大象传媒

The global economic crisis has made the food situation for poor people even worse, leading to the launch of a World Summit on Food Security in Rome. Food prices remain stubbornly high in many developing countries, and the Food and Agriculture organisation of the UN has estimated that the number of hungry people could pass the one billion mark this year.

It's estimated the world will have 9 billion people in it by 2050. How will the farming industry feed them? Is the answer to grow more food at any cost, using every technical aid? There's another life-or-death issue which might stop that: global warming. The farming industry is a significant source of greenhouse gas emissions, and one of the biggest factors in that is the use of nitrogen fertilisers.

Patrick Holden of the UK's organic food movement, the Soil Association, explains why it shuns nitrogen fertilisers.

We look at possible solutions such as greener varieties of fertiliser which are being researched in the US. Dr Lewis Ziska, from the American Department of Agriculture, says that smarter use of nitrogen could reduce the global warming impact of fertilisers.

Our regular commentator Lucy Kellaway ponders on whether ruling by fear is the most effective management style.