Tomatoes yield thicker ketchup.

• Position: Tomato genetic engineering

Purdue University is reaping new fruits of its plant genetics research, harvesting tomatoes that should yield thicker sauce, ketchup, or paste with less processing. The researchers expect the tomatoes rolling in from their Indiana farm plots, like those grown earlier in Purdue greenhouses, to show a 10% increase in soluble solids. "That would give you 10% more ketchup from the same number of tomatoes," points out professor of horticulture Avtar Handa.

Other researchers have genetically altered ripening in tomatoes, but Handa and graduate student Denise Tieman are the first to use a gene that increases soluble solids in the fruits. Because they have altered only ore gene in the test tomatoes, the fruits grow and ripen like traditional varieties.

Breeders usually take years to do the same thing. After finding a wild tomato that carried the gene they wanted, they would cross a commercial variety with that wild plant. Years of further crosses would follow. "Traditional cross-breeding with wild species also transfers bad characteristics," Handa notes. "It takes a long time to get rid of the traits you don't like." With genetic engineering, it is...