Effects of Water Stress on Carbon Exchange Rate and Activities of Photosynthetic Enzymes in Leaves of Sugarcane (Saccharum Sp.)

1996 ◽  
Vol 23 (6) ◽  
pp. 719 ◽  
Author(s):  
YC Du ◽  
Y Kawamitsu ◽  
A Nose ◽  
S Hiyane ◽  
S Murayama ◽  
...  
Keyword(s):  
Exchange Rate ◽  
Water Stress ◽  
Stomatal Closure ◽  
Total Soluble Protein ◽  
Carbon Exchange ◽  
Bisphosphate Carboxylase ◽  
Pyruvate Orthophosphate Dikinase ◽  
Photosynthetic Enzymes ◽  
Orthophosphate Dikinase ◽  
Saccharum Sp

The responses of carbon exchange rate (CER), stomatal conductance (gs), activities of phosphoenolpyruvate carboxylase (PEPcase), NADP malic enzyme (NADP-ME), ribulose-1,5- bisphosphate carboxylase (Rubisco), fructose-1,6-bisphosphatase (FBPase) and pyruvate, orthophosphate dikinase (PPDK), and contents of chlorophyll (Chl) and total soluble protein (Tsp) in leaves of sugar cane (Saccharum sp. cv. NiF4) to gradually developed water stress were investigated. The initial inhibitions of CER, gs, activities of the photosynthetic enzymes and contents of Chl and Tsp were observed from leaf water potentials (Ψw) of -0.37 MPa. During water stress, CER and gs, decreased in a non-linear way, activities of the five enzymes and contents of Chl and Tsp decreased linearly with decreasing leaf Ψw. The changes of gs the photosynthetic enzymes, Chl and Tsp were highly related to the changes of CER. The decline in CER during water stress was caused by both stomatal and non- stomatal limitations. Above leaf �w of -0.85 MPa, the decline in CER was caused by stomatal closure, below -0.85 MPa, the decline in CER was caused by non-stornatal limitation. Among non-stomatal components, PPDK activities decreased 9.1 times during water stress, much more than other enzymes which decreased from 2 to 4 times. Measured PPDK activities were only a little higher than the corresponding CER values at various leaf Ψw suggesting that PPDK is very likely to be the limiting enzyme to photosynthesis under water stress.

Responses to water stress of enzyme activities and metabolite levels in relation to sucrose and starch synthesis, the Calvin cycle and the C4 pathway in sugarcane (Saccharum sp.) leaves

1998 ◽  
Vol 25 (2) ◽  
pp. 253 ◽  
Author(s):  
Y.-C. Du ◽  
A. Nose ◽  
K. Wasano ◽  
Y. Uchida
Keyword(s):  
Water Stress ◽  
Enzyme Activities ◽  
Stomatal Closure ◽  
Starch Synthesis ◽  
Calvin Cycle ◽  
Severe Water Stress ◽  
C4 Pathway ◽  
Saccharum Sp ◽  
Almost All ◽  
Mild Water Stress

During a slowly induced water stress, almost all measured activities of enzymes, including the important enzymes associated with the Calvin cycle, the C4 pathway, and sucrose and starch synthesis, and the pool sizes of metabolites, including hexose phosphates, 3-phosphoglycerate, triose phosphates, malate, pyruvate and PEP, in leaves of sugarcane (Saccharum sp. cv. NiF4) were not or only moderately reduced by mild water stress (above –0.9 MPa leaf water potential (Ψw)), and the magnitudes of reductions in those parameters were less than the reductions in photosynthetic rates. We conclude that the biochemical processes of sucrose and starch synthesis, the Calvin cycle and the C4 pathway in sugarcane leaves were not seriously affected by mild water stress, and the changes in those processes were not the cause for the decline in photosynthesis; mild water stress induced decline in photosynthesis is caused by stomatal closure. Under severe water stress (–1.2 MPa leaf Ψw), most metabolite levels and enzyme activities decreased significantly compared with those under mild water stress. But the enzyme activities and metabolite levels relating to sucrose and starch synthesis, and the Calvin cycle still remained at high levels compared with the corresponding photosynthetic rate. PPDK activity and pyruvate content decreased to very low levels. It is suggested that PPDK is a possible limiting enzyme for photosynthesis in leaves of sugarcane under severe water stress.

