The spike in global food prices in 2007�08 not only led to riots on several continents; it also reawakened fears about the world�s future ability to feed itself, as growing populations place greater demands on agricultural systems operating in increasingly difficult environmental and climatic conditions.

With more than half the world�s people and high levels of inequality, Asia lies at the centre of the global food-security challenge of the twenty-first century. The region � especially China and India � is drawing on world stocks and importing more staples, as its own farms strain...