Colorado potato beetle

The Colorado potato beetle, Leptinotarsa decemlineata, is a beetle. It is sometimes just called the Colorado beetle. It is one of the worst potato pests in the world.  

The beetle is notable for its ability to resist pesticides. Over the last 50 years it has become resistant to 52 chemical compounds used in insecticides, including cyanide. Plant pests: The biggest threats to food security? BBC News Science & Environment  However, not every population is resistant to every chemical. Alyokhin A. et al. 2008. Colorado potato beetle resistance to insecticides. American Journal of Potato Research 85: 395–413. 

The Colorado beetle first lived in the southwest United States and northern Mexico. Now it lives in most of North America and also in Europe and Asia.

What it eats
The Colorado potato beetle now eats cultivated potato plants. Both larvae and adults eat the leaves and strip the plant down to a skeleton. They may also attack tomato and eggplants. There can be so many Colorado potato beetles in potato farms that they destroy the potatoes.

 Defence 
Because the beetle rapidly evolves resistance to chemicals, the best defence may be biological control. A ground beetle, Lebia grandis is a predator of the eggs and larvae, and its larvae are parasitoids of the Colorado beetle's pupae. 

Beauveria bassiana (Hyphomycetes) is a pathogenic fungus that infects many insects, including the Colorado beetle. It is probably the most widely used natural enemy of the Colorado beetle. There are commercial formulations that can be applied using a pesticide sprayer. 


 Origins 
The Colorado potato beetle did not always eat potato plants. This is because potatoes came from South America, not near the beetle's original range. Before people brought potatoes to North America, the Colorado beetle ate a plant called buffalo-bur.

References

Category:Chrysomelidae
Category:Agricultural pests