Looking at cereal varieties to help reduce weed control inputs

Improved understanding of cereal canopy shading may allow a
reduction of inputs for weed management. A trial is described from the EU-funded Weed Control in Organic Farming (WECOF) project showing the relationship between wheat and weed ground cover through the season. Some varieties show good early planophile growth and ground cover and poor, erectophile, later cover, allowing late weed growth. Others show converse development and effect on weeds. Some have high ground cover throughout the season, giving consistently good weed suppression. The detailed development of the canopy is being modelled to assist in describing varietal ideotypes for appropriate weed suppression under different conditions. The aim is to produce variety identification guides for organic farmers who need more competitive crops, and for breeders to understand the key features of such varieties. This knowledge would also be beneficial for ICM and agri-environment schemes where there is a need to reduce herbicide use.