Strawberry blossom weevil - Anthonomus rubi
Effective: 05/11/2022
Taxonomic Position: Coleoptera : Curculionidae
Pest Type: Insects
Pest Code (NAPIS): INASUZA
These Approved Methods are appropriate for: 2024, 2023
Pest Information
CAPS Pest Datasheet: https://download.ceris.purdue.edu/file/4201
Pest Tracker: https://pesttracker.org/pest.php?code=INASUZA
Hosts Identified in the CAPS Host Matrix: Blackberry/Boysenberry/Raspberry; Strawberry
Human and Animal Pathogens Transmitted
Not known to transmit any human or animal pathogens.
Pest Pathogens and Organisms Vectored
Not known to vector any pathogens or other associated organisms but damage may lead to invasion by secondary pests.
Survey
Method Product / Instructions NAPIS Survey Method
Trap and Visual 49 - Vaned Plastic Bucket Trap - Green 6001 - General Trapping and Visual

Approved Lure(s)

NAPIS Code Product Name Dispenser Effectiveness Compound(s)
168 Anthonomus rubi Lure pending pending
Lure Attachment: Attaching lures to traps

IMPORTANT: Do not include lures for other target species in the trap when surveying for this target.

Survey Recommendations

The following are recommendations for executing the survey using the approved methods for pest surveillance. The recommendations are developed through literature review and consultation with subject matter experts.
SPECIAL NOTE: To complete a survey for this pest, you must perform both visual and trapping surveys.
Target Life Stage: Adult
Time of Year to Survey:
Surveys should be conducted at temperatures above 50°F when adults are active. Overwintering, unmated adults emerge in the spring and are active on hosts during warm, sunny weather. Adults feed on the young leaves of strawberry, blackberry, raspberry, and other host plants. In autumn, they feed on the ripening berries and on the pollen of certain wild plants.
Survey Site Selection
Visual and trapping surveys can be conducted in commercial strawberry, blackberry, or raspberry fields, or in areas with wild host plants. This weevil was often found in wild Himalayan blackberry hedges in British Columbia.
Survey Design

Surveyors should perform simultaneous visual and trapping surveys. Inspect host plants for severed or damaged buds and place traps in the soil to capture adults. Active collection of adults is optional (see below).

Visual Survey

Visually inspect host plants throughout the survey site for damaged or severed buds, especially in Himalayan blackberry.

Damaged emerging buds are a distinct sign of A. rubi early in the growing season in the western region of North America (west of the Rocky Mountains). The female weevil severs the closed green flower bud from the stalk after laying eggs inside it. Buds will either drop from the plant or hang partially attached. See the CAPS Pest Datasheet for images of damaged buds.

In addition to the required methods described above, surveyors can actively collect adults by either (1) shaking host plants and catching the falling insects in a cut-off milk jug or other container or (2) beat-sheeting host plants. Focus collection efforts on or near plants with signs of infestation. Because these methods can damage host plants, obtain permission from landowners or growers before attempting collection.

Trapping Survey

Deploy traps throughout the survey area. Partially bury traps in soil so that the top can be removed but the trap doesn"t blow away.

Sample Collection Instruction
After trapping or actively collecting specimens, place samples of adult A. rubi in vials of 70% ethanol for shipping and identification. Please see How To Submit Specimens To APHIS PPQ For Official Confirmation of a Preliminary Identification for more information.
Key Diagnostics or Identification

Approved Method(s)

ID/Diagnostic: Morphological
Final identification is through morphological analysis by an identifier.
Identification Resources
The Identification Technology Program (ITP) has a collection of identification resources at https://idtools.net/idAids/searchResults.cfm?searchString=rubi&searchType=1.
Mistaken Identities

Anthonomus rubi is similar to A. signatus, which is found in the United States east of the Rocky Mountains . Adults of the species appear different, while A. rubi is black, A. signatus is brownish-red with a large black spot on each elytra. However, an all-black color morph of A. signatus has been reported from British Colombia, Canada. The biology and hosts of the two pests are similar.

There are other similar looking Anthonomus species, including A. corvulus, A. nigrinus, and A. eugenii however, these species are found on different hosts than A. rubi and A. signatus. Anthonomus eugenii is found in the southern United States.

References

If you are unable to find a reference, contact STCAPS@usda.gov. See the CAPS Pest Datasheet for all references.