This tool is part of the Citrus Resource

Citrus Pests

 

Cabbage looper

 

Scientific name

 

Trichoplusia ni (Lepidoptera: Noctuidae)

Similar species

 

soybean looper, Pseudoplusia includens

The soybean looper can be differentiated from the cabbage looper using wing characteristics. The forewing of the cabbage looper has centrally-positioned, silvery-white spots that resemble a "V" or "figure 8". In contrast, the forewing of the soybean looper has two centrally positioned brown spots that have a thick, silvery white outline.

Distribution

 

United States: Widespread almost everywhere host plants are grown; overwinters in Arizona, Florida, Hawaii, and Texas.

Worldwide: Canada, Central America, Mexico, and South America.

Native to North America.

Diagnostic characteristics

 
Adults
  • Mottled dark gray brown in color with silvery white spots located centrally on forewing.
  • White spot on forewing resembles a "V" or "figure 8."
  • Hindwings light brown at the base and dark brown distally.
  • Wing span of 33 - 38 mm (1.5 in.).
Pupae
  • Pupa initially green, but turns dark brown before pupation.
  • 19 mm (0.75 in.) in length.
Larvae
  • Number of larval instars varies from four to seven.
  • Young larvae are white or green and have hairs that decrease as the larvae matures.
  • Mature larvae are green with a white stripe on both sides of the caterpillar.
  • 30.5 - 40.6 mm (1.2 - 1.6 in.) in length at maturity.
Eggs
  • Eggs are hemispherical in shape with the flat side fixed to foliage.
  • Eggs are usually deposited singly but can be in clusters of 6 - 7.
  • Eggs are yellowish-white to light green in color.
  • Eggs have longitudinal ridges.
  • 0.6 mm (0.02 in.) in diameter and 0.4mm (0.015 in.) in height.

Hosts

 
Citrus hosts

All Citrus species and their hybrids.

Non-citrus hosts

Broad host range, including weeds as well as vegetable, field, and flower crops. A partial list includes:

  • all cruciferous vegetables, Brassica oleracea
  • bean, Phaseolus vulgaris
  • Celery, Apium graveolens
  • chrysanthemum, Chrysanthemum spp.
  • cotton, Gossypium hirsutum
  • dandelion, Taraxacum officinale
  • dock, Rumex crispus
  • lambsquarters, Chenopodium album
  • lettuce, Lactuca sativa
  • melon, Cucumis spp.
  • pepper, Piper nigra
  • potato, Solanum tuberosum
  • soybean, Glycine max
  • squash, Cucurbita spp.
  • sweet potato, Ipomoea batatas
  • tobacco, Nicotiana tabacum
  • tomato, Solanum lycopersicum
  • watermelon, Citrullus lanatus
  • wild lettuce, Lactuca spp.

Host damage

 
Flowers
  • Feeds on blossoms.
Fruits
  • Feeds on young fruit.
Leaves
  • Prefer to feed on new growth flushes.
  • First three larval instars feed on the lower leaf surface, leaving the upper leaf surface intact.
  • Fourth and fifth instars chew large holes through foliage and can consume entire leaf.
  • Larvae can consume 3 times their weight in plant material daily.

Biology

 

Adults are nocturnal but can also be found at dusk and will live for 10 - 12 days. A female will lay 300 - 600 eggs in her lifetime. Eggs hatch in 3 - 4 days. Only larvae are responsible for damage to plants. There are 4 - 7 larval instars. They are referred to as loopers because they walk in a "looping" manner. Larvae pupate in soil or cocoons on host plant fruit and leaves. It takes 18 - 25 days for development from eggs to adult. These moths are sexually dimorphic, and the males have tufts of gold hair at the tip of abdomen. There are 2 - 7 overlapping generations per year, depending on temperature. Year round activity and reproduction occurs south of Orlando, Florida.

Comments

 

Not considered a major pest of citrus and rarely require treatment.

References

 

University of California, IPMOnline. 2008. UC IPM Pest Management Guidelines: Citrus. (http://www.ipm.ucdavis.edu/PMG/r107302211.html).

Capinera, J.L. 2005. Featured creatures fact sheet: Trichoplusia ni (Hübner). Publication EENY-116. University of Florida. (http://entnemdept.ufl.edu/creatures/veg/leaf/cabbage_looper.htm).

Authors

 

Weeks, J.A., A.C. Hodges, and N.C. Leppla

 

Citrus Pests
Content last updated June, 2012
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