Orius insidiousus- Minute Pirate Bug

Larva and adult feed on thrips, mites, and insect eggs. 

You can grow Orius on flowers like alyssum that can grow as an understory. 

Intro: Orius insidiosus, minute pirate bug, is a general predator that targets thrips, mites, aphids, small caterpillars & other soft-bodied insects.

Favorable conditions are moderate temperatures around 59º F (15º C), > 60% RH. Diapause occurs with short day lengths. Orius can't survive without prey, so it is best to release Orius after thrips populations have become established or when pollen is also available. If prey is abundant, Orius will kill more thrips than it needs to survive. If Cucumeris has been released prior to Orius, Orius will feed on Cucumeris to become established. Cucumeris populations will decline briefly and then recover as thrips populations decline.

Up to 5,000 per acre OR 1-2 per 10 sq ft OR 1-4 per plant

Release twice, two weeks apart, to overlap the adult and immature life stages

Care and Handling:

Receive

• Ready to use on arrival
• Shipped as combination of nymphs and adults in inert carrier

• Inspection should show some movement of predators

Hold

• Storage not recommended because of cannibalism
• Can be stored 1 –2 days at 47º - 50º F (8º - 10º C)

Release

•  elease when thrips populations or pollen sources are present
• Release by gently shaking onto plants or by opening containers in greenhouse and allowing to disperse

·       Release directly into hotspots and infested areas

·       Release in groups of 25 - 50 insects to encourage mating

·     Because eggs are deposited in new plant growth, avoid loss of eggs by introducing Orius after removing side shoots

• Avoid extreme heat, and low humidity

Biology:

Appearance

·     Egg: ~ 0.15 inch (4 mm) long, whitish egg found on main stems, leaf veins, flowers or petioles

o   Most often deposited on side shoots and tips and newly emerged plant growth

• Nymph: 0.02 – 0.07 inch (0.5 – 1.8 mm) long wingless nymph
  • Colorless when they hatch, darkening to yellow, then dark brown as they grow
• Adult: 0.078 - 0.1 inch (2 - 2.5 mm) long, slightly oval shaped body with slightly pointed head and tail, mostly black with lighter markings on the wings

Behavior

• Nymph and adult stages of Orius move very quickly
• Nymph crawls from plant to plant via leaves
• Adults are good flyers and move efficiently to locate prey
• Adults are attracted to, and often found in, flowers where they feed on thrips and pollen
• Orius pierces its prey with mouthparts that suck out body fluids
• Orius often kills more thrips than it needs to survive
• Orius nymphs may turn cannibal if no other food is available

Environment

• Tolerates 59º - 82º F (15º - 20º C)

·        Optimum conditions > 59º (15º), > 60% RH

·        Diapause occurs with day lengths < 11 or 14 hours

o   This can be avoided with supplemental lighting

• Adult females stop laying eggs at < 14 or 16 hours daylight
• Native to North and South America

Lifecycle

• Egg to adult: ~ 3 weeks at 70º F (21º C), faster at higher temperatures

• Egg: 4 - 5 days at 70º F (21º C)
• Nymph: ~ 3 weeks at 70º F (21º C)
  • 5 instar stages (5 molts)

• Adult: 3 - 4 weeks
  • Polyphagous predator (consumes multiple food sources)
  • Feeds on pollen and all mobile stages of thrips and to lesser extent aphids, mites, small caterpillars and other soft-bodied insects
  • Deposits ~ 30 eggs in lifetime at ~ 2 eggs per day
  • Enters diapause in fall

RELEASE RATES:

General

1 – 2 predators per 10 sq ft (1 sq m)

1 – 4 per infested plant until established

2,000 – 4,000 per acre (5,000 - 10,000 per ha)

Use higher numbers in hotspots

Release twice, 2 weeks apart to establish predator

Indoors

Cucumbers:

  1 per plant OR 1 per 10 sq ft (1 sq m)

  Weekly for 2 weeks

Sweet peppers:

  2 - 3 per 10 sq ft (1 sq m) in hot spots

Target Pests/Crops:

Preferred food

Western flower thrips (Frankliniella occidentalis)

• Onion thrips (Thrips tabaci)

Alternate food

• Aphids, mites, small caterpillars (ex. corn earworm) and other soft-bodied insects

Primary crops

• Used primarily in indoor greenhouses. May also be used in interior plantscapes, outdoor gardens and flowers.

Related Products:

• Cucumeris
• Hypoaspis
• D Vac
• RVI Insect Food
• (*add links)

PROGRAM SUCCESS:

Best Results

·       Orius may be used with Cucumeris or Hypoaspis

·       Until enough thrips are present to use Orius, use Cucumeris, on cucumber plants and Degenerans, Amblyseius degenerans, on pepper plants as soon as pollen is available on both[A1] 

·       Orius is not effective for thrips control on tomatoes

·       Orius has been shown to be an effective control for western flower thrips on greenhouse cucumbers and sweet peppers

·       Works best on flowering plants that produce pollen

·     Orius is most effective for pests with life stages that inhabit flowers (e.g., flower thrips)

·       Areas where plant foliage touch aid predator dispersal

·     Because eggs are deposited in new plant growth, avoid loss of eggs by introducing Orius after removing side shoots

·    To prevent Orius from diapausing, provide supplemental lighting to increase day length to 14 hours or longer

·    Blue sticky traps with thrips lures or vanilla extract on them will attract thrips away from crops

Pesticides

• Endosulfan will kill Orius
• If necessary, insecticidal soap or horticultural oil can be used to reduce thrips numbers before beneficials are released as they act on contact and do not leave toxic residues
• For specific effects of pesticides on Orius, see pesticide toxicity chart (*insert link to RVI approved toxicity chart)

Refuges

·       Plant sequentially flowering, pollen producing plants to attract and assist the survival of Orius and other beneficial insects

·       Plant chrysanthemum or fennel as a thrips trap crop

Monitoring

• 100% mortality of all pests is not required to prevent economic losses to market crops

• Monitor for thrip populations using blue sticky cards with thrips lures or vanilla on them

• • General sticky card monitoring for thrips requires 25 cards per acre
  • Place near possible entry points in greenhouses (vents, doors)
  • General sticky card monitoring for thrips requires 25 cards per acre
• Orius adults are attracted to yellow sticky traps
  • This should not be a problem if traps are placed at a rate of 1 trap per 100 plants or more
• Four or more Orius bugs found in traps per week indicates that enough Orius are present to bring thrips under control

·     Orius adults and older nymphs are easy to monitor in cucumber and pepper flowers, where they are found feeding on thrips and pollen

• It takes 4 to 6 weeks after the release of Orius before thrips populations markedly decline

Cultural Practices

·       Maintaining a 10 ft (3 m) weed free area around crops or greenhouses will help keep away pests (consider planting this area with beneficial insect refuge cover crops)

·       Remove infestations or destroy plants harboring heavy infestations

• Discard infested plant debris and prunings

• At the end of the season, completely remove crops and plant debris and maintain a heated greenhouse for 3-5 days to increase the metabolism of any soil-borne thrips pupae and starve them out. Wash greenhouse structures with hot water and detergent.

• Cover or screen greenhouse openings to exclude windborne pests

• Use care that pests do not enter greenhouses through vents, on clothes, or on tools

• Wash or freeze coveralls or tools overnight to help kill pests