Effects of water stress on photosynthesis and carbon partitioning in soybean (Glycine max IL.IMerr.) plants grown in the field at different CO2 levels

Steven C. Huber, Hugo H. Rogers, Fred L. Mowry

Research output: Contribution to journalArticle

Abstract

The effects of water stress and CO2 enrichment on photosynthesis, assimilate export, and sucrose-P synthase activity were examined in field grown soybean plants. In general, leaves of plants grown in CO2-enriched atmospheres (300 microliters per liter above unenriched control, which was 349 ± 12 microliters per liter between 0500 and 1900 hours EST over the entire season) had higher carbon exchange rates (CER) compared to plants grown at ambient CO2, but similar rates of export and similar activities of sucrose-P synthase. On most sample dates, essentially all of the extra carbon fixed as a result of CO2enrichment was partitioned into starch. CO2-enriched plants had lower transpiration rates and therefore had a higher water use efficiency (milligrams CO2 fixed per gram H2O transpired) per unit leaf area compared to nonenriched plants. Water stress reduced CER in nonenriched plants to a greater extent than in CO2-enriched plants. As CER declined, stomatal resistance increased, but this was not the primary cause of the decrease in assimilation because internal CO2concentration remained relatively constant. Export of assimilates was less affected by water stress than was CER. When CERs were low as a result of the imposed stress, export was supported by mobilization of reserves (mainly starch). Export rate and leaf sucrose concentration were related in a curvilinear manner. When sucrose concentration was above about 12 milligrams per square decimeter, obtained with nonstressed plants at high CO2, there was no significant increase in export rate. Assimilate export rate was also correlated positively with SPS activity and the quantitative relationship varied with CER. Thus, export rate was a function of both CER and carbon partitioning.

Original languageEnglish (US)
Pages (from-to)244-249
Number of pages6
JournalPlant physiology
Volume76
Issue number1
DOIs
StatePublished - Jan 1 1984

Fingerprint

Photosynthesis
Dehydration
Soybeans
Glycine max
water stress
Carbon
photosynthesis
soybeans
carbon
sucrose
Starch
Sucrose
starch
Plant Leaves
Atmosphere
water use efficiency
stomatal conductance
leaves
assimilation (physiology)
transpiration

ASJC Scopus subject areas

  • Physiology
  • Genetics
  • Plant Science

Cite this

Effects of water stress on photosynthesis and carbon partitioning in soybean (Glycine max IL.IMerr.) plants grown in the field at different CO2 levels. / Huber, Steven C.; Rogers, Hugo H.; Mowry, Fred L.

In: Plant physiology, Vol. 76, No. 1, 01.01.1984, p. 244-249.

Research output: Contribution to journalArticle

@article{fa50cc5ca9a14b1d8063a6ef65396e04,
title = "Effects of water stress on photosynthesis and carbon partitioning in soybean (Glycine max IL.IMerr.) plants grown in the field at different CO2 levels",
abstract = "The effects of water stress and CO2 enrichment on photosynthesis, assimilate export, and sucrose-P synthase activity were examined in field grown soybean plants. In general, leaves of plants grown in CO2-enriched atmospheres (300 microliters per liter above unenriched control, which was 349 ± 12 microliters per liter between 0500 and 1900 hours EST over the entire season) had higher carbon exchange rates (CER) compared to plants grown at ambient CO2, but similar rates of export and similar activities of sucrose-P synthase. On most sample dates, essentially all of the extra carbon fixed as a result of CO2enrichment was partitioned into starch. CO2-enriched plants had lower transpiration rates and therefore had a higher water use efficiency (milligrams CO2 fixed per gram H2O transpired) per unit leaf area compared to nonenriched plants. Water stress reduced CER in nonenriched plants to a greater extent than in CO2-enriched plants. As CER declined, stomatal resistance increased, but this was not the primary cause of the decrease in assimilation because internal CO2concentration remained relatively constant. Export of assimilates was less affected by water stress than was CER. When CERs were low as a result of the imposed stress, export was supported by mobilization of reserves (mainly starch). Export rate and leaf sucrose concentration were related in a curvilinear manner. When sucrose concentration was above about 12 milligrams per square decimeter, obtained with nonstressed plants at high CO2, there was no significant increase in export rate. Assimilate export rate was also correlated positively with SPS activity and the quantitative relationship varied with CER. Thus, export rate was a function of both CER and carbon partitioning.",
author = "Huber, {Steven C.} and Rogers, {Hugo H.} and Mowry, {Fred L.}",
year = "1984",
month = "1",
day = "1",
doi = "10.1104/pp.76.1.244",
language = "English (US)",
volume = "76",
pages = "244--249",
journal = "Plant Physiology",
issn = "0032-0889",
publisher = "American Society of Plant Biologists",
number = "1",

