Abstract
Vegetative growth control of apples (Malus × domestica Borkh.) is necessary to maintain a balance between growth and cropping. Pruning is a labour-intensive management practice to achieve this and intrinsically stimulates new growth. Prohexadione-calcium (PC) is a plant bio-regulator that effectively regulat es the shoot extension growth of apples and other tree fruits. Previous research has demonstrated that its efficacy can vary based on the use of spray surfactants and adjuvants. This study investigated the efficacy of two rates of Apogee™, the commercial form of PC, used in combination with the spray surfactants Sylgard 309 and LI 700, on extension shoot growth and yield parameters. Experiments were conducted in Ontario on Empire and Nova Scotia on Royal Court™ Cortland apples. Treatments of 0, 75 or 125 mg L -1 PC, with and without either 0.5% (vol/vol.) LI 700 surfactant or 0.05% (vol/vol) Sylgard 309 surfactant were applied to Empire trees, and 75 or 125 mg L -1 PC, with or without 0.5% (vol/vol) LI 700, were applied to Royal Court™ trees. An untreated control treatment was also included for comparison purposes. A total of two sprays were applied to the Empire trees and a total of three sprays were applied to the Royal Court™ trees. PC significantly decreased the vegetative growth of Empire and Royal Court™ trees by approximately 18 to 44%, respectively, and the efficacy of PC was enhanced when combined with either Sylgard 309 or LI 700 surfactant. No additional benefit in vegetative growth control was gained when using Apogee™ at rates of 125 mg L -1 PC, relative to 75 mg L -1 PC. The rate of Apogee™ did not influence the number of fruit or yield per tree or mean fruit size of either cultivar. For Empire, LI 700 and Sylgard 309 significantly reduced the number of fruit per tree, resulting in lower yields and crop densities. In addition, higher mean fruit weights, and a greater distribution of fruit in the larger size categories were observed for LI 700. Fruit from Royal Court trees treated with the highest rate of Apogee™ had higher crop densities, poorer coloured fruit, and a higher percentage of fruit less than 60 mm in diameter. These data provide support for the use of alternative surfactants with Apogee™ other than those listed on the US and Canadian product labels. Key words: Apogee™, Empire, Cortland, Regalis, calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate, surfactant
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Claims 13
Claim · model-written summary
Prohexadione-calcium reduced vegetative growth of Empire apple trees by approximately 18%.
- Taxon
- apple
Malus domesticat0 - Material
- Empiree0
- Treatment
- PCe0
- Outcome
- vegetative growthe0
- Direction
- decreasede0
- Value
- 18e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“PC significantly decreased the vegetative growth of Empire and Royal Court™ trees by approximately 18 to 44%, respectively”
t0“apple”
Claim · model-written summary
Prohexadione-calcium reduced vegetative growth of Royal Court apple trees by approximately 44%.
- Taxon
- appleMalus domesticat0
- Material
- Royal Court™e0
- Treatment
- PCe0
- Outcome
- vegetative growthe0
- Direction
- decreasede0
- Value
- 44%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“PC significantly decreased the vegetative growth of Empire and Royal Court™ trees by approximately 18 to 44%, respectively”
t0“apple”
Claim · model-written summary
Sylgard 309 enhanced prohexadione-calcium control of apple vegetative growth.
- Taxon
- appleMalus domesticat0
- Treatment
- Sylgard 309e0
- Outcome
- efficacy of PCe0
- Direction
- enhancede0
- Comparator
- PCe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the efficacy of PC was enhanced when combined with either Sylgard 309 or LI 700 surfactant”
t0“apple”
Claim · model-written summary
LI 700 enhanced prohexadione-calcium control of apple vegetative growth.
- Taxon
- appleMalus domesticat0
- Treatment
- LI 700 surfactante0
- Outcome
- efficacy of PCe0
- Direction
- enhancede0
- Comparator
- PCe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the efficacy of PC was enhanced when combined with either Sylgard 309 or LI 700 surfactant”
t0“apple”
Claim · model-written summary
Increasing Apogee from 75 to 125 mg L -1 PC gave no additional vegetative growth control.
