Gesunde Pflanzen (2010) 62, 1-9
K. Hanzlik and B. Gerowitt (2010)
Verändern pfluglose Bodenbearbeitung und Frühsaaten die Unkrautvegetation im Winterraps?
[Does non-inversion tillage and early sowing influence weed populations in oilseed winter rape?]
Gesunde Pflanzen 62 (1), 1-9
Abstract: Between 2005 and 2007 a total of 1364 oilseed rape (OSR) fields in 12 federal states of Germany was surveyed. Investigations took place in late autumn and included the identification and counting of all weeds in unsprayed parts of rape fields. Results on the impact of tillage intensity and crop sowing date on the level of total weed infestation, weed species number and weed flora composition in OSR fields are shown and those species identified which are sensitive to the analysed factors.
Neither tillage intensity nor crop sowing date affect the level of weed infestation in OSR fields. In contrast, species richness was enhanced by non-inversion tillage as well as by an early crop sowing. While there were statistically proofed differences in the weed species composition of ploughed and unploughed OSR fields due to canonical correspondence analysis, the crop sowing date only had minor effects on species composition. Nevertheless, a multitude of single weed species was affected by tillage intensity and sowing date showing significantly differing relative frequencies and/or densities in fields with inversion and non-inversion tillage as well as between early and late sown crop. Among others Centaurea cyanus, Anchusa arvensis, A. spica-venti and Elymus repens were more abundant and partly reached higher densities after ploughing, whereas non-inversion tillage mainly favoured Galium aparine, Geranium spp. and Sisymbrium spp.. Lots of weed species tended to have higher populations when OSR was sown before August 15th, species significantly increased by early sowing date were e. g. Centaurea cyanus, Convolvulus arvensis, Euphorbia spp. and Anchusa arvensis. However, only V. arvensis reached significantly higher densities when OSR was sown after September 1st.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: German)
Link to article at publishers website
Database assignments for author(s): Bärbel Gerowitt
Research topic(s) for pests/diseases/weeds:
environment - cropping system/rotation
