New Phytol. http://doi.org/bckt (2016)
Ephemeral roots — short-lived, non-woody roots situated at the edge of the root system — have been observed in temperate tree species, and are thought to play an important role in resource acquisition. But whether they occur more widely has remained unclear.
Bo Liu, of the Xinjiang Institute of Ecology and Geography, China, and colleagues probed for the presence of ephemeral roots in trees, shrubs and herbs common to the southern edge of the Taklamakan Desert. They grew the plants in a series of glass-walled chambers that they had constructed in the region, and monitored the morphology and longevity of the roots over the course of one and a half years. Ephemeral roots were apparent in all species studied.
Unlike perennial woody roots, the ephemeral roots lasted no more than four months, lacked secondary tissue and a continuous cork layer, and contained high concentrations of nitrogen. They were also more metabolically active, having high rates of respiration compared with the longer-lived roots.
The findings suggest that ephemeral roots may be common to perennial plants across a range of functional groups.