This presentation was given on October 10, 2013, in Hartselle, AL. Has some news slides about factors that influence insect pests in high tunnels and some slides on how to improve quality of organic produce with correct use of organic insecticides. Refer to the other long version of the high tunnel IPM presentation I have for details about the three-tiered IPM recommendations for Alabama producers.

1. Integrated Pest Management in
High Tunnel Crops
Dr. Ayanava Majumdar (Dr. A)
Ext. Entomologist &
State SARE Coordinator
Auburn, AL 36849
Tel: (251) 331-8416
bugdoctor@auburn.edu
HT Training Workshops, AL, 2013

2. Why are INSECTS so successful?
• Small size
• Small food requirement
• Rapid and prolific reproduction
– Parthenogenesis
• Grow by molting (control over
growth rate)
• Life stages feed on different
substrate

3. Why are INSECTS so successful?

4. High Tunnel Environment
•
•
•
•
•
Season extension = Early onset of insects!!
It gets hot & humid (PASSIVE VENTILATION)
Heat shortens insect lifecycles.
It is very dry on leaf surface (NO RAINFALL)
High planting density & diversity (HOST PLANTS)

5. High Tunnel Basics
• Bottom line 1: Prevention is better than cure!
• Bottom line 2: Manage insects when they are
small/low numbers!
• Bottom line 3: ANY INTERVENTION IN INSECT
ACTIVITY IS BETTER THAN DOING NOTHING!!

6. What is it?
Greenhouse whitefly, Trialeurodes
vaporariorum (flatenned wings)
Silverleaf whitefly, Bemisia tabaci
(tented wings)
• First reported from USA in 1870
• Adults are 1.5 mm long, covered
with white waxy material
• Piercing and sucking mouthparts
• Eggs laid on plants
• Crawlers or nymphs feed on one
location
• 30 days for one generation
• Higher temps may inhibit the
whiteflies
• Biological control: Encarsia formosa

7. What is it?
Potato aphid, Macrosiphum
euphorbiae
Green peach aphid, Myzus
persicae
Monitoring/scouting techniques:
Sample ten plants in several locations
Yellow sticky traps at edge of field
Like cool, dry weather
Watch for ants and lady beetles
ET = 50% leaves with aphids
Host range: 40 host plants

8. What is it?
Onion thrips, Thrips tabaci
Tobacco thrips, Frankliniella fusca
Host plants:
tomato, peanuts, cotto
n, beans
Monitoring/scouting techniques:
Use sticky cards (yellow, blue)
Bag and shake technique
No action threshold
Use resistant varieties (BHN
444, 589, 640, Bella Rosa)
Tomato spotted wilt destroys plants

9. What is it?
Monitoring/scouting techniques:
Flea beetles (many
species)
Monitor level of defoliation
Sample small plants with sweep net
during morning hours
Observe activity of parasitoids, predators
(sweep net)
ET = 5-10% defoliation early season, 2530% defoliation mid-season
Host plants:
potato, tomato, peppers, br
occoli, cabbage, okra, etc.

10. Spider mites
•
•
•
•
Major pest of open field & high tunnel crops
Extensive webbing on leaves/stems
Rapid buildup in hot dry weather
Difficult to control with approved pesticides

11. Identification & Scouting
Twospotted spider mite (TSM):
• Carry a 10X hand lens
• Females are larger than males
• Oval adults, eggs glued to webbing
• Underside of leaves & leaf tips
• Wide host range
Twospotted spider mite
Tetranychus urticae
Tomato russet mite (TRM):
• Smaller than TSM
• Carry a 14X hand lens
• Adults are elongate
• Infestation starts from lower leaves
• Leave edges, stems, fruits (small)
Tomato russet mite
• Solanaceous host plants
Acilops lycopersici

12. Crop damage
TSM:
– Leaf drying
– Extensive webbing
– Slight bronzing
TRM:
– Greasy bronzing
(russet color)
– Sudden dry out
(lower leaves)

13. What is it?
• Polyphagous insect
(tomato, pepper, cotton, soybe
an, alfalfa)
• Have many wild hosts –
lambsquarter & pigweed
Beet
armyworm, Spodoptera
exigua
• Creamish or light-green
caterpillar, 4 pairs of prolegs
• Black spot on thorax just above
the leg
• Early instars feed voraciously
• Moths are attracted to weak
plants
Damage to pepper plant

14. Starting Point for IPM…
• Emphasis on Pest Detection & Correct Identification:
– INSECT PHEROMONE TRAPS for improved scouting
– Trap Catch = Pest Density X Pest Activity (Taylor, 1963)
– Insect Monitoring Project in Alabama, 2009-2010
Stink bug trap
Sticky wing trap
Corn rootworm trap

15. What is it?
Southern green stink
bug, Nezara viridula
Monitoring/scouting techniques:
Use a sweep net
Use pheromone trap (expensive?
cumbersome?)
Intensify scouting at fruit setting
Host: >52 plants
Brown stink
bug, Euschistus servus
ET = 0.25 bugs per 10 plants (green fruit stage)
Lygus bug, Lygus
lineolaris
Stink bug feeding injury

16. Integrated Pest Management
(IPM) Tactics

17. What is IPM?
• “Integrated pest management (IPM) is a threshold based
decision management system which leads to judicious use
of multiple pest control tactics.”
• IPM is currently insecticide-intensive…
• Major losses occur due to:
• Lack of early detection of insects
• Insecticide resistance by misuse
• Loss of natural control with insecticides

18. USDA National Organic Program Standards
(applicable in gardening situation also!)
• Level 1: Systems-based practices (variety
selection, sanitation, crop rotation, weed
control, trap crops*)
• Level 2: Mechanical and physical practices
(barriers, lures/traps, repellents, hand-picking, net
house*)
• Level 3: Biorational & other material (OMRI
*Discussed later in this presentation

19. Trap Crop Applications
Sorghum trap crop on two
sides of a high tunnel can act
as barrier to pest migration.
Sorghum &
sunflower trap
crops ahead of a
high tunnel.

