Plant Geneticist Identifies Drought-Tolerant Gene

These possibilities are a step closer, thanks to a U of T professor's isolation of the gene that controls drought tolerance in plants. Botanist Peter McCourt has discovered a method involving gene suppression that will enable a plant's leaves to stay green long after the last watering. "Drought is obviously a problem for farmers worldwide; these genetically engineered plants will be able to wait out periods of drought without dying." In October, he co-authored a paper in the journal Science outlining his discovery.

The plant hormone abscisic acid triggers the closure of the plant's stomata -- minute pores located on the leaf -- in times of stress. McCourt has discovered abscisic acid is controlled by the ERA1 gene and that by inhibiting the gene's action, a plant becomes super-sensitive to drought. By suppressing the gene -- and thereby keeping the stomata closed -- he found it is possible to control water loss so plants last longer despite the onset of adverse conditions.

While shutting down the action of the gene inhibits growth and thereby would lower crop yields, McCourt believes farmers facing drought would prefer retaining at least a portion of their crop as opposed to losing everything. He remains confident that further research will find a way to inhibit the action of the gene only when drought is anticipated.

The initial results of McCourt's research may be useful in applications such as the cut flower industry. He has licensed his discovery to Kingston-based Performance Plants, a small biotechnology company working on a drought-tolerant strain of canola, one of Canada's leading export crops.