An analysis of the potential for improving seed quality in oilseed rape as a basis for optimising establishment

Abstract

The establishment period of rape is crucial. Too few plants will restrict canopy expansion during autumn, reducing growth and the ability of the crop to compete with weeds and pigeons.

Patchiness exacerbates the problem by reducing the uniformity of crop growth and development leading to less uniform ripening, often necessitating the greater use of pre-harvest desiccants. In extreme cases, total crop failure requires crops to be re-sown or the cropping sequence to be changed.

Crops of winter rape are particularly at risk during a six month period from September to February and in the worst years, establishment can be so poor that up to 30% of rape crops have been abandoned. Plant failure during establishment has often been associated with poor seedbeds because almost three quarters of the oilseed rape grown is drilled into clay soils, and it is on these soils, especially where cereal residues have to be incorporated, that seedbed preparation is difficult and crop failure most likely to occur.