THE SPREAD of disease in crops could be better detected using a mathematical modelling method developed at the University of Salford.
Levels of pathogens in plants vary greatly and may be nothing to worry about or could be the seed of the next epidemic, devastating harvests and costing farmers millions of pounds.
Now, Dr Stephen Parnell, of the School of Environmental and Life Sciences, has come up with a mathematical model which offers “an initial idea” of where and when farmers should concentrate their vigilance to keep their crops safe.
The research, published in Proceedings of the Royal Society B, is timely given a rise in the number of invasive pathogens, such as the virulent bacterium Xylella fastidiosa which has badly hit olive plantations in southern Italy and Corsica.
“Surveillance efforts have been getting increasing attention because early detection is crucial in order to control these epidemics,” Stephen told the BBC. “If you want to have a chance of controlling them or getting rid of them then you really have to catch them at a very early stage.”
His co-authored model is conceived to establish at what incidence a problem can be detected, allowing businesses and authorities to adjust their surveillance effort to where it is most effective.
There is currently very little information about how well detection efforts were likely to perform in terms of finding invasive pathogens, he said.
“This model is giving just a little more evidence to support and help inform how much surveillance needs to be done for certain disease threats,” Dr Parnell said.
“The benefit of this approach is that it is very simple. The only information you need about the epidemic is an estimate of what we call ‘epidemic growth rate’, that is once the epidemic invades, how quickly does it increase over time?”
Stephen is a lecturer in Spatial Epidemiology, who completed a PhD in mathematical biology at the University of Cambridge. He works closely with international bodies such as Defra, the US Department of Agriculture and the European Food Safety Authority.
