Changing photosynthesis during drought can increase plant resilience

MSU researcher uses gene to control water loss during drought conditions leading to crops that are more resilient.

Drought is one of the top natural disasters affecting regional economies around the world, especially in the agricultural sector. From 2005-2015, drought caused 30% of agricultural production loss in developing countries, amounting to $29 billion, according to a report from the Food and Agriculture Organization of the United Nations.

Kyung-Hwan-Han
MSU researcher Kyung-Hwan Han has a background in forestry and horticulture.

MSU researcher Kyung-Hwan Han is at the forefront of advances in plant gene discovery and biotechnology to help increase crop resiliency in dry weather conditions and support farmers’ crop production.

“Drought is a major limiting factor in crop production that prevents realization of optimum yields worldwide,” said Han, professor in the departments of Horticulture and Forestry. “Development of drought-tolerant crops through biotechnology is both economically and environmentally important.”

Han’s research focuses on the biotechnological improvement of drought tolerance in plants, the molecular mechanisms of wood formation and wall biosynthesis. His background in both forestry and horticulture helps with his research on plant genomics and biotechnology.

“Climate change will make food production more challenging. More frequent and intense droughts are expected with increased global temperatures, which will increase water scarcity and make the cultivation of this vital crop ever more difficult,” Han said. “Drought is an extremely serious and recurring problem that limits crop productivity. As a scientist, my role is to understand how a plant responds to environmental changes.”

Han identified and patented the gene XERICO that can be used to expand drought-tolerant traits in crops. Overexpression of the XERICO gene in transgenic plants stimulates stomatal closure, minimizing water loss at times of drought. Stomata are small pores on the leaves that release water, in this case, in a process called evaporative transpiration.

“This mode of action makes XERICO technology unique and advantageous over other drought tolerance technologies that rely on production of additional metabolites or expression of bacterial DNA,” Han said.

This drought tolerance mechanism can be employed in a highly specific manner. By expressing XERICO only under drought conditions, the technology allows the plant stomata to remain open under normal growth conditions protecting plants from drought stress while also not disturbing normal growth.

While drought resistance has been difficult to effectively engineer in plants, Han’s gene technology has proven successful. Han has also been collaborating on XERICO gene research in corn with Maninder Singh and Addie Thompson from the Department of Plant, Soil and Microbial Sciences (PSM) and on potatoes with David Douches, also from PSM.

XERICO technology has been shown very effective in countering drought stress in multiple crops,” Han said. “With drought being a global issue, commercial deployment of XERICO technology will significantly improve the profitability of growers and enable crop production on arid lands.”

This article was published in Futures, a magazine produced twice per year by Michigan State University AgBioResearch. To view past issues of Futures, visit www.futuresmagazine.msu.edu. For more information, email Holly Whetstone, editor, at whetst11@msu.edu or call 517-355-0123.

Did you find this article useful?


Other Articles from this Publication