Studying circadian rhythms in plant roots

The endogenous circadian system drives ~24 hour oscillations in a diverse range of biological processes. In sessile plants, the circadian system is of particular importance, allowing the plants to adapt to daily changes in their environment. Over the past decades, extensive research has given us an understanding of the mechanism of the circadian system in the aerial parts of the plant. By contrast far less is known about the system in roots even though understanding circadian rhythms in plant roots is important for determining how plant organ systems are organized and coordinated. However, circadian research on roots has been hampered by the lack of a high-throughput, non-invasive and low-cost techniques. Previous work in our lab has shown that thermal imaging can be used to study circadian rhythms aerial plant organs and the aim of this research project is to adapt thermal imaging to allow us to study circadian rhythms in roots. Given their underground location in most plants, roots are a particularly challenging plant organ to image. Using different growth techniques including hydroponics and aeroponics, I show that thermal imaging can be used successfully to image oscillations in roots from different plant species. In further experiments, I am analyzing how root rhythms are affected by mutations in the circadian system as well as the effects of metabolites on root circadian rhythms. The ability to make high temporal resolution measurements in plant roots will allow us to understand how the root circadian system is regulated.