Abstract
The respective influences of the leaves and shoot apex on stimulation of internodal elongation were studied in the grapevine. Various defoliation or decapitation treatments were applied to the shoot of rooted hardwood cuttings grown in a controlled environment chamber. Concerning the foliar influences, the role of three sorts of leaves, in relation to their nodal position relative to the internode was analysed ; its own leaves, the leaves located below it and the young leaves neoformed above. The effects produced by excision of these different leaves show that the two adjacent leaves (below and above) of the internode play an essential role in the stimulation of its elongation. Among the subjacent leaves, these only at a position at least 6 nodes below promote internode growth. On the other hand, the young leaves neoformed in the upper part of the shoot have not influence. The results of decapitation experiments indicate that terminal bud contributes also to the stimulation of internodal elongation. However this influence appears only if an increment to the size (« compensatory growth ») of the leaves below the level of decapitation is not induced by the removal of the shoot tip. The leaves which realize this « compensatory growth » have indeed the ability to compensate for the laking apical bud stimulus. The influences vary with the stage of internode length. The longitudinal growth of very young internode (5 - 10 mm long) is stimulated by its own leaves, the terminal bud and leaves situated at least 6 nodes below. When the internode has reached at least 50 p. cent of its adult size, its elongation depends only on its own leaves and the apex. At the end of grown, only its own leaves stimulate lengthening. Exogenous applications of IAA, NAA and gibberellic acid (GA3) at different concentrations were also tested. GA3 at 100 mg.l-1 and 1 g.l-1 (incorporated to lanolin paste) applied to the cut surface of the petiole of the two adjacent leaves of young internode permits a normal elongation providing that apical bud is maintained. If the shoot is decapited the same treatment has almost the same effect only by supplying NAA at 1 g.l-1 to the shoot section. The functions of the three elements contributing to internodal elongation are discussed, taking in consideration both the experimental results of exogenous applications of IAA, NAA and GA3, and the possible trophic role of the leaves. It is proposed that the two adjacent leaves of the internode stimulate its longitudinal growth through a production of diffusible gibberellic substances and also, probably of nutrient elements. The role of subjacent leaves is certainly of trophic nature. Terminal bud being an auxin source, we can expect that its stimulating influence is due to the supply of this growth regulator.
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Claims 13
Claim · model-written summary
The two leaves adjacent to an internode stimulated its elongation.
VitisNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the two adjacent leaves (below and above) of the internode play an essential role in the stimulation of its elongation.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
Leaves at least six nodes below promoted internode growth.
- Organ / stage
- subjacent leavese0
- Outcome
- internode growthe0
- Direction
- promotee0
- Qualifier
- at least 6 nodes belowe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Among the subjacent leaves, these only at a position at least 6 nodes below promote internode growth.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
Young leaves newly formed in the upper shoot did not influence internode growth.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the young leaves neoformed in the upper part of the shoot have not influence.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
The terminal bud stimulated internode elongation.
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“terminal bud contributes also to the stimulation of internodal elongation.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
Compensatory leaf growth after decapitation compensated for the missing apical bud stimulus.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The leaves which realize this « compensatory growth » have indeed the ability to compensate for the laking apical bud stimulus.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
Very young internodes were stimulated by their own leaves.
- Organ / stage
- very young internodee0
- Outcome
- longitudinal growthe0
- Direction
- stimulatede0
- Qualifier
- 5 - 10 mm longe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The longitudinal growth of very young internode (5 - 10 mm long) is stimulated by its own leaves, the terminal bud and leaves situated at least 6 nodes below.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
At half adult size, internode elongation depended only on its own leaves and apex.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When the internode has reached at least 50 p. cent of its adult size, its elongation depends only on its own leaves and the apex.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
At the end of growth, only the internode’s own leaves stimulated lengthening.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At the end of grown, only its own leaves stimulate lengthening.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
GA3 applied to petioles of adjacent leaves permitted normal internode elongation when the apical bud remained.
- Treatment
- GA3 at 100 mg.l-1 and 1 g.l-1e0
- Outcome
- normal elongatione0
- Direction
- permitse0
- Qualifier
- apical bud is maintainede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“GA3 at 100 mg.l-1 and 1 g.l-1 (incorporated to lanolin paste) applied to the cut surface of the petiole of the two adjacent leaves of young internode permits a normal elongation providing that apical bud is maintained.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
After decapitation, the same GA3 treatment had nearly the same effect with NAA supplied to the cut shoot.
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“If the shoot is decapited the same treatment has almost the same effect only by supplying NAA at 1 g.l-1 to the shoot section.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
Authors propose that adjacent leaves stimulate internode growth through diffusible gibberellic substances and probably nutrients.
- Organ / stage
- two adjacent leavese0
- Compound
- diffusible gibberellic substancese0
- Outcome
- longitudinal growthe0
- Qualifier
- probably of nutrient elementse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“It is proposed that the two adjacent leaves of the internode stimulate its longitudinal growth through a production of diffusible gibberellic substances and also, probably of nutrient elements.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
Authors infer that lower leaves supply trophic support to internode growth.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The role of subjacent leaves is certainly of trophic nature.”
t0“grapevine (Vitis vinifera L.)”
Claim · model-written summary
Authors expect the terminal bud to stimulate growth through auxin supply.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Terminal bud being an auxin source, we can expect that its stimulating influence is due to the supply of this growth regulator.”
t0“grapevine (Vitis vinifera L.)”
The same questions in other papers
Gibberellic acid · growth · VitisResults differ
25 papers in the same direction as this paper · 8 in the opposite direction
- negative
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See all 34 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.