- Taxon
- appleMalus domesticat0
- Treatment
- Apogee™ at rates of 125 mg L -1 PCe0
- Outcome
- vegetative growth controle0
- Direction
- No additional benefite0
- Comparator
- 75 mg L -1 PCe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“No additional benefit in vegetative growth control was gained when using Apogee™ at rates of 125 mg L -1 PC, relative to 75 mg L -1 PC.”
t0“apple”
Claim · model-written summary
Apogee rate did not influence fruit count, yield per tree or mean fruit size in either cultivar.
- Taxon
- appleMalus domesticat0
- Treatment
- rate of Apogee™e0
- Outcome
- number of fruit or yield per tree or mean fruit sizee0
- Direction
- did not influencee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The rate of Apogee™ did not influence the number of fruit or yield per tree or mean fruit size of either cultivar.”
t0“apple”
Claim · model-written summary
LI 700 reduced fruit number, yield and crop density in Empire apples.
- Taxon
- appleMalus domesticat0
- Material
- Empiree0
- Treatment
- LI 700e0
- Outcome
- number of fruit per treee0
- Direction
- reducede0
- Qualifier
- lower yields and crop densitiese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For Empire, LI 700 and Sylgard 309 significantly reduced the number of fruit per tree, resulting in lower yields and crop densities.”
t0“apple”
Claim · model-written summary
Sylgard 309 reduced fruit number, yield and crop density in Empire apples.
- Taxon
- appleMalus domesticat0
- Material
- Empiree0
- Treatment
- Sylgard 309e0
- Outcome
- number of fruit per treee0
- Direction
- reducede0
- Qualifier
- lower yields and crop densitiese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For Empire, LI 700 and Sylgard 309 significantly reduced the number of fruit per tree, resulting in lower yields and crop densities.”
t0“apple”
Claim · model-written summary
LI 700 increased Empire apple mean fruit weight and share of fruit in larger size categories.
- Taxon
- appleMalus domesticat0
- Treatment
- LI 700e0
- Outcome
- mean fruit weightse0
- Direction
- highere0
- Qualifier
- greater distribution of fruit in the larger size categoriese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“higher mean fruit weights, and a greater distribution of fruit in the larger size categories were observed for LI 700.”
t0“apple”
Claim · model-written summary
Royal Court apples receiving the highest Apogee rate had higher crop densities.
- Taxon
- appleMalus domesticat0
- Material
- Royal Courte0
- Treatment
- highest rate of Apogee™e0
- Outcome
- crop densitiese0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fruit from Royal Court trees treated with the highest rate of Apogee™ had higher crop densities”
t0“apple”
Claim · model-written summary
Royal Court apples receiving the highest Apogee rate had poorer fruit color.
- Taxon
- appleMalus domesticat0
- Material
- Royal Courte0
- Treatment
- highest rate of Apogee™e0
- Outcome
- coloured fruite0
- Direction
- poorere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fruit from Royal Court trees treated with the highest rate of Apogee™ had higher crop densities, poorer coloured fruit”
t0“apple”
Claim · model-written summary
Royal Court apples receiving the highest Apogee rate had a higher share of fruit below 60 mm diameter.
- Taxon
- appleMalus domesticat0
- Material
- Royal Courte0
- Treatment
- highest rate of Apogee™e0
- Outcome
- percentage of fruit less than 60 mm in diametere0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fruit from Royal Court trees treated with the highest rate of Apogee™ had higher crop densities, poorer coloured fruit, and a higher percentage of fruit less than 60 mm in diameter.”
t0“apple”
Claim · model-written summary
The authors support using alternative surfactants with Apogee beyond those on US and Canadian labels.
- Taxon
- appleMalus domesticat0
- Outcome
- use of alternative surfactants with Apogee™e0
- Qualifier
- other than those listed on the US and Canadian product labelse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“These data provide support for the use of alternative surfactants with Apogee™ other than those listed on the US and Canadian product labels.”
t0“apple”
The same questions in other papers
prohexadione-calcium · control · Malus domestica (apple)Positive and negative results
2 reporting no difference from an alternative
- positive
- positive
prohexadione-calcium · growth · Malus domestica (apple)Positive and negative results
18 papers in the same direction as this paper · 2 in the opposite direction · 1 reporting no difference from an alternative
- negative
- positive
- positive
18 papers more in this group
See all 22 papers →surfactant · control · Malus domestica (apple)Results agree
1 paper in the same direction as this paper
- positive
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.