579 / 2019-04-10 17:10:03

Root hairs enhance seedling survival upon soil disruption

Arabidopsis thaliana,root hair,root adhesion,surface area,seedling's viability

Growth and Development > Growth and Development

Root hairs comprise a great part of the root surface area. Compared with their nutritional function, the physical function of root hairs has been poorly characterized. Our study focused on the physical role of root hairs of the Arabidopsis seedling root in interaction with water and soil and their contribution to the survival of seedling plants upon soil disruption. Five transgenic Arabidopsis lines with different root hair lengths were adopted to assess the physical role of seedling root hairs. Upon soil disruption by water falling, long-haired lines showed much higher survival rates than short lines. The root pulling test revealed that long-haired roots attached more soil than short-haired roots. When seedlings were pulled out and laid on the soil surface for 15 days, the survival rates were higher in the long-haired seedlings than in the short-haired seedlings. Moreover, the water-holding capacity of the root was much greater in long-haired seedlings than in short-haired seedlings. These results suggest that root hairs play a significant role in the survival of seedlings upon soil disruptions which are likely to be fatal to the tiny seedling germinating on the thin soil surface with a short primary root and root hairs as the only anchoring root system.