![The Brown Marmorated Stink Bug (BMSB).](https://dtrr88ph77n37.cloudfront.net/s3fs-public/styles/medium/public/2022-05/516_OWENSTINK1.jpg?itok=KWfl6lCM)
Among the things we should be watching in the U.S. right now is the agriculture sector’s response to a nasty insect called the Brown Marmorated Stink Bug (BMSB). It’s taken hold there, and is poised to be a threat for horticultural producers and other farmers in our country, too.
BMSB, identifiable by its marbled or marmorated brown appearance, shield shape and two white bands on each antenna, will feed on most anything, including ornamentals, fruit and cash crops. A BMSB integrated pest management working group, led by the United States Department of Agriculture and involving entomology experts from major U.S. universities, is trying to help producers defend crops against this invader.
The group has created a superb website with management recommendations for producers. Researchers in Ontario are participating in this working group, as part of the coordinated BMSB research and outreach activity from the University of Guelph, the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) and Agriculture and Agri-Food Canada.
“We are learning as much as we can from the ongoing research in the U.S. before BMSB becomes an economic pest in Ontario,” says Hannah Fraser, OMAFRA’s entomology horticulture program lead.
In the states, BMSB has become a direct pest of many fruits and vegetables, causing problems that render the affected crop unmarketable. BMSB nymphs and adults injure vegetables by inserting their piercing-sucking feeding stylets into fruit, pods, buds, leaves, and stems. The time of the season when feeding occurs influences the type and appearance of crop injury, but generally, crops are most attractive to these insects during fruit set and crop maturation.
Research by the American working group shows BMSB activity is found in a wide variety of crops. For example, it says, sweet corn and edible soybeans can incur extremely high densities of bugs during the kernel or seed development periods. Okra and bell pepper are preferred host plants for the majority of the growing season and for reproduction. Green beans, tomatoes and eggplant also appear to support reproductive development of BMSB. Sweet corn, green beans, bell peppers and tomatoes are very susceptible to feeding injury. As well, asparagus and Swiss chard may be regularly attacked by BMSB.
Fraser says a big challenge here is that BMSB is a new pest to Ontario. Based on survey work and confirmed homeowner reports, OMAFRA believes the insect is already established in many parts of southern Ontario, along a corridor from Windsor to Ottawa, where it moved to from the northeast U.S. Five established (breeding) populations were confirmed in the corridor last year, but more are suspected.
The biology of this insect further makes management a challenge, says Fraser. BMSB is called a “landscape-level” pest with a high capacity for dispersal. That means it will move between hosts such as landscape plants and crops throughout the growing season. Population pressure is not uniform, and fluctuates during the growing season.
Action thresholds for BMSB are still under development for most horticultural crops. Many of the recommended management strategies are considered provisional.
This spring and summer, Ontario producers and crop consultants are being asked to assist with a trapping program, to help monitor the BMSB’s appearance throughout the province. The trapping program is part of a bigger effort to track the BMSB’s advance, and control it.
“We don’t want growers to miss the early signs that BMSB is in their crops,” says Fraser. “We want them to start thinking about BMSB, and using traps may be a way to get early adopters on board with adding BMSB to regular scouting.”
Fraser says early detection is vital for control, and that scouting for the insect on host plants is the best way to find it. The trapping program, which she expects to involve about 40 producers and consultants, is meant to raise awareness and provide insect counts that can be used for determining thresholds for control. Traps should be set up next month.
Producers interested in discussing the trapping program can contact Fraser at hannah.fraser@ontario.ca. But everyone should be scouting, and keeping an eye out for this bug’s spread.