Mid-South survey and biological feeding of Tennessee brown marmorated stink bug's potential to vector mycotoxin producing fungi

The brown marmorated stink bug (BMSB), Halyomorpha hays (Stål), is an invasive species native to Asia that was first introduced to the US in the mid-1990s. BMSBs feed on field and vegetable crops, orchards and ornamentals during the growing season and enter diapause in homes during the winter. Being highly polyphagous, it is hypothesized that BMSBs can carry toxigenic fungi between food sources, and ultimately increase mycotoxin loads in crops. During the summer of 2022, wild Tennessee populations of BMSBs were collected, surfaced sterilized, placed into individual modified feeding chambers lined with filter paper and stored in an incubator with optimal feeding conditions. BMSBs were allowed to feed on a 20% sucrose “purge” for 7 days after which BMSBs were re-sterilized, placed into new chambers with filter papers, and fed on their randomly assigned treatments for 14 days. Each filter paper and dissected stink bugs were placed onto either selective or non-selective media and allowed to grow for 7 days. Each plate was inspected to see if the BMSBs fed, if they passed the treatments through their digestive systems, and if the treatments grew out on media from the filter papers and BMSBs digestive tract. This experiment will be paired with a Mid-South survey to determine if the same phenomenon is occurring outside of Tennessee. This information is critical for determining if BMSBs can pass toxigenic fungi through their digestive system, predicting mycotoxin presence from season to season, and what can be done to potentially reduce mycotoxin loads before harvest.