Effects of fluoride on chlorophyll a fluorescence in spinach

• Published in: Environmental pollution (1987) Vol. 89; no. 2; pp. 203 - 208
• Main Authors: Boese, S.R., MacLean, D.C., El-Mogazi, D.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 1995; Elsevier
• Subjects: abiotic stress; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; chlorophyll; concentration; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on plants and fungi; fluorescence; fluorides; Fundamental and applied biological sciences. Psychology; hydrofluoric acid; monitoring; petioles; photosynthesis; pollution; sodium fluoride; Spinacia oleracea; Phytotoxicity; Dicotyledones; Angiospermae; Hydrofluoric acid; Fluorescence; Spermatophyta; Concentration; Method; Spinacia oleracea; Chenopodiaceae; Chlorophyll a
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/0269-7491(94)00052-F

Chlorophyll a (chl a) fluorescence was used to determine the effects of treatments with gaseous HF or aqueous solutions of NaF on the photosynthetic apparatus of spinach prior to the appearance of visible injury. Placing the petioles in 2 m m NaF for 3 h resulted in the accumulation of 240 ppm F in leaf blades. The second oldest leaves of spinach plants accumulated similar concentrations (270 ppm F) when the plants were exposed to gaseous HF at 5 μg F m −3 for 6 days. These NaF and HF treatments did not result in visible injury nor did they affect F o , F m or F v F m . However, during the slow (>2 s) induction kinetics, fluorescence quenching in fluoride-treated leaves increased during the P to S phase and the M peak was no longer resolved. This was due, in part, to increased photochemical quenching. The results are consistent with a reduced ability to develop or maintain a trans-thylakoid proton gradient in chloroplasts containing elevated concentrations of F.