Einfluss des Anbausystems auf Ertrag und Gesundheit von Winterweizen

Summary

In a long-term trial in central Switzerland, yield and health of winter wheat was
examined under organic, extensive and intensive management.
In the organic cropping system, soil was ploughed and fertilised with cattle dung. In
the extensive system, soil was cultivated ploughless and dung was supplemented by
mineral fertiliser. Herbicides were used, but no growth regulators or fungicides. In the
intensive system, soil was ploughed and manure was based on cattle dung and
mineral fertiliser with 20 % more nitrogen than in the extensive system. For plant
protection, herbicides, growth regulators and fungicides were used.
In the period from 2004 to 2007, average winter wheat yields of the intensive and the
extensive crop management system exceeded those of the organic production by 21.3
% and 5.5 % respectively. This was probably due to the higher level of fertilisation and
plant protection.
In 2007, a year with frequent rain during the summer, the infestation of grains with
Microdochium nivale and Fusarium graminearum was lowest in the organic wheat. In
consequence, its germination capacity was higher and the deoxynivalenol content was
lower compared with the other systems. The increased grain infestation with F.
graminearum and the higher deoxynivalenol content of wheat grains in the extensive
system can be explained by the ploughless tillage, with straw from the previous maize
crop remaining on the soil surface.