Abstract
Faster regrowth of a stressed alfalfa ( Medicago sativa L.) crop compared to an unstressed crop after rewatering has been reported. The bases of this compensatory response are unknown, but they may be important to understanding adaptation to water stress and to developing crop water management strategies. Our objective was to determine the effect of stress induced by water deficit on photoassimilate partitioning and the utilization of stored assimilates during regrowth of alfalfa. Field and greenhouse experiments were conducted using cultivars differing in winterhardiness. Plants were subjected to water stress (plant water potential [ψ W > −1.5 MPa), pulse‐labeled with 14 CO 2 , and sampled following 0, 1, 14, 21, and 28‐d translocation periods. Following the 14‐d sampling, herbage was harvested and water stress was removed. Cultivars contrasting in winterhardiness responded similarly to water stress. Stressed and control plants (ψ W > −1.0 MPa) contained similar amounts of radiocarbon per unit mass of herbage at the onset of the translocation period. Water stress reduced herbage dry mass and did not alter root dry mass compared to the control. Stressed plant roots contained 73 and 114% more total plant radioactivity (TPR) than the control at the 1 and 14‐d translocation periods, respectively. Water stress significantly increased root starch and TPR percentage in the starch fraction, but had much smaller effects on root soluble‐sugar concentration and TPR percentage of the root sugar fraction. Herbage regrowth mass following harvest and rewatering of the waterstressed plants was similar to that of the control. Compared to the control, water‐stressed alfalfa has greater total nonstructural carbohydrates in the roots, apparently due to increased photoassimilate partitioning to the roots. However, the greater root carbohydrate concentrations did not result in compensatory herbage regrowth following rewatering.
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 12
Claim · model-written summary
Cultivars contrasting in winterhardiness responded similarly to water stress.
Not reportedTaxon
Verbatim
e0“Cultivars contrasting in winterhardiness responded similarly to water stress.”
Claim · model-written summary
Stressed and control plants had similar herbage radiocarbon per unit mass at translocation onset.
- Treatment
- Stressede0
- Outcome
- radiocarbon per unit mass of herbagee0
- Direction
- similare0
- Comparator
- control plantse0
Not reportedTaxon
Verbatim
e0“Stressed and control plants (ψ W > −1.0 MPa) contained similar amounts of radiocarbon per unit mass of herbage at the onset of the translocation period.”
Claim · model-written summary
Water stress reduced herbage dry mass relative to control.
Not reportedTaxon
Verbatim
e0“Water stress reduced herbage dry mass and did not alter root dry mass compared to the control.”
Claim · model-written summary
Water stress did not alter root dry mass relative to control.
Not reportedTaxon
Verbatim
e0“Water stress reduced herbage dry mass and did not alter root dry mass compared to the control.”
Claim · model-written summary
Stressed roots had 73% more total plant radioactivity than control at day 1.
- Treatment
- Stressede0
- Outcome
- total plant radioactivity (TPR)e0
- Direction
- moree0
- Value
- 73e0
- Qualifier
- 1 and 14‐d translocation periodse0
- Comparator
- controle0
Not reportedTaxon
Verbatim
e0“Stressed plant roots contained 73 and 114% more total plant radioactivity (TPR) than the control at the 1 and 14‐d translocation periods, respectively.”
Claim · model-written summary
Stressed roots had 114% more total plant radioactivity than control at day 14.
- Treatment
- Stressede0
- Outcome
- total plant radioactivity (TPR)e0
- Direction
- moree0
- Value
- 114%e0
- Qualifier
- 1 and 14‐d translocation periodse0
- Comparator
- controle0
Not reportedTaxon
Verbatim
e0“Stressed plant roots contained 73 and 114% more total plant radioactivity (TPR) than the control at the 1 and 14‐d translocation periods, respectively.”
Claim · model-written summary
Water stress significantly increased root starch.
Not reportedTaxonComparator
Verbatim
e0“Water stress significantly increased root starch and TPR percentage in the starch fraction”
Claim · model-written summary
Water stress significantly increased the percentage of total plant radioactivity in the root starch fraction.
Not reportedTaxonComparator
Verbatim
e0“Water stress significantly increased root starch and TPR percentage in the starch fraction”
Claim · model-written summary
Water stress had much smaller effects on root soluble sugar concentration and root sugar fraction radioactivity.
- Outcome
- root soluble‐sugar concentration and TPR percentage of the root sugar fractione0
- Direction
- smallere0
Not reportedTaxonTreatmentComparator
Verbatim
e0“had much smaller effects on root soluble‐sugar concentration and TPR percentage of the root sugar fraction.”
Claim · model-written summary
Herbage regrowth mass after harvest and rewatering was similar to control.
- Treatment
- rewatering of the waterstressed plantse0
- Outcome
- Herbage regrowth masse0
- Direction
- similare0
- Comparator
- controle0
Not reportedTaxon
Verbatim
e0“Herbage regrowth mass following harvest and rewatering of the waterstressed plants was similar to that of the control.”
Claim · model-written summary
Water-stressed alfalfa had greater root total nonstructural carbohydrates than control.
- Taxon
- alfalfa
Medicago sativae0 - Treatment
- water‐stressede0
- Outcome
- total nonstructural carbohydrates in the rootse0
- Direction
- greatere0
- Comparator
- controle0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Compared to the control, water‐stressed alfalfa has greater total nonstructural carbohydrates in the roots, apparently due to increased photoassimilate partitioning to the roots.”
Claim · model-written summary
The greater root carbohydrate concentrations apparently resulted from increased photoassimilate partitioning to roots.
- Outcome
- total nonstructural carbohydrates in the rootse0
- Qualifier
- increased photoassimilate partitioning to the rootse0
Not reportedTaxon
Verbatim
e0“greater total nonstructural carbohydrates in the roots, apparently due to increased photoassimilate partitioning to the roots.”
The same questions in other papers
drought · quality: sugar starch · Medicago sativa (alfalfa)Positive and negative results
1 in the opposite direction
- negative
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.