Imagine if cultivated crops were watered as infrequently as forgotten houseplants.
While many wild plants have adapted to survive drought, most cultivated crops tend to be vulnerable to these natural occurrences. In 2023, the United States experienced significant crop losses, with Texas alone reporting $4.8 billion in damages, of which nearly 80% were attributed to drought, according to the American Farm Bureau Federation. To prevent losses of crops to drought and other seasonal hardships, researchers from Budapest, Hungary, and the Department of Energy's Oak Ridge National Laboratory are studying a plant known for its remarkable ability to endure periods of little to no rain.
Ctenanthe setosa, also known as the Never Never plant, can survive up to 60 days without water and recover once rehydrated, making it the perfect candidate for this study conducted in part at ORNL. The team used small-angle neutron scattering to study how the Never Never plant can withstand water withdrawal, and their findings , published in Physiologia Plantarum, offer insights into how studying these resilient plants could improve cultivated crops' resistance to drought-related stress.
"We quickly realized our research would greatly benefit from using neutrons," said Renáta Ünnep, a researcher from the HUN-REN Centre for Energy Research in Budapest. "Our experiment involved measuring the plant's water deficiency over a long period, and neutrons serve as a nondestructive option to observe the nanoscale structure of the photosynthetic membranes in these plants."
Without water, plants lose their ability to properly photosynthesize, which can hamper growth and reduce crop yield. Beyond its ability to survive a drought, the Never Never plant possesses a subsequent recovery mechanism that the team studied using the Extended Q-Range Small-Angle Neutron Scattering Diffractometer ( EQ-SANS ), located at ORNL's Spallation Neutron Source (SNS).
The SNS offers unprecedented research opportunities due to its intensely bright neutrons and world-class instruments. EQ-SANS is one of 19 instruments available at SNS for users such as Ünnep and Katalin Solymosi, a plant biologist at the Department of Plant Anatomy, Eötvös Loránd University in Budapest.
"This was the first time that fully intact plants under drought-related stress conditions and the recovery process were observed minute by minute," said Solymosi. "Neutrons allowed us to chart nanoscale-level changes in the structure of the plants' photosynthetic membranes over the course of the drought period as well as carefully observe how they revived following rehydration."
Along with neutrons, the team used methods such as light microscopy and transmission electron microscopy to study the plants, but these other methods do not permit examining the same piece of leaf multiple times without damaging the sample. Therefore, the nondestructive nature of neutrons was imperative to the integrity of the experiment.
Gergely Nagy, a neutron scattering scientist at ORNL, understands the importance of neutrons in a study involving a task as delicate as keeping a houseplant alive in such extreme conditions. "Neutrons kept us from disrupting the samples," said Nagy. "Other methods also pose the risk of disturbing the fully native state of the plants, especially their water content during sample preparation. To take the potted plant to EQ-SANS and observe parts of it in completely natural conditions is something only neutrons can do."
Along with studying the effects of drought stress, Nagy expressed interest in exploring SANS' potential in aiding similar studies; he's optimistic about what the future holds. "With every experiment performed at EQ-SANS, we are improving our abilities to adapt the instrument to different types of research. The collaboration between myself, Ünnep and Solymosi doesn't end here, meaning both the science case and the instrument's capabilities to study photosynthetic systems will continue to advance."
SNS is a DOE Office of Science user facility at ORNL.
UT-Battelle manages ORNL for DOE's Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, visit energy.gov/science . - Kaeli Dickert and Paul Boisvert