Abstract
The role of potassium (K(+)) and calcium (Ca(2+)) in the regulation of plant growth and development is complex and needs a diverse range of physiological studies. Both elements are essential for satisfactory crop production. Here, the effects of K(+) and Ca(2+) ions on endogenous growth and growth in the presence of either indole-3-acetic acid (IAA) or fusicoccin (FC) were studied in maize (Zea mays) coleoptiles. Membrane potentials of coleoptile parenchymal cells, incubated in media containing IAA, FC and different concentrations of K(+) and Ca(2+), were also determined. Growth experiments have shown that in the absence of K(+) in the incubation medium, both endogenous and IAA- or FC-induced growth were significantly inhibited by 0.1 and 1 mM Ca(2+), respectively, while in the presence of 1 mM K(+) they were inhibited only by 1 mM Ca(2+). At 10 mM K(+), endogenous growth and growth induced by either IAA or FC did not depend on Ca(2+) concentration. TEA-Cl, a potassium channel blocker, added 1 h before IAA or FC, caused a reduction of growth by 59 or 45 %, respectively. In contrast to TEA-Cl, verapamil, the Ca(2+) channel blocker, did not affect IAA- and FC-induced growth. It was also found that in parenchymal cells of maize coleoptile segments, membrane potential (Em) was strongly affected by the medium K(+), independently of Ca(2+). However, lack of Ca(2+) in the incubation medium significantly reduced the IAA- and FC-induced membrane potential hyperpolarization. TEA-Cl applied to the control medium in the same way as in growth experiments caused Em hyperpolarization synergistic with hyperpolarization produced by IAA or FC. Verapamil did not change either the Em of parenchymal cells incubated in the control medium or the IAA- and FC-induced membrane hyperpolarization. The data presented here have been discussed considering the role of K(+) uptake channels in regulation of plant cell growth.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. 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 10
Claim · model-written summary
Without potassium, 0.1 mM calcium significantly inhibited endogenous and IAA-induced growth.
- Organ / stage
- coleoptilese1
- Treatment
- 0.1 and 1 mM Ca(2+)e0
- Outcome
- endogenous and IAA- or FC-induced growthe0
- Direction
- inhibitede0
- Comparator
- absence of K(+)e0
Zea maysOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the absence of K(+) in the incubation medium, both endogenous and IAA- or FC-induced growth were significantly inhibited by 0.1 and 1 mM Ca(2+), respectively”
e1“maize (Zea mays) coleoptiles”
Claim · model-written summary
At 1 mM potassium, only 1 mM calcium inhibited growth.
- Treatment
- 1 mM Ca(2+)e0
- Outcome
- endogenous and IAA- or FC-induced growthe2
- Direction
- inhibitede0
- Comparator
- 1 mM K(+)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the presence of 1 mM K(+) they were inhibited only by 1 mM Ca(2+)”
e1“maize (Zea mays) coleoptiles”
e2“both endogenous and IAA- or FC-induced growth”
Claim · model-written summary
At 10 mM potassium, endogenous and IAA- or FC-induced growth did not depend on calcium concentration.
- Outcome
- endogenous growth and growth induced by either IAA or FCe0
- Direction
- did not depende0
- Qualifier
- At 10 mM K(+)e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At 10 mM K(+), endogenous growth and growth induced by either IAA or FC did not depend on Ca(2+) concentration”
e1“maize (Zea mays) coleoptiles”
Claim · model-written summary
TEA-Cl reduced IAA-induced growth by 59%.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“TEA-Cl, a potassium channel blocker, added 1 h before IAA or FC, caused a reduction of growth by 59 or 45 %, respectively”
e1“maize (Zea mays) coleoptiles”
Claim · model-written summary
TEA-Cl reduced FC-induced growth by 45%.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“TEA-Cl, a potassium channel blocker, added 1 h before IAA or FC, caused a reduction of growth by 59 or 45 %, respectively”
e1“maize (Zea mays) coleoptiles”
Claim · model-written summary
Verapamil did not affect IAA- and FC-induced growth.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“verapamil, the Ca(2+) channel blocker, did not affect IAA- and FC-induced growth”
e1“maize (Zea mays) coleoptiles”
Claim · model-written summary
Medium potassium strongly affected coleoptile cell membrane potential independently of calcium.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“membrane potential (Em) was strongly affected by the medium K(+), independently of Ca(2+)”
e1“parenchymal cells of maize coleoptile segments”
Claim · model-written summary
Absence of calcium significantly reduced IAA-induced membrane hyperpolarization.
- Treatment
- lack of Ca(2+)e0
- Outcome
- IAA- and FC-induced membrane potential hyperpolarizatione0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“lack of Ca(2+) in the incubation medium significantly reduced the IAA- and FC-induced membrane potential hyperpolarization”
e1“maize (Zea mays) coleoptiles”
Claim · model-written summary
TEA-Cl caused membrane hyperpolarization synergistic with IAA or FC.
- Treatment
- TEA-Cle0
- Outcome
- Em hyperpolarizatione0
- Direction
- hyperpolarizatione0
- Comparator
- control mediume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“TEA-Cl applied to the control medium in the same way as in growth experiments caused Em hyperpolarization synergistic with hyperpolarization produced by IAA or FC”
e1“maize (Zea mays) coleoptiles”
Claim · model-written summary
Verapamil did not change control membrane potential or IAA- and FC-induced hyperpolarization.
- Treatment
- Verapamile0
- Outcome
- IAA- and FC-induced membrane hyperpolarizatione0
- Direction
- did not changee0
- Comparator
- control mediume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Verapamil did not change either the Em of parenchymal cells incubated in the control medium or the IAA- and FC-induced membrane hyperpolarization”
e1“maize (Zea mays) coleoptiles”
The same questions in other papers
calcium(2+) · molecular: metabolites · Zea mays (maize)Positive and negative results
5 papers in the same direction as this paper · 2 in the opposite direction
This paper is about lacking the nutrient, so it counts the other way round here.
- no effect
- no effect
- positive
4 papers more in this group
See all 8 papers →calcium(2+) · growth · Zea mays (maize)Positive and negative results
2 papers in the same direction as this paper · 14 in the opposite direction
- positive
- positive
- positive
13 papers more in this group
See all 17 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.