Photosynthesis under stressful environments: An overview

May combine two claims.

In salt-tolerant species Chl content increases, whereas in salt-sensitive species it decreases under saline regimes; Chl accumulation has been proposed as a biochemical indicator of salt tolerance in crops, but this is not always associated with salt tolerance and depends on plant species or cultivar.

“For example, it is generally known that in salttolerant species, Chl content increases, whereas it decreases in salt-sensitive species under saline regimes (Hamada and El-Enany 1994, Khan et al. 2009, Akram and Ashraf 2011).”

• Also stated in: § Stress-induced changes · hedged

  “Although the above-cited studies suggest that Chl accumulation could be used as biochemical marker for salt tolerance in different crops, in some other studies, Chl accumulation under saline stress is not always associated with salt tolerance.”

• Also stated in: § Stress-induced changes · plain

  “Therefore using Chl accumulation as an indicator of salt tolerance depends on the nature of the plant species or cultivar.”

• cites Hamada and El-Enany 1994 sourceDisputed

  Split into 2 atoms — 0 confirmed, 0 partially supported, 2 disputed, 0 misattributed, 0 unverifiable. Expand the claim to see per-atom verdicts.

  Checked by a reasoning model — may be wrong.

  Experimental — accuracy not yet measured
• cites Khan et al. 2009Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Akram and Ashraf 2011 sourceNot checked — no full text of the source

May combine two claims.

Stomata usually close during initial stages of drought stress, increasing WUE; stomatal closure inhibits transpiration more than CO2 diffusion into leaf tissues.

“A number of reports showed that stomata usually close during the initial stages of drought stress resulting in increased WUE (net CO 2 assimilation rate/transpiration).Stomata closure is known to have a more inhibitory effect on transpiration of water than that on CO 2 diffusion into the leaf tissues (Chaves et al. 2009, Sikuku et al. 2010).”

• cites Chaves et al. 2009 sourcePartly supported

  The Introduction (page unavailable) says stomata close in response to drought-related signals and that, under mild stress, a small decline in stomatal conductance may save water and improve water-use efficiency. It does not say closure usually occurs in the initial stages of drought or explicitly compare its inhibitory effects on transpiration and CO2 diffusion; it also qualifies the efficiency benefit as a possibility. (LLM, conf=0.84)

  Experimental — accuracy not yet measured
• cites Sikuku et al. 2010Not checked — no full text of the source

May combine two claims.

Salt-induced alterations in leaf Chl content could be due to impaired biosynthesis or accelerated pigment degradation; during Chl degradation, Chl b may convert to Chl a, increasing Chl a.

“The salt-induced alterations in a leaf Chl content could be due to impaired biosynthesis or accelerated pigment degradation.However, during the process of Chl degradation, Chl b may be converted into Chl a, thus resulting in the increased content of Chl a (Fang et al. 1998, Eckardt 2009).”

• cites Fang et al. 1998 sourcePartly supported

  The Introduction (page unavailable) says chlorophyll b is converted to chlorophyll a during degradation. The discussion of the chlorophyll a/b ratio (page unavailable) suggests this conversion may explain a rising ratio during bean-leaf senescence, not an increase in the absolute content of chlorophyll a. The paper studies senescence under air and low oxygen, not salt-induced changes. (LLM, conf=0.88)

  Experimental — accuracy not yet measured
• cites Eckardt 2009 sourcePartly supported

  The “IN BRIEF A New Chlorophyll Degradation Pathway” section discusses chlorophyll breakdown during leaf senescence, supporting the general possibility of pigment degradation. It does not address salt-induced changes or impaired biosynthesis, and it does not say that chlorophyll b converts to chlorophyll a or that this increases chlorophyll a content. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

May combine two claims.

Heat stress causes membrane disruption, particularly of thylakoid membranes, inhibiting activities of membrane-associated electron carriers and enzymes, ultimately reducing photosynthesis.

“Heat stress causes membrane disruption, particularly of thylakoid membranes, thereby inhibiting the activities of membrane-associated electron carriers and enzymes (Ristic et al. 2008, Rexroth et al. 2011), which ultimately results in a reduced rate of photosynthesis.”

• cites Ristic et al. 2008 sourceNot checked — no full text of the source
• cites Rexroth et al. 2011 sourcePartly supported

  The Discussion (page not available) links thylakoid membrane fluidity and zeaxanthin content to heat tolerance, supporting a connection between heat and membrane stability. It does not say that heat stress disrupts membranes, inhibits electron carriers or enzymes, or thereby reduces photosynthesis. (LLM, conf=0.77)

  Experimental — accuracy not yet measured

May combine two claims. The quote only partly states this claim.

High-temperature stress reduces Chl biosynthesis by destroying enzymes involved in Chl biosynthesis; ALAD activity decreases, and ALA and Pchlide biosynthesis are impaired under low and high temperature.

