Article by Hillary Hoffman | Photo and video courtesy of Chelsea Davis
UD mechanical engineers collaborate with Purdue researchers to understand how plant cells stay connected as leaves develop
The sizes and shapes of leaves help determine how plants grow and function. Researchers are working to understand how strong mechanical forces in leaves enable growth while maintaining physical connections between individual cells. This knowledge could aid future plant breeding and biotechnology approaches to produce more resilient crops.
Chelsea Davis, associate professor of mechanical engineering at the University of Delaware, is collaborating with Purdue University researchers Daniel Szymanski and Thomas Siegmund to study plant cell adhesion. The project is funded by the National Science Foundation, with a $345,000 award to UD and a $1.1 million award to Purdue.
Davis’ lab uses specialized tools to measure the mechanical strength of plant tissues at extremely small scales. Her team grows Arabidopsis thaliana seedlings sent by Szymanski, a professor of botany and plant pathology, until they reach the cotyledon stage, a sprout with two small leaves measuring just millimeters across. Using micromechanical grips under a microscope, the team pulls the leaves apart to measure how much force it takes to separate the cells and how the tissue fails.
“We were able to measure how hard it was to pull apart and how far we had to stretch it before it pulled apart. We also watched how it separated,” Davis said.
These experiments generate quantitative data on the strength and toughness of cell-to-cell adhesion. The data can be compared with computational mechanical models generated by Siegmund and his team, helping refine the models and improve their accuracy in predicting “hotspots” where stress occurs in leaf tissue.
Davis said the project attracts graduate students interested in applying engineering tools to biological problems. One postdoctoral researcher involved in the work now works for the company that builds the measurement tools used in her lab and is helping expand their offerings.
“Because former postdoc Michael Wilson can speak like a plant biologist now and has seen how you can apply mechanical deformation to this whole new field, he’s going to change their business model,” Davis said. “It opens up a whole other category of customers to them, and it potentially brings some tools to the botany community that they didn’t have before.”
