THE CAMBRIDGE STATISTICS DISCUSSION GROUP
Wednesday 30th November 2005 7:15 for 7:45
Centre for Mathematical Sciences,
Design of experiments and analysis of data
concerning GM crops
Joe Perry, Suzanne Clark Peter Rothery
Rothamstead Research, Centre for Ecology & Hydrology,
Harpenden, Herts Monks Wood
My research on GM crops has largely involved collaboration on the design and
analysis of the UK Farm Scale Evaluations of genetically modified
herbicide-tolerant (GMHT) crops. Results concerning the effects of herbicide
management practices on farmland wildlife for three spring-sown crops (beet,
spring oilseed rape and maize) were published in autumn 2003 and spring 2004;
results from the fourth crop, winter oilseed rape, were published sometime in
March 2005. A brief summary will be given of the results published to date.
Some other GM work will be summarised. Simple mathematical models can be
used to show how the adverse effects of GMHT systems on the wildlife in sugar
beet crops might be mitigated. Another study involved mathematical modelling
of relevance to the issue of coexistence between GM crops and organic or
conventional crops; this estimated the land available for planting and how
this may be affected by the separation distances proposed between GM and other
crops. Other modelling involves gene flow and demonstrates how decisions on
separation distances may be critically dependent on assumptions made for
long-distance gene flow. Further work is ongoing with Marie Castellazzi
(Rothamsted Research) within a 42-partner EU-funded project entitled
SIGMEA, in which gene flow models developed in France are to be upscaled to
the landscape level. A short description will be given of our work in this
project, to design a landscape simulator.
Joe Perry has worked at Rothamsted Research for twenty-nine years, researching
quantitative methods applied to ecology. He spent 16 years in the Statistics
Department, and moved to his current Division, of Plant & Invertebrate Ecology
in 1993. For many years he has researched methods of detecting spatial
pattern, and his SADIE system is used increasingly to measure clusters in the
form of patches and gaps in abundance and to quantify spatial association.
He was awarded a DSc degree by the University of Reading in 1989 and since
1994 he has been Visiting Professor of Biometry at the University of Greenwich.
He is currently President of the British Region of the International
His work on GM began in 1999 when he teamed up with Peter Rothery and
Suzanne Clark as part of the Consortium formed to undertake the UK’s Farm
Scale Evaluations (FSE) of Genetically Modified Herbicide-Tolerant crops.
The FSE studied the effect of herbicide tolerant systems of management on
farmland wildfile. They became the biggest study of the environmental impact
of GM crops conducted anywhere in the world and represented the only time that
scientists have evaluated the environmental impact of a new farming practice
in the UK before its introduction. When not at work Joe enjoys singing and
The main entrance is reached from Clarkson Road by going along the
footpath to the right of the Newton Institute, and turning left through the
gatehouse towards the main building (Pavilion A), which has a glass front and
a curved grassed roof. The main entrance is in the middle of the glass
front. Coffee before the talk will be in the common room in Pavilion D,
and the talk will be in Meeting Room 5 in Pavilion A. Free Parking is
available after 5pm on Clarkson and Wilberforce Roads.
Next Meetings (2006):
1st February - Stephen Duffy (Cancer Research UK).
13th March - Ian White (Biostatistics) on 'Analysing imperfect randomised
3rd April - Rebecca Turner (Biostatistics).
4th May - Adam Kleczkowski (Plant Sciences).
Supper: Some members eat regularly in the University Centre before
each talk meeting in the downstairs bar at 6pm. Feel free to join them.
Subscriptions: of 4 pounds per attender are now due for the 2005-2006 session.
Secretary: Peter Watson, MRC Cognition and Brain Sciences Unit,
15 Chaucer Road, Cambridge CB2 2EF;telephone 01223 355294 Extension 801;
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