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RMD-10-26: Tuta absoluta (tomato leaf miner moth; South American tomato moth)

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Issued: 2011-02-03


As described by the International Plant Protection Convention (IPPC), Pest Risk Analysis (PRA) includes three stages: initiation, pest risk assessment and pest risk management. Initiating the PRA process involves identifying pests and pathways of concern and defining the PRA area. Pest risk assessment provides the scientific basis for the overall management of risk. Pest risk management is the process of identifying and evaluating potential mitigation measures which may be applied to reduce the identified pest risk to acceptable levels and selecting appropriate measures.

This Risk Management Document (RMD) includes a summary of the findings of a pest risk assessment and records the pest risk management process for the identified issue. It is consistent with the principles, terminology and guidelines provided in the IPPC standards for pest risk analysis.

Table of Contents

Executive Summary

Tuta absoluta is an emerging pest of tomatoes (Solanum lycopersicum) for Canada. It is recognized around the world as a serious pest of tomato production. This insect originates in South America but, in the past few years it has spread rapidly through countries in the Mediterranean Basin and has more recently become established in greenhouse environments in Northern Europe. Tuta absoluta is very damaging to tomato plants and damage on tomato fruit makes it unmarketable. There does not appear to be a successful method of eliminating a T. absoluta infestation from a greenhouse using conventional pest control measures. Although T. absoluta is a tropical pest and not expected to survive year round in Canada, it is very likely that if a Canadian greenhouse were to become infested, that T. absoluta would successfully spread to surrounding greenhouse operations during the summer months.

Tuta absoluta is a quarantine pest to the United States (U.S.) and the United States Department of Agriculture (USDA) has phytosanitary import requirements in place to mitigate the risk of introducing this pest to the U.S. with tomato fruit from infested countries. As of February 1, 2010 Solanum spp., Nicotiana spp. and Datura spp. plants, which are known hosts of T. absoluta, will also be prohibited from entering the U.S. from affected countries, pending the completion of a Pest Risk Analysis (PRA).

Canada exports a large volume of fresh, greenhouse-grown tomatoes to the U.S. In addition, Canada exports high value tomato plantlets to the U.S. for greenhouse tomato production. Canadian produced tomatoes and tomato plants are not impacted by the USDA's Federal Order. However, tomato fruit that enters Canada from countries regulated by the U.S. may not be re-exported to the U.S. Canada has prohibited the entry of Solanum spp. and Nicotiana spp. plants for planting from all countries except the U.S. for decades. At present, Canada has no phytosanitary requirements for imported tomato fruit.

A Pest Risk Assessment to evaluate the plant health risk associated with T. absoluta was completed in May 2009. According to the PRA, the probability of entry, establishment and spread of T. absoluta in the indoor environment (i.e. greenhouses) in Canada is considered to be medium to high. If T. absoluta were to be introduced to Canada, the impact on the Canadian greenhouse industry is expected to be severe, both in terms of direct pest damage and in maintaining access to U.S. markets.

The CFIA has prepared this Risk Management Document (RMD) to record the decision to put interim emergency measures in place to immediately mitigate the risk of introducing this pest to Canada until longer term requirements can be developed, consulted upon and implemented.

As of February 2010, shipments of tomato fruit from infested countries will be required to be accompanied by a Phytosanitary Certificate verifying freedom from T. absoluta. It is important that these phytosanitary import requirements be enforced immediately to mitigate the risk of this pest becoming established in Canada, and to reduce the risk of restrictions on Canada's exports of solanaceous crops to the U.S.

1.0 Purpose

The purpose of this document is:

2.0 Scope

This RMD describes the risks associated with the introduction of the South American tomato moth, Tuta absoluta, into Canada, and outlines the new requirements for hosts of T. absoluta.

Information pertaining to current import requirements for specific plants or plant products may be obtained from the Canadian Food Inspection Agency (CFIA) Automated Import Reference System

3.0 Definitions

Definitions for terms used in this document can be found in the Plant Health Glossary of Terms or the IPPC Glossary of Phytosanitary Terms.

4.0 Background

The CFIA Pest Risk Assessment for T. absoluta was completed in May 2009. It indicates that T. absoluta is a serious pest of tomatoes, but that it would not survive winters in Canada. It is therefore unlikely to spread without human assistance among greenhouse operations during cold weather. However, in warmer months greenhouses located in proximity to infested facilities or in areas where T. absoluta occurs in the outside environment may be at risk of infestation.

