Gene Helps Plants Use Less Water Without Reducing Biomass

Scientists at Purdue University discovered a genetic mutation in plants that would enable survival in drought without reduction in biomass. Stomata are structures on the leaves and stems of plants for the entry of carbon dioxide and exit of water vapor during transpiration. During drought, the stomata close to reduce water loss but this also affects carbon dioxide intake, leading to disrupted photosynthesis and growth.

"The plant can only fix so much carbon dioxide. The fewer stomata still allow for the same amount of carbon dioxide intake as a wild type while conserving water," said Purdue scientist Mike Mickelbart. "This shows there is potential to reduce transpiration without a yield penalty."

The researchers found out that mutation of GTL1 gene in Arabidopsis caused reduction in the number of stomata so there is 20 percent reduction in transpiration but carbon dioxide intake remains the same. The biomass of these mutated plants is just the same with that of wild type plants. Due to genetic mutation, GTL1 stops working but SDD1, another gene that controls the stomata, becomes overexpressed resulting to production of lesser number of stomata.

For more details, visit http://www.purdue.edu/newsroom/research/2011/110111MickelbartGene.html.