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Economic and agronomic analysis of reducing the risk of slug induced crop losses by increasing crop seed rate - PS2821

Description
Determining non-chemical methods for controlling slugs is extremely important to reduce the reliance on molluscicide pellets. Slugs are able to reduce crop yield by reducing the plant population to below the minimum number of plants/m2 required to achieve potential yield. Slugs reduce the plant population by hollowing seeds or by destroying the developing seedling. Winter wheat and winter oilseed rape are the crops which commonly suffer the most damage from slugs.

One possible way to reduce the potential for slugs to decrease yield would be to increase the seed rate at which winter wheat and oilseed rape are sown. Experiments have been carried out in the past, including those performed in a previous CRD funded project (PS2805), which have determined the economically optimum plant population for both winter wheat and oilseed rape. For winter wheat this ranged from between 72 and 195 plants/m2 in 23 cases, and was more than 400 plants/m2 in two cases. For oilseed rape the economically optimum plant population was between 13 and 48 plants/m2 in 14 cases, and between 63 and 159 plants/m2 in four cases in 2011 when there was a very severe spring drought which restricted plant compensatory growth. Knowledge of commercial winter wheat and oilseed rape seed rates along with crop establishment information suggests that at current seed rates the ability for crops to tolerate plant losses caused by slug damage may be small. Increasing seed rate may therefore be an alternative to molluscicide use.

There will obviously be costs associated with increasing seed rates and these include: the increased cost of seed, an increased lodging risk and increased take-all infection in 2nd and subsequent wheats. It is possible that there may be additional penalties associated with increasing seed rate and these will be fully investigated through a literature review here.
Aim
Carry out an economic and agronomic analysis of using higher crop seed rates to reduce the risk of slug induced crop losses
Objectives
1) Collate existing seed rate response experimental data for winter wheat and winter oilseed rape.
2) Quantify the economic impact of using different seed rates in scenarios with different levels of slug pressure
3) Assess the potential impact of changing seed rates on factors which are less easy to quantify including; even ripening, damage from non-slug pests, take-all and other diseases.
4) Assess the cost effectiveness of using slug pellets
5) Compare the cost effectiveness of using higher seed rates to minimise yield losses from slugs against using slug pellets.






Objective
The overall aim of the project is to carry out an economic and agronomic analysis of using higher crop seed rates to reduce the risk of slug induced crop losses.

The specific objectives are as follows:
1) Collate existing seed rate response experimental data for winter wheat and winter oilseed rape.
2) Quantify the economic impact of using different seed rates in scenarios with different levels of slug pressure.
3) Assess the potential impact of changing seed rates on factors which are less easy to quantify including; even ripening, damage from non-slug pests, take-all and other diseases.
4) Assess the cost effectiveness of using slug pellets.
5) Compare the cost effectiveness of using higher seed rates to minimise yield losses from slugs against using slug pellets.
Project Documents
• EVID4 - Final project report : PS2821 Final report   (797k)
Time-Scale and Cost
From: 2013

To: 2014

Cost: £15,000
Contractor / Funded Organisations
A D A S UK Ltd (ADAS)
Keywords
Agriculture              
Cereals              
Farm Management              
Molluscs              
Oilseed Rape              
Pest Control              
Sustainable Farming and Food              
Fields of Study
Pesticide Safety