Designing Drought-Resistant Crops

Droughts are a farmer’s worst nightmare: Crops meant for the dinner table wither away in the dry heat leaving people hungry and farmers broke.

Not all plants are as sensitive to drought, though, and it is the genetic makeup of these more resilient plants that is of interest to scientists who feel the need to develop crops that can handle drastic shifts in their environments.

U.S and Finnish researchers recently discovered the specific gene responsible for controlling the amount of water released by the plant as it absorbs carbon dioxide-more specifically, the gene that controls the plant’s stomata.

The stomatic pore in a tomato leaf.
(Photo: Wikipedia)

All leaves are covered with stomata, which are tiny pores used to suck up carbon dioxide and to release water vapor back into the air.

Some of the ‘hardier’ plants close up their stomatal pores when ozone levels increase.

This reaction also reduces the amount of water lost during the harsher seasons. (It is interesting to note that plants suffer from excessive amounts of ozone rather than thriving in a CO2 rich environment when they use this specific gas for growth.)

The gene in question controls when the stomata are open or closed. Unfortunately, with their stomata closed, plants are unable to absorb the excessive amounts of CO2 in our atmosphere.

Up to 95% of water loss occurs through these pores while they are open, so manipulating the genetic makeup of plants to increase their sensitivity to droughts (forcing them to close their stomata) could have a positive effect on their survivability: A little water lasts much longer.

This may slow plant growth since CO2 is a necessary component for photosynthesis and plant development (with the stomatal pores closed, less CO2 makes it into the plants’ system), but a smaller plant is still better than a dead one.

Researchers claim that within the next few years plants could be genetically modified to hold on to the precious water that is so hard to come by during a drought, while still being able to absorb the CO2 they need for photosynthesis.

This is a win-win situation: It will allow crops to survive in arid regions while also sequestering the atmosphere’s CO2.

via Science Daily

Leave a Reply

You must be logged in to post a comment.