“A number of reports indicate that plants exposed to high-temperature stress show reduced Chl biosynthesis (Efeoglu and Terzioglu 2009, Balouchi 2010, Reda and Mandoura 2011).”

• Also stated in: § Stress-induced changes · plain

  “The impaired Chl biosynthesis is the first of the processes occurring in plastids affected by the high temperature (Dutta et al. 2009, Li et al. 2010).”

• Also stated in: § Stress-induced changes · plain

  “The inhibition of Chl biosynthesis under high-temperature regimes results from a destruction of numerous enzymes involved in the mechanism of Chl biosynthesis (Dutta et al. 2009, Reda andMandoura 2011).”

• cites Efeoglu and Terzioglu 2009 sourceNot checked — no full text of the source
• cites Balouchi 2010 sourceCould not verify

  The Introduction (page unavailable) discusses heat-related changes in chlorophyll fluorescence and photosystem II efficiency, not reduced chlorophyll biosynthesis. Searches for biosynthesis, ALAD, ALA, Pchlide, and the proposed enzyme mechanism found no passage addressing those claims in our copy. (LLM, conf=0.72)

  Experimental — accuracy not yet measured
• cites Reda and Mandoura 2011Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

The Fv/Fm ratio determines maximum quantum efficiency of PSII and indicates overall photosynthetic capacity; in healthy leaves it is usually close to 0.8, and lower values indicate photoinhibition under stress.

“The F v /F m ratio is an important parameter, which determines the maximum quantum efficiency of PSII.It provides a measure of the rate of linear electron transport, hence, an indication of overall photosynthetic capacity (Jamil et al. 2007, Tang et al. 2007, Balouchi 2010).”

• Also stated in: § Stress-induced changes · plain

  “In healthy leaves, F v /F m value is usually close to 0.8 in most plant species, therefore a lower value indicates that a proportion of PSII reaction centers is damaged or inactivated, a phenomenon, termed as photoinhibition, commonly observed in plants under stress (Baker and Rosenqvist 2004, Zlatev 2009, Vaz and Sharma 2011).”

• cites Jamil et al. 2007 sourceNot checked — no full text of the source
• cites Tang et al. 2007 sourceNot checked — no full text of the source
• cites Balouchi 2010 sourcePartly supported

  The Introduction (page not provided) says Fv/Fm indicates maximum PSII efficiency, gives 0.83 for healthy plants, and reports declines under water and heat stress. It does not say that Fv/Fm measures the rate of linear electron transport or overall photosynthetic capacity, or explicitly identify lower values as photoinhibition. (LLM, conf=0.86)

  Experimental — accuracy not yet measured

May combine two claims.

Heat stress inhibits the OEC and PSII reaction center, with the OEC more sensitive; the PSII core complex denatures at about 60°C and LHCII proteins at about 74°C; release of the 33 kDa extrinsic protein is considered the major reason for heat-induced OEC inactivation.

“It has been also reported that plants exposed to heat stress for even a short time experience the inhibition of the OEC and the reaction center of PSII (Wang et al. 2010, Hamdani et al. 2011), although the former is more sensitive to heat than the latter.”

• Also stated in: § Stress-induced changes · plain

  “Smith and Low (1989) reported that the PSII core complex undergoes denaturation at about 60 °C, whereas the denaturation of LHCII proteins occurs at about 74°C (Smith et al. 1989).”

• Also stated in: § Stress-induced changes · hedged

  “The major reason considered for heat-induced inactivation of OEC was the release of 33 kDa extrinsic protein from the complex (Zhang et al. 2011).”

• cites Wang et al. 2010 sourcePartly supported

  Split into 3 atoms — 0 confirmed, 2 partially supported, 0 disputed, 0 misattributed, 1 unverifiable. Expand the claim to see per-atom verdicts.

  Experimental — accuracy not yet measured
• cites Hamdani et al. 2011 sourceNot checked — no full text of the source
• cites Smith and Low (1989) sourceNot checked — no full text of the source

May combine two claims.

Salinity stress significantly affects both stomatal and nonstomatal regulation of photosynthesis; salt stress at the reproductive stage decreases net CO2 assimilation rate and stomatal conductance in wheat genotypes; salt-induced osmotic stress reduces photosynthesis via decreased ATP production from impaired electron transport.

“It is known that salinity stress, similarly to other abiotic stresses, can significantly affect both stomatal and nonstomatal regulation of photosynthesis (Ashraf 2004, Saibo et al. 2009).”

• Also stated in: § Stress-induced changes · plain

  “Salt stress imposed at the reproductive stage was reported to decrease the net CO 2 assimilation rate and stomatal conductance of intact leaves in various wheat genotypes (Shahbaz andAshraf 2007, Perveen et al. 2010).”

• Also stated in: § Stress-induced changes · plain

  “The inhibitory effect of salt-induced osmotic stress (water deficit) on the rate of photosynthesis was related to decreased production of ATP due to the impaired electron transport (Moud andMaghsoudi 2008, Curtiss et al. 2011).”