scholarly journals Changes in Abundance of Enzymes Involved in Organic Acid, Amino Acid and Sugar Metabolism, and Photosynthesis during the Ripening of Blackberry Fruit

2009 ◽  
Vol 134 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Franco Famiani ◽  
Robert P. Walker
Keyword(s):  
Amino Acid ◽  
Gel Electrophoresis ◽  
Phosphoenolpyruvate Carboxykinase ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Sugar Metabolism ◽  
Large Decrease ◽  
Bisphosphate Carboxylase ◽  
Pyruvate Orthophosphate Dikinase ◽  
Orthophosphate Dikinase

Although information is available regarding the content of various metabolites such as sugars and organic/amino acids in blackberry (Rubus L.), little is known about its enzyme composition. The aim of this study was to investigate changes in the abundance of various enzymes during the ripening of blackberry. Blackberry is an aggregate fruit, composed of a receptacle and several drupelets attached to it, which in turn, are composed of the flesh (mesocarp plus epicarp) and seed enclosed in the endocarp; therefore, these parts were analyzed separately along with the pedicel. The enzymes studied participate in organic/amino acid and sugar metabolism and photosynthesis, processes known to be important in fruit development. These enzymes were phosphoenolpyruvate carboxykinase [PEPCK (EC:4.1.1.49)], phosphoenolpyruvate carboxylase [PEPC (EC:4.1.1.31)], pyruvate, orthophosphate dikinase [PPDK (EC:2.7.9.1)], cytosolic aspartate aminotransferase [cyt AspAT (EC:2.6.1.1)], aldolase (EC:4.1.2.13), glutamine synthetase [GS (EC:6.3.1.2)], and ribulose-1,5-bisphosphate carboxylase/oxygenase [RUBISCO (EC:4.1.1.39)]. To avoid problems in measuring enzyme activity, the approach taken was to use antibodies specific for each enzyme in conjunction with immunoblotting of sodium dodecyl sulfate polyacrylamide gel electrophoresis. During ripening, there were marked changes in abundance of several of these enzymes and these changes were dependent on the tissue investigated. PEPCK appeared when organic acids decreased in the flesh and was only detected in this tissue, whereas PPDK was not detected in any tissue. In the flesh, there was a large decrease in abundance of RUBISCO, plastidic GS, and plastidic aldolase, but little change in cytosolic GS, cytosolic aldolase, and PEPC. In seeds, there was a decrease in the abundance of all enzymes. In the receptacle and pedicel, apart from a large decrease in RUBISCO in the receptacle, there was little change in enzyme abundance.

scholarly journals Methomyl Injury to Carbon Exchange Rates and Related Processes in Cotton

2017 ◽  
Author(s):  
C.E. Salem ◽  
J.T. Cothren ◽  
C.R. Benedict
Keyword(s):  
Exchange Rate ◽  
Chlorophyll Fluorescence ◽  
Stomatal Conductance ◽  
Carbon Exchange ◽  
Rubisco Activity ◽  
Bisphosphate Carboxylase ◽  
Chlorophyll Fluorescence Parameter ◽  
Fluorescence Parameter ◽  
Time Courses ◽  
Induced Changes

AbstractSome insecticides have the potential to cause varying levels of phytotoxicity. This study examined 1) the time courses of photosynthetic injury in cotton (Gossypium hirsutisms L.) leaves treated with methomyl [S-methyl-N-[(methyl carbamoyl)oxy]-thioacetimidate] and 2) the relationships between carbon exchange rate (CER), stomatal conductance, the chlorophyll fluorescence parameter FX/FP, and ribulose-1,5-bisphosphate carboxylase/ oxygenase (rubisco) activity. Plots were sprayed with either 0 or 0.84 kg methomyl·ha-1 when cotton was in mid-reproductive growth. Starting on the day of spraying, CER, stomatal conductance, FX/FP, and rubisco activity were measured daily for five consecutive days [4, 28, 52, 76 and 100 hours after spraying (HAS)]. In methomyl-treated leaves, CER decreased within hours after spraying, reached their lowest point at 28 HAS in experiment I and 76 HAS in experiment II, then recovered near-control levels by 100 HAS. At their lowest points, CER of methomyl-treated leaves decreased from 20 to 50% compared to controls. Stomatal conductance, FX/FP, and rubisco activity followed similar patterns to CER. Stomatal conductance was more closely related to CER than were FX/FP and rubisco activity. Chlorophyll fluorescence recovered more quickly than did CER. Rubisco activity did not decrease till after CER. From the parameters measured in this study, stomatal conductance appeared to be the major factor influencing methomyl-induced changes in CER, although all three parameters may be involved in the process of CER change.AbbreviationsCERcarbon exchange raterubiscoribulose-1,5-bisphosphate carboxylase/ oxygenaseDATdays after treatmentHAShours after spraying