20. Trap crop study for leaffooted bugs
(Clanton, AL, 2012)
Manual removal in organic situation
19
18
Insecticide treatment and/or
manual removal in organic situation
11
DKB5400 (sorghum trap crop)
NK300 (sorghum trap crop)
Sunflower (trap crop)
Tomato (main crop)
4
0
2
0
2
2
0
4
0
2
3
0
0
1
0
Obs. 1 Obs. 2 Obs. 3 Obs. 4 Obs. 5 Obs. 6 Obs. 7
(21 July)
(4 Aug.)
(13 Aug.)
(5 Sep.)
(7 Sep.)
(20 Sep.)
(4 Oct.)
Numbers indicate leaffooted bugs (LFBs) on 20 heads of trap crops and 20 tomato plants for comparison
purposes. Trap crops planted on May 16. Main crop planted on June 1. Trap crop treated with Mustang
Max (zeta-cyper. @ 4 oz/A) on Sept. 5, 2012. Result = 78% LFB control in 5DAT. Tomato main crop is
attacked by LFBs after the trap crop is ineffective (in October).

21. Damage
 Both adults and larvae feed on foliage by first
making small holes; later serious defoliation
Defoliation of larvae on turnip
Mass attack of adults on napa cabbage

22. Field Trials-Managing YMLB with Trap crop
Spring 2011
Napa cabbage
Main crop
35 ft
Trap crop
Turnip

23. First Net House in Alabama (2010)
Location: Baldwin County, AL
Dimensions: 150 ft X 48 ft X 17 ft
Entrance: Double door
Fabric mesh 30-50 as insect barrier
Mesh size depends on target insect & cost

24. Insect Netting Applications
Insect netting on the
sides and front
(improved air flow)
Use insect netting over the
entire high tunnel frame

25. Who kills Pests?
Natural Enemies
Predators: – Ladybugs, Spiders
• General feeders
• Eat several prey
• Larger and stronger than the prey
Flicker.com
Parasitoids (=parasites): – Wasps, Flies
• Specialist feeders
• Kill only one host (pest)
• Smaller than the host
http://www.harvesttotable.com/2012/06/parasitic-wasps-beneficial-insects/
Pathogens: – Bacteria, Fungus & Viruses
• Micro-organisms that cause diseases in
insects
extension.entm.purdue.edu
25

26. Insecticide Mode of Action (MoA)
Physical dessicant – kaolin clay, ash
Contact action – vegetable oils, horticultural
oils, neem, pyrethrin, insecticidal
soap, spinosyn, Beauveria, Metarhizium
Stomach action – Bt (Dipel)
Volatile action – Garlic Barrier, Cinnamite

27. Fruit quality with Xentari (Bt aizawai)
(Cullman, 2012)
Untreated crop with 90%
caterpillar damage &
irregular fruit size
Xentari foliar treatment with
<20% caterpillar damage &
uniform fruit size

28. Fruit quality with Pyganic (pyrethrum)
(Cullman, 2012)
Untreated check
Pyganic foliar
30% fruit
damage
90% fruit
damage

29. Fruit quality with Xentari (Bta) + Pyganic
(Late season treatment, Cullman, 2012)
Check plots
Xentari + Pyganic foliar

30. High Tunnel Pest Management Tips
•
•
•
•
•
Practice sanitation and strict weed control
Regular irrigation, reduce stress
Scout weekly to find insect hot spots, then treat.
Choices: Conventional (drip) or Organic (foliar)
Organic approved i-cides:
– Bt products (Xentari®, Thuricide®)
– Spinosad (Entrust®, Monterey Spinosad®)
– Pyrethrin (Pyganic®, Natural Pyrethrin®)
– Neem with azadirachtin (Molt-X®, Neemix®)
– New products: Azera
• Use insecticidal oils carefully (do not use >85F)
• Use a good quality backpack sprayer.

31. High Tunnel Pest Management Tips
• Use biological control when possible.
• Use biological control and organic insecticides at
the first detection, continue for 2-3 weeks.
• Reduce insecticide use when using nonselective
insecticides.
• Treat the bottom on leaves and soil below the
plants.
• Mix fresh spray solution and calibrate sprayer.
Change nozzles when needed.

32. EXTENSION RESOURCES

33. Know the IPM
Campaign!
Campaign items: Display
magnets, bookmarks (4 designs), IPM
exhibitions

34. Vegetable IPM Website
www.aces.edu/go/87

35. Alabama SARE Website

36. Join Vegetable IPM on Facebook!
Advantages: Live updates, interact with
researchers, videos and photos, IPM contest

37. Join Commercial Horticulture on Facebook!
Advantages: Live updates, interact with
researchers, videos and photos, IPM contest

38. The IPM Communicator
(A FREE electronic newsletter)
To signup: Email bugdoctor@auburn.edu
Or sign up today on the sheet provided!

40. Acknowledgements
Chris Becker, REA
Willie Datcher, REA
FUNDING SOURCES: USDA Organic Agriculture
Program, SARE initiative, Specialty Crops Grant, Wallace