Action Plan for Ralstonia solanacearum, Race 3 (Biovar 2)

October 3, 2007

Protocol for plant material potentially infected with Ralstonia solanacearum, Race 3 (Biovar 2)

CURRENT SITUATION: In the spring of 2003 the CFIA identified Ralstonia solanacearum, Race 3 (Biovar 2) for the first time in imported Pelargonium spp. (geranium) propagative material in Canada. Trace-outs, trace-backs and a survey of imported Pelargonium were carried out to identify additional greenhouses that may have been infected. A total of four Canadian greenhouses were confirmed as being infected and all implicated plant material was destroyed.

On June 20, 2003, policy directive D-03-09 (2003-09-11, 1st revision): Import Requirements for Pelargonium spp. and Solanum spp. Propagative Material to Prevent the Entry of Ralstonia solanacearum, Race 3 (Biovar 2) into Canada, came into effect. This interim policy is being implemented on an emergency basis as a precaution to prevent the introduction of Ralstonia solanacearum, Race 3 (Biovar2) into Canada.

BACKGROUND: This Action Plan describes the protocol to be used by the CFIA for greenhouses containing plant material potentially infected with Ralstonia solanacearum, Race 3 (Biovar 2). Please refer to Appendix 1 for a Fact Sheet on Bacterial Wilt of Geraniums, Ralstonia solanacearum, Race 3 (Biovar 2) (Synonym: Pseudomonas solanacearum).

DEFINITIONS:

Suspect Geraniums (Pelargonium spp.):
All plants within a facility that have been identified by inspection, testing, traceback or traceforward as potential primary sources of Ralstonia infection. This includes:

• All geraniums and cuttings from those plants that show wilt symptoms consistent with infection by Ralstonia solanacearum, Race 3 (Biovar 2) (See Appendix 1) and;
• Any plants that have been identified as being infected with Ralstonia spp. or with Ralstonia solanacearum, Race 3 (Biovar 2) and;
• All geraniums of the same variety and from the same shipment as geraniums that test positive for Ralstonia spp. or Ralstonia solanacearum, Race 3 (Biovar 2).

Suspect Plant Material:
All plants within a facility that are at a high risk of secondary infection by the Suspect Geraniums, if the Suspect Geraniums are found positive for Ralstonia solanacearum, Race 3 (Biovar 2). This includes:

• all cuttings and plants propagated from Suspect Geraniums;
• all mother plants of Suspect Geraniums;
• all cuttings and plants propagated from suspect mother plants;
• any geraniums that originate from the same shipment as the Suspect Geraniums that are at risk of Ralstonia infection or contamination;
• all plants, regardless of their host status and origin, that share a growing container with Suspect Geraniums.

Plant Material at Risk:
All other plant material within a facility that is at risk of Ralstonia infection or contamination from the Suspect Geraniums or Suspect Plant Material. This includes:

• all potential host plants (See Appendix 2) that have been within one-metre of Suspect Plant Material at any time;
• all plants that have been in contact with water from potentially contaminated irrigation systems;
• all plants exposed to contamination from irrigation water run off (such as plants under hanging baskets that contain Suspect Plant Material;
• all plants that are at risk of infection because of inadequate greenhouse sanitation procedures.

INVESTIGATION:

• Determine the origin of all Suspect Plant Material.
• Determine the history of movement of all Suspect Geraniums, Suspect Plant Material and all Plant Material at Risk.
• Determine the type of irrigation system used, any safeguards against water back flow in the irrigation system, and any water treatment practices in place. Determine the source of irrigation water and where drainage water leaving the facility goes.
• Document the greenhouse sanitation practices that are in place.
• Record the presence of other potential host material (Appendix 2) in the greenhouse and the location of any cull piles that may be contaminated with Suspect Plant Material, or associated soil.
• All potential host plants of Ralstonia solanacearum Race 3 (Biovar2) must be visually inspected in each greenhouse at the production facility at least twice a week (Appendix 2). All plants exhibiting symptoms consistent with Ralstonia infection must be sampled (Appendix 6). Symptoms and reference photos can be found in CFIA's Ralstonia Fact Sheet (Appendix 1).

REGULATORY ACTION:

• Suspect Geraniums, Suspect Plant Material, Plant Material at Risk and all associated growing media must be controlled under Notices of Quarantine.
• Quarantine Notices should include required treatments, such as basic sanitary measures, as conditions.
• The facility must put Basic Sanitary Procedures in place, as described in Appendix 3, to prevent potential contamination of other greenhouses and plant material.

