Presented by Prof Iain Stewart.
Rothamsted Research is the oldest agricultural research centre in the world. It has planted wheat experiments that have been running since the 1840s.
But these days, amid worries over food security, scientists are being asked to redouble their efforts to make crops more productive and cheaper, and more sustainable to grow.
Their approach is often genetic - looking to use genetic investigation into plants to identify ways in which their cropping or resistance to pests can be enhanced. This use of GM as a 'tool' in experiment has been very successful. But the use of genetically modified crops is currently banned in Britain - something the scientists discuss.
Producer: Susan Marling
A Just Radio production for BBC Radio 4.