The number of countries reporting the presence of T. absoluta continues to increase and this insect has recently become established in greenhouse operations in Northern Europe. The United States (U.S.) has been evaluating the potential phytosanitary impact of T. absoluta and published Federal Orders on February 23 and May 12, 2009 regulating tomatoes from countries where T. absoluta is known to occur. Shipments of field-grown green tomatoes from Algeria, France, Italy, Morocco and Spain now must meet additional import requirements to prevent the introduction of T. absoluta. The U.S. has recently revised the Federal Order to update the list of countries infested with T. absoluta, adding Albania, Greece, the Netherlands, Portugal, Switzerland and Tunisia as regulated countries. Previous U.S. regulation already imposes requirements for the importation of pink and red tomatoes from these countries to prevent the introduction of the Mediterranean fruit fly, Ceratitis capitata. The new Federal Order, which came into effect on February 1, 2010, will also prohibit Solanum spp., Nicotiana spp. and Datura spp. plants for planting from affected countries pending the completion of a PRA. The U.S. imports a large volume of fresh tomatoes as well as tomato plantlets from Canada. In the course of revising their regulations, the United States Department of Agriculture (USDA) has inquired if the CFIA was considering taking any regulatory action with respect to this pest.

5.0 Pest Risk Assessment Summary

A Pest Risk Assessment (PRA 2009-19) to evaluate the potential risks related to the introduction of T. absoluta to Canada was completed in May 2009. The following sections present the highlights of the assessment.

5.1 Pest Biology

5.1.1 Life History

Tuta absoluta has a high reproductive potential. The female lays up to 260 eggs, mostly singly, on leaves, stems and young fruit. The larvae bore into the plant and, when older (3rd - 4th instar), leave their mines and travel to new locations to mine again. Pupation occurs in the mine, outside the mine and in the soil, as well as beneath pots and under benches. The insect requires warmth to survive and complete its development and therefore is only likely to survive out-of-doors in the summer in Canada. Up to 9 generations per year can occur in greenhouses.

5.1.2 Host Range

The major host of T. absoluta is Solanum lycopersicum (tomato). The insect can bore into all above-ground parts, including fruit. Other potential hosts include S. melongena (eggplant), S. tuberosum (potato), Nicotiana tabacum (tobacco) and Capsicum annuum (peppers). Datura stramonium and D. ferox have been reported to be wild hosts.

5.1.3 Symptoms

The moth attacks the leaf mesophyll, leaving the epidermis intact. The leaves may become necrotic and the growth of the plant can be altered as the growing tips die. Fruit, apical growing points and leaves show puncture marks where the larva has entered the plant surface. Early instar larvae usually attack the leaves, but can be found in growing points and in the flower, while later stage larvae, and especially when the populations are high, tend to attack the fruit. Infected fruit show puncture marks, exit holes and an abnormal shape. Mature fruit may show surface scarring.

5.2 Distribution

The insect is native to South America, from Ecuador to Northern Chile, west of the Andes, and to 1000 m elevation. In South America, it is known to occur in Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Paraguay, Peru, Uruguay and Venezuela. It is now reported in several countries in Europe including Albania, France, Greece, Italy, Malta, Portugal, the Netherlands, Spain, Switzerland and United Kingdom. In Northern Africa, it is now known to occur in Algeria, Libya, Morocco and Tunisia. In Asia, it is now present in Bahrain and Kuwait. It is likely to spread within Europe to occupy the entire Mediterranean Basin. Recently, it was reported to be present in greenhouses in the Netherlands and the United Kingdom, and to be spreading within the greenhouse industry. T. absoluta is capable of establishing in indoor environments even in climates where it would not survive outdoors.

5.3 Pathways

Tuta absoluta could be introduced to Canada by the importation of infested tomato fruit, tomato plants, and used tomato crates/packing boxes, although CFIA already prohibits tomato plants from all countries other than the continental U.S. The potential for transportation with other solanaceous crops or flowers is unknown, but is likely to be significantly lower than with tomatoes. The USDA considers Nicotiana spp. and Datura spp. plants to also be high risk pathways.

5.3.1 Entry Potential Fresh Tomatoes for Consumption

Fresh tomatoes are considered a high risk pathway for T. absoluta. The probability of this pest being associated with this pathway at origin as larvae or eggs is high for South America and probably also high for infested European, Asian and African countries. However, nearly 97% of Canada's imported tomatoes came from the U.S. ($149 million) and Mexico ($134 million) in 2008, neither of which has reported this pest. Other countries that ship tomatoes to Canada, and are infested with T. absoluta, include the Netherlands ($3 million), Spain ($3 million), Morocco ($350,000) and Italy ($200,000). These countries represented 1.12, 1.07, 0.12 and 0.07% of the value of tomatoes imported to Canada, respectively, in 2008.

Several Canadian production facilities also repack and/or distribute imported tomato fruit. This is a high risk activity if the imported fruit comes from infested countries and is a likely pathway for the introduction of this pest into Canadian greenhouses. Outdoor markets that sell tomatoes from infested countries and are located in areas with suitable summer conditions for survival of T. absoluta, also pose a risk.

