Abstract
Nutrients required for the growth of the embryo and endosperm of developing wheat (Triticum aestivum L.) grains are released into the endosperm cavity from the maternal tissues across the nucellar cell plasma membranes. We followed the uptake and efflux of sugars into and out of the nucellus by slicing grains longitudinally through the endosperm cavity to expose the nucellar surface to experimental solutions. Sucrose uptake and efflux are passive processes. Neither was sensitive to metabolic inhibitors, pH, or potassium concentration. p-Chloromercuribenzene sulfonate, however, strongly inhibited both uptake and efflux, although not equally. Except for p-chloromercuribenzene sensitivity, these characteristics of efflux and the insensitivity of Suc movement to turgor pressure are similar to those of sucrose release from maize pedicels, but they contrast with legume seed coats. Although the evidence is incomplete, movement appears to be carrier mediated rather than channel mediated. In vitro rates of sucrose efflux were similar to or somewhat less than in vivo rates, suggesting that transport across the nucellar cell membranes could be a factor in the control of assimilate import into the grain.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. 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 7
Claim · model-written summary
Sucrose uptake and efflux across wheat nucellar membranes are passive.
- Taxon
- wheat
Triticum aestivume1 - Outcome
- Sucrose uptake and effluxe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sucrose uptake and efflux are passive processes.”
e1“developing wheat (Triticum aestivum L.) grains”
Claim · model-written summary
Sucrose uptake and efflux were insensitive to metabolic inhibitors, pH, and potassium concentration.
- Taxon
- wheatTriticum aestivume1
- Treatment
- metabolic inhibitors, pH, or potassium concentratione0
- Outcome
- Sucrose uptake and effluxe2
- Direction
- Neither was sensitivee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Neither was sensitive to metabolic inhibitors, pH, or potassium concentration.”
e1“developing wheat (Triticum aestivum L.) grains”
e2“Sucrose uptake and efflux are passive processes.”
Claim · model-written summary
p-Chloromercuribenzene sulfonate strongly inhibited sucrose uptake and efflux, unequally.
- Taxon
- wheatTriticum aestivume1
- Treatment
- p-Chloromercuribenzene sulfonatee0
- Outcome
- uptake and effluxe0
- Direction
- strongly inhibitede0
- Qualifier
- although not equallye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“p-Chloromercuribenzene sulfonate, however, strongly inhibited both uptake and efflux, although not equally.”
e1“developing wheat (Triticum aestivum L.) grains”
Claim · model-written summary
Sucrose movement was insensitive to turgor pressure.
- Taxon
- wheatTriticum aestivume1
- Treatment
- turgor pressuree0
- Outcome
- Suc movemente0
- Direction
- insensitivitye0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the insensitivity of Suc movement to turgor pressure”
e1“developing wheat (Triticum aestivum L.) grains”
Claim · model-written summary
Sucrose movement appears carrier mediated rather than channel mediated, with incomplete evidence.
- Taxon
- wheatTriticum aestivume1
- Outcome
- Sucrose uptake and effluxe2
- Qualifier
- carrier mediated rather than channel mediatede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Although the evidence is incomplete, movement appears to be carrier mediated rather than channel mediated.”
e1“developing wheat (Triticum aestivum L.) grains”
e2“Sucrose uptake and efflux are passive processes.”
Claim · model-written summary
In vitro sucrose efflux rates were similar to or somewhat less than in vivo rates.
- Taxon
- wheatTriticum aestivume1
- Outcome
- rates of sucrose effluxe0
- Direction
- similar to or somewhat less thane0
- Comparator
- in vivo ratese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In vitro rates of sucrose efflux were similar to or somewhat less than in vivo rates”
e1“developing wheat (Triticum aestivum L.) grains”
Claim · model-written summary
Transport across nucellar membranes could control assimilate import into wheat grains.
- Taxon
- wheatTriticum aestivume1
- Outcome
- assimilate import into the graine0
- Qualifier
- transport across the nucellar cell membranese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“transport across the nucellar cell membranes could be a factor in the control of assimilate import into the grain”
e1“developing wheat (Triticum aestivum L.) grains”
The same questions in other papers
p-chloromercuribenzenesulfonate · nutrient: content · Triticum aestivum (wheat)Results agree
1 paper in the same direction as this paper
- no effect
ph · nutrient: content · Triticum aestivum (wheat)Positive and negative results
6 papers in the same direction as this paper · 11 in the opposite direction
- positive
- positive
- positive
14 papers more in this group
See all 18 papers →potassium · nutrient: content · Triticum aestivum (wheat)Positive and negative results
10 papers in the same direction as this paper · 71 in the opposite direction
- positive
- positive
- positive
78 papers more in this group
See all 82 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.