Der Einfluss von reduzierter Bodenbearbeitung und Zwischenfrüchten auf die Unkrautsamenbank nach ökologischem Winterweizen- und Kartoffelbau

Summary

Conservation agriculture is one answer to counteract problems that are arising with climate change and soil degradation since the period of agricultural intensification. The main objectives of conservation agriculture are reduction of tillage intensity and a
permanent soil cover by cash and cover crops. However, increased weed infestations are frequently reported in minimum tillage systems, particularly under organic
management, resulting in increased weed seed banks.
In two field experiments introduced in 2010 and 2011 and starting with two years grass-clover followed by winter wheat and potatoes, we evaluated the effect of chisel
ploughing with mulch application to potatoes and different cover crops after winter wheat on the weed seed bank. Therefore, soil cores were taken before sowing wheat
and after potato harvest and the viable weed seed bank from soil samples was assessed over a nine month period. Our results suggested a strong influence of weather conditions resulting in decreased and increased weed seed banks in the first and second experiments, respectively. Furthermore, winter wheat was confirmed as the main contributor of weed seeds to the seed bank resulting in dominances of winter
annual weeds.