With a recent award of $1.5 million from the National Science Foundation in her tool belt and a catalogue filled with research on plant genomes and evolutionary processes, molecular biologist Maheshi Dassanayake has dedicated her life to answering one big question: How can we continue to feed the world’s growing population?
It’s no secret that traditional farming practices are under attack from environmental changes occurring around the world. In Louisiana alone, hurricanes are whipping salty storm surges into rice, cane sugar, and soybean fields, disrupting three of the state’s largest agricultural productions.
In coastal Koggala, Sri Lanka—about 85 miles south of Colombo, the Sri Lankan capital where Dassanayake grew up—communities are suffering from sand extraction to mangrove clearance to reef destruction, which disrupt resources on which locals are highly dependent.
“You have to remember, there’s no human life without plants,” she said, “and the concern surrounding food security is no longer a question of if or when it will happen because it is happening now.”
Dassanayake, an associate professor in the College of Science’s Department of Biological Sciences, represents a larger population of the world’s researchers, innovators, and deep thinkers who are hunting for original ways to save our food sources. But she didn’t start out hoping to solve the growing problem.
In fact, Dassanayake was more interested in the Sri Lankan rainforest. Having grown up in the suburbs of Colombo, she came into little contact with the wild nature of the tropical environment and what it offered. Her lack of access to nature fueled her fascination for science, plants, and even more specifically, mangroves.
Mangrove forests make up one of the most productive and biologically diverse ecosystems on the plant. Mangroves, themselves, are classified as extremophytes, or plants that can survive in extremely harsh conditions—in this case, prolonged flooding, high temperatures, and hurricane-force winds—and their ability to not only live, but thrive, in their environment is what drew the researcher to study extremophytes, in general. But she found one pesky problem with her field research.
“Leeches are everywhere in the country’s rainforest, and I could not overcome that fear,” she laughed.
As an undergraduate, Dassanayake had planned a five-day trip into the tropical space with students from her class, but just as their trek began, the group was attacked by a recently disturbed beehive.
“We all started running until we could find a stream to jump in,” she recalled. “Leeches don’t just live in the water. Sometimes there are hundreds that form a ball and fall from branches, so I was prepared, had covered head to toe in leech repellant just to be sure, but jumping into the water, it all washed off. You can imagine what happened next.”
Avoiding that particular phobia of hers steered her into another direction: molecular biology. Dassanayake found a sense of alignment between her ongoing interests in plant diversity, especially extremophytes, and her new research field.
“Even now, the more I learn about plants, I realize that there’s so much that we do not know about how plant genes work and how much we could use that to make our agricultural products much better.”
So how do extremophytes play a part in feeding almost 8 billion people?
Extremophytes are unique in their biology, being able to withstand environments so intensely hot, cold, salty, acidic, alkaline, dry, or barren that conventional crops cannot be grown. While we see environmental stressors taking their toll on traditional agricultural plants, extremophytes have the genetic makeup that allow them to go undisturbed.
Dassanayake and her team began by looking at two specific extremophytes: Schrenkiella parvula and Eutrema salsugineum. These two plants represent excellent models for understanding mechanisms of stress tolerance that may not be present in stress-sensitive species, including many of the current rice or soybean cultivars.
S. parvula is native to the Lake Tuz region—a direct translation being “Salt Lake”—, which is located in the arid Anatolian plateau in Turkey. It can thrive in soils that are similar to sea water strength in salinity. Salt stress is one of the most serious environmental stresses limiting crop production, and because of irrigation and climate crisis-driven salinization, there is a global rise in agricultural land lost to soil salinity.
E. salsugineum, or more commonly known as saltwater cresses, also typically grows in salty environments, but this plant is found in the subarctic regions and therefore can additionally withstand the frigid temperatures of the northern U.S., Canada, China, and Russia.
Dassanayake is among a group of LSU researchers studying these plants and building a genomic toolkit that can be used to pull data and answer specific research questions. Once the database has been built, Dassanayake can explore the genetic pathways that make these plants successful in their ability to survive.
And exploring these plants’ genetic makeup will not just be for human consumption. Extremophytes have secondary metabolites that can be used for pesticides, herbicides, and even as bioenergy crops. If industries can create biofuels from these plants, then conventional land used for farming will not need converting.
“Millions of years of evolution have made these extremophytes real champions to survive harsh environments,” Dassanayake said, “and that’s what we need to tap into quickly. We need to be able to pick the genetic elements that we could use in our breeding programs to make our crops grow better.”