Groundbreaking Images of Root Chemicals Reveal New Insights on Plant Growth

Researchers from the University of California San Diego and Stanford University have provided insights into a new understanding of essential root chemicals that are responsible for plant growth. Using a mass spectrometer, the researchers produced a “roadmap” that shows the distribution of small molecules along stem cells of maize plant roots and how their placement factors into the plant's maturation.

As a visiting scientist at Stanford University, Assistant Professor Alexandra Dickinson collaborated with Sarah Noll and Professor Richard Zare who developed a mass spectrometry imaging system that helps surgeons distinguish between cancerous and benign tissue during tumor-removal operations. Dickinson, Zare, and Noll adapted the technology called “desorption electrospray ionization mass spectrometry imaging” (DESI-MSI) to probe plant roots for the chemicals involved in growth and energy production. The team initially focused on maize plants at the root tips, where stem cells play an active role in the plant's development. Zare said that to understand plant roots from the biology side, they needed to find out which chemicals are present.

The team then produced images, believed to be some of the first to reveal the transition between stem cells and mature root tissue. The images show the foundational role of metabolites—molecules involved in the plant's energy production. Tricarboxylic acid (TCA) cycle metabolites became the focus of the research since they were found to be a key player in controlling root development. Also seen in the new images were previously unidentified compounds that could be critical for plant growth.

For more details, read the article in UC San Diego Today.