Texas Tech University

The Future of Fiber

By: Kaitlyn Hale 

Texas Tech researchers are developing genetically modified cotton that can thrive high heat and low water conditions.

cotton plant ready for harvest in a field
Transgenic, or genetically modified, cotton could potentially yield the same amount of fiber as nontransgenic cotton while using less water and in higher temperatures. Some types could even tolerate salty soil or water.

Thunder booms. Electricity flies from machines to the body in the center of the room. The monster rises and Frankenstein shouts, “It's alive!” All too soon, the creature becomes something not even his creator can control.

It's a frightening scene depicting science gone awry, which may be the reason why critics were quick to coin the term Frankenfoods when describing genetically modified, or transgenic, organisms.

However, as fresh water becomes an increasingly scarce resource and droughts spread across the country, researchers at Texas Tech are exploring the safe process of creating genetically modified cotton that can withstand heat, drought and high levels of salt in water or soil.

“I like to present the facts to people because they don't have to be scared of GMOs,” said Hong Zhang, a professor of plant molecular biology and plant biotechnology at Texas Tech. “It's been very thoroughly studied, and before we put that in a field we have to study it extensively to make sure that it poses no threat to human health and to the environment.”

Zhang has spent his career researching genetics. Currently, he and his doctoral students are working to see which genes, or combination of genes, create a plant that produces higher yields with less resources.

“What we are doing today,” Zhang said, “is preparing our crops for much harsher environmental conditions tomorrow: less water for irrigation, higher atmospheric temperatures, and saline soils in many places. I believe that our research will have a positive impact on agriculture in the future.”

Planning for the Future

rows of cotton plants in a greenhouse
Transgenic and wild type cotton are grown side by side in a greenhouse where environmental conditions can be more easily controlled.

The process to create a transgenic plant ready for commercialization takes more than five years to complete. So it's important that researchers are looking for solutions to future problems right now.

Once a researcher identifies the gene they want to express in a different plant, they have to create the transgenic plant. Often, researchers start their experiments in an Arabidopsis plant.

“We call Arabidopsis kind of the fruit fly of the plant world,” Jennifer R. Smith, a doctoral candidate who works with Zhang, and the greenhouse manager for the Department of Biological Sciences.

Arabidopsis has faster generations, so the plant's entire lifecycle is completed in about six to eight weeks. It's much faster than cotton, which is more like six months, Smith said. The smaller scale experiments with Arabidopsis give researchers a chance to determine if the gene they want to express is likely to work in other plants.

Once researchers identify the genes they want to use, it takes about two years to develop the transgenic cotton plant. After the transgenic cotton plant is developed, it's tested in the lab to determine if the new gene is working as expected in the plant.

Eventually, the transgenic plants are tested under controlled conditions in the biology department's greenhouse. If all goes well there, new plants are planted in a field to track the plants' growth in the kind of environment they'll be grown in for agricultural production.

smaller, wild type cotton plants next to more healthy transgenic cotton plants
Under reduced irrigation conditions for 70 days, transgenic cotton plants (three plants on the right) were taller and produced more flowers than wild-type cotton plants.

Every step of the way, the transgenic plants are grown beside wild type, or non-genetically modified, cotton. The wild type plants act as the control group to determine how the transgenic plants perform.

Nardana Esmaeili, a doctoral candidate who works with Zhang, is currently harvesting cotton from her first test, which grew in a United States Department of Agriculture field in Lubbock this summer. She'll have to repeat the test next year, perhaps on a larger scale.

“In the field of plant research,” Esmaeili said, “we need to grow plants at least two or three seasons and monitor their performance over the period of time and make sure that the performance and response of transgenic plants to stress conditions are consistent. This is what we usually do in biology, and we have replicas for each individual experiment.”

Right now, Smith is in the process of testing another cotton variety that uses a gene from the creosote bush, a desert plant.

wild type cotton with smaller root systems than transgenic cotton
At the end of the reduced irrigation treatment, transgenic cotton plants (three plants on the right) produced bigger biomass and more fibers than wild-type cotton plants.

“I'm not finished testing mine,” Smith said, “I hope it's going to be a high-yield plant under multiple stress conditions. In the field, you don't just see drought or you don't just see heat. You see it in combination, so our goal here is really to create plants with multiple stress tolerances.”

The optimal temperature for growing cotton is about 82 degrees, Zhang said. Regions where cotton is grown, like the South Plains of Texas, can easily reach into the high 90s during the summer, which stresses the plant and results in lower yields for farmers.

“Wild type cotton will suffer under high-temperature conditions,” Zhang said, “but our transgenic plants behave just like under optimal conditions. They continue to grow, continue to photosynthesize and are much more heat resistant.”

Two is Better Than One

Transgenic crops that express a single new gene have been on the market since 1982. Since then, researchers have inserted different genes into a variety of crops, including cotton, corn and soybeans.

“However, in our lab, we are trying to insert multiple genes into crops, specifically cotton, to make them more resistant to multiple stresses,” Esmaeili said.

The concept of adding multiple genes into a single plant is fairly new, and Emaeili said Zhang's lab is one of the pioneers in this new aspect of the field.

“If one gene is tolerant to one stress,” Smith said, “what if we added two genes that could help with three stresses? That was kind of our idea.”

Maheshika Herath, a doctoral student who works with Zhang, is currently focusing on two genes that will ideally make cotton more drought and salt tolerant and better at absorbing fertilizer.

Though some salt is needed for healthy plant growth and development, high concentrations can be toxic. Herath said several factors can contribute to high salinity levels in soil, including over usage of fertilizer, inefficient drainage systems on irrigated land, and usage of brackish water for irrigation. Soil with high salinity levels either can't be used to grow crops or has to go through costly management practices to be fertile again.

Currently, about 20% of total agricultural land is affected by high salinity, Herath said, and that number is projected to increase to 50% by the year 2050. Transgenic plants could potentially allow that unusable land to be planted without the additional costs to desalinize it.

Hong Zhang was named a 2016 Integrated Scholar by the Office of the Provost. Integrated Scholars are faculty who dedicate themselves to a course of lifelong learning and advance Texas Tech's role in educating, serving and inspiring others to do the same.

Salt tolerant plants could also mean an alternative water source for agriculturalists.

“We're running out of water,” Smith said, “and when you start to run out of water it also diminishes the water quality. So when aquifers start drying up, the water becomes a little more salty. So we need to work on that now.”

Fresh water is not an infinite resource, and a large portion of it currently goes to agricultural production. Salt tolerant plants mean more water for animal production and people.

“Ideally, our long-term goal is to make crops that can tolerate ocean water,” Zhang said. “Then we don't have any salinity issues. That day will come. Eventually, we'll be able to make crops that tolerate ocean water. That day will come hopefully within our life time.”

As arable land shrinks and the population grows, the ability to increase production of food and fiber becomes an increasingly important concern.

“We need to increase agricultural production by 70% to 100% in order to meet the demands of increasing population,” Herath said. “But, nowadays the production capacity has come to its limits and there is no way to increase production by several folds just by using fertilizers or using other management practices.”

Esmaeili said she can understand why people are concerned about the way their food is produced, but the science behind transgenic plants is sound.

“Actually, the chance of any unplanned and unintended changes in transgenic plants made through genetically modified techniques are very, very low,” Esmaeili said. “DNA transfer occurs naturally, and several natural mechanisms allow this DNA flow in the environment. The genes that we use are not artificial, and you can find them out there in other plants.”