Abstract
Abstract ‘York Imperial’ apple seedlings ( Malus domestica Borkh.) grown in nutrient solution cultures with decreased water potential to− 1.0 bar by polyethylene glycol (PEG) increased water consumption, photosynthesis rate (P n ), and stomatal conductance (C s ). High light preconditioning of the plants used in this experiment was probably the reason why− 1.0 bar water potential in the nutrient solution was not low enough to induce apple seedling responses typical of water-stressed plants. However, application of PEG stress (−1.0 bar), to K-sprayed (K 2 SO 4 , −0.5%) trees lowered seedling water consumption Pn, and C s . Potassium sprays alone did not significantly affect water consumption, Pn or C s . When the water potential of the nutrient solution of PEG stressed plants was further decreased to −2.5 bars, unsprayed trees started to wilt within 2 days while sprayed trees did not. It is proposed that earlier stomatal closure of K-sprayed trees when stressed, already at low level of water stress (−1.0 bar), prevented plant water depletion when stress level was increased. This in turn delayed commencement of plant wilting. Potassium sprays also increased root:shoot ratio and root K concentration in PEG-stressed plants. These responses of K-sprayed trees could also contribute to greater tolerance to higher levels of water stress.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc-nd. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 8
Claim · model-written summary
At −1.0 bar PEG treatment increased water use, photosynthesis, and stomatal conductance.
- Taxon
- apple seedlings
Malus domesticat0 - Treatment
- polyethylene glycol (PEG)e0
- Outcome
- water consumption, photosynthesis rate (P n ), and stomatal conductance (C s )e0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“decreased water potential to− 1.0 bar by polyethylene glycol (PEG) increased water consumption, photosynthesis rate (P n ), and stomatal conductance (C s )”
t0“Apple Seedlings”
Claim · model-written summary
PEG stress lowered water use, photosynthesis, and conductance in K-sprayed seedlings.
- Taxon
- apple seedlingsMalus domesticat0
- Treatment
- PEG stress (−1.0 bar)e0
- Outcome
- seedling water consumption Pn, and C se0
- Direction
- lowerede0
- Qualifier
- K-sprayed (K 2 SO 4 , −0.5%) treese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“application of PEG stress (−1.0 bar), to K-sprayed (K 2 SO 4 , −0.5%) trees lowered seedling water consumption Pn, and C s”
t0“Apple Seedlings”
Claim · model-written summary
Potassium sprays did not significantly affect water use, photosynthesis, or conductance alone.
- Taxon
- apple seedlingsMalus domesticat0
- Treatment
- Potassium sprays alonee0
- Outcome
- water consumption, Pn or C se0
- Direction
- did not significantly affecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Potassium sprays alone did not significantly affect water consumption, Pn or C s”
t0“Apple Seedlings”
Claim · model-written summary
At −2.5 bars, unsprayed PEG-stressed trees wilted within two days.
- Taxon
- apple seedlingsMalus domesticat0
- Outcome
- started to wilte0
- Qualifier
- within 2 dayse0
- Comparator
- sprayed treese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“unsprayed trees started to wilt within 2 days while sprayed trees did not”
t0“Apple Seedlings”
Claim · model-written summary
At −2.5 bars, sprayed PEG-stressed trees did not wilt within two days.
- Taxon
- apple seedlingsMalus domesticat0
- Outcome
- sprayed trees did note0
- Qualifier
- within 2 dayse0
- Comparator
- unsprayed treese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“unsprayed trees started to wilt within 2 days while sprayed trees did not”
t0“Apple Seedlings”
Claim · model-written summary
Potassium sprays increased root to shoot ratio in PEG-stressed plants.
- Taxon
- apple seedlingsMalus domesticat0
- Treatment
- Potassium sprayse0
- Outcome
- root:shoot ratioe0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Potassium sprays also increased root:shoot ratio and root K concentration in PEG-stressed plants”
t0“Apple Seedlings”
Claim · model-written summary
Potassium sprays increased root potassium concentration in PEG-stressed plants.
- Taxon
- apple seedlingsMalus domesticat0
- Treatment
- Potassium sprayse0
- Outcome
- root K concentratione0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Potassium sprays also increased root:shoot ratio and root K concentration in PEG-stressed plants”
t0“Apple Seedlings”
Claim · model-written summary
The authors propose earlier stomatal closure prevented depletion and delayed wilting in K-sprayed trees.
- Taxon
- apple seedlingsMalus domesticat0
- Outcome
- delayed commencement of plant wiltinge0
- Qualifier
- earlier stomatal closuree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“earlier stomatal closure of K-sprayed trees when stressed, already at low level of water stress (−1.0 bar), prevented plant water depletion when stress level was increased. This in turn delayed commencement of plant wilting”
t0“Apple Seedlings”
The same questions in other papers
potassium · physiology: photosynthesis · Malus domestica (apple)Positive and negative results
1 paper in the same direction as this paper · 2 in the opposite direction
- positive
- positive
- negative
potassium · growth · Malus domestica (apple)Positive and negative results
8 papers in the same direction as this paper · 2 in the opposite direction
- negative
- no effect
- positive
7 papers more in this group
See all 11 papers →potassium · nutrient: content · Malus domestica (apple)Positive and negative results
12 papers in the same direction as this paper · 6 in the opposite direction
- negative
- no effect
- no effect
15 papers more in this group
See all 19 papers →application · physiology: photosynthesis · Malus domestica (apple)Positive and negative results
11 papers in the same direction as this paper · 9 in the opposite direction
- positive
- positive
- positive
17 papers more in this group
See all 21 papers →application · growth · Malus domestica (apple)Positive and negative results
75 papers in the same direction as this paper · 31 in the opposite direction
- no effect
- no effect
- no effect
103 papers more in this group
See all 107 papers →application · nutrient: content · Malus domestica (apple)Positive and negative results
99 papers in the same direction as this paper · 16 in the opposite direction
- no effect
- negative
- no effect
112 papers more in this group
See all 116 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.