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Integrated weed management in winter cereals - herbicide dose selection - CE0613

For economic and environmental reasons, particularly the need to minimise the risk of contaminating water, there is a urgent requirement for weed management techniques that use less herbicide. In cereals, mechanical weed control plus very low does of herbicide to predispose the weeds to cultivations and to prevent regrowth shows promise. However, the severity of overall spring time cultivations required to kill weeds often results in crop damage. Recent work at SRI has shown electronic devices can be used to locate the position and orientation of crop rows in cereals thus allowing intensive and effective weed mechanical control between rows (CE0615). The most effective exploitation of this technique may still require overall application of sub-lethal doses of herbicide (CE0613). Weed s within the rows may be controlled with herbicides applied as seed dressings or granules and this approach will be developed at Boxworth in Project CE0614.

Information on the effects of growth stage and weather factor s enables selection of spray window when herbicide does can be cut with minimum risk of failure and equally important gives indications when the full dose should be used to achieve reliability. This research will provide a rational basis for making economies in herbicide use in 1) conventional overall spray, 2) overall spraying integrated with mechanical cultivation and 3) narrow band herbicide treatments within rows. The benefits of reduced doses are mainly environmental for older low cost high use rate herbicides such as clodinofop. For all herbicides reduced doses combined with mechanical weed control are likely to reduce the incidence of herbicide resistance. Results on blackgrass and wild oats will complement the ADAS project “the improved management of grass weeds in cereals” (CE0612) as well as CE0614.

The target weeds for the herbicide studies are highly competitive with winter cereals and difficult to control by mechanical cultivations; the grass weeds are wild oat and blackgrass and the broadleaved weeds cleavers, poppies, mayweed and volunteer rape.
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 and protocols with ADAS and SRI.

Define the optimum growth stage and weather conditions for chemical control of:
Black-grass and wild-oats with clodinofop and DPX KE459
Cleavers, poppies, mayweed and volunteer rape with tribenuron and amidosulfuron. By March 1999.

Develop rational approaches for using sequences and mixtures of the best herbicides selected in sub-objective 2 to ensure a minimum quantity of active ingredients is used to control a broad and diverse spectrum of weed species. By August 1999.

Make recommendations based on sub-objectives 2 and 3, for wider-scale field experimentation in CE0614 and IACR-LARS LIFE programme.
Project Documents
• Final Report : Integrated weed management in winter cereals - herbicide dose selection   (38k)
Time-Scale and Cost
From: 1997

To: 2001

Cost: £156,000
Contractor / Funded Organisations
Rothamsted Research (BBSRC)
Arable Farming              
Cereal Production              
Herbicide use              
Sustainable Production              
Weed Control              
Fields of Study
Arable Crops