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

Simulated spreading rates for WCR (Western Corn Rootworm) in selected EU countries

Simulated spreading rates for WCR (Western Corn Rootworm) in France, Germany, Italy, Austria and Belgium:

Simulating the spreading in case of introduction via Paris, WCR (Western Corn Rootworm) would have infested about 270,000ha (100 %) of maize without any containment measures after 10 years. With measures, the spreading rate per year would result in a reduced infested maize-growing area of about 21,600ha, which would represent only 8% of the infested maize-growing area without any measure in 10 years. This would be a sustainable reduction of spread in Paris area. In case of Colmar, which is in an area with high concentration of maize, the situation is different. Without any measure, about 325,000ha would be infested with the WCR after 10 years. The reduction of spreading rate is not so enormous in the Alsace region like in Paris region after 10 years and would covered a maize area of about 137,000 ha, 42% of the infested area without any measure.

The simulation model output in case of an introduction via Frankfurt am Main without containment measures showed that about 476,000ha of the maize area (100%) would be infested over a period of ten years. With containment measures applied, 23,107ha would be infested, 5% of the infested maize area over ten years. In case of Passau, the 'natural spread' calculation amounted to 358,691ha of maize (100%) infested over ten years. Containment measures could reduce the infested maize area by one third (188,419ha) of the total infested area for the same period. The results of simulation of spreading of the WCR at the two locations are different by year depending on the maize concentration in crop rotation. In the 10th year without containment measures in Frankfurt, a significant ongoing spread of 265,698ha of maize occurs. The reason for this is the high maize concentration in Northrhine-Westfalia and Lower Saxony, which supports the spreading. In Passau, the conditions for the establishment of WCR are better because the amount of maize makes it a high-risk area. Therefore, the influence of containment measures is not as strong (33%) as in Frankfurt am Main (5%) where we have only a low concentration of maize in the beginning.

Both already infested locations (Venice and Como) are in the North, in areas with high maize concentrations. Therefore, the spreading rate per year of WCR would be in each case high without any containment measures and would covered in case of Venice about 832,000ha and in case of Como nearly the same with about 839,000ha in the 10th year. These infested areas would represent already about 66% of the whole maize-growing area in Italy. Remarkable is that in the 6th year in Venice and Como, the maximum infested maize-growing area would be already reached in the considered period. The infested maize-growing area in Venice would be reduced by one third (about 548,000ha) with containment measure after 10 years. In case of Como, the calculated amount of infested maize-growing area with measures would be with 471,000ha little bit more than one half (56%) of the area without any measure in one decade.

The simulated spreading scenarios of WCR have as result a potentially infested maize-growing area of 178,000ha in case of Linz and about the same (176,000ha) in case of Kittsee without any measure in the 10-years-period. Nevertheless, the influence of measures could be different depending on the maize-growing situation in both regions of Austria. In case of Linz, the infested maize-growing area would cover about 65,000ha which represents 36% of the potentially infested maize-growing area without any reduction of the spreading rate. In case of Kittsee, containment measures would have much more sustainable influence on the infested maize-growing area: only 1,000ha maize would be infested by the WCR, less than 1% of the potentially infested maize-growing area without any measure. In Burgenland region, maize concentration is low and the realisation of containment measures like crop rotations is relatively easy to implement into agricultural practice.

A relatively small country, but green and silage maize are of relatively great importance, the calculated spreading rate would lead to a fast infestation of all maize-growing areas (about 202,000ha) within the 7th and 6th years in Brussels respectively Arlon (201,000ha for both locations) according to simulation scenarios. But possible containment measures would not have the same influence in case of Brussels and Arlon. In case of Brussels, an infested maize-growing area of 80% (161,000ha) was calculated for the 7th year and of 92% (185,000ha) for the 10th year. Containment measures in case of Arlon have sustainable influence on the spreading rate and would cover an infested area of 3,800ha (2%) after 6 years and 13,000 ha (6%) after 10 years. Percentages refer to the area infested when no containment was carried out.


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