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. 2023 Jul 28;21(7):e08118. doi: 10.2903/j.efsa.2023.8118
Overview of the evaluation of Phytophthora kernoviae for bundles of whips and seedlings
Rating of the likelihood of pest freedom Pest free with some exceptional cases (based on the Median).
Percentile of the distribution 5% 25% Median 75% 95%
Proportion of pest‐free bundles 9,930 out of 10,000 bundles 9,962 out of 10,000 bundles 9,980 out of 10,000 bundles 9,992 out of 10,000 bundles 9,998.1 out of 10,000 bundles
Percentile of the distribution 5% 25% Median 75% 95%
Proportion of infected bundles 1.9 out of 10,000 bundles 8 out of 10,000 bundles 20 out of 10,000 bundles 38 out of 10,000 bundles 70 out of 10,000 bundles
Summary of the information used for the evaluation

Possibility that the pest could become associated with the commodity

Phytophthora kernoviae is present in the UK with a restricted distribution. The pathogen has a wide host range including Fagus sylvatica. The main host (e.g. Rhododendron spp.) can be present in the surroundings of the nurseries. Aerial inoculum could be produced on these host plants and cause bark infections on the commodity.

Measures taken against the pest and their efficacy

P. kernoviae is a provisional quarantine pest in the UK and under official control. General measures taken by the nurseries are effective against the pathogen. These measures include (a) the use of certified plant material and growing media; (b) inspections, surveillance, monitoring, sampling and laboratory testing; and (c) application of pest control products.

Interception records

In the EUROPHYT/TRACES‐NT database, there are no records of notification of F. sylvatica plants for planting neither from the UK nor from other countries due to the presence of P. kernoviae between the years 1995 and December 2022 (EUROPHYT, online; TRACES‐NT, online).

Shortcomings of current measures/procedures

None observed.

Main uncertainties
  • Whether symptoms may be promptly detected.
  • The presence/abundance of the pathogen in the area where the nurseries are located.
  • Effect of fungicide treatments against the pathogen.
Overview of the evaluation of Phytophthora kernoviae for bare root plants/trees up to 7 years old
Rating of the likelihood of pest freedom Pest free with some exceptional cases (based on the Median).
Percentile of the distribution 5% 25% Median 75% 95%
Proportion of pest‐free plants 9,944 out of 10,000 plants 9,972 out of 10,000 plants 9,986 out of 10,000 plants 9,994 out of 10,000 plants 9,998.5 out of 10,000 plants
Percentile of the distribution 5% 25% Median 75% 95%
Proportion of infected plants 1.5 out of 10,000 plants 6 out of 10,000 plants 14 out of 10,000 plants 28 out of 10,000 plants 56 out of 10,000 plants
Summary of the information used for the evaluation

Possibility that the pest could become associated with the commodity

Phytophthora kernoviae is present in the UK with a restricted distribution. The pathogen has a wide host range including Fagus sylvatica. The main host (e.g. Rhododendron spp.) can be present in the surroundings of the nurseries. Aerial inoculum could be produced on these host plants and cause bark infections on the commodity.

Measures taken against the pest and their efficacy

P. kernoviae is a provisional quarantine pest in the UK and under official control. General measures taken by the nurseries are effective against the pathogen. These measures include (a) the use of certified plant material and growing media; (b) inspections, surveillance, monitoring, sampling and laboratory testing; and (c) application of pest control products.

Interception records

In the EUROPHYT/TRACES‐NT database, there are no records of notification of F. sylvatica plants for planting neither from the UK nor from other countries due to the presence of P. kernoviae between the years 1995 and December 2022 (EUROPHYT, online; TRACES‐NT, online).

Shortcomings of current measures/procedures

None observed.

Main uncertainties
  • Whether symptoms may be promptly detected.
  • The practicability of inspections of older trees.
  • The presence/abundance of the pathogen in the areas where the nurseries are located.
  • Effect of fungicide treatments against the pathogen.
Overview of the evaluation of Phytophthora kernoviae for plants in pots up to 15 years old
Rating of the likelihood of pest freedom Pest free with some exceptional cases (based on the Median).
Percentile of the distribution 5% 25% Median 75% 95%
Proportion of pest‐free plants 9,922 out of 10,000 plants 9,962 out of 10,000 plants 9,980 out of 10,000 plants 9,991 out of 10,000 plants 9,997.9 out of 10,000 plants
Percentile of the distribution 5% 25% Median 75% 95%
Proportion of infected plants 2.1 out of 10,000 plants 9 out of 10,000 plants 20 out of 10,000 plants 38 out of 10,000 plants 78 out of 10,000 plants
Summary of the information used for the evaluation

Possibility that the pest could become associated with the commodity

Phytophthora kernoviae is present in the UK with a restricted distribution. The pathogen has a wide host range including Fagus sylvatica. The main host (e.g. Rhododendron spp.) can be present in the surroundings of the nurseries. Aerial inoculum could be produced on these host plants and cause bark infections on the commodity.

Measures taken against the pest and their efficacy

P. kernoviae is a provisional quarantine pest in the UK and under official control. General measures taken by the nurseries are effective against the pathogen. These measures include (a) the use of certified plant material and growing media; (b) inspections, surveillance, monitoring, sampling and laboratory testing; and (c) application of pest control products.

Interception records

In the EUROPHYT/TRACES‐NT database, there are no records of notification of F. sylvatica plants for planting neither from the UK nor from other countries due to the presence of P. kernoviae between the years 1995 and December 2022 (EUROPHYT, online; TRACES‐NT, online).

Shortcomings of current measures/procedures

None observed.

Main uncertainties
  • Whether symptoms may be promptly detected.
  • The practicability of inspections of older trees.
  • The presence/abundance of the pathogen in the area where the nurseries is located.
  • Effect of fungicide treatments against the pathogen.
  • Whether and to which extent plants transplanted to the pots before export have undergone a cleaning of roots.