CONDITIONS FOR RELEASE:

Quarantined plants may be released from regulatory action by written CFIA order after one or more of the following can be demonstrated:

• voluntary destruction of Suspect Geraniums, Suspect Plants and /or Plant Material at Risk under the supervision of the CFIA according to approved procedures (Appendix 4 and Appendix 5);
• symptomatic host plants (see Appendix 6) are sampled and submitted for testing (as described in Appendix 6) and found free of Ralstonia solanacearum Race 3 (Biovar 2) and the holding period of three weeks has been completed;
• all positive detections are handled in accordance with the Section "Positive CFIA Test Results", described below, and traceback and traceforward investigations indicate that the facility is not at risk of disseminating Ralstonia solanacearum Race 3 (Biovar 2).

POSITIVE CFIA TEST RESULTS

If plants within a facility test positive for Ralstonia solanacearum Race 3 (Biovar 2) the following additional regulatory actions must be taken:

• Infected Suspect Geraniums and all Suspect Plant Material associated with the infected plants within a greenhouse that are identified as being infected with Ralstonia solanacearum Race 3 (Biovar 2) must be destroyed according to the destruction protocol described in Appendix 4.
• All remaining Suspect Plant Material and Plant Material at Risk present in the greenhouse will remain under quarantine. CFIA will monitor all remaining host material in the greenhouse. (See list of host plants in Appendix 2.) The monitoring will involve visual inspection of all potential host material remaining in the greenhouse for three weeks. Symptomatic plants will be sampled by variety and sent to the designated CFIA laboratory for testing (Appendix 6). Additional testing for latent infections may be done at the discretion of the CFIA. Any confirmation of the presence of Ralstonia solanacearum Race 3 (Biovar 2) in the greenhouse will initiate further regulatory actions.
• The greenhouse must complete the Post - Destruction Sanitary Measures described in Appendix 5 after the plant material that has been ordered destroyed has been removed from the greenhouse. In addition, soil floors and any water drainage systems that could potentially be infected with Ralstonia must be treated in a manner approved by the CFIA.
• Ensure that all facilities that may have received infected plant material have been identified.

LIST OF APPENDICES
Appendix 1: Bacterial Wilt of Geraniums
Appendix 2: Host Plants of Ralstonia solanacearum, Race 3 (Biovar 2)
Appendix 3: Basic Sanitation Procedures for Greenhouses
Appendix 4: Destruction Protocol
Appendix 5: Post-Destruction Sanitary Measures
Appendix 6: Greenhouse Inspection and Sampling of Pelargonium for Ralstonia solanacearum, Race (Biovar 2)

Appendix 1

Bacterial Wilt of Geraniums

Appendix 2

Host Plants of Ralstonia solanacearum Race 3 (Biovar 2)

The following genera contain species that are considered to be potential host plants of Ralstonia solanacearum Race 3 (Biovar2): The names of known natural hosts are in bold face.

Appendix 3

Basic Sanitation Procedures for Greenhouses

The following basic sanitary measures must be implemented immediately in all facilities containing Suspect Geraniums:

• Regular disinfection of all hand tools and implements (i.e. knives, pruners, water breakers and water wands) during and after use.
• Ensure a disinfectant foot bath is placed at the entrance to each greenhouse containing suspect material. The foot bath must be maintained and filled with fresh disinfectant daily.
• Everyone entering and leaving the facility must walk through the disinfectant foot bath and those working with, or in contact with suspect plants, must wash hands using soap, or disinfectant immediately after.
• Workers must wear clothing that is newly laundered each day.
• Restrict visitors to the facility. Do not visit other commercial greenhouses operations in potentially contaminated work clothing and footwear.
• Destroy weeds in and around the greenhouse, particularly those that are potential hosts of Ralstonia. Please refer to the list of potential host plants in Appendix 2.

^* Effective disinfectants include products such as: quaternary ammonia compounds, peroxygen compounds, and bleach. Disinfectants must be used according to label rates and instructions. Please refer to provincial production guides and recommendations for detailed instructions.

Appendix 4

Destruction Protocol

Material described under a Notice to Dispose will be destroyed and disposed of under CFIA supervision. The greenhouse must be disinfected according to the Sanitation Instructions described in Appendix 5 before any new plant material can be placed in that location.

