Fluorides and its effects on plant metabolism.

Abstract

Fluoride (F) is one of the most important phytotoxic air pollutants (Weinstein, 1977). F toxicity to terrestrial plants has been studied extensively and has been clearly demonstrated in laboratory, greenhouse and controlled field plot experiments (Weinstein, 1977; Doley, 1986, 1989; McCune et al., 1991). F injury to plants may be acute or chronic. Acute F injury is caused by short-term exposures to high concentrations of atmospheric F. Injury symptoms similar to those caused by atmospheric fluorides may also be due to other agents, such as insects, disease, nutritional disorder and adverse weather. F injury to vegetation commonly results from gradual accumulation of F in the plant tissue over a period of time (Davison, 1984). Therefore the duration of exposure as well as the atmospheric concentration is important in determining the severity of injury.