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Assessment of the availability of seed on the soil surface after drilling - PS2334

Description
EU Directive 94/414 requires that plant protection products have no unacceptable effects on the environment, particularly on non-target species and Defra Pesticides Safety Directorate (PSD) is responsible for assessing the environmental safety of pesticides in the UK.
For seed treatments the risk assessment includes an intake calculation which assumes that the bird or mammal consumes only treated seeds found after drilling on the surface of the field. This requires calculation of both the number of seeds required to reach a median lethal dose or NOEC and the area over which birds and mammals would have to forage to obtain that intake. In including the role of incorporation and in particular incorporation efficiency, data from the Netherlands (DeSnoo and Luttik 2004) is used; there is very limited data available for the UK. The Dutch data gives an overall incorporation efficiency of 99.5% for precision drilling, 96.7% for standard drilling in spring and 90.8% for standard drilling in autumn. This is generally translated to the availability of seed across the whole field. However, there were wide variations between headlands and the field centre and on average there were 2 spills per field. Project PS2328 is assessing the use of newly drilled fields, primarily cereals, by birds and mammals. This proposal relates to an additional project to assess the numbers of seeds on the surface in relation to soil type and agronomic practice. It is known that the availability of seeds is affected by agronomic practice, e.g. if headlands are planted first or last.

The aim of this project is to build upon the work undertaken in PS2328 and
(a) Assess the availability of seeds post-drilling on the surface of fields
(b) Assess the relationship between soil structure and seed availability
(c) Assess the data in relation to that published by DeSnoo and Luttik (2004) for the Netherlands to assess applicability.
(d) Determine the average seed available per m2 for a range of arable crops on the field and headlands
The crops identified are winter wheat, spring wheat, barley, oilseed rape, sugar beet and maize. The results will assist PSD by providing better information about the importance of these exposure routes and enable them to determine whether improved estimates of exposure and guidance on data requirements are required. These will lead to improved risk assessment procedures and hence iimprove the understanding of potential for risk to wildlife from pesticide use.

Objective
1. Assess the availability of seeds post-drilling on the surface of fields
2. Assess the relationship between soil type and seed availability
3. Assess the data in relation to that published by DeSnoo and Luttik (2004) for the Netherlands to assess applicability.
4. Determine the average seed available per m2 for a range of arable crops on the field and headlands

Project Documents
• Final Report : Assessment of the availability of seed on the soil surface after drilling   (3904k)
Time-Scale and Cost
From: 2007

To: 2009

Cost: £75,486
Contractor / Funded Organisations
Central Science Laboratory
Keywords
Agricultural Land              
Animals              
Application              
Birds              
Food and Drink              
Mammals              
Pest and Weed Control              
Pesticide use              
Pesticides              
Plants and Animals              
Fields of Study
Pesticide Safety