Adult
Larva
Cabbage looper (Trichoplusia ni)
Cabbage loopers are catepillars of the moth Trichoplusia ni.
These caterpillars are considered to be a pest species on cruciferous
plants, such as broccoli, cauliflower, and cabbage, and are easily
reared from egg to adult in about three weeks.
Availability: You will be able to follow your lepidopteran
through egg, five larval instars, pupal and adult stages over the
course of 3-4 weeks. To do so, we will provide you with eggs.
Unfortunately, eggs are available only periodically from our colonies
about once a month.
After you have a cage (a small screw-top jar works fine) and supplies
(food) ready, contact Liz (eegraham@life.uiuc.edu)
to schedule a pickup time (right after class is convenient). We will
provide you a piece of cheesecloth covered with a dozen or so eggs and
enough artificial diet for the neonates (newly hatched larvae) to live
off for a few days. Neonates are tiny when they hatch (about the size
of a period) and will starve to death within a few hours if not
transferred to diet. To avoid this, we suggest that you keep the eggs
in the transfer container and allow the larvae to feed on the
artificial diet for a day or two. Put the diet cup upside down (with
the diet at the top) -- cabbage loopers prefer to feed on the underside
of plants.
Housing: These caterpillars can be easily reared through adult
emergence in a small plastic or glass container. Use a container that
you can make observations through. The main challenge is to retain
enough moisture, but to avoid allowing the early instars to escape or
suffocating later instars. The best containers are ones with a
loosely-fitted lid or screw top. Keep the lid tight for the first few
instars. When the larva has completed three molts, either loosen the
lid or poke a few tiny holes in the lid. Periodically remove frass to
avoid disease. The loopers can remain in this container during the
larval stages.
When your insect pupates, transfer it to the adult container.
Adults require more space to move about and fly than the larvae.
Minimally, an adult requires a container that is about a pint size or
larger. We use plastic ice cream buckets sealed with a cheesecloth lid.
Common containers that have worked in the past include medium size
jars, yogurt containers, and juice containers. Be sure to clean your
container first! If you do not have a lid, you can use a piece of cloth
or paper towel and a large rubber band to keep the moth in the
container. We will also set you up with a small vial to provide an
artificial nectar source for the adults, as well as instructions.
Food: Part of the challenge of raising herbivores is providing
them with fresh, healthy food. This species can be reared on
the artificial diet provided for a few days. However, you should try to
rear your caterpillars on plant material. Cabbage loopers develop best
on fresh cruciferous plants, such as
broccoli, cauliflower, cabbage, and brussel sprouts, and they prefer to
feed on leafy material.
Some important guidelines:
Use only fresh organic vegetables or leaves when feeding your
caterpillars. Non-organic vegetables often contain traces of
insecticides which may be specifically directed against your
caterpillar (these are pest species)!
Replace food daily to avoid disease and microbial spoiling. Use small,
whole portions.
Keep the unused vegetable portions in the refridgerator to limit
spoiling.
For your own ease, try to use food that will not spoil rapidly.
Keep in mind that all cruciferous plants develop strong odors as they
decay. Why don't we see canned broccoli? Because it smells like
sauerkraut.
Pupae do not need to eat food. Adults require nectar or a sugar water
source to survive. Adults can be fed on a 10% honey water solution (1
part honey dissolved in 9 parts water) in a glass vial stuffed with a
cotton plug (talk to us - we will provide this in the start-up kit).
The honey water and cotton plug should be changed daily to avoid
microbial contamination.