Abstract
A common response to water stress is stomatal closure, which reduces fluxes of both CO 2 and water vapor. Alternatively, stomates may remain open while turgor is maintained through osmotic adjustment. The latter response should result in a greater C gain. To test this, daily whole plant C balances and water losses of cowpea plants ( Vigna unguiculata L. Walp.) were compared with those of sugarbeet plants ( Beta vulgaris L.) of equal leaf area. Under frequent irrigation and controlled environment conditions typical of warm, humid, sunny days, C gain and water‐loss rates were almost identical in the two species. When irrigation was withheld, the sugarbeet plants adjusted osmotically by 0.8 kJ kg −1 (0.8 MPa, 8 bars) and reached a daytime minimum leaf water potential of −2.6 kJ kg −1 at the time of re‐irrigation, while the cowpea plants adjusted by half as much but maintained a higher water potential (−1.2 kJ kg −1 ) by stomatal closure. At any given water potential, water‐loss rates were much smaller in the cowpea plants, but on any given day, the rates were very similar in the two species. This was because the water potential fell much more rapidly in the sugarbeet plants. The C gain rates were also similar. The comparison of these two species showed little or no C gain advantage of osmotic adjustment over stomatal closure.
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 10
Claim · model-written summary
Under frequent irrigation, cowpea and sugarbeet had almost identical carbon gain and water-loss rates.
- Taxon
- cowpea
Vigna unguiculatae1 - Outcome
- C gain and water‐loss ratese0
- Direction
- almost identicale0
- Comparator
- sugarbeete1
- Setting
- controlled environmente0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Under frequent irrigation and controlled environment conditions typical of warm, humid, sunny days, C gain and water‐loss rates were almost identical in the two species”
e1“cowpea plants ( Vigna unguiculata L. Walp.) were compared with those of sugarbeet plants ( Beta vulgaris L.)”
Claim · model-written summary
With irrigation withheld, sugarbeet adjusted osmotically by 0.8 kJ kg −1 and reached −2.6 kJ kg −1 minimum leaf water potential.
- Taxon
- sugarbeet
Beta vulgaris subsp. vulgarise0 - Treatment
- irrigation was withhelde0
- Outcome
- adjusted osmoticallye0
- Value
- 0.8 kJ kg −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When irrigation was withheld, the sugarbeet plants adjusted osmotically by 0.8 kJ kg −1 (0.8 MPa, 8 bars) and reached a daytime minimum leaf water potential of −2.6 kJ kg −1”
Claim · model-written summary
Sugarbeet reached a daytime minimum leaf water potential of −2.6 kJ kg −1.
- Taxon
- sugarbeetBeta vulgaris subsp. vulgarise0
- Outcome
- daytime minimum leaf water potentiale0
- Value
- −2.6 kJ kg −1e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the sugarbeet plants adjusted osmotically by 0.8 kJ kg −1 (0.8 MPa, 8 bars) and reached a daytime minimum leaf water potential of −2.6 kJ kg −1”
Claim · model-written summary
Cowpea adjusted osmotically by half as much as sugarbeet.
- Taxon
- cowpeaVigna unguiculatae0
- Outcome
- adjustede0
- Direction
- half as muche0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the cowpea plants adjusted by half as much but maintained a higher water potential (−1.2 kJ kg −1 ) by stomatal closure”
Claim · model-written summary
Cowpea maintained higher water potential of −1.2 kJ kg −1 by stomatal closure.
- Taxon
- cowpeaVigna unguiculatae0
- Outcome
- water potentiale0
- Direction
- highere0
- Value
- −1.2 kJ kg −1e0
- Qualifier
- stomatal closuree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the cowpea plants adjusted by half as much but maintained a higher water potential (−1.2 kJ kg −1 ) by stomatal closure”
Claim · model-written summary
At a given water potential, cowpea water-loss rates were much smaller.
- Taxon
- cowpeaVigna unguiculatae0
- Outcome
- water‐loss ratese0
- Direction
- much smallere0
- Qualifier
- any given water potentiale0
Not reportedMaterialGeneCompoundOrgan / stageInteractorTreatmentComparatorSetting
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At any given water potential, water‐loss rates were much smaller in the cowpea plants”
Claim · model-written summary
On a given day, cowpea and sugarbeet water-loss rates were very similar.
- Taxon
- cowpeaVigna unguiculatae1
- Outcome
- water‐loss ratese1
- Direction
- very similare0
- Comparator
- sugarbeete2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“on any given day, the rates were very similar in the two species”
e1“water‐loss rates were much smaller in the cowpea plants”
e2“sugarbeet plants ( Beta vulgaris L.)”
Claim · model-written summary
Sugarbeet water potential fell much more rapidly.
- Taxon
- sugarbeetBeta vulgaris subsp. vulgarise0
- Outcome
- water potentiale0
- Direction
- fell much more rapidlye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the water potential fell much more rapidly in the sugarbeet plants”
Claim · model-written summary
Carbon gain rates were similar in cowpea and sugarbeet.
- Taxon
- cowpeaVigna unguiculatae1
- Outcome
- C gain ratese0
- Direction
- similare0
- Comparator
- sugarbeete1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The C gain rates were also similar”
e1“cowpea plants ( Vigna unguiculata L. Walp.) were compared with those of sugarbeet plants ( Beta vulgaris L.)”
Claim · model-written summary
Osmotic adjustment showed little or no carbon gain advantage over stomatal closure.
- Taxon
- sugarbeetBeta vulgaris subsp. vulgarise1
- Outcome
- C gain advantagee0
- Direction
- little or noe0
- Comparator
- stomatal closuree0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The comparison of these two species showed little or no C gain advantage of osmotic adjustment over stomatal closure”
e1“cowpea plants ( Vigna unguiculata L. Walp.) were compared with those of sugarbeet plants ( Beta vulgaris L.)”