Pest categorisation of Exomala orientalis

Abstract

The EFSA Panel on Plant Health performed a pest categorisation of Exomala orientalis (Coleoptera: Rutelidae) (Oriental beetle) for the EU. Larvae feed on the roots of a variety of hosts including most grasses and many vegetable crops. Maize, pineapples, sugarcane are among the main host plants. Larvae are particularly damaging to turfgrass and golf courses. The adults feed on flowers and other soft plant tissues (e.g. Alcea rosea, Dahlia, Iris, Phlox and Rosa). Eggs are laid in the soil. Larvae feed on host roots and overwinter in the soil. Adults emerge from pupae in the soil in May-June and are present for about 2 months. E. orientalis usually completes its life cycle in 1 year although individuals can spend two winters as larvae. Commission Implementing Regulation (EU) 2019/2072 (Annex IIA) regulates E. orientalis. The legislation also regulates the import of soil attached to plants for planting from third countries; therefore, entry of E. orientalis eggs, larvae and pupae is prevented. E. orientalis is native to Japan or the Philippine islands. It is also found in East Asia and India, Hawaii and northeastern USA. It is assumed to have reached USA via infested nursery stock. Plants for planting (excluding seeds) and cut flowers provide potential pathways for entry into the EU. E. orientalis has been intercepted only once in the EU, on Ilex crenata bonsai. Climatic conditions and the availability of host plants provide conditions to support establishment in the EU. Impacts on maize, grassland and turfgrass would be possible. There is uncertainty on the extent of the impact on host plants which are widely commercially grown (e.g. maize) Phytosanitary measures are available to reduce the likelihood of entry. E. orientalis satisfies the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union quarantine pest. Of the criteria that are within the remit of EFSA to assess for it to be regarded as a potential Union regulated non-quarantine pest, E. orientalis does not meet the criterion of occurring in the EU.