• All plants to be destroyed, associated growing media and associated growing containers (i.e. pots and trays) must be placed in double plastic bags of 4 mm thickness or greater. Any weed hosts of Ralstonia in the greenhouse, culled plant material, prunings and spilled soil from suspect plants must also be double bagged.
• Minimize any contact between plants that are to be destroyed and any other plant material, pots, and growing media. Make every effort to prevent debris or soil from dislodging or falling from suspect plants in order to prevent contamination of the greenhouse structure and the development of new infections. Avoid unnecessary movement of material destined for destruction.
• Material for destruction must be disposed of by incineration at a CFIA approved site, or deep burial at a CFIA approved municipal landfill, or by another method approved in writing by the CFIA.The Bagged material that is to be destroyed by deep burial, must be covered with a minimum of two feet of packed soil.
• After all plant material, growing media, growing containers, debris and spilled growing media that is destined for destruction has been removed from the greenhouse, clean and disinfect the growing area according to the Post-Destruction Sanitary Measures described in Appendix 5.

Appendix 5

Post-Destruction Sanitary Measures

Once all plant material and associated growing media and growing containers destined for destruction have been removed from the greenhouse:

• Clean and disinfect the growing areas where the destroyed material was, including: benches, concrete walkways and floors by washing with a mild detergent and then applying a disinfectant.
• Disinfect all tools using products listed above.
• Irrigation systems that could potentially be infected with Ralstonia must be drained and circulated with disinfection solutions approved by provincial authorities. This could include the hoses and nozzles of hand watering systems, recirculating irrigation systems, sub-irrigation systems and those irrigation systems that have no backflow prevention devices.
• Potting equipment and any other equipment that may have been in contact with plant material destined for destruction must be cleaned and disinfected.

^* Effective disinfectants include products such as: quaternary ammonia compounds, peroxygen compounds, and bleach. Disinfectants must be used according to label rates and instructions. Please refer to provincial production guides and recommendations for detailed instructions.

Appendix 6

Greenhouse Inspection and Sampling of Pelargonium for Ralstonia solanacearum, Race 3(Biovar 2)

1.0 Inspection Method

All potential host plants of Ralstonia solanacearum Race 3 (Biovar2) must be visually inspected in each greenhouse at the production facility (Appendix 2). All plants exhibiting symptoms consistent with Ralstonia infection must be sampled. Symptoms and reference photos can be found in CFIA's Ralstonia Fact Sheet (Appendix 1).

2.0 Sample Collection and Handling

The inspector must wear a new pair of disposable gloves and booties and use a new plastic knife at each facility sampled. After sampling a greenhouse discard all the knives, gloves and booties used in that greenhouse.

Since the pathogen is concentrated in the lower parts of the plant, testing must be done on a 1-2 cm segment taken from the base of the main stem just above the soil level. Samples must be handled and in a manner that ensures that the samples are not contaminated by soil.

Samples may include the basal portion of the main stem, or the entire plant. If the entire plant is sampled, the pot or the rootball should be bagged and secured around the stem and then the entire plant should be placed inside a second bag to prevent the soil from contaminating the sample. Otherwise, use a plastic serrated knife to cut a 3 cm segment from the main stem of the plant from the soil line upward. Place stem samples into sealable plastic bags with a maximum of 20 stems per bag and the varieties separated.

Label each bag using a permanent marker with the greenhouse name, plant variety, date and sample identification number.

3.0 Lab Submissions

Samples must be handled and transported in a manner that ensures that they arrive at the laboratory in good condition and that the samples are not contaminated by soil.

• Store plant samples in a cold room or refrigerator at 4°C ± 2°C prior to shipping (do not allow samples to freeze).
• Ship in a Styrofoam cooler without an ice pack.
• Complete one Pest Identification Report (CFIA/ACIA 1303) per greenhouse per sampling day and submit a copy with the samples. Include: the greenhouse name and address and the number of samples included in the submission by variety.
• Write "Ralstonia" on outside of the box and send by express messenger or 24 hour service courrier to:
  
  CFIA, Ottawa Laboratory (Fallowfield)
  3851 Fallowfield Rd
  Ottawa, Ontario K2H 8P9
  Telephone: 613-228-6698
  Facsimile: 613-228-6676