Reducing weed infestation in winter wheat by sowing technique

Summary

Hoeing can improve weed control in cereals but this requires wider row spacing of the crop. A spe-cific band row design may also ensure high crop yield and quality, especially at the conditions of organic farming. In order to study those effects two field experiments with winter wheat were con-ducted in 2005 and 2006 at the organic farming research area of the BBA. Three different row de-signs have been investigated: narrow (100 mm spacing), wide (400 mm) and band sowing (alternat-ing of crop band of 400 mm and a crop-free band of 300 mm width). All plots were harrowed whereas the wide and band sown plots have additionally been hoed. Also two cultivars differing in growth habit and competitiveness were tested (Ludwig, Pegassos).
Neither harrowing nor the combination of harrowing and hoeing could reduce weed density (by analysing data before and after treatments). Also the different row spacing had no effect on weed density at late spring (257 weeds m-2). However, weed growth at the same time was clearly influenced by the row spacing: Weed biomass was significantly higher in the plots with wide rows (23.1 g m-2) compared to normal (8.3 g m-2 ) and band sowing (10.5 g m-2 ). Crop yield was highest at band sowing (7.09 t ha-1) whereas the wide sown crop stand was of significant lower yield (6.18 t ha-1) but highest protein content (10%). Regarding cultivar effects Pegassos was more competitive against weeds and provided also a higher yield than cultivar Ludwig.
So far, band sowing has been proved as an easily applicable sowing technique which enables the use of hoes in cereals and ensure high crop yield especially at conditions of organic farming.