|
To effectively control damage to your cabbage and other crucifer crops, you must first know your enemy. The cabbage worm moth, (Trichoplusia ni) is found throughout the United States, Canada and Mexico where ever crucifers are cultivated. They seem to overwinter mainly mostly in the southern most parts of the United States. Their life cycle seems to be somewhat erratic as there are years when there are many and other years there are very few. The reasons for which are still not completely understood. The adult cabbage butterfly is white with one to four black spots on the wings; they are often seen fluttering around the fields. The whitish, rocket-shaped eggs are laid singly on the undersides of leaves. The cabbage worm is active throughout the year in California.
The cabbage looper feeds on a wide variety of cultivated plants and weeds. As the common name implies, it feeds readily on crucifers, and has been reported damaging broccoli, cabbage, cauliflower, Chinese cabbage, collards, kale, mustard, radish, rutabaga, turnip, and watercress. Other vegetable crops injured include beet, cantaloupe, celery, cucumber, lima bean, lettuce, parsnip, pea, pepper, potato, snap bean, spinach, squash, sweet potato, tomato, and watermelon. Additional hosts are flower crops such as chrysanthemum, hollyhock, snapdragon, and sweet pea, and field crops such as cotton and tobacco.
Cabbage looper larvae damage plants by chewing holes in leaves. Smaller larvae remain on the lower leaf surface, while larger larvae produce larger holes throughout the leaf. In addition to feeding on the wrapper leaves of cabbage, larvae may bore into the developing head. For large scale growers the losses due to cabbage moth infestation is due to damage to the marketed parts of the plant.
Methods of prevention and treatment include the use of Dipel ( Bacillus thuringiensis ) is has been used an as organic treatment successfully for many years. The virus is specific for feeding worms. It has the additional benefit of being non-toxic to humans and beneficial insects. Also consider covering newly planted crops with light weight, porous row covers, making it impossible for the moth to lay it eggs.
Natural enemies can assist significantly in the control of imported cabbageworms. Important parasites include the pupal parasite Pteromalus puparum; the larval parasites Apanteles glomeratus, Microplitis plutella, and several tachinid flies; and egg parasites in the Trichogramma genus. Viruses and bacterial diseases are also sometimes important control factors in the field.
There are also varieties of certain cultivars that have been developed to be highly resistant to the moth.
|
Author Bio Box: Catherine Smith
Please visit me on my site at: http://www.helium.com
Didn't really find what you were looking for?
|
|
|
| |
|
|
![[Valid RSS feed]](images/rss.gif "Subscribe to our XML Feed for RSS")
(Read 100+ times)
