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Posts Tagged: brown marmorated stink bug

UC and CDFA researchers make progress in fight against exotic brown marmorated stink bugs

Brown marmorated stink bugs (Photo: USDA)
Scientists are rearing tiny Asian wasps in quarantine and evaluating whether they can be released in California to battle brown marmorated stink bug (BMSB), an invasive pest that poses a serious threat to the state's $54 billion agricultural industry, they reported in the current issue of California Agriculture journal.

The wasp, Trissolcus japonicus, has scientists feeling hopeful, said Chuck Ingels, UC Cooperative Extension advisor in Sacramento County and one of the 10 authors of the article. Ingels and a team of UC and California Department of Food and Agriculture scientists have been closely monitoring BMSB since large populations were found in downtown Sacramento in 2013.

“We hope T. japonicus will render BMSB a much lower threat, to where it might end up a background stinkbug,” Ingels said. “It all depends on how well the parasitoid adapts to our climate if we get to the point of releasing it.”

At the moment, BMSB has not caused significant damage to agricultural crops in California, but UC scientists want to be ready with solutions should it migrate into farms. BMSB – a native of China, Korea, Japan and Taiwan – made its way to the East Coast of the U.S. in the 1990s. By 2010, it caused millions of dollars in crop damages in apples, peaches and vegetables. The pest was first detected in California in 2002. It is now in urban communities in Siskiyou, Butte, Sutter, Yolo, Sacramento, San Joaquin, Stanislaus, Santa Clara and Los Angeles counties.

In urban areas, the pest is a nuisance. Bugs aggregate in late summer on walls and trees, and then seek refuge in the winter inside homes, garages and other buildings. Massive aggregations of BMSB are a disturbing sight and emit a pungent cilantro-like odor. In restaurants, BMSB can alarm patrons when the insects are mistaken for cockroaches, potentially hurting the eatery's bottom line.

“Apartment managers complain that tenants are threatening to move out because of the stink bugs,” Ingels said. “It's an economic issue.”

But BMSB's potential for damage in commercial agricultural crops portends a much greater economic threat. BMSB's host plant range of 170 species includes many valuable fruit, nut, vegetable and ornamental crops. In August and September of 2015, BMSB was found feeding on citrus, persimmons and apples in a Sacramento community garden. In July 2015, BMSB was found for the first time in traps placed close to citrus, kiwi and avocados in Los Angeles County backyards.

Already, several “generalist predators” have been observed feeding on BMSB – such as lacewings, mantids, earwigs, lady beetles, assassin bugs, pirate bugs, big-eyed bugs and spiders. Field research has also found that at least 12 North American species of stink bug egg parasites will lay eggs in BMSB egg masses.

A Trissolcus japonicus female readily parasitizes eggs of BMSB. (Photo: Jesus "Ricky" Lara)
However, because the local species may not be enough to provide adequate levels of population suppression, the researchers are interested in T. japonicus, a natural enemy of BMSB in its home range in China. The wasp can help to control populations of BMSB by laying its own eggs inside BMSB eggs. The researchers say finding and establishing a host-specific natural enemy may significantly increase control and prevent further economic problems.

“The introduction of a beneficial natural enemy like T. japonicus, which co-evolved with BMSB in China, increases our chances of successfully targeting and suppressing BMSB populations in the United States,” said Ricky Lara, a post-doctoral scholar at UC Riverside and lead author of the article. “In California, UC and CDFA researchers will continue to conduct the required safety evaluations with T. japonicus to deliver a cost-effective BMSB biological control program.”

Without being introduced by authorities, T. japonicus have been found in Maryland, Virginia and Vancouver, Wash., presumably having been accidentally introduced via parasitized BMSB eggs from Asia. DNA analyses determined that the T. japonicus collected in the field did not originate from the populations in quarantine, indicating that there have been no accidental escapes from these secure facilities.

The California research was funded with a grant from the CDFA Specialty Crop Block Grant Program, which was awarded to Charles Pickett, CDFA senior environmental scientist specializing in biological control, and Mark Hoddle, UC Cooperative Extension biological control specialist. Funding was also provided by the USDA Farm Bill, the California Pistachio Research Board, the Pear Pest Management Research Fund and the Consolidated Central Valley Table Grape Pest and Disease Control District.

Posted on Monday, February 29, 2016 at 8:49 AM

Invasive stink bugs found in Stanislaus County

Brown marmorated stink bugs continues to spread.
The brown marmorated stink bug (BMSB) has made its way to Stanislaus County, reported John Holland in the Modesto Bee. The invasive pest, introduced into the U.S. from Asia, has also been detected in San Joaquin, Sacramento, Yolo, Sutter, Butte, Santa Clara and Los Angeles counties.

