I'm Nichola Hawkins from Rothamsted Research,
and I'm going to be talking about the evolution of
pesticide resistance in crop protection.
My own research focuses on fungicide resistance in plant pathogens,
but there are a lot of common themes across pesticide groups.
I'll start by introducing the problem of resistance,
then talk about research, monitoring resistance,
identifying the molecular mechanisms of resistance,
and investigating the underlying evolutionary biology leading to resistance.
This is growing public awareness now of the threat posed
to human health by antibiotic resistance in medicine.
The superbug MRSA has a death rate of two-thirds
higher than drug-sensitive staphylococcus infections.
Drug-resistant E. coli has double the death rates of sensitive types,
and nearly half a million cases of
drug-resistant TB have been reported globally within one year.
Resistance evolves when genetic variation in a population of
microbes includes differences in antibiotic sensitivity.
When an antibiotic is used,
the most sensitive bacteria will kill at a higher rate than the resistant bacteria.
Then, when the surviving bacteria reproduce,
more of them will pass on the resistance genes to their offspring.
So, an increasing proportion of the population will be resistant.
The resistance threat extends beyond antibiotics.
We see a similar situation for other biocidal drugs:
antivirals and antiretrovirals, antifungals, and antiparasitics.
We see malarial parasites resistant to antimalarials,
but also mosquitoes resistance to the insecticides used in vector control;
also, the evolution of anticancer drug resistance
where resistant mutants are selected at the cellular level.