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The integration of mechanical and chemical weed control in winter cereals - CE0614

Description
Mechanical weed control in combinable crops currently results in both the crop and weeds being cultivated. Hence, the need to maintain crop safety results in insufficient damage being inflicted on weeds. The challenge is to develop principles for an integrated weed strategy where mechanical hoes can be used between crop rows at commercially viable speeds so as to achieve high levels of weed control with minimum commercially viable speeds so as to achieve high levels of weed control with minimum or no crop damage. Overall application of sub-lethal doses of herbicide may still be required to pre-dispose weeds to mechanical damage. Weeds in the crop row may be controlled by targeting herbicides to the crop row through herbicide seed dressings or granules applied at drilling. The strategy has the potential to maintain weed control costs while reducing herbicide use dramatically. It may also lead to increased sustainability of intensive rotations by preventing the development of herbicide resistance in weeds.

Recent preliminary work by Silsoe Research Institute (SRI) at ADAS Boxworth has
shown that it is feasible to use the computer analysis of video images to locate the position and orientation of crop rows in cereals. Glasshouse investigations at ADAS Boxworth (in ROAME CE0606) have also identified the type of mechanical damage that is required to kill weeds with different morphology and size and have also identified herbicides, which is seed dressings or granules will control weeds within crop rows. Long Ashton Research Station (LARS) have identified the doses of herbicides which can be used to pre-dispose weeds to mechanical control.

These different approaches need to be co-ordinated into an integrated approach where herbicide seed dressings or granules control weeds within the crop row and vigorous mechanical cultivation controls weeds between the crop rows. The mechanical weed control may require a previous overall application of herbicide to pre-dispose the weeds to mechanical control. The strategy should result in the maintenance of yields and margins with very significant reductions in herbicide usage
Objective
To provide revised, rational and cost-effective strategies for the control of grass and broad-leaved weeds in winter cereals, leading to the reduced use of herbicides.

Develop a co-ordinated research strategy with SRI and LARS.

Refine dose of seed dressings in the glasshouse and determine in the field the crop safety and field efficacy in winter wheat of different approaches to herbicide seed dressings and granules, using herbicides identified in glasshouse research.

Confirm the effect of different row spacings an use of sown bands, rather than narrow rows, on yield winter wheat.

Evaluate an integrated approach to mechanical and chemical weed control in field trials exploiting machinery developments at SRI and data on reduced herbicide doses from LARS.
Project Documents
• Final Report : The integration of mechanical and chemical weed control in winter cereals   (845k)
• Final Report - Annex : The integration of mechanical and chemical weed control in winter cereals   (1059k)
Time-Scale and Cost
From: 1997

To: 2001

Cost: £243,044
Contractor / Funded Organisations
ADAS UK Ltd.
Keywords
Arable Farming              
Cereal Production              
Farming              
Sustainable Production              
Weed Control              
Weeds              
Fields of Study
Arable Crops