Abscisic acid confers salinity tolerance in Chlamydomonas reinhardtii at
different stages of its life cycle
The effect of abscisic acid (ABA) to increase the osmotolerance of the
freshwater microalga Chlamydomonas reinhardtii at its different stages
of life cycle was investigated. Exogenously added ABA enhanced the
growth and photosynthesis of C. reinhardtii during the vegetative stage.
The hormone also increased the tolerance of this alga to oxidative
stress during gamete formation under nutrient depletion and high
salinity, as it supported their survival for a longer period. We show
that the level of reactive oxygen species (ROS) generated in the
ABA-treated cells was significantly less than that in the untreated
cells under inhibiting NaCl concentrations. Cell size examination showed
that ABA prevents cells from forming palmella when exposed to high
salinity. All together, these results suggest that ABA increases the
tolerance of C. reinhardtii to salt stress conditions.