|Photosynthetic performance and pigment content in the aquatic liverwort Riella helicophylla under natural solar irradiance and solar irradiance without ultraviolet light|
Conde-Álvarez, R.M.; Pérez-Rodríguez, E.; Altamirano, M.; Nieto, J.M.; Abdala, R.; Figueroa, F.L.; Flores-Moya, A. (2002). Photosynthetic performance and pigment content in the aquatic liverwort Riella helicophylla under natural solar irradiance and solar irradiance without ultraviolet light. Aquat. Bot. 73(1): 47-61
In: Aquatic Botany. Elsevier Science: Tokyo; Oxford; New York; London; Amsterdam. ISSN 0304-3770, more
Fluorescence; Oxygen; Photosynthesis; Pigments; Solar radiation; Ultraviolet radiation; Riella helicophylla
|Authors|| || Top |
- Conde-Álvarez, R.M.
- Pérez-Rodríguez, E.
- Altamirano, M.
- Nieto, J.M.
- Abdala, R.
- Figueroa, F.L.
- Flores-Moya, A.
The effects of solar radiation and solar radiation deprived of ultraviolet radiation (lamda<395nm) on photosynthetic performance and pigment content of the aquatic liverwort Riella helicophylla (Bory et Mont.) Mont. was investigated throughout a natural daily-light cycle, from sunrise to sunset. Photosynthetic performance was estimated by means of pulse amplitude-modulated (PAM) fluorescence and oxygen production. Photosynthetic characteristics changed daily and between the two solar radiation conditions. The lowest values of optimal quantum yield (phiPS II) took place at noon (70 and 55% lower than early in the morning under UV- and non UV-screened plants, respectively), in agreement with the highest amounts of solar radiation. However, at this time, the electron transport rate (ETR) achieved the highest values of the day (63 and 125µmol -1m-2s-1under PAR+UVA+UVB and PAR treatments, respectively). Significant differences (P<0.05) in Fv/Fm, ETR, initial slope of ETR versus irradiance curve, photosynthetic capacity, chlorophyll a and phenolic compounds were found between the two radiation conditions, especially at noon. Recovery of inhibited photosynthesis took place in the afternoon, so the current ultraviolet radiation does not seem to cause, irreversible damage to the photosynthetic apparatus of R. helicophylla in the short term.