components of pyrethrum)
• Allowed for organic:• alone• + oil• + soap
• Not allowed:• + PBO= piperonyl butoxide
What’s PBO?• PBO = piperonyl butoxide• synthetic sassafras oil• A synergist• When mixed with some insecticides,
makes them more active–Most common with pyrethrins–Also used with pyrethroids, rotenone, &
carbamates• Prevents enzymes from detoxifying
the a.i. before it acts on target site
Efficacy of Pyrethrins
• Pyrethrins + PBO
–Very effective in field & lab tests
• Pyrethrins + oil
–Not effective in lab tests
• Pyrethrins + soap
–Not effective in lab tests
Microbial insecticides:cause disease in insects
• Bacteria• Viruses• Fungi• Protozoans• Nematodes
Insecticides derived from
microorganisms
• spinosad–from a soil actinomycete–discovered behind rum
factory in Carribbean
Insecticides derived from microorganisms:spinosad in ‘Entrust’
• Excellent for caterpillar control• Use 3 - 6 fl oz/acre• $403 - 489/quart!
Mimics of natural insect hormones
• Types– juvenile hormone–molting hormone–chitin biosynthesis
• Biorational• Not on OMRI list
Insect Growth Regulators (IGRs)
• Normal hormones:–Control duration of immature stages–Control when immature becomes adult
• IGRs control insects by modifying normal insect development–Block ability to change immature to adult– Force change to adult before physically
able to reproduce
Insect Growth Regulators
• Class: hormone receptor agonists– interfere with molting hormone• tebufenozide (Confirm)•methoxyfenozide (Intrepid)
– interfere with juvenile hormone• pyriproxyfen (Esteem)• neem (Azatin, Neemix)
Insect Growth Regulators
• Class: chitin biosynthesis inhibitors– Interfere with formation of exoskeleton–3 types:•Caterpillars: diflubenzuron (Dimilin)•Maggots: cyromazine (Trigard)• Leafhoppers: buprofezin (Courier)
Bioassays to test efficacy of insecticides on pests
• Basic set-up– 8 oz deli dish– Leaf sprayed both sides
• Residual tests–Pests added after residue
dry• Direct tests–Pests added before spray
Bioassay Results
• % Mortality, for all pests• Damage, for chewing pests• Importance: –#1: Prevention of damage–#2: Death of pest
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Bean leaf beetle
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Bean leaf beetle
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Potato Aphidtested on tomato leaves, 10/3/2006
3 replicates/treatment, 10 aphids/replicate
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A natural enemy: ladybug
oo
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Field trial on snap bean• Late planting (seed late August)• Heavy beetle pressure• Start sprays as soon as seedlings
emerge• Spray 10 times on 1- to 5-day schedule
– Azadirachtin– Capsaicin– Garlic– Neem seed oil– Pyrethrins– Rotenone
• Spray 5 times on 5- to 8-day schedule– Spinosad
• Spray 4 times on 7- to 10-day schedule– Carbaryl– Permethrin– Endosulfan
Field trial on snap beans(bean leaf beetle + spotted cucumber beetle)
Trends in insecticide efficacyspectrum Exc./Good Good/Fair Fair/Poor
broad pyrethrins + PBOcarbarylesfenvaleratelambda-cyhalothrincyfluthrinbifenthrin
acetamipridpermethrinmalathionpyrethrins + oilpyrethrins + soapazadirachtin
neem seed oilcapsaicingarlic
narrow spinosadsoaprotenonedicofol
B.T.oilendosulfan
in red if on OMRI list
How to use insecticides in presence of beneficial insects?
Choose product:• Selective (by mode of action)–Kills pest but not the natural enemies–Allows natural enemies to help kill pest–Example: B.t. (‘Dipel’)
or• Very short residual activity–Most botanicals
How to use insecticides in presence of beneficial insects?
• Choose placement:–Selective placement• In space• In time
–Provide refuge
‘Spot treatment’ allows refuge
• Spray border rows only, for pests that invade from one edge–Colorado potato beetle–Strawberry clipper weevil–Brown marmorated stink bug
Biobest:Webpage & mobile app on ‘side effects’for 21 natural enemies & 263 chemicals
Biobest: 4 predators & 5 OMRI products
similar trends on chart by Koppert
Trends?• Not harsh:–azadirachtin–B.T.
• Harsh:–soap (potassium salts of fatty acids)
• Mixed results:–spinosad–pyrethrins–mineral oil
Hierarchy of harshness to natural enemies
Spray conventional (non-OMRI) >>
Spray OMRI broad spectrum (soaps, oils, botanicals, fungi) >>
Spray OMRI narrow spectrum (viruses, pheromones, bacteria) >>
No spray
Costs of using chemicals for pest management?• Input $ costs–Materials–Labor
• Environmental costs
EIQ=Environmental Impact Quotient
• Developed at Cornell:–Joe Kovach et al. 1992–Website remains active
• www.nysipm.cornell.edu/publications/eiq/
EIQ: Allows comparisons• Basic EIQ value per chemical–Based on 14 effects: toxicity, leaching, etc.
