What has made this diamondback moth appear white and fuzzy?
This diamondback moth is covered in a fungus called Beauveria bassiana. Beauveria is an entomopathogenic (meaning it develops on insects), soil dwelling fungi. This beneficial fungus is native to the US and affects at least 700 species of insects. Aerial spores of the fungus land on host insects and if environmental conditions are conducive (warm and humid), the spores germinate and infect the host. Killing and colonizing the host may take anywhere from 3 days to 4 weeks, depending on the insect.
Beauveria was discovered nearly 200 years ago has been used to make bioinsecticides for years. Their effectiveness is variable and depends greatly on the weather conditions. In addition to warm, humid conditions, Beauveria products work best when applied on cloudy days or close to dark, as UV rays can quickly kill spores. Some Beauveria products include BoteGHA, BotaniGuard, and Mycotrol. Read more about Beauveria bassiana here.
This week’s question is from Justin Ballew, Extension Fruit and Vegetable Research Associate.
The South Carolina Grower 