Monitoring and Integrated Pest Management of the invasive Brown Marmorated Stink Bug in fruits and vegetables

Published: March 17, 2017

Credit: Steven Valley, Oregon Department of Agriculture, Bugwood.org

The invasive Brown Marmorated Stink Bug (BMSB), Halyomorpha halys, [picture on the side- please cite source] is currently distributed in 43 US states and 4 Canadian provinces. It is a severe agricultural pest in 9 states (largely in the Mid-Atlantic) and a nuisance problem in 21 others.

Distribution of the Brown Marmorated Stink Bug in the USA as of 1.3.2017
Credit: http://www.stopbmsb.org/where-is-bmsb/state-by-state/

BMSB is considered to be a landscape-level threat. This means that adults frequently switch between cropped land (agronomic crops, fruits, vegetables, ornamentals) and wooded habitats. This article provides an update on monitoring and management of BMSB in specialty crops. Information provided here is summarized. The STOP Brown Marmorated Stink Bug website (http://www.stopbmsb.org) has been setup to provide current and relevant information on this pest.

BMSB has been reported to be in Missouri since 2013. While BMSB does not seem to have reached damaging populations yet, numbers have been increasing year by year as a result of breeding populations reported in Ferguson / St. Louis area in 2015, and the continued risk posed by dissemination via hitchhiking on vehicles. Therefore, farmers of specialty crops are encouraged to monitor for this invasive pest, especially if you live in St. Louis, Springfield, and Kansas City areas.

Where does BMSB spend the winter?
During the winter months BMSB enters a type of hibernation called diapause. During this time they do not feed and do not reproduce. Overwintering takes place in forested areas as well as inside houses and other buildings. In the spring, BMSB adults emerge from overwintering sites (houses, barns, storage buildings, and dead trees) and become active on nearby crops during warm sunny days. In the spring and throughout the summer, adults feed, mate, and lay eggs.

Agricultural crops being attacked by BMSB
Both adults and nymphs (immature stages) are known to cause feeding damage to crops. BMSM has a wide host range of over 300 plants. BMSB nymphs and adults feed by inserting their piercing-sucking mouthparts into fruit, nuts, seed pods, buds, leaves, and stems and appear to prefer plants bearing reproductive structures. Their mouthparts can penetrate very hard and thick tissue, such as the hazelnut hull. Feeding damage has been recorded in high value specialty crops including tree fruit (apples, peaches, pears), small fruit (e.g., raspberries, blackberries), vegetables such as tomatoes, sweet peppers, sweet corn, as well as agronomic crops such as soybeans (Fig. 2). In one study, researchers in the Mid-Atlantic reported that sweet corn, okra, and bell pepper had significant higher abundances of BMSB adults and nymphs compared with green bean, eggplant, and tomato.

Specialty crops at risk to BMSB damage
Credit: http://www.stopbmsb.org/where-is-bmsb/crops-at-risk/

Integrated Pest Management of BMSB

IPM recommendations for BMSB in specialty crops such as orchard fruit, small fruit, and vegetables have been developed by researchers across the country. Summaries of specific options that have been developed as of August, 2016, for grapes, orchard crops, and vegetables, are available at: http://www.stopbmsb.org/managing-bmsb/management-by-crop

FREE BMSB Identification Kits!

Researchers collaborating in the StopBMSB.org project have made identification kits available at no cost.

The kit includes one BMSB specimen in a bottle, stink bug ID guide, among other materials.

Click here to request your BMSB ID kit

Pest identification is key to IPM

I. ECONOMIC THRESHOLDS.
An economic threshold is basically the density of the pest triggering a control method, usually insecticides. If left untreated, economic losses due to pest damage may occur.

In specialty crops such as apples, researchers in West Virginia and Maryland have just developed a provisional threshold of 10 BMSB accumulated in one pheromone-baited trap located within the orchard or at the orchard border. Once this threshold is reached two alternate-row-middle sprays with 7 days between reduced the number of BMSB-targeted sprays while maintaining good control.

II. MONITORING
Commercially available traps and pheromone lures for BMSB monitoring provide valuable information on presence/absence of BMSB and also help to decide if insecticide treatments are needed to manage this pest. Ag-Bio, Inc. (http://www.agbio-inc.com), Great Lakes IPM (http://www.greatlakesipm.com), Trece, Inc. (http://www.trece.com) and Sterling International are some of the companies that sell monitoring systems for BMSB.

Black pyramid trap

Black pyramid traps. Stink bugs, including BMSB, are visually attracted to tree silhouettes. The trap recommended for monitoring is a black pyramidal trap, which represents trunk mimic, coupled with a capturing device. Researchers are trying to assess whether yellow sticky cards, which are easier to deploy, can be used for monitoring purposes.

