Add one more entry to corn’s list of abilities: helping to biologically control pests.
Already a source of food and biofuel, University of Florida researchers report in a new study that corn plants can help sustain populations of small, flying insects known as gall midges in order to control two spotted spider mites.
Spider mites are hard-to-manage, major pests of hundreds of ornamental and vegetable crops.
In the study, which is published in the current issue of Crop Protection, the highly mobile midge could find spider mites from more than 23 feet away and controlled more than 81 percent of spider mites on green beans in a greenhouse test.
The corn provides a supply of non-pest mites to feed gall midges when spider mite populations run low.
This is known as a banker plant system since the corn plant stores, or “banks,” extra prey for midges. And by using the midge to control spider mites, the system reduces the need for pesticides.
“Anything you can do to manage spider mites without using pesticides is going to be a major benefit,” said Lance Osborne, an entomologist with UF’s Institute of Food and Agricultural Sciences and co-author of the study. Osborne is based at the Mid-Florida Research and Education Center in Apopka.
Spider mites quickly build resistance to pesticides and become nearly impossible to control, Osborne said.
Growers interested in using this system may contact Osborne for more information by email at [email protected]  or by calling 407-884-2034, ext. 163.
The system was tested on green beans but could be applied to different greenhouse-grown crops, such as tomatoes.
Study co-authors include graduate assistant Yingfang Xiao, associate professor Jianjun Chen, lab technician Katherine Houben and research assistant Fabieli Irizarry — all with IFAS, and Cindy McKenzie, research entomologist with the U.S. Department of Agriculture in Fort Pierce.
The Environmental Protection Agency, the USDA Floriculture and Nursery Research Initiative and UF/IFAS funded the research.