High Tunnel Fruit and Vegetable Production

1. High TunnelFruit and Vegetable Production Lesson Nine: Integrated Pest Management

2. Objectives Identify the components of integrated pest management. Recall the importance of integrated pest management to growers and the environment. Discuss a variety of control tactics available to manage insects, diseases and other pests.

3. High Tunnel and Insects • High tunnels create a unique environment • May lead to different insect and disease pests than greenhouse or field production • Even with these differences, the generalities of Integrated Pest Management apply

4. Integrated Pest Management • Commonly known as IPM • Common-sense, holistic approach • Uses knowledge of plants, pests, and the environment sensibly to reduce number of pests. • Reducing pests before unacceptable damage is done • Uses a combination of control tactics • Prevention • Monitoring • Control Techniques

5. Prevention • Use knowledge of past and potential pests to avoid future problems • Prevention Activities: • Choose resistant and adapted species when available • Plant according to best management practices • Plant disease- and pest-free transplants and seeds • Use sanitation practices • Irrigate and use mulch to minimize plant stress • Fertilize according to need

6. Monitoring • Inspection, detection and scouting • Find pests and diseases early • Use of trapping devices and visual inspection • Provides information to aid in pest control decision-making process • Inspect plants in high tunnel at least twice a week • Count pests • Specific locations and specific plant parts • Take good notes and observations • Pest, crop, number found and stage of insect growth

7. Control Techniques • Four different types of control techniques • Cultural (Prevention Techniques) • Biological • Mechanical (or Physical) • Chemical • The four management tactics can be used alone or in combination • Ultimate goal is to reduce or prevent pest injury

8. Control Techniques: Cultural • Horticultural practices that limit pest populations or reduce the amount of damage that pests might cause • Essentially the same as prevention measures • Control techniques include: • Maintaining plant health • Making proper plant selections • Choosing resistant varieties • Using crop rotation • Other practices that maintain healthy, vigorous plants

9. Control Techniques: Biological • Also known as bio-control • Uses living organisms to suppress or limit pest populations • Keeps populations down, does not eliminate pests • Low level of injury expected • Acceptability depends on tolerance level • Use of “natural enemies” • Organisms that attack pests • Three categories: Predators, Parasitoids, Pathogens

10. Control Techniques: Biological • Two main ways to use biological controls • Augmentation • Release of specific beneficial organisms for control of existing pest population • Conservation • Conserves natural enemies that are already present • Reduce use of broad-spectrum pesticides • Pathogens • Microorganisms: Bacteria, Fungi, Viruses, Nematodes • Weaken and kill pests by creating disease or infection

11. Control Techniques: Mechanical/Physical • This control method separates the pest from the crop by means of a device or action • Actions: • Handpicking pests directly from plants • Forceful water sprays to dislodge aphids • Pruning to remove diseased or infested plant material • Install insect screening over vents and side walls • Excludes larger insects

12. Control Techniques: Mechanical/Physical • Screening reduces airflow, increases temperatures • Often overlooked when growers are unaware • May reduce airflow by 5-10% with active ventilation • May result in 45% ‘wind reduction’ in passively ventilated tunnels – raised air temperature of ~5°F • Increase in temperatures could be partially offset by using peak vents or exhaust fans

13. Control Techniques: Mechanical/Physical • Screening • Standard window screening is an economical choice • Must be cleaned occasionally • Does not completely restrict influx of pests, reduces • Needed pollinators must be introduced and maintained • Biological controls that are naturally occurring outside the tunnel will be restricted from entering • Not all mechanical controls are effective • Ultrasonic and electromagnetic devices • Bug zappers • Insect traps (yellow sticky cards)

14. Control Techniques: Chemical • Use of pesticides, naturally occurring or synthetic • Adversely affect unwanted insects, weeds or plant pathogens • Affect plant growth • Repel insects from an area • Judicious use in combination with other tactics • Or, if other tactics do not give desired level of control • Thoughtfully chosen and properly timed application • Least toxic alternatives • Consider use of “soft” or “reduced risk” compounds • Consider environmental consequences

15. Importance to Growers • IPM practices must be compatible with objectives • Practices must be: • Economically viable • Effective • Understandable • Practices can be implemented in stages

16. Importance to Growers • Approach should improve grower’s profitability and reduce risk of crop loss • Monitoring used to determine economical timing • Provides greater peace of mind • High tunnel production is large investment • Proper field scouting for informed decisions

17. Importance to Environment • All practices must be environmentally sound • Benefits received from control vs. risks of that control should be considered before practice is developed • Reduces unnecessary pesticide applications • Pesticides are generally largest environmental concern with pest management • Fewer unwarranted pesticide applications such as “calendar sprays”

18. High Tunnel Insect Control • Major insect and mite pests of high tunnel crops should be given consideration • Avoid having lights on in evening or night near or inside the high tunnel • Security lights or lights for convenience • Lights attract a range of insects, particularly moths • These insects may inadvertently cause crop damage

