Incursion of Diaphania perspectalis in Germany and addition to the EPPO Alert List
The NPPO of Germany recently informed the EPPO Secretariat of the incursion of Diaphania perspectalis (Lepidoptera: Pyralidae) in Baden-Württemberg. In May 2007, heavy damage on Buxus plants (mainly B. sempervirens) was observed in the city of Weil am Rhein and its surroundings. Damage was caused by larval feeding on leaves and shoots, leading to almost complete defoliation of Buxus hedgerows. Because of the high infestation level, it was assumed that this insect was introduced several years ago (probably around 2005). D. perspectalis originates from Asia and is known to occur in Japan, China and Korea Republic. It is assumed that it was introduced into Germany with commodities from China, since there was an important shipping centre for commodities imported from China close to the infested area. So far, the infestation is being controlled by insecticide treatments. On the basis of a preliminary risk assessment, the NPPO of Germany considered that D. perspectalis presented a high risk potential for Southern and Western Europe. Therefore, the EPPO Secretariat felt that this pest could be added to the EPPO Alert List.
The pest status of Diaphania perspectalis in Germany is officially declared as follows: Transient, actionable, under eradication.
Diaphania perspectalis (Lepidoptera: Pyralidae)
Why: Diaphania perspectalis (synonym Glyphodes perspectalis) is a pest of Buxus originating from Asia which was reported for the first time in 2007 in Europe, in Germany. Although data is lacking on the biology, geographical distribution and economic impact, D. perspectalis is apparently able to cause severe defoliation to Buxus plants.
Where:
EPPO region: Germany (Baden-Württemberg). D. perspectalis was found in May 2007 in the city of Weil am Rhein and its surroundings. Eradication measures are being implemented in Germany.
Asia: China, Japan, Korea Republic.
On which plants: Buxus species (e.g. B. microphylla, B. microphylla var. insularis, B. sempervirens, B. sinica).
Damage: Larvae feed on leaves and shoots and severe infestations can lead to almost complete defoliation of the plants. Data is lacking on the biology of the pest but in China (Shanghai), 3 to 4 generations per year have been observed with 6 to 7 larval instars. Larvae pupate on the leaves.
Pictures can be viewed on the Internet:
http://www.lepiforum.eu/cgi-bin/lepiwiki.pl?action=browse&id=Glyphodes_Perspectalis&revision=9
http://www.klaus-rennwald.de/neubuerger/index.html
http://nafoku.de/butfly/htm/17102007_0836.htm
Dissemination: Adults can fly but no data is available on the natural dispersal of this insect. Trade of infested Buxus plants or parts of plants can disseminate the pest over long distances. In Germany, it was observed that D. perspectalis was found in the vicinity of a shipping centre for commodities imported from China, so it might be possible that the pest could also be transported as a hitchhiker on various commodities.
Pathway: Plants for planting of Buxus.
Possible risks: Buxus are commonly planted in European gardens (parterres, hedges, topiary work) and are also growing in forests as understorey shrubs. Severe attacks of D. perspectalis can lead to defoliation and therefore completely disfigure Buxus plants which in many cases are grown for ornamental purposes. Although data is lacking on the control of D. perspectalis, chemical and biological control methods (e.g. with nematodes such as Steinernema sp.) are mentioned in the literature. The introduction of such a new pest in Europe could represent a threat to nurseries, parks and gardens, and Buxus shrubs growing in the wild.
EPPO RS 2007/215
Panel review date - Entry date 2007-11
Sources
Bin-Cheng Zhang (1994) Index of economically important Lepidoptera. CABI Wallingford, GB, 599 pp.
CABI Crop Protection Compendium. http://www.cabicompendium.org/cpc/
Maruyama T (1993) Life cycle of the box-tree pyralid, Glyphodes perspectalis (Walker) (Lepidoptera: Pyralidae). IV. Effect of various host plants on larval growth and food utilization. Japanese Journal of Applied Entomology and-Zoology 7(3), 117-122 (abst.).
NPPO of Germany, 2007-07.
Tang SJ, Qin HZ, Sun W (1990) Studies on bionomics of Diaphania perspectalis. Journal of Shanghai Agricultural College 8(4), 307-312 (abst.).
Zhou-Wei, Xia-CaiYun, Sun-XingQuan, Zhu-Bing, Liu-XiaoPing, Liu-ZhiCheng, Wang-Yan (2005) Studies on the biological characteristics and control of Diaphania perspectalis Walker. Journal of Shanghai Jiaotong University Agricultural Science 23(1), 52-56 (abst