Abstract
During 1947 and 1948, in various districts throughout southern California, 29 comparisons were made between fruit-drop from non-sprayed Valencia orange trees and that from trees sprayed with 2,4-D at concentrations from 4 to 48 p.p.m. Application of 2,4-D at low volumes was made six months before drop, as well as after drop had begun. While the average reduction in fruit-drop from the sprayed trees was 35.1 per cent, in some cases it was as high as 64, and in others, as low as 5 per cent. Studies were also made of the possibility of increasing fruit size of Valencias by use of 2,4-D. In an experiment begun in 1948, 17 different chemicals were applied to Valencia trees at full bloom. Only 2,4-D and 2,4,5-T induced a significant increase in fruit size. Data were obtained from eight additional experiments using actual field-scale applications. Determinations of the effect of the sprays on size and grade of fruit were based on packing house information. As a result of the spray, there was a gain of 28.0 packed boxes of fruit size 220 and larger, and a decrease of 19.8 boxes of fruit size 252 and smaller, per 100 trees sprayed. Periodic measurements showed that larger fruit sizes resulting from use of 2,4-D were due to an increased growth rate. As fruits grew older, they seemed to become less responsive to 2,4-D. In commercial practice, it is suggested that during the 16-week period after flowering, this diminishing response be compensated for by corresponding increases in the concentration of 2,4-D applied.
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Claims 8
Claim · model-written summary
2,4-D sprays reduced average Valencia orange fruit drop by 35.1 per cent.
- Taxon
- Valencia oranges
Citrus sinensist0 - Treatment
- 2,4-Dt0
- Outcome
- fruit-drope0
- Direction
- reductione0
- Value
- 35.1 per cente0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the average reduction in fruit-drop from the sprayed trees was 35.1 per cent”
t0“Effects of 2,4-D and related substances on fruit-drop, yield, size, and quality of Valencia oranges”
Claim · model-written summary
Only 2,4-D significantly increased Valencia fruit size.
- Taxon
- Valencia orangesCitrus sinensist0
- Treatment
- 2,4-De0
- Outcome
- fruit sizee0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Only 2,4-D and 2,4,5-T induced a significant increase in fruit size”
t0“Valencia oranges”
Claim · model-written summary
Only 2,4,5-T significantly increased Valencia fruit size.
- Taxon
- Valencia orangesCitrus sinensist0
- Treatment
- 2,4,5-Te0
- Outcome
- fruit sizee0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Only 2,4-D and 2,4,5-T induced a significant increase in fruit size”
t0“Valencia oranges”
Claim · model-written summary
Sprays increased packed boxes of fruit size 220 and larger by 28.0 per 100 trees.
- Taxon
- Valencia orangesCitrus sinensist0
- Treatment
- spraye0
- Outcome
- packed boxes of fruit size 220 and largere0
- Direction
- gaine0
- Value
- 28.0 packed boxese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“As a result of the spray, there was a gain of 28.0 packed boxes of fruit size 220 and larger, and a decrease of 19.8 boxes of fruit size 252 and smaller, per 100 trees sprayed”
t0“Valencia oranges”
Claim · model-written summary
Sprays decreased boxes of fruit size 252 and smaller by 19.8 per 100 trees.
- Taxon
- Valencia orangesCitrus sinensist0
- Treatment
- spraye0
- Outcome
- boxes of fruit size 252 and smallere0
- Direction
- decreasee0
- Value
- 19.8 boxese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“As a result of the spray, there was a gain of 28.0 packed boxes of fruit size 220 and larger, and a decrease of 19.8 boxes of fruit size 252 and smaller, per 100 trees sprayed”
t0“Valencia oranges”
Claim · model-written summary
Larger fruit under 2,4-D resulted from increased growth rate.
- Taxon
- Valencia orangesCitrus sinensist0
- Treatment
- 2,4-De0
- Outcome
- larger fruit sizese0
- Direction
- increasede0
- Qualifier
- growth ratee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“larger fruit sizes resulting from use of 2,4-D were due to an increased growth rate”
t0“Valencia oranges”
Claim · model-written summary
Older fruits appeared less responsive to 2,4-D.
- Taxon
- Valencia orangesCitrus sinensist0
- Organ / stage
- fruitse0
- Treatment
- 2,4-De0
- Outcome
- responsivee0
- Direction
- lesse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“As fruits grew older, they seemed to become less responsive to 2,4-D”
t0“Valencia oranges”
Claim · model-written summary
The authors suggest increasing 2,4-D concentration over the 16-week period after flowering.
- Taxon
- Valencia orangesCitrus sinensist0
- Outcome
- corresponding increases in the concentration of 2,4-D appliede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“during the 16-week period after flowering, this diminishing response be compensated for by corresponding increases in the concentration of 2,4-D applied”
t0“Valencia oranges”
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See all 77 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.