• ‘Field use EIQ calculator’– Input name & % of active ingredient– Input application rate–Output: 1 number
• Small number = low impact (good)• Large number = high impact (bad)
EIQ examplesEntrust SC, 3 fl oz/A
Wettablesulfur, 12 lb/A
Javelin (B.t.), 1 lb/A
Field use EIQ
0.6 361 11.3
Consumer 0.1 92 2.1Worker 0.3 241 5.9Ecological 1.5 749 26.0
EIQ example: apples
Product Rate Field use EIQ
Imidan 70W 3 lb/A 69Pyganic 5EC 12 fl oz/A 1.4Entrust SC 7 fl oz/A 1.4Aza-Direct 24 fl oz/A 0.2Surround WP 25 lbs/A 190Wettable sulfur 12 lbs/A 361
EIQ example: sweet cornProduct Application
RateField use EIQ
Lannate LV 1.5 pt/A 9.6Warrior II 1.92 fl oz/A 1.2Coragen 3.5 fl oz/A 0.7Entrust SC 3 fl oz/A 0.6
Examples of organic tactics
• Cole crops• Cantaloupes & squash• Sweet corn
3 cabbage caterpillars & their parasitoids
Imported cabbageworm
Cabbage looper
Diamondback moth
Diadegma insulareoviposits on larvae
Cotesia larvae spinning cocoons
Cotesiaadult wasp
Copidosoma floridanum wasps emerging from one cocoon
Parasitoids of Diamondback:Ohio surveys 2011-2012
from Emily Linkous
Diadegma insulare, Parasitoidof Diamondback Moth Larvae
Adult wasp
Photo by Andrei Sourakov
Diamond-back
larvae
Diadegma insulare, Parasitoidof Diamondback Moth Larvae
• small wasp, 1/4” long• black body, red/brown marks• adult wasp lays egg in older caterpillar• new adult wasp emerges from pupa
Diamondback pupae
Healthypupa
Parasitizedpupae
Photo by J. Ogrodnick
Biocontrol of diamondback moth by Diadegma insulare in Ohio
• % of diamondback larvae attacked (Ohio 2011-2012):– 48% in plots without insecticide– 33% in plots with insecticide– 28% in commercial fields
Insecticide Imported cabbage-worm
Diamond-back moth
Cabbage looper
Natural enemies
Conventional Excellent control
Fair control
Good control
Poor survival
B.t. Good control
Good control
Fair control
Excellent survival
Caterpillar management on cole crops
Thus B.t. works best when diamondback moth or imported cabbageworm is dominant pest
Integration of microbial control & biocontrol of caterpillars on cole crops
• Plant border of sweet alyssum to attract parasitoids• Use the microbial insecticide BT as a
selective insecticide– ‘DiPel’, ‘Xentari’, etc.–Kills caterpillars–Does not kill parasitoids–Allows natural enemies to help kill pests
• Spinosad also easy on parasitoids
Choose Cabbage Variety to Avoid ThripsLess damage More damageBravo AzanFresco AtriaCheers ColeguardTitanic90 MegatonKingCole UptonSuperkraut Hinova
KrautpackerRodolphoSuperdane
Data on >80 varietiesTrials 1987-1999C.Hoy, K.Scaife, M.Kleinhenz
Adjust Cover Crops for Thrips• Used to protect soil over winter• Affects onion thrips–Overwinters in small grains–Does best in wheat–Does poorly in rye
Adjust planting date for Cabbage Maggot• Crop most susceptible if in
seedling stage when new adults are laying eggs
• Emergence of the adults: – on different calendar dates each year– but always at the same time that certain
well known plants are floweringGEN. PLANT AVG. BLOOM (Ohio)
1 yellow rocket early May2 day lilies late June3 Canada thistle early August4 New England aster early Sept.
Adjust irrigation timing for
caterpillars
• Sprinkler irrigation affects diamondback moth (adult)
– 5 minutes at dusk– Daily– Disrupts flight and mating
Integrated Methods for Cole CropsCultural Biological Chemical
• Caterpillars
• Thrips
• Flea beetles
• Aphids
• Root maggots
Cucumber beetles
Damage:
• Chew seedlings
• Chew on fruit surface
• Transmit bacterial wilt
Row covers: from transplant until first female flowers
(removal, July 19th)
‘Surround’ (kaolin)applied to cantaloupe after
row covers removed
CideTrak D• Gustatory stimulant• Buffalo gourd root powder• Cucurbitacin• Not insecticide• Mix with insecticide• 3.1 oz/A• On OMRI list (as adjuvant)• Costs $92.50 for 4-lb bag
Cantaloupes surrounded by perimeter trap crop of buttercup squash
Summary:Cucumber beetle management
• Biological–Conserve parasitoid flies
• Cultural:–Plant late (mid-June)–Perimeter trap crop
• Mechanical:–Row covers–Mass trapping
• Chemical–Surround–CideTrak D + Entrust
Corn earworm in sweet corn
• Source: moths migrate from Southern USA• Egg laying site: on silks• Egg hatch time: 2-3 days
Organic Alternative for Worms in Sweet corn: B.t. + Oil
(Ruth Hazzard, Univ. Mass.)
• ‘Zea-later II’ applicator– Hand-held– $99 (Johnny’s Selected Seeds)
• Mix:– 900 ml food-grade corn oil– Lecithin 5% (emulsifier)– 28.6 grams DiPel DF (a B.t.)– 100 ml water
• Treat:– Once, 5 days after silking begins– Squirt 0.5 ml of oil mix into each ear tip
Organic management tactics
Summary:• Many tactics available• Non-chemical:–Must be emphasized–Knowledge & labor intensive
• Chemical:–Usually as last resort–Choose least disruptive product–Beware efficacy fair to poor
Info on vegetable & fruit insect pest management
u.osu.edu/pestmanagement/
Questions?e-mail: [email protected]
phone: 614-292-2803
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