Abstract
This study investigated the effect of irrigation treatments and time of foliar applications of low-biuret urea on yield of 30-yr-old navel orange trees grown under optimal N fertilization. The experiment was carried out at the Agricultural Experiment Station of the University of California, Riverside, using split plot design with 12 replications. The two irrigation treatments were the mainplots and the urea applications were the subplots. Irrigation was withheld from one set of trees from October to March, the other set was irrigated according to commercial practice. Foliar-urea (0.17 kg/tree) was applied in November, December, January, or February. The results of the first year showed no significant differences between irrigation treatments with regard to total fruit weight or total number of fruit per tree, All trees receiving urea had significantly higher fruit weight and fruit number per tree than the control trees. The specific time of urea application had no significant effect. With respect to fruit size distribution, the irrigated treatment resulted in a significantly higher number of fruit of size 7.0-8.0 cm (box sizes 88-72). Generally, the non-irrigatd trees had more fruit of size 6.0 cm or less. No interaction between irrigation treatments and foliar urea sprays was observed.
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Claims 8
Claim · model-written summary
Irrigation treatment did not significantly change total fruit weight.
- Taxon
- NAVEL ORANGE
Citrus sinensist0 - Treatment
- irrigation treatmentse0
- Outcome
- total fruit weighte0
- Direction
- no significant differencese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“no significant differences between irrigation treatments with regard to total fruit weight or total number of fruit per tree”
Claim · model-written summary
Irrigation treatment did not significantly change fruit number per tree.
- Taxon
- NAVEL ORANGECitrus sinensist0
- Treatment
- irrigation treatmentse0
- Outcome
- total number of fruit per treee0
- Direction
- no significant differencese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“no significant differences between irrigation treatments with regard to total fruit weight or total number of fruit per tree”
Claim · model-written summary
Foliar urea significantly increased fruit weight compared with controls.
- Taxon
- NAVEL ORANGECitrus sinensist0
- Treatment
- ureae0
- Outcome
- fruit weighte0
- Direction
- highere0
- Comparator
- control treese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“All trees receiving urea had significantly higher fruit weight and fruit number per tree than the control trees”
Claim · model-written summary
Foliar urea significantly increased fruit number per tree compared with controls.
- Taxon
- NAVEL ORANGECitrus sinensist0
- Treatment
- ureae0
- Outcome
- fruit number per treee0
- Direction
- highere0
- Comparator
- control treese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“All trees receiving urea had significantly higher fruit weight and fruit number per tree than the control trees”
Claim · model-written summary
Timing of urea application had no significant effect.
- Taxon
- NAVEL ORANGECitrus sinensist0
- Treatment
- time of urea applicatione0
- Outcome
- effecte0
- Direction
- no significant effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“The specific time of urea application had no significant effect”
Claim · model-written summary
Irrigation significantly increased the count of 7.0–8.0 cm fruit.
- Taxon
- NAVEL ORANGECitrus sinensist0
- Treatment
- irrigated treatmente0
- Outcome
- number of fruit of size 7.0-8.0 cme0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“the irrigated treatment resulted in a significantly higher number of fruit of size 7.0-8.0 cm (box sizes 88-72)”
Claim · model-written summary
Nonirrigated trees generally had more fruit 6.0 cm or smaller.
- Taxon
- NAVEL ORANGECitrus sinensist0
- Treatment
- non-irrigatd treese0
- Outcome
- fruit of size 6.0 cm or lesse0
- Direction
- moree0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“the non-irrigatd trees had more fruit of size 6.0 cm or less”
Claim · model-written summary
No irrigation by foliar urea interaction was observed.
- Taxon
- NAVEL ORANGECitrus sinensist0
- Treatment
- irrigation treatments and foliar urea sprayse0
- Outcome
- interactione0
- Direction
- No interactione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“NAVEL ORANGE”
e0“No interaction between irrigation treatments and foliar urea sprays was observed”
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See all 37 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.