Grow! That's Nature's prime directive to living things, and one that genetic engineers have harnessed for making powerful drugs such as human growth hormone. This time, University of Edinburgh scientist Peter Doerner has used genetic engineering to create plants that just plain grow faster and bigger-up to three times as big, in fact.

In 1996, Doerner discovered that a gene called cyc-1 helps control the rate at which plant cells divide. Now he has created a strain of Arabidopsis thaliana, a flowering mustard plant, with an extra copy of this gene that kicks in at just the right moment in the cell-division process. The payoff will come in crops like rice, which could reach maturity faster with the new gene inserted, enabling farmers to squeeze in an extra harvest.