How does salinity affect root growth? Does it increase or decrease root growth?
Unfortunately, we don’t know all the answers! Salt in the root zone decreases root growth. In some plants we call halophytes (literally salt plants) a little bit of salt seems to improve overall growth, in both roots and shoots (if you measure total biomass, i.e. the weight of the plant material). Examples of this are seen in barley and atriplex. Why this is the case is not known, but it is speculated that these plants require Sodium ion (Na+) or Chloride ion (Cl-) for growth.