Pheromone lures: Various companies are now marketing the male-produced aggregation pheromone of BMSB. Research has shown than when this pheromone lure is combined with another lure termed 'MDT lure' which is also commercially available, the result is increased response by BMSB adults and nymphs, thereby increasing the efficacy of monitoring traps.
The pheromone lure that is being used in Missouri is called "Stink Bug Xtra Combo - Broad Spectrum 5-7 week lure". It has been reported to attract multiple stink bug species such as Brown, BMSB, Conchuela, Consperse, Dusky, Green (Acrosternum), Harlequin, and Red Shouldered stink bugs. Therefore, efforts need to me made to correctly distinguish BMSB from other similarly-looking stink bugs.

When should I start monitoring for BMSB? Learning about the life cycle of insect pests is important to design effective IPM tools and strategies, including timing of monitoring. BMSB spend the winter as adults. After emerging from overwintering sites in May and June, BMSB adults begin mating and laying eggs on various host plants. Monitoring for BMSB can start in late-May, and needs to continue until early- or mid-October.

III. CHEMICAL CONTROL Insecticide sprays is the most effective control method for BMSB. It is important to select effective insecticides given that adult BMSB are hard to kill. Whenever possible, target the nymph stage, as nymphs are more sensitive to insecticides than adults. While insecticide recommendations vary according to availability on different crops, Actara, Brigade, Danitol, Mustang Maxx, and Lannate have shown good efficacy in trials; however, multiple applications may be needed with reinfestation. Specific insecticide recommendations can be found in the production guide for the various types of crops:

Tree-fruit and small fruit
Midwest Fruit Pest Management Guide 2017:
https://ag.purdue.edu/hla/Hort/Documents/ID-465.pdf 

Vegetables
Midwest Vegetable Production Guide for Commercial Growers 2017: https://ag.purdue.edu/btny/midwest-vegetable-guide/Pages/default.aspx

ALWAYS follow label instructions and safety procedures, and check to make sure the chemical you are using is registered for use in your crop.

Notes on insecticide application:

• The overwintering generation of BMSB tends to be more susceptible to insecticides than the summer generation. Therefore, products with the best effectiveness against this pest should be used later in the season
• Insecticides should be rotated among products in different classes with different modes of action to delay the onset of resistance to pesticides.

IV. CULTURAL CONTROL
The goal of cultural control is to make the crop environment less suitable for insect pests or to manipulate the environment in such a way that insects are less likely to arrive on the cash crop. Most of the time, cultural control is used as a preventative measure. Research is being conducted in this area and no promising tactics have been identified, except for trap cropping.

Trap cropping is a behaviorally-based IPM method involving planting very attractive plants next to a higher value crop so as to congregate the pest in trap crops where they can be easily attacked by natural enemies and/or killed by insecticides. Recent research with BMSB has shown that a trap crop mixture composed of sorghum and sunflower may be an effective management tool for BMSB. For organic systems, given the lack of effectiveness of most organic (OMRI-listed) insecticides, then flaming and vacuuming can be used to kill the arriving pests. To access a webinar on organic management options for BMSB including trap cropping click here: http://articles.extension.org/pages/67200/brown-marmorated-stink-bugs:-invasion-biology-monitoring-and-management-webinar.

References
Nielsen, A.L., Dively, G., Pote, J.M., Zinati, G., and Mathews, C. 2016. Identifying a Potential Trap Crop for a Novel Insect Pest, Halyomorpha halys (Hemiptera: Pentatomidae), in Organic Farms. Environmental Entomology. 45: 472-478. Abstract available at: https://www.ncbi.nlm.nih.gov/pubmed/26916518.

Piñero, J.C. and Houseman, R. 2016. Brown Marmorated Stink Bugs in Homes. University of Missouri IPM program. Newsletter article available at: https://ipm.missouri.edu/meg/2016/10/Brown_Marmorated_Stink_Bugs_in_homes.

Piñero, J.C. 2015. Presence of breeding populations of the invasive Brown Marmorated Stink Bug in Missouri. Missouri Produce Growers Bulletin. Available at: https://ipm.missouri.edu/meg/archive/2015/v21n10.pdf.

Quarles, W. 2014. IPM for the Brown Marmorated Stink Bug. The IPM Practitioner. 34(3-4). Available at: http://www.birc.org/IPMPJune2014.pdf.

Stop brown marmorated stink bug. Available at: http://www.stopbmsb.org.

Weber, D.C, Leskey, T.C., Walsh, G.C., and Khrimian, A. 2014. Synergy of Aggregation Pheromone With Methyl (E,E,Z)-2,4,6-Decatrienoate in Attraction of Halyomorpha halys (Hemiptera: Pentatomidae). Journal of Economic Entomology. 107: 1061-1068. Abstract available at: https://www.ncbi.nlm.nih.gov/pubmed/25026665.