WCR is spreading rapidly outwards across Central and Eastern Europe. In addition to Yugoslavia, Bosnia and Herzegovina, Croatia, Hungary and Romania, it has also been found in northwestern Bulgaria, northeastern Italy and northern Montenegro. Based on the present rate and direction of its spread through the infested countries, WCR will probably find its way into other areas of Europe within the next few years. This is likely to cause economic hardship to farmers by raising their production costs and will pose greater environmental problems through the increased use of insecticides directed against this pest. WCR larvae and adult beetles can damage maize plants, although the most significant damage occurs from larvae feeding on the roots.
Larval damage can reduce the amount of water and nutrients supplied to plants, thus impacting yield.
Additionally, extensive root damage makes plants susceptible to lodging. Plants that have fallen over are difficult to harvest, especially by machine, and harvest losses occur. The adult beetles can also interfere with the pollination process. Rumania populations in Bosnia and Herzegovina, Croatia, Hungary, Romania and Bulgaria are likely to reach levels that will cause economic losses similar to those seen in Yugoslavia. Awareness creation and training of national researchers, extension personnel, farmers and pest managers to deal with this new pest were important components of this project.