Comparative effects of osmotic and ionic stresses on yield and biomass accumulation in IR64 rice variety uri icon

abstract

  • In the present study, the comparative effects of osmotic and ionic stresses on rice growth and yield were investigated. The treatments consisted of 3-level combinations of osmotic stress and times: medium (-0.25 MPa), and high stress (-0.52 MPa), applied at the vegetative stage (7-21 d after transplanting, DAT) and reproductive stage (35-63 DAT, starting when the rice plant reached panicle initiation). NaCl and polyethylene glycol (PEG) were used as sources of osmotic stress. Both sources applied at the vegetative and reproductive stages delayed flowering, maturity and reduced the total biomass compared with the control. Na+ concentration in the plant increased with NaCl addition but not with PEG, indicating that the plants were also subjected to ionic stress besides osmotic stress. There was no significant difference in biomass accumulation and yield between the PEG- and NaCl-treatments, indicating that the salinity effect was mainly due to osmotic stress.

publication date

  • 2004
  • 2004
  • 2004