Tuta absoluta (Meyrick): Tomato Leafminer

tomato-leafminer-5431766-photo-by-Marja-van-der-Straten-bugwood
California Pest Rating for
Tuta absoluta (Meyrick): Tomato Leafminer
Lepidoptera: Gelechiidae
Pest Rating:  A

PEST RATING PROFILE
Initiating Event:

A pest rating proposal is required to determine a permanent pest rating for Tuta absoluta (tomato leafminer).

History & Status:

BackgroundTuta absoluta is a moth that feeds on the leaves and fruit of solanaceous plants.  Known hosts include: Solanaceae: Capsicum annuum (pepper), Datura ferox (long spined thorn apple), Datura stramonium (Jimson weed), Lycium chilense (coralillo), Lycopersicum puberulum, Nicotiana glauca (tree tobacco), Nicotiana tabacum (tobacco), Phaseolus vulgaris (common bean), Physalis angulata (gooseberry), Physalis peruviana (cape gooseberry), Solanum americanum (American black nightshade), Solanum bonariense, Solanum elaeagnifolium (silverleaf nightshade), Solanum gracilius, Solanum hirtum, Solanum lycopersicum (tomato), Solanum muricatum (sweet cucumber), Solanum nigrum (black nightshade), Solanum melongena (eggplant), Solanum pseudo-capsicum (Jerusalem cherry), Solanum sisymbriifolium (sticky nightshade), Solanum tuberosum (potato)1.  Eggs are laid on all above ground parts of host plants1.  Young larvae mine leaves, stems, shoots, flowers, and developing fruit1.  Later instars may feed on mature fruit1.  Pupae can be found attached to all plant parts (leaves, stems, flowers, fruit) as well as in soil1Tuta absoluta can be transported long distances when infested plants, fruit, or reusable packing boxes are moved1.  Significant quantities of fresh host material from infested areas enters California by air through Los Angeles each year.  In 2008 570 tons of fresh tomatoes were flown into Los Angeles from the Netherlands as were 14 tons from Spain and 6 tons from Chile1.

Worldwide Distribution: Tuta absoluta is native to South America1.  Since 2008 it has invaded much of Europe, northern Africa, and the Middle East1.

Official Control: Tuta absoluta is also listed as a harmful organism by Canada, Guatemala, Honduras, Japan, Georgia and the Russian Federation3.  It is also under official control in Mexico4.

California Distribution:  Tuta absoluta has never been found in California.

California Interceptions:  Tuta absoluta has never been intercepted by CDFA.

The risk Tuta absoluta (tomato leafminer) would pose to California is evaluated below.

Consequences of Introduction: 

1) Climate/Host Interaction: Tuta absoluta is likely to establish throughout southern California, the central coast, and the San Joaquin valley. It receives a High (3) in this category.

Evaluate if the pest would have suitable hosts and climate to establish in California.  Score:

Low (1) Not likely to establish in California; or likely to establish in very limited areas.

Medium (2) may be able to establish in a larger but limited part of California.

High (3) likely to establish a widespread distribution in California.

2) Known Pest Host Range: Tuta absoluta is known to feed on 22 species of plants in one plant family.  It receives a Medium (2) in this category.

Evaluate the host range of the pest. Score:

Low (1) has a very limited host range.

Medium (2) has a moderate host range.

High (3) has a wide host range.

3) Pest Dispersal Potential: Tuta absoluta has high reproductive potential.  It can complete 7-12 generations per year with each female laying up to 260 eggs1.  The moth can rapidly spread long distances when infested plants, fruit, or packing containers are moved.  It receives a High (3) in this category.

Evaluate the natural and artificial dispersal potential of the pest. Score:

Low (1) does not have high reproductive or dispersal potential.

Medium (2) has either high reproductive or dispersal potential.

High (3) has both high reproduction and dispersal potential.

4) Economic Impact: Tuta absoluta reduces tomato yields by up to 100% and is considered one of the worst pests of processing tomatoes in Brazil1.  This moth has the potential to lower crop yields and increase production costs in California.  If Tuta absoluta were to establish in California it is also likely to disrupt markets for California fresh fruit and plants.  Tuta absoluta receives a High (3) in this category.

Evaluate the economic impact of the pest to California using the criteria below. Score:

A.  The pest could lower crop yield.

B.  The pest could lower crop value (includes increasing crop production costs).

C.  The pest could trigger the loss of markets (includes quarantines).

D.  The pest could negatively change normal cultural practices.

E.  The pest can vector, or is vectored, by another pestiferous organism.

F.  The organism is injurious or poisonous to agriculturally important animals.

G.  The organism can interfere with the delivery or supply of water for agricultural uses.

Low (1) causes 0 or 1 of these impacts.

