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Biology and population dynamics of weeds in cereals and other arable crops - CE0611

Studies of the population biology of weeds are needed to provide basic information to underpin weed control strategies, particularly those aimed to reduce herbicide inputs. Understanding the longer term consequences of weed control strategies is vital to support the development of more integrated weed management practices. Our lack of knowledge of the population dynamics of weeds is constraining our ability to optimise inputs.

In order to provide the basic information needed, studies are required of the basic biology of major weeds, which will include the production and fate of weed seeds in crops, their dormancy/viability and their short and long term survival in the soil.

Over 30 species may occur as important weeds in the UK and it is not possible to study them all. Species need to be selected on the basis of their importance to agriculture and on their potential to represent a number of other species with similar phenology and growth habit.

As weed distributions are not random, but are aggregated, there is potential to reduce weed control inputs by only treating the weed patches. Such techniques require underpinning with basic information on the ecology of weed patches.

The information from this programme needs to be integrated into overall long term weed management strategies that combine data on the ’need for control’ (population dynamics and competition) with achieving that need (targeted weed control). This would be best achieved through a weed control Decision Support System.
1) To measure weed seed production by seven key weeds of autumn-sown crops (wild-oats, black grass, sterile brome, chcikweed, cleavers, common field-speedwell, scentless mayweed), representative of the major weed types to occur in these crops. Research to concentrate on winter wheat. Investigate the viability and dormancy of the seeds produced by selected species. Work on other important species (e.g. filed pansy, red dead-nettlem ivey-leaved speedwell, charlock) will be attempted, resources permitting.

2) To investiagtae seed persistence by the major arable weeds, to provide data on the longevity of weed seeds in soils. Research will concentrate on the major weeds of winter cereals and will simulate normal agricultural practises in the production of autumn-sown crops. Experiments to be established at RES and LARS.

3) To investiagate the factors governing seed loss in the critical first 3 months after production (July-October). Research to concentrate on wild-oats and cleavers; key weeds representative of both grass and broad-leaved weeds, for which we already have some data on other aspects of population dynamics. This work will provide information on the survival of seeds in relation to both weed population and dynamics and distribution.
Project Documents
• Final Report : Biology and population dynamics of weeds in cereals and other arable crops   (108k)
• Final Report - Annex : Biology and population dynamics of weeds in cereals and other arable crops   (10k)
• Final Report - Annex : Biology and population dynamics of weeds in cereals and other arable crops   (7k)
Time-Scale and Cost
From: 1997

To: 2001

Cost: £787,000
Contractor / Funded Organisations
Rothamsted Research (BBSRC)
Arable Farming              
Cereal Production              
Sustainable Production              
Weed Control              
Fields of Study
Arable Crops