According to current estimates on world population growth, agricultural productivity will have to increase by 56 percent by 2030. Can organics help answer this need?

That question was a topic of great interest at a May conference of the United Nations' Food and Agriculture Organization in Rome.

Organic agriculture is an environmentally friendly choice, conference presenters said, for reasons including more efficient use of local natural resources and less reliance on fossil fuels (organic farmers don't use petroleum-derived fertilizers or pesticides).

Research by the Rodale Institute and others also show that organic soils retain 20 percent to 40 percent more water, so they require less irrigation and produce better yields than conventional crops during times of drought and climate change.

On the social front, organic agriculture—which requires 30 percent more labor per hectare, or 2.5 acres—offers employment opportunities and contributes to rural development. Health benefits are another important contribution, said experts. Avoiding pesticide use means safer drinking water and better health for farmworkers. Some initial research has also shown that organically grown foods may contain higher levels of micronutrients such as vitamin C. Organic farmers' choices to plant drought-tolerant or locally acclimatized species also help increase overall biodiversity of crops.

According to Nutrition Business Journal, U.S. consumers racked up about $15.7 billion in organic food sales in 2006. By 2010, experts estimate it will climb to $24 billion, comprising about 4 percent of retail food sales.