The fungus Phytophthora ramorum causes a serious plant disease which has the potential to attack a wide range of woody plants including rhododendron, viburnum and certain species of trees including beech. This disease has been found in many European countries including England, Wales and the Republic of Ireland, but has previously only been seen locally on imported plant material.
A Department spokesperson explained further: “This is the first time this disease has been found on an established site in Northern Ireland. It is important that the disease does not establish in Northern Ireland as it has the potential to cause significant damage to trees and landscapes. I would urge gardeners in the area to remain vigilant for symptoms of the disease. The Department will be providing information leaflets to nearby properties and further guidance is available on our web site.”
The Department has taken appropriate steps to contain this outbreak including requiring the destruction of the affected plant and the monitoring of a zone surrounding the site.
On rhododendron, the first indication of the disease is wilting of shoots. Affected shoots develop a brown to black colour that spreads along the twig and can move into the leaves where the leaf bases and tips blacken. Leaf infection can also occur without twigs being affected. Symptoms can be similar to those caused by related fungal diseases although development of this disease may be more rapid. Infection on viburnum often occurs at the stem base, causing wilting and death. There may also be brown/black leaf symptoms, especially on evergreen species and the flowers may be affected. On trees the disease can affect just the bark (as in beech) and/or leaves. Symptoms in beech are bleeding cankers on the bark.
The disease is favoured by damp conditions and the main means of spread is by rain splash.
NOTES TO EDITORS:
- P. ramorum is a potentially virulent pathogen which could cause significant damage to trees and landscapes if it were to become established. It poses a threat to certain tree species and other ecologically important plants. It is a non-indigenous pathogen in the UK and Ireland. During the past four years P. ramorum has only been detected on a very few occasions in Northern Ireland, and then on plants in trade. This is the first occasion that the pathogen has been found in a plant outside a nursery. In order to keep the UK and Ireland free of P. ramorum there is a stringent eradication programme in place. All infected plants are immediately destroyed to prevent the pathogen from spreading or becoming established.
- Phytophthora ramorum is a notifiable disease which is subject to statutory action to prevent its introduction and spread. If you suspect the presence of the disease on your premises you should contact the DARD helpline on 028 9052 4999 or www.dardni.gov.uk
- Further information on the disease is available on the internet at http://www.defra.gov.uk/planth/pestnote/newram.pdf
- All media enquiries to DARD Press Office, tel: 028 9052 4619. Out of office hours please contact the Duty Press Officer via pager number 076 9971 5440 and your call will be returned.
