A nuclear mutant ofArabidopsis thalianaselected for enhanced sensitivity to light-chill stress is altered in PSII electron transport activity
| Autor: | Luisa Carraro, Alberto Vianelli, Delia Tarantino, Carlo Soave |
|---|---|
| Rok vydání: | 1999 |
| Předmět: |
education.field_of_study
Photoinhibition biology Photosystem II Physiology Population Mutant food and beverages Cell Biology Plant Science General Medicine biology.organism_classification Photosynthesis chemistry.chemical_compound chemistry Chlorophyll Photoprotection Botany Genetics Biophysics Arabidopsis thaliana education |
| Zdroj: | Physiologia Plantarum. 107:361-371 |
| ISSN: | 0031-9317 |
| DOI: | 10.1034/j.1399-3054.1999.100314.x |
| Popis: | Chilling in the light imposes a considerable level of stress on the photosynthetic apparatus, resulting in a decrease of photosystem II activity and the quenching of maximum and variable fluorescence. We selected in a fah-1 mutagenized population of Arabidopsis thaliana, which permits a direct visible evaluation of the intensity of chlorophyll (Chl) fluorescence, a monogenic recessive nuclear mutant hypersensitive to photoinhibition induced by light and cold. The major phenotypic trait of the mutant is the appearance of chlorotic areas on developed leaves. Photochemical analyses indicate that the mutant is hypersensitive to photoinhibition in excess light in the cold but also at room temperature. The susceptibility to photoinhibition is a consequence of perturbations in photochemistry already present in unstressed plants. Such perturbations result in a greater fraction of the primary acceptor Q A remaining in the reduced state even at low light fluxes. From estimates of the number of total and functional PSII units and measurements of PSII quantum yield and Q A - reoxidation kinetics, the basic lesion of the mutant seems restricted to PSII photochemistry likely affecting the rate of electron transport from Q A - to Q B . |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text