The brown marmorated stink bug hitchhikes into 40 states
Squash a brown marmorated stink bug (BMSB), and your nose will soon smell a waft of fragrance akin to dirty socks. Worse yet, this stinky pest is beginning to raise a ruckus in some corn and soybean fields.
While the heaviest populations are found in the mid-Atlantic region, the BMSB now infests row crops, fruits and vegetables in at least 40 states. A native of East Asia, the bug was first identified in Pennsylvania fields in the late 1990s.
"They’re strong fliers with the ability to hitchhike," explains Paula Davis, DuPont Pioneer senior manager for insect and disease resistance traits.
Adult BMSB are about 3⁄4" long and have a shield-like shape. The term "marmorated" means marbled, which describes the mottled color on the back of the adult pest. Both nymphs and adults can be distinguished from other stink bugs by whitish bands on their antennae.
Voracious appetites. The BMSB poses a threat to about $21 billion worth of crops in the U.S. on an annual basis.
In soybeans, the BMSB feeds on soybean seeds through the pod, say Erin Hodgson and Matt O’Neal, Iowa State University (ISU) entomologists.
"During seed formation, BMSB can puncture tissue and cause deformations. The seed coat can be damaged, and overall, the seeds will be smaller and shriveled as a result of feeding," they say. "There’s little it doesn’t attack with vigor, piercing and sucking leaves, stems, fruits and seeds."
To date, O’Neal says the Plant and Insect Diagnostic Clinic at ISU has confirmed BMSBs in 10 Iowa counties. He does not anticipate a widespread problem in that state for 2014.
Other parts of the country are not as fortunate. Soybean growers in Maryland have had delayed maturity and yield losses of more than 50% at field edges due to BMSB, Davis says. Soybean farmers in other mid-Atlantic states have also experienced significant yield losses to the pest.
Sweet corn and field corn are also on the pest’s menu. BMSB injury can increase the potential for corn ear mold and damage seed quality.
Fight back. Controlling BMSB is complicated by the fact that the pest survives the winter as an adult by entering houses and structures. Plus, both nymphs and adults feed on host plants.
BMSB migrate from wooded areas and hedgerows into cornfields, says John Tooker, Pennsylvania State University Extension entomologist. "First, scout for populations in corn fields along margins with woods before exploring other corn fields. Later in the season, closely watch soybean fields along wood margins," he says.
Use a sweep net to evaluate BMSB numbers in soybeans. Ames Herbert, Virginia Polytechnic Institute and State University Extension entomologist, recommends spraying if there are five or six stink bugs on the plants surrounding you in all directions.
Farmers can learn more about this new pest at www.stopbmsb.org.
You can e-mail Rhonda Brooks at firstname.lastname@example.org.
- February 2014