The sustainability theme will continue in the "Choices for Energy and Construction Crops" station, which focuses on novel uses for plants. One way to reduce the world's carbon
dioxide emissions is to replace coal and oil—Saudi Arabia is the world's largest producer of the latter—with biofuels. One promising alternative the station will highlight is Jatropha curcas, a fruit tree native to Mexico and Central America that also grows in Asia and Africa. Biofuel made from jatropha seeds can be burned in most unmodified diesel engines. With their 40 percent oil content, jatropha's seeds boast high yields of fuel: 2,226 gallons of oil per acre of crop, compared to corn's 230 gallons of ethanol per acre. And, because the tree grows in dry, worn-out soil, it doesn't compete with food crops.