Medium (2) causes 2 of these impacts.

High (3) causes 3 or more of these impacts.

5) Environmental Impact: If Tuta absoluta were to establish in California it is likely to trigger new treatment programs by growers and residents who find infested plants unacceptable.  Tomatoes are one of the most popular plants in home/urban gardens and are likely to be significantly affected by this pest.  Tuta absoluta receives a High (3) in this category.

Evaluate the environmental impact of the pest on California using the criteria below.

A.  The pest could have a significant environmental impact such as lowering biodiversity, disrupting natural communities, or changing ecosystem processes.

B.  The pest could directly affect threatened or endangered species.

C.  The pest could impact threatened or endangered species by disrupting critical habitats.

D.  The pest could trigger additional official or private treatment programs.

E.  The pest significantly impacts cultural practices, home/urban gardening or ornamental plantings.

Score the pest for Environmental Impact. Score:

Low (1) causes none of the above to occur.

Medium (2) causes one of the above to occur.

High (3) causes two or more of the above to occur.

Consequences of Introduction to California for Tuta absoluta (Tomato Leafminer):  High (14)

Add up the total score and include it here

Low = 5-8 points

Medium = 9-12 points

High = 13-15 points

6) Post Entry Distribution and Survey Information: Tuta absoluta has never been found in California and receives a Not established (0) in this category.

Evaluate the known distribution in California. Only official records identified by a taxonomic expert and supported by voucher specimens deposited in natural history collections should be considered. Pest incursions that have been eradicated, are under eradication, or have been delimited with no further detections should not be included.

Not established (0) Pest never detected in California, or known only from incursions.

Low (-1) Pest has a localized distribution in California, or is established in one suitable climate/host area (region).

Medium (-2) Pest is widespread in California but not fully established in the endangered area, or pest established in two contiguous suitable climate/host areas.

High (-3) Pest has fully established in the endangered area, or pest is reported in more than two contiguous or non-contiguous suitable climate/host areas.

Final Score:

The final score is the consequences of introduction score minus the post entry distribution and survey information score: High (14)

Uncertainty:

A closely related Gelechiid species, Keiferia lycopersicella (the tomato pinworm) occupies the ecological niche of the tomato leafminer in the United States1,2.  It is possible that existing treatments for tomato pinworm will preclude economic and ecological impacts of Tuta absoluta.  Alternatively, it is possible that if Tuta absoluta were to establish in California it could displace our native moth, causing unknown ecological effects.

Conclusion and Rating Justification:

Tuta absoluta meets the threshold to likely cause unacceptable consequences of introduction and it has an overall likelihood of introduction risk rating above negligible.  The moth is likely to have significant economic and environmental impacts if it were to establish in California.  An “A” rating is justified.

References:

1 Bloem, Stephanie and Esther Spaltenstein. 2011. New Pest Response Guidelines: Tomato Leafminer (Tuta absoluta).  United States Department of Agriculture Animal and Plant Health Inspection Service.  https://www.aphis.usda.gov/import_export/plants/manuals/emergency/downloads/Tuta-absoluta.pdf

2 Poe, S.L. 1999. Common name: tomato pinworm. Scientific name: Keiferia lycopersicella (Walshingham) (Insecta: Lepidoptera: Gelechiidae).  University of Florida Featured Creatures.  http://entnemdept.ufl.edu/creatures/veg/tomato/tomato_pinworm.htm

3 USDA Phytosanitary Certificate Issuance & Tracking System (PCIT) Phytosanitary Export Database (PExD).  https://pcit.aphis.usda.gov/pcit/

4 Dr. Julio Cesar Velázquez González. 2013. Operating instructions to implement the emergency device against Tuta absoluta (Lepidoptera: Gelichiidae) in Mexico.  Department of Plant Health Senasica.  https://translate.google.com/translate?hl=en&sl=es&u=http://senasica.gob.mx/includes/asp/download.asp%3FIdDocumento%3D25489%26IdUrl%3D60944%26down%3Dtrue&prev=search


Responsible Party:

Jason Leathers, 1220 N Street, Sacramento, CA, 95814, (916) 654-1211, plant.health[@]cdfa.ca.gov.


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Pest Rating:  A


Posted by ls