How to feed the world
A very interesting New Scientist article gives four suggestions for increasing food production - genetic modification isn't included:
1. Hold on to water
2. Stop ploughing
3. Go back to basics
4. Boost yields
You'll have to go to the article for elaboration. Under 'boost yields" there is this, however:
The yields of new varieties of maize are climbing twice as fast as yields of rice and wheat. This is because maize is bred mainly by private companies, which invest $1.5 billion a year in it. Wheat and rice breeding, by contrast, is done mostly in government labs. Wheat gets only about $350 million a year. Apart from Chinese hybrid rice varieties, rice yields have been stagnant for years.
Score one for private enterprise.