Canada completes the re-evaluation of Agrobacterium radiobacter Strain K84

Under the authority of the Pest Control Products Act, all registered pesticides must be re-evaluated by Health Canada's Pest Management Regulatory Agency (PMRA) to ensure that they meet current health and environmental standards and have value. The re-evaluation considers data and information from pesticide manufacturers, published scientific reports and other regulatory agencies, as well as comments received during public consultations. Health Canada applies internationally accepted risk assessment methods as well as current risk management approaches and policies.

This document (the full version of Re-evaluation decision RVD2024-06, Agrobacterium radiobacter Strain K84 and its Associated End-use Product) presents the final re-evaluation decision for the re-evaluation of Agrobacterium radiobacter strain K84 including responses to comments received, and the required label updates. All products containing Agrobacterium radiobacter strain K84 regulated under the Pest Control Products Act in Canada are subject to this re-evaluation decision.

Agrobacterium radiobacter strain K84 is a naturally occurring soil-dwelling, gram-negative, short-rod aerobic bacterium used as a bactericide to control crown gall disease on seeds and nursery stock of stone fruit, pome fruit, berries, tree nuts, ornamental flowers, shrubs and trees as well as grapes and hops. The end-use product is applied to seeds, seedlings and cuttings (rootstock and rooted) at planting as a dip treatment only. The mode of action of Agrobacterium radiobacter strain K84 is through direct competition that is primarily facilitated by the production of a bacteriocin specific against certain pathogenic strains of Agrobacterium spp.

Currently registered end-use product containing Agrobacterium radiobacter strain K84 can be found in the Pesticide Product Information Database and in Appendix I. The Proposed Re-evaluation Decision PRVD2023-04, Agrobacterium radiobacter strain K84 and its Associated End-use Product containing the evaluation and proposed decision for Agrobacterium radiobacter strain K84, underwent a 90-day consultation period ending on 26 November 2023. PRVD2023-04 proposed continued registration of Agrobacterium radiobacter strain K84 and its associated registered end-use product for sale and use in Canada, with updates to label directions and precautions to reflect the current labelling standards and to improve clarity (Appendix IV of RVD2024-06).

Health Canada received comments during the public consultation. Commenters are listed in Appendix II of RVD2024-06. The comments are summarized in Appendix III of RVD2024-06 along with the responses by Health Canada. The comments did not result in revisions or changes to the proposed re-evaluation decision as described in PRVD2023-04. A reference list of information used as the basis for the proposed re-evaluation decision is included in PRVD2023-04.

Re-evaluation decision for Agrobacterium radiobacter strain K84

Health Canada has completed the re-evaluation of Agrobacterium radiobacter strain K84. Under the authority of the Pest Control Products Act, Health Canada has determined that continued registration of products containing Agrobacterium radiobacter strain K84 is acceptable. An evaluation of available scientific information found that the use of Agrobacterium radiobacter strain K84 products meets current standards for protection of human health and the environment and have acceptable value when used according to revised conditions of registration which includes label amendments.

Appendix I Registered product containing Agrobacterium radiobacter strain K84 in Canada