Carbon Dioxide Exchange in Water‐stressed Sorghum<sup>1</sup>

Shearman, Linda L.; Eastin, Jerry D.; Sullivan, C. Y.; Kinbacher, E. J.

doi:10.2135/cropsci1972.0011183x001200040002x

Cited by 27 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Non-stomatal inhibition has been ascribed either to decreased photosynthetic electron transport, photophosphorylation or due to enzyme activities associated with photosynthesis [4,6,11,12,21,23]. Other photosynthetic enzymes such as ribose-5-phosphate isomerase and ribose-5phosphate kinase in barley and PEP carboxylase in sorghum were also relatively insensitive to water stress [8,24]. Similar results have been reported in other crops also [8,16,21,26].…”

Section: Discussionsupporting

confidence: 52%

Effect of water stress on photosynthesis and in vitro activities of the PCR cycle enzymes in pigeonpea (Cajanus cajan L.)

1985

View full text Add to dashboard Cite

Leaf water potential was decreased by withholding irrigation to provide three levels of stress described as mild ({ie69-1}) moderate ({ie69-2}) and severe ({ie69-3}). The specific activity of NADP linked glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, aldolase, phosphogluco-isomerase and RuBP carboxylase decreased under mild stress, but the activity of phosphoglucomutase showed an increase whilst ribulose-5-phosphate kinase was least affected. With further decrease in water potential, the activity of NADP linked glyceraldehyde-3-phosphate dehydrogenase and aldolase showed a decrease, whereas, the activities of fructose-1,6-bisphosphatase, phosphoglycerate kinase, phosphogulcomutase and RuBP carboxylase increased. Net CO2 fixation decreased sharply with stress, whereas, respiration and photorespiration increased in moderate stress, but decreased under severe stress. Stomatal resistance also increased with decrease in water potential. It seems that in vitro enzyme activities of PCR cycle are not responsible for decreased photosynthesis in pigeonpea under short term water stress.

show abstract

Section: Discussionsupporting

confidence: 52%

Effect of water stress on photosynthesis and in vitro activities of the PCR cycle enzymes in pigeonpea (Cajanus cajan L.)

1985

View full text Add to dashboard Cite

show abstract

“…Nevertheless, this observation agrees with some published studies in other species (Lawlor, 1976;Loboda, 1993;Flexas et al, 2005). However, several other authors have found different results on the effect of water stress on respiration, ranging from decrease (Brix, 1962;Brown and Thomas, 1980;Palta and Nobel, 1989;Escalona et al, 1999;Ghashghaie et al, 2001;Haupt-Herting et al, 2001) to stimulation (Upchurch et al, 1955;Shearmann et al, 1972;Zagdań ska, 1995). In all cases, as in this study, changes in respiration were much less than those in photosynthesis, causing a significant increase in the respiration/photosynthesis ratio under water stress, indicating that the role of respiration becomes more important as water stress develops.…”

Section: The Effect Of Water Stress On Leaf Respirationcontrasting

confidence: 53%

Effects of Water Stress on Respiration in Soybean Leaves

et al. 2005

View full text Add to dashboard Cite

The effect of water stress on respiration and mitochondrial electron transport has been studied in soybean (Glycine max) leaves, using the oxygen-isotope-fractionation technique. Treatments with three levels of water stress were applied by irrigation to replace 100%, 50%, and 0% of daily water use by transpiration. The levels of water stress were characterized in terms of lightsaturated stomatal conductance (g s ): well irrigated (g s . . Although net photosynthesis decreased by 40% and 70% under mild and severe water stress, respectively, the total respiratory oxygen uptake (V t ) was not significantly different at any water-stress level. However, severe water stress caused a significant shift of electrons from the cytochrome to the alternative pathway. The electron partitioning through the alternative pathway increased from 10% to 12% under well-watered or mild water-stress conditions to near 40% under severe water stress. Consequently, the calculated rate of mitochondrial ATP synthesis decreased by 32% under severe water stress. Unlike many other stresses, water stress did not affect the levels of mitochondrial alternative oxidase protein. This suggests a biochemical regulation (other than protein synthesis) that causes this mitochondrial electron shift.Water stress is considered one of the most important factors limiting plant performance and yield worldwide (Boyer, 1982). Effects of water stress on a plant's physiology, including growth (McDonald and Davies, 1996), signaling pathways (Chaves et al., 2003), gene expression (Bray, 1997(Bray, , 2002, and leaf photosynthesis (Lawlor and Cornic, 2002;Flexas et al., 2004), have been studied extensively. Surprisingly, compared with other physiological processes, studies examining the effects of water stress on respiration are few (Hsiao, 1973; Amthor, 1989), despite the importance of respiration in ecosystem annual net productivity (Valentini et al., 1999) and the fact that ecosystem respiration is strongly affected by water availability (Bowling et al., 2002). Another important point to consider is the effect of water stress on the electron partitioning between the cytochrome and the cyanide-resistant, alternative pathway and its consequences for ATP synthesis. Unfortunately, the few studies that have focused on alternative respiration as affected by water stress (Zagdańska, 1995;Collier and Cummins, 1996; González-Meler et al., 1997) used specific inhibitors for the cytochrome (KCN) and alternative (salicylhydroxamic acid [SHAM]) respiratory pathways; this methodology is now known to be invalid (Millar et al., 1995;Day et al., 1996;Lambers et al., 2005). Currently, the only available system to measure electron partitioning between the two respiratory pathways and their actual activities is the use of the oxygen-isotope-fractionation technique McDonald et al., 2003;Ribas-Carbo et al., 2005). This technique is based on the fact that the two terminal oxidases fractionate 18 O differently, with the cytochrome oxidase discriminating less than the alternative oxid...

