Emerging trend: Teaching plants to grow big

We’ll need more crops to feed the two billion more people who will join us over the next 30 years. But those people will take up a lot of the land we’ll need to grow the food to feed them.

Also troubling: fertilizing and cross-breeding have hit their limits, adding no more than 2 percent annual increases in yield.

The solution: grow bigger plants – not by cross-breeding or using more fertilizer but by tweaking their genes to improve photosynthesis, the basic process by which plants turn sunlight and carbon dioxide into food for themselves and for us.

Photosynthesis could use some improvement; only a bit of the sunlight that plants absorb is used to make the sugars and carbohydrates that fuel life. The reason: in addition to processing carbon dioxide, plants latch onto oxygen as well, which is potentially toxic to them. So they have to go through an elaborate biochemical process to neutralize that toxin. That extra work can reduce a plant’s crop yield by as much as half of what it otherwise might be.

Various scientists have engineered a suite of new genes that created a shortcut for disposing of the oxygen and tested it in tobacco plants. The altered plants averaged almost 25 percent more size than their unassisted siblings.

Other scientists have genetically engineered tobacco plants to make more efficient use of sunlight, resulting in about a 15 percent increase in productivity.

The researchers are now combining the new gene packages into the same tobacco plants and also moving them into food crops such as soy and potatoes.


Genetically modified organisms have gained a bad rap, in part because some of these Frankenplants contain alien genes from bacteria, viruses, or other foreigners to help them resist herbicides or spontaneously produce their own insect poisons.

But genetic modifications that increase plant yields by boosting plants’ own natural processes hold no obvious risks to human health. Fooling with Mother Nature gives rise to reasonable fears, but this kind of gene-tweaking in food crops will become as normal as grafting or cross-breeding has been for decades.

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