Relationships Between Apparent Nitrogen Fixation and Carbon Exchange Rate in Alfalfa 1

Crop Science ◽  
1980 ◽  
Vol 20 (4) ◽  
pp. 491-495 ◽  
Author(s):  
J. E. Sheehy ◽  
K. A. Fishbeck ◽  
D. A. Phillips
Keyword(s):  
Nitrogen Fixation ◽  
Exchange Rate ◽  
Carbon Exchange

Inhibition of cambial activity in Abies balsamea by internal water stress: role of abscisic acid

1975 ◽  
Vol 53 (24) ◽  
pp. 3041-3050 ◽  
Author(s):  
C. H. A. Little
Keyword(s):  
Abscisic Acid ◽  
Water Stress ◽  
Indoleacetic Acid ◽  
Stomatal Closure ◽  
Abies Balsamea ◽  
Cambial Activity ◽  
Inhibitory Effect ◽  
Internal Water ◽  
Endogenous Aba

In experiments with attached and detached shoots of balsam fir, Abies balsamea L., synthetic (±)abscisic acid (ABA) (1) reduced photosynthesis and transpiration by inducing stomatal closure, (2) inhibited indoleacetic acid (IAA) - induced cambial activity in photosynthesizing and non-photosynthesizing shoots, and (3) inhibited the basipetal movement of [14C]IAA. Neither gibberellic acid nor kinetin counteracted the inhibitory effect of (±)ABA on IAA-induced cambial activity. In addition it was demonstrated that increasing the internal water stress increased the level of endogenous ABA in the phloem–cambial region of bark peelings and decreased the basipetal movement of [14C]IAA through branch sections. On the basis of these findings it is proposed that internal water stress inhibits cambial activity, partly through increasing the level of ABA; the ABA acts to decrease the provision of carbohydrates and auxin that are required for cambial growth.

scholarly journals Hormonal and Hydroxycinnamic Acids Profiles in Banana Leaves in Response to Various Periods of Water Stress

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Jalel Mahouachi ◽  
María F. López-Climent ◽  
Aurelio Gómez-Cadenas
Keyword(s):  
Water Stress ◽  
Leaf Gas Exchange ◽  
Stomatal Closure ◽  
Photosynthetic Performance ◽  
Hydroxycinnamic Acids ◽  
Cinnamic Acids ◽  
Gas Exchange Parameters ◽  
Banana Leaves ◽  
Indole 3 Acetic Acid

The pattern of change in the endogenous levels of several plant hormones and hydroxycinnamic acids in addition to growth and photosynthetic performance was investigated in banana plants (Musa acuminatacv. “Grand Nain”) subjected to various cycles of drought. Water stress was imposed by withholding irrigation for six periods with subsequent rehydration. Data showed an increase in abscisic acid (ABA) and indole-3-acetic acid (IAA) levels, a transient increase in salicylic acid (SA) concentration, and no changes in jasmonic acid (JA) after each period of drought. Moreover, the levels of ferulic (FA) and cinnamic acids (CA) were increased, and plant growth and leaf gas exchange parameters were decreased by drought conditions. Overall, data suggest an involvement of hormones and hydroxycinnamic acids in plant avoidance of tissue dehydration. The increase in IAA concentration might alleviate the senescence of survival leaves and maintained cell elongation, and the accumulation of FA and CA could play a key role as a mechanism of photoprotection through leaf folding, contributing to the effect of ABA on inducing stomatal closure. Data also suggest that the role of SA similarly to JA might be limited to a transient and rapid increase at the onset of the first period of stress.

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