Brace roots are a type of aerial root, which means they are developing in the absence of soil cues (e.g. water, nutrients, mechanical). To understand what environmental cues impact the initiation and emergence of brace roots, we are interested in two environmental cues: Light and Gravity.
We are working to understand the impact of light quality and intensity on root development. A previous study has shown that higher density planting, which results in shading, leads to a reduction of the number of whorls from which brace roots emerge and the number of roots per whorl (Demotes-Mainard and Pellerin, 1992). Thus, we are pursuing questions about how the perception of shade impacts the development of brace roots. Beyond brace roots, we know very little about how roots are impacted by the perception of light. Thus, we are collaborating with Dr. Ullas Pedmale at Cold Spring Harbor Laboratory to also understand these processes in Arabidopsis thaliana and tomato.
To understand the role of gravity in root development, we are pursuing two different tracks. In one series of experiments, we are investigating the response of brace roots to lodging (change in gravity vector). It is known that brace roots will develop along stem nodes closest to the soil surface after lodging, but the process has not been well studied. To further understand how gravity impacts the development and function of mature root systems, we have constructed a large-scale 2D-clinostat to randomize gravity in mature plants. We are collaborating with Dr. Anjali Iyer-Pascuzzi at Purdue University to leverage this platform to understand plant defense responses under simulated microgravity.
Funding: The National Science Foundation Award #1755355 (PI: Pedmale; Co-PI: Sparks); National Aeronautics and Space Administration (PI: Iyer-Pascuzzi; Co-PI: Sparks).
Prior Support: NASA RID Seed Grant (PI: Sparks)