show abstract

“…The extent ef the after=eRect ~a r i e s with the degree of stress experienced (Bengtson et al 1977) and among species ( (Brix 1962;Sionit and Kramer 1976;Davies and Kozlowski 1977 ;Dorffling et al 1977 ;Mansfield et al 1978). The more drought resistant C, crop plants like Sorghum bicolor (Shearman et al 1972;Mansfield et al 1978) and C, pasture grasses recover rapidly. For example, the after-effect usually lasted less than 24 h in P. maximum in these experiments.…”

Section: After-efsects and Abscisic Acidmentioning

confidence: 99%

Recovery After Water Stress of Leaf Gas Exchange in Panicum maximum var. trichoglume

Ludlow¹,

Ng²,

Ford³

1980

Functional Plant Biol.

View full text Add to dashboard Cite

Net photosynthesis of the last fully expanded leaf of P. maximum var. tvichoglume was able to recover from leaf water potentials as low as -92 bar. The degree of stress experienced during the single drying cycle did not influence the maximum net photosynthetic rate attained during recovery, but the time taken to reach the maximum increased with the degree of stress experienced. During the first 24 h, the rate of recovery of net photosynthesis was mainly determined by the rate at which the water status improved. Leaves which experienced water potentials less than c. -40 bar had a slower rate of recovery of water potential than less stressed leaves. This was partially offset by higher rates of net photosynthesis. Furthermore, the relationship between leaf water potential and net photosynthesis recorded during the drying cycle was different from those measured during recovery. Thus different relationships must be used in models simulating behaviour during water stress and subsequent recovery.Stomata1 resistance exerted greater control than intracellular resistance over net photosynthesis in the recovery phase, irrespective of the water potential before rewatering or whether plants were preconditioned to stress. Although abscisic acid concentration was positively related to leaf water potential and stomatal resistance during the drying cycle, the relationship between abscisic acid concentration and stomatal resistance during recovery was poor or absent. Sucrose and amino-acid nitrogen accumulated during stress and decreased during recovery. However, the level of nonstructural carbohydrates or nitrogen compounds in the recovery phase did not appear to influence net photosynthetic rate or its components. In fact, the reverse appeared to occur: the rate of photosynthesis and growth seemed to determine the levels of these compounds.

show abstract

Carbon Dioxide Exchange in Water‐stressed Sorghum¹

Cited by 27 publications

References 0 publications

Effect of water stress on photosynthesis and in vitro activities of the PCR cycle enzymes in pigeonpea (Cajanus cajan L.)

Effect of water stress on photosynthesis and in vitro activities of the PCR cycle enzymes in pigeonpea (Cajanus cajan L.)

Effects of Water Stress on Respiration in Soybean Leaves

Recovery After Water Stress of Leaf Gas Exchange in Panicum maximum var. trichoglume

Contact Info

Product

Resources

About

Carbon Dioxide Exchange in Water‐stressed Sorghum1

Cited by 27 publications

References 0 publications

Effect of water stress on photosynthesis and in vitro activities of the PCR cycle enzymes in pigeonpea (Cajanus cajan L.)

Effect of water stress on photosynthesis and in vitro activities of the PCR cycle enzymes in pigeonpea (Cajanus cajan L.)

Effects of Water Stress on Respiration in Soybean Leaves

Recovery After Water Stress of Leaf Gas Exchange in Panicum maximum var. trichoglume

Contact Info

Product

Resources

About

Carbon Dioxide Exchange in Water‐stressed Sorghum¹