Friday, January 9, 2009

Ladybird Beetle: Natural pest control for plant eaters.
This is lady beetle or ladybird beetle. Most species of ladybird beetles are among our most beneficial insects. This fact and their attractive appearance have contributed to the generally good opinion of them held by most people. And with the same reason French call them “creatures of the good god”. There are more than 4000 species found worldwide. Most species can be identified by the pattern of spots on their wing covers.
Like all beetles, the ladybird beetle has a complete metamorphosis with distinct egg, larval, pupal and adult stages. Usually the life cycle from egg to adult requires about three to four weeks. Tiny, yellow oval eggs are laid upright in clusters of 10 to 50 on undersides of leaves. Eggs hatch in 3 to 5 days, and larva feed on aphids or other insects for two to three weeks. The larva pupate then the adult emerges in 7 to 10 days.
Ladybird beetles, both adult and larva, are known primarily as predators of aphids, but they prey also on many other pests such as soft scale insects, mealy bugs and spider mites etc. One larva will eat 400 medium size aphids during its development to the pupal stage. An adult will eat more than 5000 aphids in its lifetime. In western countries dealers collect these insects and sell. The reason for this is that the beetles congregate in huge numbers in colonies or aggregate in the same site year after year.
Ladybird beetles have some interesting means of protection. Their red or orange and black coloration warns birds that they would not make very tasty meal. Birds learn that insects that are red and black or yellow and black usually sting or taste bad and hence they leave such insects alone. Ladybird beetles, of course, can’t sting but do taste bad. They also will “play dead” when in danger. Many predators will not eat an insect that doesn’t move. Also, ladybird beetles probably produce a bad smelling odor, perhaps by way of a fluid from joints in the legs, which may help to protect them.
Yuwaraj Gurjar.

No comments:

Post a Comment