Differential photosynthetic responses in Riccia gangetica under heat, cold, salinity, submergence, and UV-B stresses

Abstract

Chlorophyll fluorescence transients are recognized as one of the most efficient methods for assessing plant photosynthetic efficiency under stressful conditions. The focus of this research was to investigate R. gangetica's photosynthetic performance under several abiotic stressors, including cold, heat, flooding, salinity, and UV. Chlorophyll (chl), proline, malondialdehyde (MDA) contents, specific energy fluxes (per QA-reducing PSII reaction center) such as ABS/RC, TR0/RC, ET0/RC, DI0/RC, phenomenological fluxes, (ABS/CSm, TR/CSm, ETo/CSm), quantum yields (ɸPo, ɸEo, ɸDo), and performance indices (PIcs and PIabs) were analyzed. Chl content, Fm, Fv/Fm, and PIcs were recognized as highly sensitive parameters to all abiotic stresses. The results of the present study clearly show that R. gangetica has distinct biochemical and physiological strategies for dealing with the negative effects of various abiotic stressors. On the basis of present investigations, tolerance potential against several abiotic stimuli in R. gangetica can be ranked as follows Sl, UV, Ht, Fd, and Cd.

Keywords

• Heat stress
• Submergence stress
• Cold stress
• Salinity stress
• UV-B
• R. gangetica