WASHINGTON — Scientists have unlocked a gene that one day could bring bigger ears of corn, more roses on each bush and even faster-growing forests, all by controlling a hormone inside each plant.
"When I think of the uses--it's fantastic," said Jedrzej Szerszen, a Michigan State University plant pathologist who helped discover how to genetically manipulate plants' natural growth hormone.
In a study published today in the journal Science, Szerszen and colleagues Robert Bandurski and Krzystof Szczyglowski isolated and cloned a gene that controls the hormone.
"It's exciting," said Dr. Jerry Cohen of the U.S. Department of Agriculture, who said genetic engineering might begin replacing growth chemicals in two to five years. "This is the first step."
Plant growth depends on a hormone called IAA. A gene called iaglu produces an enzyme that controls how much IAA is free within plants to boost growth and how much is inactive, explained Bandurski, who has researched IAA for 30 years.
The Michigan State scientists plucked the iaglu gene out of corn, cloned it and manipulated it to produce more of the vital enzyme.
They then injected tobacco, which grows quickly and accepts genetic engineering well, with the gene. Instead of the normally unwieldy plant, they grew bushier tobacco with more branches--essentially getting the same amount in a smaller space.