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Photoprotection of PSII in Hawaiian lobeliads from diverse light environments.
- Source :
-
Functional Plant Biology . Jul2008, Vol. 35 Issue 7, p595-605. 11p. - Publication Year :
- 2008
-
Abstract
- Excess irradiance can reduce the quantum yield of photosynthesis via photoprotective energy dissipation, inactivation or downregulation of PSII. We examined variation in photoprotection as part of a study of adaptive radiation in photosynthetic light responses by Hawaiian lobeliads. We measured the maximum efficiency of PSII (Fv/Fm) and recovery of Fv/Fm after high light stress in field populations of 11 lobeliad species and in four species growing under common-garden greenhouse conditions. Species showed no difference in Fv/Fm (0.82 ± 0.02 (mean ± s.e.)) or in their ability to recover from light stress under field conditions. Average recovery was 74 ± 1.4% within 1 h of removal of the stress suggesting that all species maintain the ability to recover from high light stress, at least in the short-term. In contrast, the results from the common-garden indicate that long-term exposure to high irradiance and associated higher temperatures can cause a sustained reduction in PSII function. Species showed decreased Fv/Fm and percentage recovery as treatment irradiance increased. Fv/Fm and percentage recovery were positively related to native habitat PFD across species, suggesting that there has been a diversification in high light tolerance, with species from sunnier environments better able to avoid sustained declines in PSII function. [ABSTRACT FROM AUTHOR]
Details
- Language :
- English
- ISSN :
- 14454408
- Volume :
- 35
- Issue :
- 7
- Database :
- Academic Search Index
- Journal :
- Functional Plant Biology
- Publication Type :
- Academic Journal
- Accession number :
- 47730287
- Full Text :
- https://doi.org/10.1071/FP08031