The stink bugs pose a threat to a wide variety of plants, including home-grown and commercial ornamentals, fruits, vegetables and nuts, said Jhalendra Rijal, the area integrated pest management advisor with UC Agriculture and Natural Resources. Rijal is based at the UC Cooperative Extension office in Modesto.

BMSB was found in two Stanislaus County locations in recent weeks: outside a business at Kansas Avenue and Highway 99 in Modesto and outside the home of a pest control adviser in Turlock. Rijal said there have been no reports of BMSB in the county's farmland, but they could be out there.

"There is definitely potential for this pest, because it can feed on many host plants in agricultural and urban settings," he said. 

The Modesto Bee quoted the UC IPM Pest Note on brown marmorated stink bug in its article.

"An efficient way to collect stink bugs indoors is by sucking them up with a dry or wet vacuum," the Pest Note says. "The bugs will cause the collection canister or bag and other parts of the vacuum to give off an unpleasant stink bug odor, so some people dedicate a vacuum cleaner to stink bug capture only."

The pest note provides detailed information on monitoring for and managing stink bug infestations.

Posted on Thursday, August 6, 2015 at 8:53 AM

Brown marmorated stink bugs expected to have a 'banner year'

White stripes on the bug's antennae are a dead giveaway the insect is brown marmorated stink bug.
The California population of brown marmorated stink bugs, a pest introduced into the state from its native Asia, continues to spread and increase in and around Sacramento, said a UC Agriculture and Natural Resources (UC ANR) expert who appeared today on Capitol Public Radio's Insight program with Beth Ruyak.

Chuck Ingels, UC ANR Cooperative Extension advisor in Sacramento County, said BMSB was first spotted in 2013 in Sacramento and each year the numbers have grown. This year, the warm spring gave BMSB a head start, portending significant population growth in August and September 2015.

"We're very concerned about tree crops, tomatoes, peppers, corn, beans and other crops," Ingels said. On a bright note, he said California farms do not have forests surrounding them like farmers back East, where growers have been dealing with BMSB since the the mid-1990s. "BMSB is an arboreal species. They live in trees and then come into the farm. We're not sure how much of a problem it will be on farms here (in California)."

Ruyak asked whether any control solutions can be found in the pest's native territory or from farmers back East. 

"Growers are using pesticides back East," Ingels said. "There is a parasitoid from China that is under study in labs to see if they pose a problem for native stink bugs and other bugs."

One possible solution for dealing with the pests in gardens is planting sunflowers. Because BMSB are strongly attracted to sunflowers, they may draw the pests away from other crops and allow gardeners to monitor the BMSB presence. On the other hand, sunflowers may actually attract BMSB to the garden, where they could feed on vegetable crops.

BMSB feeds with a mouthpart called a "proboscis," stinging developing fruit 1/4 to 3/8 inch deep and sucking out its juices. As the fruit ripens, it hardens and deforms, becoming inedible.

Read more about BMSB, how to identify it, and methods to manage it around homes and gardens in the UC IPM Pest Note: Brown Marmorated Stink Bug.

Posted on Wednesday, July 8, 2015 at 11:18 AM

Nightmare in midtown: Brown marmorated stink bugs

A Sacramento report considers brown marmorated stink bug worthy of a Halloween creature feature.
A population of invasive brown marmorated stink bugs have settled in Sacramento's mid-town, a development that Sacramento Bee writer Debbie Arrington says is "worthy of a Halloween creature feature."

"Wow, I'm being overwhelmed with calls about brown marmorated stink bugs getting into people's home, as well as restaurants and businesses," said Chuck Ingels, UC Cooperative Extension advisor in Sacramento County. "It's that time of year again!"

When days get shorter and cooler, the BMSB start looking for a place to spend the winter. Frequently, that's inside homes and buildings.

Ingels told the reporter he is keeping track of the BMSB invasion. Residents are asked to fill in an online survey to report BMSB finds. For identification help, residents may deliver BMSB in a sealed plastic bag or container to the UCCE office, 4145 Branch Center Road, Sacramento, or they can email clear photos to cesacramento@ucanr.edu.

Ingels said fairly large populations of BMSB have been found in Citrus Heights near Auburn Boulevard and River Park north and west of CSU Sacramento.

"Most of the others are single finds," he said.

For more information on BMSB identification and management, read a Pest Note posted by the UC Integrated Pest Management program.

Posted on Monday, October 27, 2014 at 10:38 AM

Invasive pests of concern for California’s urban agriculture systems

Every year, California receives, on average, six new exotic invasive pests of concern; that's about one new pest every 60 days. These may be plants, insects or other arthropods, mollusks, plant pathogens such as fungi and bacteria, vertebrates, or any other organism not native to our state and with the capacity to negatively impact agriculture, urban environments and/or natural ecosystems. These invasive pests enter California on plant material and other biological substrates, as hitchhikers on trade goods and in ship ballast water, and sometimes even because of smuggling operations. Without the natural enemies that kept them in check in their native lands, they are free to reproduce and wreak havoc. Such pest invasions may then lead to destruction or alteration of habitat, loss of agricultural trade revenues, pronounced losses in agricultural production, and increases in pesticide applications.

