Abstract
Abstract Bearing ‘Valencia’ orange trees growing in a commercial orchard adjacent to a known source of fluoride air pollution were sprayed periodically over a 3-year period with Ca(OH) 2 and CaCl 2 sprays. These materials in spray and dust forms have been used successfully in the Pacific Northwest to protect gladiolus and peaches from the harmful effects of fluoride-containing atmospheres. It has been postulated that calcium reacts with fluoride gases to produce insoluble and therefore nontoxic CaF 2 . Results of these studies indicated that under conditions of high fluoride air pollution, application of lime sprays may improve citrus fruit production, but the mechanism of protection or improvement was not as simple as previously postulated. Immediately adjacent to the source where fluoride air pollution was at a maximum, applications of both Ca(OH) 2 and CaCl 2 were associated with increased internal fluoride accumulation by ‘Valencia’ orange foliage. With increased distance and therefore diminishing air pollution, an apparent reversal in effect was observed with the calcium sprays resulting in reduced internal accumulation of fluoride. Although the effects of CaCl 2 sprays on fluoride accumulation closely paralleled those obtained with Ca(OH) 2 , fruit production was not improved where CaCl 2 sprays were applied, possibly as a result of induced chloride toxicity.
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Claims 6
Claim · model-written summary
Near the fluoride source, calcium sprays were associated with increased internal fluoride accumulation in orange foliage.
Verbatim
e1“Immediately adjacent to the source where fluoride air pollution was at a maximum, applications of both Ca(OH) 2 and CaCl 2 were associated with increased internal fluoride accumulation”
e2“orange trees growing in a commercial orchard”
Claim · model-written summary
With increasing distance from the fluoride source, calcium sprays reduced internal fluoride accumulation in orange trees.
- Taxon
- orange treese2
- Treatment
- calcium sprayse1
- Outcome
- internal accumulation of fluoridee1
- Direction
- reducede1
- Qualifier
- With increased distance and therefore diminishing air pollutione1
Not reportedComparator
Verbatim
e1“With increased distance and therefore diminishing air pollution, an apparent reversal in effect was observed with the calcium sprays resulting in reduced internal accumulation of fluoride”
e2“orange trees growing in a commercial orchard”
Claim · model-written summary
Effects of CaCl 2 sprays on fluoride accumulation closely paralleled those of Ca(OH) 2 sprays.
Verbatim
e1“Although the effects of CaCl 2 sprays on fluoride accumulation closely paralleled those obtained with Ca(OH) 2”
e2“orange trees growing in a commercial orchard”
Claim · model-written summary
CaCl 2 sprays did not improve citrus fruit production.
Not reportedComparator
Verbatim
e1“fruit production was not improved where CaCl 2 sprays were applied”
e2“orange trees growing in a commercial orchard”
Claim · model-written summary
CaCl 2 sprays possibly did not improve fruit production through induced chloride toxicity.
Verbatim
e1“fruit production was not improved where CaCl 2 sprays were applied, possibly as a result of induced chloride toxicity”
e2“orange trees growing in a commercial orchard”
Claim · model-written summary
Under high fluoride air pollution, lime sprays may improve citrus fruit production.
- Taxon
- orange treese2
- Treatment
- lime sprayse1
- Outcome
- citrus fruit productione1
- Direction
- improvee1
- Qualifier
- under conditions of high fluoride air pollutione1
Not reportedComparator
Verbatim
e1“Results of these studies indicated that under conditions of high fluoride air pollution, application of lime sprays may improve citrus fruit production”
e2“orange trees growing in a commercial orchard”
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