The probability of larvae associated with fresh tomatoes surviving transport is high. In addition, the USDA has observed that fruit infested with early instar larvae are not readily separated from non-infested fruit during processing and packaging operations, and are not likely to be detected during inspections. Movement of the moth from Spain to the Netherlands, Switzerland and Russia via this pathway has been documented. However, the risk rating for Canada is regarded as medium because only 3% of the tomatoes imported to Canada currently come from infested countries. Tomato Plants for Planting

Currently, Canada's regulations only allow the importation of Solanum lycopersicum plants for planting from the U.S. The importation of all Solanum spp. plants for planting is prohibited from all other countries as per the Quarantine Circular 1C (77-04-19). As the moth is not known to occur in the U.S., the risk of this pathway is rated as negligible. Nicotiana spp. plants for planting are also prohibited entry to Canada from any country as per Memorandum 80-05-20. Datura spp. plants are currently not prohibited entry to Canada and permits to import this plant from several countries have been issued. Therefore, there is potential for entry of T. absoluta from infested countries via this pathway. The volume of imported Datura spp. plants is not known.

5.3.2 Establishment Potential

Tuta absoluta could establish in indoor environments in Canada, including greenhouses and indoor plantscapes. Canada does not have a suitable outdoor climate for permanent establishment of this pest because of its inability to survive our winter conditions. However, if it becomes established indoors, during the warmer weather this insect could migrate from greenhouses and temporarily establish outdoors.

Due to its biology and rapid development of pesticide resistance, very limited pest management strategies are available to control T. absoluta. Experience in other parts of the world indicates that currently applied outdoor and indoor pest control programs, including the use of pesticides, are not able to prevent its establishment. It is therefore unlikely that currently applied Canadian pest control measures and practices would effectively mitigate the ability of this pest to establish in Canada, either outdoors or indoors. If it were to establish indoors, crop destruction and greenhouse sanitation would be required if eradication is desired. Outdoor populations are not expected to survive through the winter. The risk rating is therefore high indoors, and negligible outdoors.

5.3.3 Spread Potential

The risk of spread is rated as medium since there is the potential that T. absoluta could spread and infest greenhouses in close proximity to infested outdoor fields or other infested greenhouses during warm weather. The moth flies and disperses well. However, there is some uncertainty surrounding the pest's ability to leave infested source areas and the speed at which a population could spread. Management practices that could restrict the entry of T. absoluta into greenhouses, such as screening vents and other openings, are not commonly in use by the Canadian greenhouse industry.

Recently, T. absoluta moths have been observed to be moving in crates and packing material from packinghouses to growers in the U.K. The rapid spread of T. absoluta across Mediterranean Spain to France and into North Africa, i.e. in 2 years, suggests that it has been frequently overlooked and inadvertently carried to new areas, where it easily finds new hosts. Many production greenhouses in Canada also repackage and distribute tomato fruit produced at other Canadian greenhouses. This presents a potential a pathway for spread of this pest within Canada.

5.4 Potential Economic and Environmental Consequences

The potential economic and environmental risk associated with T. absoluta is rated as high. If it becomes established in a greenhouse, the costs of control will be substantial. The only currently known effective eradication method is complete crop destruction and greenhouse sanitation. This would need to be followed by surveys to delimit the extent of the incursion in neighbouring greenhouses and, in warm weather, in surrounding fields. The most significant indirect effect of establishment of a transient population in Canada would be a rapid and strong response from the U.S. and Mexico impacting Canada's trade with these countries.

6.0 Risk Management Considerations

Greenhouse tomatoes are an important industry to Canada. In 2008, 464 ha of tomatoes were grown in greenhouses for a total farm value of over $371 million (Statistics Canada, 2008). That same year, Canadian greenhouse producers exported $283.4 million worth of tomatoes, of which 99.8% were sold to the U.S. (Agriculture and Agri-Food Canada [AAFC], 2008). Canadian producers also exported $2.7 million worth of field tomatoes to the U.S. in 2008.

The introduction of T. absoluta would have a significant impact on greenhouse facilities. Crop management in tomato greenhouses relies mainly on the use of biological control agents. Use of pesticides is often restricted to specific situations where biological control agents are ineffective at controlling a pest. Limited use of pesticides is necessary for the survival of biological control agents, and of bumblebees introduced in greenhouses for pollination. Moreover, very limited pest management strategies are available to eradicate this insect. If introduced in a greenhouse, growers would have to destroy their crop and undertake greenhouse sanitation. It is important to note that some growers do not usually perform greenhouse sanitation between crops and plant their new crop below the old, production crop so that harvest continues almost all year round. There are currently no records indicating that T. absoluta has ever been successfully eradicated from a greenhouse. As tomatoes are a high-value crop, any greenhouse tomato facilities detecting T. absoluta would be subjected to significant monetary losses.

