News from the Diagnostic Centre of the Dutch Plant Protection Service
The Diagnostic Centre of the Plant Protection Service of the Netherlands has published its Annual Report for 1995, and the EPPO Secretariat has noted the following items:
1) After the discovery of two outbreaks of Cacoecimorpha pronubana (EPPO A2 quarantine pest) in a garden of the Zeeland province (EPPO RS 94/193), surveys were carried out by using pheromone traps. In 1994, it became clear that the species had actually established in public and private gardens in different places in the Netherlands (Zeeland, Zuid-Holland, Utrecht, Noord-Brabant and Limburg). In 1995, surveys were continued to establish possible host plant preferences. It was found that C. pronubana could develop on at least 22 different plant species belonging to 9 families (Asteraceae, Berberidaceae, Caprifoliaceae, Eleagnaceae, Euphorbiaceae, Lamiaceae, Oleaceae, Rosaceae, Saxifragaceae).
2) Cryphonectria parasitica (EPPO A2 quarantine pest) was found in the southern part of the Netherlands near Belgium. However, it is felt that the infection was most probably carried by plant material from southern Europe. The Dutch Plant Protection Service has destroyed the infected plants and since then C. parasitica has not been found again in the Netherlands.
3) Discula destructiva, the causal agent of dogwood anthracnose, has been isolated from leaves on an ornamental dogwood bush (Cornus kousa var. chinensis). So far, this fungus has not been reported from Europe, but is known to cause serious damage in USA on Cornus nuttallii (Pacific dogwood) and C. florida (flowering dogwood). A review on this disease has recently been made by Daughtrey et al. (1996) on the situation in North America. Dogwood anthracnose was first observed in US in the mid-1970s, in the areas of New York city and Seattle. It then spread rapidly and its impact is rated as considerable. D. destructiva caused dieback and disfigurement of landscape specimens as well as mortality of trees in forests. The authors noted that considering its first appearance near ports of entry, its rapid spread, and its lethal nature, D. destructiva could be an introduced pathogen. However, its origin remains unknown. Very little information is available on the susceptibility of European dogwoods (C. mas and C. sanguinea) and on C. stolonifera (North American species grown in Europe), but the Dutch report stressed that as C. florida and C. nuttallii are extensively grown in Europe, the establishment of this fungus could pose serious problems.
4) Tomato spotted wilt tospovirus (EU Annexes I/B and II/A2) has been detected 31 times in 17 different plant species. Among these, 7 ornamentals were not recorded before as host plants of the virus: Bromelia achmea, Cestrum rubrum, Eucharis sp., Lobelia valida, Oxypetalum sp., Pachypodium lamerei and Ranunculus sp.
Annual Report 1995, Diagnostic Centre, Plant Protection Service, Wageningen, Netherlands, 125 pp.
Daughtrey, M.L.; Hibben, C.R.; Britton, K.O.; Windham, M.T.; Redlin, S.R. (1996) Dogwood anthracnose. Understanding a disease new to North America.
Plant Disease, 80(4), 349-357.