19. High Tunnel Insect Control • Hornworms/Other Caterpillars of Tomato & Peppers • Damage usually occurs from midsummer to fall • Eat irregular holes in leaves and may defoliate plants • Camouflaged – often difficult to see • Fruitworms • Feed on green fruit • Damage is deep watery cavities on stem end of fruit • Inspect tomato plants for larvae on fruit and leaves • Threshold in high tunnel is one caterpillar • Can be handpicked or use insecticide sprays

20. High Tunnel Insect Control • Whiteflies • Tiny, resemble tiny white moths • Disperse from plants when disturbed • Most common on tomatoes and melons in late season • Damage done when in immature (nymph) stage • Suck sap from plant leaves • Spread viral diseases • Inspect plants for off-color or stunted plants • Yellow sticky cards will monitor adults • Spray with insecticide/insecticidal soap

21. High Tunnel Insect Control • Aphids • Migrate into high tunnel from wild hosts • Establish colonies on plants • Soft-bodied, pear shaped small insects • Usually on underside of leaves, may be found on stems • Suck sap from plants • Leaves curl under, become deformed, weakens plants • Can be vectors of plant diseases • Scout plants closest to openings • Wide range of control options

22. High Tunnel Insect Control • Spider Mites • Tiny (~.5mm long), live on undersides of plant leaves • Puncture plant cells to feed on the sap • Speckled “bronzing” discoloration of leaves • Reduced plant growth • Possible early defoliation and death • Thrive in hot, dry weather and are more likely from mid season through fall

23. High Tunnel Insect Control • Spider Mites (Continued) • Inspect leaf undersides for egg webs, cast skins and all stages • Control weeds and practice clean mowing around tunnel to help prevent movement from outdoors • Begin treatment when symptoms appear • Insecticidal soap or other miticide • Miticides do not kill eggs so repeat application should be considered

24. High Tunnel Insect Control • Thrips • Small (1/16 inch long) and elongated • Found in flowers or on the undersides of leaves • Damage to plants is caused by adults and nymphs • Scrape the surface of leaves with mouthparts and feed on exuding sap • Leaves will have small, silver streaks • Plants look as though they havebeen sandblasted

25. High Tunnel Insect Control • Thrips (Continued) • Early detection is important • Frequently inspect blossoms and leaf undersides • Sticky traps can detect adult winged thrips • Apply systemic, targeted insecticides at transplanting • Effective in controlling for ~35 days on certain crops • For control, spray contact insecticides

26. High Tunnel Insect Control • Cucumber Beetles • Same beetles that that will attack field-grown cucurbits • Transmit bacterial wilt • Can damage high tunnel melons • Overwintered adults feeding on transplant leaves and stems can kill small plants • Surviving plants may be infected with bacterial wilt • Frequently feed on the fruit surface • Reduces aesthetic appeal • Creates openings for sap beetles and disease organisms

27. High Tunnel Insect Control • Cucumber Beetles (Continued) • Can be excluded from transplants by using row covers in the high tunnel • Systemic insecticides applied at transplanting will provide up to 35 days of control • Long enough to reduce bacterial wilt and infection • Foliar insecticides provide further control through growing season • Avoid insecticides that may be toxic to pollinating insects • No effective biological control techniques

28. High Tunnel Plant Disease Control • High tunnels can reduce disease impact by: • Elevating soil temperatures slightly • Enough to prevent common cool weather damping-off and root rots • Keeping foliage dry • Preventing establishment of most foliar diseases • Powdery Mildew can germinate • Absence of free water • Can be even more serious than in a field-grown crop

29. High Tunnel Plant Disease Control • Disease management should include the following considerations: • Use plastic mulch combined with trickle irrigation • Keeps foliage dry, reduce splash of soil-borne pathogens • Maintain humidity to remove excess moisture • Provides conditions conducive to certain diseases • Use ventilation and follow plant-spacing guidelines • Use disease-resistant varieties when possible • Always start with disease-free seed and transplants

30. High Tunnel Plant Disease Control • Disease management should include the following considerations: • Provide optimal growing conditions • Proper irrigation, fertilization, staking, pruning, etc. • Increase plant health and vigor • Practice sanitation to remove and destroy infected plants as they are found • Pick produce frequently, cleanly and completely • Remove all over-ripe and damaged produce • Remove all plant residues at the end of the season • Practice crop rotation

31. High Tunnel Plant Disease Control • Powdery Mildew • Major problem for all high tunnel crops • Environmental conditions in tunnel favor development • Produces white, powdery colonies • On leaves, petioles, and stems of infected plants • Usually appears on lower leaves • Gradually spreads through the canopy • Plants become weakened from leaf loss • Fruit size can be significantly reduced

32. High Tunnel Plant Disease Control • Powdery Mildew (Continued) • Choose resistant cultivars when possible • Inspect plants regularly, starting at fruit set • Many effective fungicides are labeled for control • Includes several synthetic fungicides and organic products, such as mineral oils & potassium bicarbonate • Alternate synthetic fungicides to prevent the development of resistance