The best way to combat such invasions may be through robust exclusion, inspection, early detection, and quarantine programs. Once established, they are best managed using classical and conservation biological control and the decision-making process of integrated pest management (IPM), described in detail in an earlier blog post. Urban agricultural environments are not immune to these invasions and may even be more at risk since urban environments contain many likely routes of introduction and have often been identified as point sources for invasive pests. In this article we will review the biology, ecology, and management of three recent pests that may increasingly be found in urban gardens and other urban ag environments.

Asian citrus psyllid and the huanglongbing pathogen: First found in Southern California in 2008, the Asian citrus psyllid (ACP), Diaphorina citri, feeds on citrus and related plants in the Rutaceae family, sucking sap and injecting toxins that distort new growth. Even worse, however, the psyllids can transmit an incurable citrus disease, huanglongbing (HLB) or citrus greening, from plant to plant. Currently, the psyllid's distribution is limited to urban Southern California and small parts of the citrus production areas in the San Joaquin Valley. The bacterial disease HLB is thankfully not established in California, but it has been detected (and eradicated) in urban Los Angeles County and intercepted recently at a port-of-entry in San Mateo County. If you grow citrus, make sure to check new growth during spring and fall to look for psyllid nymphs and the distinctive waxy tubules they excrete. Report any suspect finds to your County Agricultural Commissioner's office. Make sure to comply with the management tactics prescribed by these authorities; trees across the state depend on it. To learn more about ACP, HLB, management tactics, and other related topics please visit the following links: 

PESTNOTES - UC IPM Online: Asian Citrus Psyllid and Huanglongbing Disease

Center for Invasive Species Research: Asian Citrus Psyllid

UC scientists release a natural enemy of Asian citrus psyllid


Brown marmorated stink bug (BMSB): This large (5/8”) stink bug from eastern Asia has been an established pest in the eastern United States since 2001. Though it has been intercepted many times in California over the years, probably because of its ability to hitchhike on and in outdoor household items (such as patio furniture) and firewood, it has only recently (sometime between 2006 and 2013) become established in the state. The BMSB, Halyomorpha halys, is a key agricultural pest, reportedly attacking over 100 plant species using piercing mouthparts to suck juices and inject tissue-damaging enzymes. Damage is expected to be worst on pome fruits (apples, pears), stone fruits (peaches, nectarines), legumes, corn, tomatoes, and peppers. Stink bugs are known to aggregate in large numbers in fall, sometimes entering homes and other structures to escape harsh winter conditions. BMSB can be distinguished from several native stink bug species by two white bands on the antennae. The current distribution in California is unknown, so if you think you find BMSB you should contact your County Agricultural Commissioner's office to confirm and document its presence. To learn about BMSB identification and management, please visit the following links:

PEST NOTES - UC IPM Online: Brown Marmorated Stink Bug 

Pest Alert - UC IPM Online: Brown Marmorated Stink Bug

Center for Invasive Species Research: Brown Marmorated Stink Bug


Bagrada bug: This small (1/4”) relative of the BMSB, also called the painted bug, preferentially attacks many plants in the mustard family (Brassicaceae), including crops such as broccoli, Brussels sprouts, cabbage, and kale, as well as related ornamental plants such as sweet alyssum, stock, and candytuft. Native to Africa, bagrada bug was first found in urban southern California in 2008 and has been slowly moving up the coast and north within the Central Valley.  Most recently, the pests has become established within many urban gardens in the San Francisco Bay Area and in small farms in the Capay Valley. Damage is most severe on newly-planted seedlings; stunting and death are common when infestations are large. The brightly-colored (orange, black, and white) bugs are sometimes confused with the similarly-colored harlequin bug, a common American species, though these are three times larger and lack any white coloration. Similar to the BMSB, bagrada bugs may aggregate and enter structures and other protected areas during winter. As with the other invasive pests discussed, if you think you find bagrada bug in your area, then please alert your County Agricultural Commissioner's office, especially in areas where these insects have yet to be found. To learn more about bagrada bug identification and management, please visit the following links:

PEST NOTES - UC IPM Online: Bagrada Bug

Pest Alert - UC IPM Online: Bagrada Bug

Center for Invasive Species Research: Bagrada Bug

Posted on Thursday, September 25, 2014 at 1:36 PM
  • Author: Andrew M Sutherland, SF Bay Area Urban IPM Advisor

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