Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Potential damage assessment of WCR (Western Corn Rootworm) based on Canadian long-term data

In the USA, corn rootworms cause one billion US$ for treatment costs and crop losses per year. Corn rootworm infestations have been shown over a longer time to decrease yields of maize by 10-13%. For Europe, the potential damage of WCR (Western Corn Rootworm) for grain maize & CCM and for silage maize in Europe was calculated separately.

The average yield of grain maize & CCM and silage maize in the 7 mentioned EU member states (France, Germany, Italy, Austria, the Netherlands, Belgium and Luxembourg) and Switzerland amounted to 93.9dt/ha and 444.9dt/ha, respectively. The greatest yields were reached by Belgium/Luxembourg with 108dt/ha of grain maize & CCM and by Italy with 527.3dt/ha of silage maize.

In case of the establishment of WCR, an average potential loss of 9.39dt/ha grain maize & CCM and 44.49dt/ha of silage maize would correspond with the yield. The greatest potential loss per hectare is expected in Belgium/Luxembourg (10.8dt/ha) for grain maize & CCM and in Italy (52.73dt/ha) for silage maize.

For grain maize & CCM, the absolute potential loss would amount to 1,072,610 t for the 8 above-mentioned countries and more than 1 million t for the 7 EU member states. Because of the largest high-risk areas in Italy for grain maize & CCM, the potential yield loss would be the highest with 518,803t. That would 48.4% of the total potential loss in grain maize & CCM of all the countries. This amount of potential yield loss of grain maize & CCM is followed by France with 368,552 t (34.4 %) and Germany with 113,145t (10.5%). In Switzerland the potential loss would be low (899t) because of the low concentration of grain maize & CCM in crop rotation. In Luxembourg (no high-risk areas), no economic yield reduction is expected.

For silage maize, the potential yield loss for the 8 mentioned countries would be twice as high (2,020744t) as that for grain maize & CCM. This is the result of higher yield and higher potential yield reduction in silage maize and not of larger high-risk areas. Also for the 7 EU member states the amount would be higher than 2 million t of silage maize. Especially for Germany, the potential yield loss of silage maize would reach 930,946t (46.1% of the total potential loss in silage maize) and so the highest reduction followed by the Netherlands with 649,877t (32.2%) and Belgium with 217,696 t (10.8%). For the same reason like for grain & CCM for Luxembourg and Switzerland, the potential yield reduction of silage maize is zero and about 15,000t, respectively.


Peter BAUFELD, (Scientist)
Tel.: +49-332-0348276
Fax: +49-332-0348385