michelangelo la spina - wordpress.com · 70 control ervi aphidoletes adults aphidoletes larvae...
TRANSCRIPT
Michelangelo La Spina, PhD
Integrated Control of Aphids
What is an aphid?
• Also named: plant lice; green flies
• Sap-sucking insects • Soft bodies • Small: 1.0-4 mm
• Feed on many hosts:
• Monocotyledons • Dicotyledons
Cauda
Cornicles
Life cycle: How do aphids reproduce?
Spring - Summer
Fall - Winter
Primary host Crop
Herbaceous plants
eggs
male
Females: oviparae
fundatrices
Apterous virginoparae
Aphid damage
Foliar and floral damage: • Chlorosis • Rolling • Deformation
Reduced photosynthesis: • Honeydew • Fungi
Virus transmission: • Cucumber mosaic
virus • Leaf mottling • Stunting
Why are aphids a problem?
0
100
200
300
400
500
600
700
800
900
1 3 6 8 10 13 15 17
• Aphids can DOUBLE their population in as little as 2-3 days!
• Clonal reproduction: no males
• Telescoping generations
• They spread really fast
Aphid identification
Hi! What’s your name?
Aphid identification
I’m an adult
Aphid identification
Look my head
Aphis gossypii: Melon aphid Myzus persicae: Green Peach aphid Aulacorthum solani: Foxglove aphid Macrosiphum euphorbiae: Potato aphid Macrosiphoniella sanborni: Chrysantemum aphid
Aphid identification
Look the length of my antennae
Bigger than body Shorter than body
Myzus persicae: Melon aphid Aphis gossypii: Melon aphid
Aulacorthum solani: Foxglove aphid Macrosiphum euphorbiae: Potato aphid Macrosiphoniella sanborni: Chrysantemum aphid
Aphid identification
Look my head again
Aphis gossypii: Melon aphid Myzus persicae: Green Peach aphid
Green Peach Aphid, Myzus persicae
Green Peach Aphid, Myzus persicae
Melon Aphid, Aphis gossypii
Foxglove Aphid, Aulacorthum solani
Dark green spot above each cornicle
Potato Aphid, Macrosiphum euphorbiae
Chrysanthemum Aphid, Macrosiphoniella sanborni
Monitoring
Early detection - scouting
What and where to scout?
Sticky cards
Honeydew and/or white cast skins
Leaves and flowers
Place in the plant
• Only winged aphids
• Not for mass trapping
• Don’t wait to see an aphid
• Early detection?
Monitoring
Sticky cards
• Depends on the aphid and the crop
• Some aphids prefer substrate level, others flowers – Bottom leaves deformation – Yellow spot – Aggregation on flowers
Monitoring
Where to scout? Place in the plant
• Most of aphids prefer underside of leaf: to detect them -> turn leaves over
• Use an hand lens to identify them
• Check if they are alone: probably there are bios!!!!
Monitoring
Check underside of leaves
• Honeydew: small droplets – Shiny – Black fungi
• White cast skins:
– Aphids are around – Aphids are on the leaf
• If you see these signs,
aphid colony is quite big
Monitoring
Honeydew and/or white cast skins
• Specialists on aphids – Aphidius – Aphelinus
• Lay egg(s) inside the aphid
• Larvae eat the aphid from
inside
• Hyperparasitoids: inconvenient
Biological control
Parasitoids
Biological control
Parasitoids
5-7 days and
Surprise!!!!
• Generalists – Disruptive searching behaviour
• Kill and eat – Stealthy searching behaviour
• Anesthetize and eat
• Larvae and adults: eat aphids
• Adults eat pollen, larvae eat
aphids
Biological control
Predators
Biological control
Ladybirds
Biological control
Lacewings
Biological control
Gall midge
Biological control
Hoverfly
Biological control
Matching Natural Enemy
Natural Enemy Green Peach Aphid Melon Aphid Potato aphid Foxglove aphid
A. colemani
A. matricariae
A. ervi
Aphelinus
Aphidoletes
0
10
20
30
40
50
60
70
Control Ervi AphidoletesAdults
Aphidoleteslarvae
Distribution of aphids after an attack
Aphids on the leaf Aphids on the fluon cup Aphids Elsewhere
Aphids and biocontrol agents
Disruptive vs Stealthy bios
• Aphidius ervi causes aphid dropping behaviour
• Aphidoletes aphidimyza adults and larvae do not cause dropping behaviour
• Read the label release recommendations
• Check quality: – Wasps alive – Wasp walking
• Use bio-boxes
• Store products in the correct
place (label)
• Aphidoletes is delicate: – Release at dusk – Don’t remove from original
container
Biological control
Release Recommendations
Photo: Betsy Lamb, Cornell
• Botanigard: Beauveria bassiana containing insecticide
• Met52EC : insect pathogenic fungus Metarhizium anisopliae strain
Biological control
Biopesticides
• Met52 EC and Pea protein have a good control of aphid population, especially at week 1.
• There are no differences between Met 52 EC and Pea protein.
• Use Met52 EC or Pea protein as an alternative to chemicals.
Biopesticides in greenhouse
0
100
200
300
400
500
600
week 0 week 1 week 2
Nu
mb
er o
f ap
hid
s
Control
BeLeaf
Met52 EC
Pea Protein
• Systemic Pesticides – Beleaf (flonicamid) – Endevor (pymetrozine) – Affects the aphid’s feeding mechanism; starves to death in 3-4 days. – Compatible with biocontrols
• Insect Growth Regulators – Enstar II – Prevents aphids from turning into adults – slow population reduction – Compatible with biological control
Chemical control
IPM strategy
Crop
Bio Bio Bio
Ap
hid
nu
mb
ers
Chemical
Temperatures and Bios
Development time in days
Pests 59°F
(15°C) 62.6°F (17°C)
68°F (20°C)
71.6°F (22°C)
77°F (25°C)
82.4°F (28°C)
86°F (30°C)
91.4°F (33°C)
95°F (35°C)
Green peach aphid — 9.6 7.0 6.0 5.5 5.4 5.4 6.2 —
Melon aphid 13.5 — 6.9 — 5.3 — 4.4 — 4.5
Foxglove aphid 11.4 8.4 6.9 9.5
Development time in days
Beneficials 59°F
(15°C) 62.6°F (17°C)
68°F (20°C)
69.8°F (21°C)
77°F (25°C)
86°F (30°C)
Ervi 27.3 — — 19.9 — —
Colemani 23.6 — 13.5 — 9.8 12.0
Matricariae 27.7 — 14.8 — 11.6 12.3
Aphidoletes — 45.0 21.0 — 16.5 —
Preventative vs Curative
0
10
20
30
40
1 3 6 8 10 13 15 17
Nu
mb
er A
phi
ds
per
blo
ck
Preventative vs Curative
Curative Preventative
0
0.5
1
1.5
1 3 6 8 10 13 15 17
Nu
mb
er o
f A
. erv
i per
b
lock
Preventative vs Curative: Ervi
Curative Preventative
• In the curative treatment A. ervi was able to reproduce in the greenhouse.
• In the preventative treatment A. ervi leave the greenhouse.
• Aphids numbers do not increase in the preventative treatment, however they increase in the curative treatment
Acknowledgements
• Sarah Jandricic • Rose Buitenhuis • Rebecca Eerkes • Ashley Summerfield • Taro Saito • Michael Brownbridge
