NAME OF THE ORGANISM: Phytophthora (1PHYTG)
GENERAL INFORMATION ON THE PEST
Name as submitted in the project specification (if different to the preferred name):
Phytophthora spp.
Pest category:
Chromista
1- Identity of the pest/Level of taxonomic listing:
Is the organism clearly a single taxonomic entity and can it be adequately distinguished from other entities of the same rank?
Yes
Is the pest defined at the species level or lower?:
No
Can listing of the pest at a taxonomic level higher than species be supported by scientific reasons or can species be identified within the taxonomic rank which are the (main) pests of concern?
- No: Vegetable propagating and planting material (other than seeds) sector
Is it justified that the pest is listed at a taxonomic rank below species level?
Not relevant
Conclusion:
- Not candidate: Vegetable propagating and planting material (other than seeds) sector
Justification (if necessary):
When replying to the RNQP Questionnaire, for the Vegetable reproductive and planting material (excluding seeds) Sector, no EU Member State identified this entry as important and justified to keep Phytophthora listed at a higher level than the species level. No EU Member State proposed to replace this entry by pests listed at the Species level.
For the Ornamental sector, DE justified a listing of Phytophthora on Euphorbia pulcherrima considering that 'Several species of pests are important and cause similar damage and have an unacceptable economic impact. Listing at this level allows decision on visual inspection instead on sampling and testing/identification'. FR also identified this entry as important.
There are a number of Phytophthora species on Begonia x hiemalis (e.g. P. niederhauseri, P. cryptogea). Phytophthora spp. causes the main diseases of citrus. The most important are Phytophthora nicotiana var. parasitica and Phytophthora citrophthora causing a foot rot and gummosis on the main roots, root collar stem base and fruits. Crown rot and collar rot of apple are caused by several Phytophthora species, of which P. cactorum and P. syringae are the most important. The pathogens may also infect pear, but rarely cause problems in this crop. There are also a number of Phytophthora species on Euphorbia pulcherrima (e.g. P. nicotianae, P. cryptogea, P. nicotianae).
In the last twenty years climatic changes, like flooding or temperature increase, favour the spread and the settlement of the Phytophthora species. All species are plant pathogens that attack various parts of the plant including roots, crowns, stems, buds, flowers, fruits and leaves. Phytophthora species have an high evolutionary potential for environment adaptability: among others it is becoming increasingly evident that natural interspecific hybridization is a casual event in heterothallic Phytophthora evolution which could lead to an increase of virulence. Ornamentals in nurseries represent a high risk for the spread of Phytophthora potentially resulting in outbreaks of root diseases in home gardens, orchards, wild flower farms and natural ecosystems. P. cactorum, P. cinnamomi, P. cryptogea, P. drechsleri, P. nicotianae, P. palmivora, P. citrophthora, and P. citricola are the major species that causes severe damage in nurseries and can attack a wide range of plant species (> 3500). Moreover, for the generic detection and identification of these oomicetes different molecular techniques are available. Hystorically ITS region have been used but more recently methods based on the ras/related protein Ypt1 gene have been set up (Schena et al., 2006: Schena et al. 2008). In particular Schena et al. 2008 have developed a ‘molecular tool box’ for the identification of a number of Phytophthora species; the method is specific for the genus and sensitive enough to detect target species in infected leaves and infested soil and water samples. Experts concluded that Phytophthora are difficult to distinguish visually in the field/glasshouse and therefore it would seem practical to include the whole genera Phytophthora spp.
For the Ornamental sector, DE justified a listing of Phytophthora on Euphorbia pulcherrima considering that 'Several species of pests are important and cause similar damage and have an unacceptable economic impact. Listing at this level allows decision on visual inspection instead on sampling and testing/identification'. FR also identified this entry as important.
There are a number of Phytophthora species on Begonia x hiemalis (e.g. P. niederhauseri, P. cryptogea). Phytophthora spp. causes the main diseases of citrus. The most important are Phytophthora nicotiana var. parasitica and Phytophthora citrophthora causing a foot rot and gummosis on the main roots, root collar stem base and fruits. Crown rot and collar rot of apple are caused by several Phytophthora species, of which P. cactorum and P. syringae are the most important. The pathogens may also infect pear, but rarely cause problems in this crop. There are also a number of Phytophthora species on Euphorbia pulcherrima (e.g. P. nicotianae, P. cryptogea, P. nicotianae).
In the last twenty years climatic changes, like flooding or temperature increase, favour the spread and the settlement of the Phytophthora species. All species are plant pathogens that attack various parts of the plant including roots, crowns, stems, buds, flowers, fruits and leaves. Phytophthora species have an high evolutionary potential for environment adaptability: among others it is becoming increasingly evident that natural interspecific hybridization is a casual event in heterothallic Phytophthora evolution which could lead to an increase of virulence. Ornamentals in nurseries represent a high risk for the spread of Phytophthora potentially resulting in outbreaks of root diseases in home gardens, orchards, wild flower farms and natural ecosystems. P. cactorum, P. cinnamomi, P. cryptogea, P. drechsleri, P. nicotianae, P. palmivora, P. citrophthora, and P. citricola are the major species that causes severe damage in nurseries and can attack a wide range of plant species (> 3500). Moreover, for the generic detection and identification of these oomicetes different molecular techniques are available. Hystorically ITS region have been used but more recently methods based on the ras/related protein Ypt1 gene have been set up (Schena et al., 2006: Schena et al. 2008). In particular Schena et al. 2008 have developed a ‘molecular tool box’ for the identification of a number of Phytophthora species; the method is specific for the genus and sensitive enough to detect target species in infected leaves and infested soil and water samples. Experts concluded that Phytophthora are difficult to distinguish visually in the field/glasshouse and therefore it would seem practical to include the whole genera Phytophthora spp.
HOST PLANT N°1: Cucumis sativus (CUMSA) for the Vegetable propagating and planting material (other than seeds) sector.
Origin of the listing:
2 - Vegetable seedling sector: Commission Directive 93/61/EC
Plants for planting:
Plants intended for planting
CONCLUSION ON THE STATUS:
Disqualified: No EU Member State considered this entry as important in the answers to the RNQP Questionnaire and gave justification(s) for a listing at a higher level than the species level. This entry will be covered by the 'Substantially free from' requirement that will remain in the Vegetable propagating and planting (excluding seeds) EU Marketing Directives.
8 - Tolerance level:
Is there a need to change the Tolerance level:
No
Proposed Tolerance levels:
Delisting.
9 - Risk management measures:
Is there a need to change the Risk management measure:
No
Proposed Risk management measure:
Delisting.
REFERENCES: