Brown marmorated stink bug – adult CC-BY 2.0 Katja Schulz

Stink bug, Brown marmorated Halyomorpha halys (Stål)

PESTS

Hosts

Life Cycle

Identification

Feeding Damage

Field corn and soybean are preferred field crop hosts for nymphs and adults. Infestations have been reported on rape, pea, sunflower and cereals in the USA. Also attacks tree fruits, berries, vegetables and many ornamental trees and shrubs. Plants with fruiting bodies, buds, or pods are most attractive to adults for feeding and egg-laying. Not known to be established on the Prairies but detected in the BC Southern Interior in 2016. Present in Ontario and Quebec, and throughout the U.S.

MATURE NYMPHS: Brownish-red shield-shaped 12 mm long body with white markings on the exposed abdomen (no wings present) and faint white banding on legs. Eyes are a deep red. There are two white bands on each antenna. There are two white bands on each antenna. Small spines are present on the femurs and sides of the pronotum in later instars (3rd to 5th); a single spine is present in front of each eye.

ADULTS AND NYMPHS: Extracts plant fluids by piercing and sucking developing seeds with mouth parts. In soybean, the damage appears as shrivelled seeds and flattened pods. In corn, damaged kernels are discoloured and shrunken, similar to wheat. In late summer to early fall, infested soybean plants can display a “stay green” syndrome due to a delay in senescence. Most feeding damage occurs in the outer 10-12 m of crop as a result of adult immigration. Adults are also a nuisance in the spring when they congregate on buildings before dispersing and also because of the disagreeable ‘stink’ when squashed.

Hemiptera: Heteroptera

ADULTS: Stout, shield-shaped, 13-17 mm long mottled brownish grey body with alternating brown and white markings along the edge of the abdomen extending beyond the winds. There are two distinctive white bands on each antenna. Legs are also mottled brownish-grey with faint white banding. Underside of body somewhat whitish in colour. The “shoulders” of the pronotum (triangular body section behind head) lack spines

Adults overwinter in buildings and other protected locations that they emerge from in mid- to late spring. About 2 weeks later, females mate and disperse to lay from 200 to 400 white barrelshaped eggs in clusters of 20-30 eggs on the undersides of host plant leaves. Eggs hatch in 4-5 days. Because the egg-laying period is so long, all five nymphal instars and adults are present throughout the summer. Nymphs mature in about 5 weeks depending on temperature. New adults begin seeking suitable overwintering sites in late summer. Only one generation is expected per year.

Brown marmorated stink bug – nymph CC 2.0-BY Katja Schulz

Descriptions of Field Crop Pests

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Similar Species

Stink bug, Brown marmorated (continued)

There are many species of native stink bugs that may occasionally visit soybean and field corn crops, especially towards the end of the summer when native host plants die off. Examples are brown stink bugs (Euchistus servus Say), consperse stink bugs (E. consperus Rolston and related species), and rough stink bugs (Brochymena spp.). However, these and other stink bug species do not have the white bands on their antennae nor do they congregate on buildings in the spring like boxelder bugs (Boisea spp.) and the western conifer seed bug (Leptoglossus accidentalis (Barber)).

Hemiptera: Heteroptera

Monitoring/Scouting

Use sweep nets to sample the margins (especially nearest to buildings and woodlots) of host crops for adults and nymphs. For soybean, sample during the R4 (fully elongated pods) to R6 (fully developed seed). For corn, examine crop margins during ear formations stages R3 and R4. Collect and store any suspect stink bug specimens for examination by specialists. Sample wheat during the milk to soft dough stages. Researchers have identified an aggregation pheromone which will aid in earlier detection of this pest.

Economic Threshold

None established for corn, soybean, or wheat.

Management Options BIOLOGICAL: Surveys in the US revealed several species of native predatory insects and parasitoids attack this pest. Efforts are underway to evaluate Asian parasitoids and combine with field insectaries for native natural enemies to provide a biological control component. Brown Marmorated Stink Bug - numphs and eggs CC 3.0-BY David R. Lance, USDA APHIS PPQ, Bugwood.org

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CULTURAL: None developed yet. CHEMICAL: Control products are registered for control or suppression on corn, cereals, and dry peas. Check the labels for approved crops.

Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Management Field Guide

Field Crop and Forage Pests and their Natural Enemies in Western Canada IDENTIFICATION AND MANAGEMENT FIELD GUIDE

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