Since the first detection in Spain in 2006, T. absoluta has rapidly spread across Southern Europe and North Africa. Considering the quick spread of T. absoluta in Europe, it would be prudent to consider all European tomatoes to be potentially infested. The insect is reported to have successfully established in greenhouses in Malta, Portugal, Greece and Albania. Recently, it has been found in greenhouses in areas where it could not establish outdoors, i.e. the Netherlands and the United Kingdom. As of July 2009, several findings of the moth in the Netherlands (56 times, 256 moths at 13 companies) and the United Kingdom (58 times, 18 companies) were associated with infested tomatoes imported from Spain and Italy, that were shipped to packing stations (Potting, 2009). In the Netherlands, a survey was carried out in greenhouses close to packing stations, which resulted in captures in 24 out of 85 greenhouses. Tomato fruit is clearly an important pathway for spreading this pest from infested areas, and may be followed by rapid spread into neighbouring greenhouses during the summer.

7.0 Risk Management Decision

The CFIA has decided to put interim emergency measures in place to reduce the risk of entry of T. absoluta into Canada. It is important that these phytosanitary import requirements be implemented immediately in order to effectively mitigate the risk of this pest becoming established in Canada and to avoid the subsequent risk of any quarantine action on Canada's exports of solanaceous crops to the U.S. The risk of introduction is the highest during the winter months when Canada imports most tomato fruit.

In February 2010, CFIA will put measures in place to ensure that tomato fruit entering Canada from countries where T. absoluta is known to occur is accompanied by a Phytosanitary Certificate with an additional declaration stating:

"This consignment originated from a place where Tuta absoluta is known not to occur and was inspected and found free of Tuta absoluta".

Following the implementation of interim emergency measures, longer term requirements will be developed. The CFIA will consult with stakeholders to determine appropriate risk management options.

The CFIA will continue to prohibit Solanum spp. and Nicotiana spp. plants for planting and will not issue any additional permits to import Datura spp. from infested countries until a PRA on this plant as a pathway for quarantine pests is completed. Active Permits to Import will be cancelled or amended to prohibit further importation of plants for planting of Datura spp.

The implementation of this option will mitigate the medium potential risk of introduction, the high potential risk of establishment and the high potential economic consequences of T. absoluta in indoor environments in Canada. The risk of quarantine action by our trading partners, in particular the U.S., will also be minimized. The cost of taking this interim action on T. absoluta will be low compared to the potential economic losses arising from detection of T. absoluta in Canada since it will avoid the need for Canadian tomato producers to control, eradicate and manage this pest, and will maintain market access to the U.S. and potentially other countries.

Following the implementation of these interim requirements, shipments of tomato fruit will be referred to the CFIA Import Service Centres (ISCs) by the Canadian Border Services Agency (CBSA). The ISCs will review the paperwork. CFIA staff will inspect a representative sample of incoming shipments of tomato fruit from infested countries to verify compliance, and importers will be charged the appropriate fees specified by the Canadian Food Inspection Agency Fees Notice. Upon regulation, Canada will be obligated to control or eradicate T. absoluta if detected in Canada.

The phytosanitary requirements for tomato fruit will be made available in a policy directive currently under development.

8.0 Stakeholder Communications

The following trading partners and stakeholders will be notified of changes in import requirements resulting from the risk management decision:

In addition, the CFIA intends to work in partnership with provincial agricultural ministries and industry stakeholders to identify best management practices to mitigate the risk of introducing this pest into Canadian greenhouses and to prepare strategies for eradicating this pest should it be detected.

9.0 References

Agriculture and Agri-Food Canada. 2008. Canada's Tomato Industry Report.

Canadian Food Inspection Agency. Plant Protection Import Requirements for Plants and Plant Parts for Planting: Preventing the Entry and Spread of Regulated Plant Pests Associated with the Plants for Planting Pathway (D-08-04).

Damus, M. 2009. Pest Risk Assessment Request No. 2009-19, Tuta absoluta, South American tomato moth. Plant Health Risk Assessment Unit, Canadian Food Inspection Agency.

International Plant Protection Convention. International Standards for Phytosanitary Measures (ISPM) No. 4: Requirements for the establishment of Pest Free Areas, 1995 (2005 edition), Rome, FAO.

Potting, R. 2009. Pest Risk Analysis: Tuta absoluta, Tomato leaf miner moth or South American tomato moth. Plant Protection Service of the Netherlands, Ministry of Agriculture, Nature and Food Quality.

Statistics Canada. 2008. Greenhouse, Sod and Nursery Industries. Statistic Canada catalogue no. 22-202-X, p. 11. (accessed October 2009)

Plant Products and Quarantine Division (Agriculture Canada). Memorandum 80-05-20

Plant Quarantine Division (Agriculture Canada). Quarantine Circular 1C (77-04-19)

10.0 Endorsement

Approved by:

Chief Plant Health Officer

Date modified: