Die gute alte Fruchtfolge als Bekämpfungsmethode gegen den Maiswurzelbohrer (Diabrotica virgifera virgifera LeConte)

Summary

Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), the western corn rootworm
(WCR), is an immigrant from North America and one of the top ten global agricultural
pest species. Within the last 15 years, WCR invaded Europe at 3 focal points, and has
been steadily extending its domain soon threatening commercial maize production.
After the first detection in Switzerland in 2000 near Lugano, careful observations by
pheromone trap monitoring of this quarantine organism have been realized.
Experiences with WCR whose populations dynamics are incompletely understood,
have also been studied by installing a continuous maize field comparing population
dynamics with rotated maize fields in the immediate surroundings. Our experiences
with WCR populations in the Swiss territory are here briefly summarized:
1. Mandatory crop rotation in the canton Ticino slowed spread of WCR significantly.
WCR infestations north of the main Alpine mountain chain were rare and eradicated
by crop rotation. 2. In a continuous maize cropping system population of WCR can
reach economic damage level, but can also be confined by unknown factors 3.
Switzerland with its rigorous crop rotation program may serve as an example of farsighted
WCR management preserving environment and saving money.