The compounds, called flavonoids, have an insecticidal effect on corn earworm larvae.
The compounds, called flavonoids, have an insecticidal effect on corn earworm larvae.
The corn earworm causes the loss of more than 76 million bushels of corn in the United States annually, and there is mounting evidence that increasingly extreme weather events and temperatures will exacerbate the damage done to agricultural output by insect pests. Responding to the threat, a team of researchers at Penn State has demonstrated that genetic lines of corn have inherent compounds that serve as insecticides, protecting them from the larvae that feed on them.
In findings recently published online ahead of the March issue of Plant Stress, the researchers reported that corn earworm larvae feeding on the silks, husks and kernels of corn lines containing high levels of flavonoids — chemicals that play essential roles in many biological processes and responses to environmental factors in plants — grow much more slowly and many die, compared to larva feeding on corn lines without flavonoids.
In addition to increased mortality and reduced body weight, larvae feeding on high-flavonoid corn lines developed a leaky-gut-like syndrome, the researchers found, suggesting involvement of microbiome changes in the larval gut. Moreover, the expression of gut health-related genes was changed in larvae consuming the flavonoid-rich husks.
Read more at Penn State
Image: The flavonoids that provide insecticide-like protection to some corn lines against corn earworm larvae also provide pigments to the plants that show up in the silks, husks and kernels. Pictured here are the lines used in the research. (Credit: Penn State)
