ROME — The United Nations Food and Agriculture Organization (F.A.O.) published a discussion paper on Sept. 23 stating that the main challenges world agriculture will face in the coming decades are producing 70% more food for an additional 2.3 billion people by 2050, while at the same time combating poverty and hunger, using scarce natural resources more efficiently and adapting to climate change.

The F.A.O. said it will organize a High-Level Expert Forum in Rome on Oct. 12-13 to discuss strategies on "How to Feed the World in 2050." The forum will bring together approximately 300 leading experts from academic, non-governmental and private sector institutions from developing and developed countries.

The forum will lay the groundwork for the World Summit on Food Security, to take place in Rome Nov. 16-18.

The demand for food is expected to continue to grow as a result of population growth and rising incomes. Demand for cereals (for food and animal feed) is projected to reach approximately 3 billion tonnes by 2050. The F.A.O. estimated annual cereal production will have to grow by almost 1 billion tonnes, and meat production by more than 200 million tonnes to reach a total of 470 million tonnes in 2050, 72% of which will be consumed in developing countries, up from the 58% today.

"F.A.O. is cautiously optimistic about the world's potential to feed itself by 2050," said Hafez Ghanem, assistant director-general for the F.A.O. He pointed out that feeding everyone in the world by then will not be automatic and several significant challenges have to be met.

Mr. Ghanem said there was a need for a proper socioeconomic framework to address imbalances and inequalities and ensure that everyone in the world has access to the food they need and that food production is carried out in a way that reduces poverty and takes into account natural resource constraints.

The F.A.O. said global projections show that in addition to projected investments in agriculture, further significant investment will be needed to enhance access to food, otherwise some 370 million people may still be hungry in 2050, almost 5% of the developing countries’ population.

According to the latest U.N. projections, world population will rise to 9.1 billion in 2050 from 6.8 billion in 2009. The U.N. said nearly all of the population growth will occur in developing countries. Sub-Saharan Africa’s population is expected to grow the fastest (up 108%, 910 million people), and East and South East Asia’s the slowest (up 11%, 228 million).

The U.N. estimated that around 70% of the world population will live in cities or urban areas by 2050, up from 49% in 2009.