Download CLIMATE CHANGE AND RANGE SHIFT OF IGUTETTIX OCULATUS

CLIMATE CHANGE AND RANGE SHIFT OF IGUTETTIX OCULATUS
Huusela-Veistola, E.1 and Söderman, G.2
1MTT Agrifood Research Finland, Plant Production Research, Finland; 2Finnish Environment
Institute,
Natural Environment Centre, Biodiversity Unit, Finland
E-mail: [email protected]
The leafhopper Igutettix oculatus (Lindberg) is a new arrival in Finnish fauna. I. oculatus has
adapted to live on lilacs Syringa sp.. The nymphs and adults feed sap on the underside of the
lilac leaves and can cause substantial discoloration. Although yellowing of leaves seems to
cause no harm to the growth of the lilacs, cosmetic damage and reduction of market value are
obvious.
I.oculatus originated from the east Palaearctic and has most probably been introduced with
lilac plants to Moscow and the St. Petersburg region in European Russia. Its expansion into
Finland is likely to be natural. It is first found in Kouvola, south-east Finland, in 1999.
Nowadays, it has dispersed to many ornamental gardens in south Finland and is actively
spreading onwards. Widening of the distribution area further west- and southward in Europe is
quite possible.
The future expansion of the leafhopper is not hampered by the host plants, as they are
commonly cultivated as garden and park plants.
The females oviposit into leaf buds in late autumn and the species hibernates in the egg stage.
The nymphs of the first generation occur in early June, and adults in late June and early July.
Nymphs of the second generation hatch in the beginning of August, and adults occur from the
beginning of September until early October. Only part of the second generation reach adult
stage, because many individuals still are in the last nymphal instar at the onset of leaf fall
caused by night frosts. Population growth and expansion to the north is limited by early
nightfrosts,
but along with climate change the pest status and distribution of species could expand.
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NJF Report • Vol 6 • No 1 • Year 2010
NJF Seminar 430
Climate Change and Agricultural Production in the Baltic SeaRegion
- Focus on Effects, Vulnerability and Adaptation
Uppsala, Sweden, 4-6 May 2010
Nordic Association of Agricultural Scientists