}

TY - JOUR

T1 - Effects of water stress on photosynthesis and carbon partitioning in soybean (Glycine max IL.IMerr.) plants grown in the field at different CO2 levels

AU - Huber, Steven C.

AU - Rogers, Hugo H.

AU - Mowry, Fred L.

PY - 1984/1/1

Y1 - 1984/1/1

N2 - The effects of water stress and CO2 enrichment on photosynthesis, assimilate export, and sucrose-P synthase activity were examined in field grown soybean plants. In general, leaves of plants grown in CO2-enriched atmospheres (300 microliters per liter above unenriched control, which was 349 ± 12 microliters per liter between 0500 and 1900 hours EST over the entire season) had higher carbon exchange rates (CER) compared to plants grown at ambient CO2, but similar rates of export and similar activities of sucrose-P synthase. On most sample dates, essentially all of the extra carbon fixed as a result of CO2enrichment was partitioned into starch. CO2-enriched plants had lower transpiration rates and therefore had a higher water use efficiency (milligrams CO2 fixed per gram H2O transpired) per unit leaf area compared to nonenriched plants. Water stress reduced CER in nonenriched plants to a greater extent than in CO2-enriched plants. As CER declined, stomatal resistance increased, but this was not the primary cause of the decrease in assimilation because internal CO2concentration remained relatively constant. Export of assimilates was less affected by water stress than was CER. When CERs were low as a result of the imposed stress, export was supported by mobilization of reserves (mainly starch). Export rate and leaf sucrose concentration were related in a curvilinear manner. When sucrose concentration was above about 12 milligrams per square decimeter, obtained with nonstressed plants at high CO2, there was no significant increase in export rate. Assimilate export rate was also correlated positively with SPS activity and the quantitative relationship varied with CER. Thus, export rate was a function of both CER and carbon partitioning.

AB - The effects of water stress and CO2 enrichment on photosynthesis, assimilate export, and sucrose-P synthase activity were examined in field grown soybean plants. In general, leaves of plants grown in CO2-enriched atmospheres (300 microliters per liter above unenriched control, which was 349 ± 12 microliters per liter between 0500 and 1900 hours EST over the entire season) had higher carbon exchange rates (CER) compared to plants grown at ambient CO2, but similar rates of export and similar activities of sucrose-P synthase. On most sample dates, essentially all of the extra carbon fixed as a result of CO2enrichment was partitioned into starch. CO2-enriched plants had lower transpiration rates and therefore had a higher water use efficiency (milligrams CO2 fixed per gram H2O transpired) per unit leaf area compared to nonenriched plants. Water stress reduced CER in nonenriched plants to a greater extent than in CO2-enriched plants. As CER declined, stomatal resistance increased, but this was not the primary cause of the decrease in assimilation because internal CO2concentration remained relatively constant. Export of assimilates was less affected by water stress than was CER. When CERs were low as a result of the imposed stress, export was supported by mobilization of reserves (mainly starch). Export rate and leaf sucrose concentration were related in a curvilinear manner. When sucrose concentration was above about 12 milligrams per square decimeter, obtained with nonstressed plants at high CO2, there was no significant increase in export rate. Assimilate export rate was also correlated positively with SPS activity and the quantitative relationship varied with CER. Thus, export rate was a function of both CER and carbon partitioning.

UR - http://www.scopus.com/inward/record.url?scp=84957868892&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84957868892&partnerID=8YFLogxK

U2 - 10.1104/pp.76.1.244

DO - 10.1104/pp.76.1.244

M3 - Article

AN - SCOPUS:84957868892

VL - 76

SP - 244

EP - 249

JO - Plant Physiology

JF - Plant Physiology

SN - 0032-0889

IS - 1

ER -