• cites Ashraf 2004 sourceNot checked — no full text of the source
• cites Saibo et al. 2009 sourceSupported
• cites Shahbaz andAshraf 2007Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

An increase in the amount of Rubisco can be beneficial for plant survival under harsh environmental conditions because a positive relationship of leaf Rubisco contents with PN has been reported in most C3 plants.

“The increase in the amount of Rubisco can be beneficial for the survival of plants under harsh environmental conditions, because a positive relationship of leaf Rubisco contents with P N has been reported in most C 3 plants (Taub 2010, Makino 2011).”

• cites Taub 2010Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Makino 2011 sourcePartly supported

  In “Difference in Rubisco Properties between Rice and Wheat” (page not provided), the paper says Rubisco amount strongly affects photosynthetic rate and suggests greater allocation to Rubisco may help explain higher rates in rice and wheat. It does not establish a positive relationship between leaf Rubisco content and photosynthesis in most C3 plants, or show that increasing Rubisco improves survival under harsh conditions. (LLM, conf=0.85)

  Experimental — accuracy not yet measured

May combine two claims.

Drought stress can adversely affect levels and activities of different enzymes involved in photosynthesis, thereby impairing carbohydrate synthesis and WUE, which in turn adversely affects overall plant yield.

“Similarly as the salt stress, drought stress can also adversely affect levels and activities of different enzymes involved in the mechanism of photosynthesis, thereby impairing the synthesis of carbohydrates as well as WUE of plants, which in turn adversely affects the overall plant yield (Kumar andSingh 2009, Gill et al. 2011).”

• cites Kumar andSingh 2009Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Gill et al. 2011 sourcePartly supported

  The Results and Discussion report that cadmium stress reduced photosynthetic characteristics in mustard, and the paper concludes that cadmium stress inhibited photosynthesis and yield. Those findings concern cadmium, not drought; our copy does not establish the claimed effects on carbohydrate synthesis or water-use efficiency (WUE). (LLM, conf=0.84)

  Experimental — accuracy not yet measured

Probably not a substantial claim: may not pass S3 (load-bearing).

Down-regulation of photosynthesis depends more on the availability of CO2 in the chloroplast than on leaf water content or water potential.

“Such a strong relationship led to the proposal that the down-regulation of photosynthesis depends more on the availability of CO 2 in the chloroplast than on leaf water content or water potential (Flexas et al. 2002, Saibo et al. 2009, Galmes et al. 2011).”

• cites Flexas et al. 2002 sourceNot checked — no full text of the source
• cites Saibo et al. 2009 sourcePartly supported

  In “Photosynthesis and related mechanisms affected by abiotic stress” (page not provided), the review describes lower chloroplast CO₂ availability as a proposed explanation for reduced photosynthesis under very severe drought, but says evidence for reduced RuBP supply instead conflicts with that view. A reference title contrasts chloroplast CO₂ concentration with relative water content for Rubisco activity; the review does not establish the claimed comparison with leaf water potential or present the proposal as a general rule. (LLM, conf=0.82)

  Experimental — accuracy not yet measured
• cites Galmes et al. 2011 sourcePartly supported

  The Results and discussion (‘Causes for reduced Rubisco activity under water stress’; no page available) report that Rubisco activity correlated more strongly with chloroplastic CO2 concentration than with relative water content. The Concluding remarks likewise propose CO2 availability rather than leaf dehydration as the mediator of reduced Rubisco activity. These passages support the comparison for Rubisco activity, but do not establish it for the down-regulation of photosynthesis as a whole or make a direct comparison with leaf water potential. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

May combine two claims.

Stomata closure under stress leads to lower intercellular CO2, which in turn causes deactivation of Rubisco and other enzymes such as sucrose-phosphate synthase and nitrate reductase.

“One of the most prominent effects of various stresses is the stomata closure, which leads to a lower concentration of intercellular CO 2 , which in turn causes deactivation of Rubisco as well as other enzymes such as sucrosephosphate synthase (SPS) and nitrate reductase (Chaves et al. 2009, Mumm et al. 2011).”

• cites Chaves et al. 2009 sourceSupported
• cites Mumm et al. 2011 sourceNot checked — no full text of the source

May combine two claims.

HY5, a bZIP-type transcription factor, is mainly involved in the regulation of CAB gene expression by light and may also have a significant role in abiotic stress tolerance.

“For example, a transcription factor LONG HYPOCOTYL 5 (HY5), a bZIP-type, was reported to be mainly involved in the regulation of CAB gene expression by light, although it may also exhibit a significant role in abiotic stress tolerance (Maxwell et al. 2003, Saibo et al. 2009).”

• cites Maxwell et al. 2003 sourceNot checked — no full text of the source
• cites Saibo et al. 2009 sourcePartly supported

  In “Transcription factors mediating the non-stomatal responses to abiotic stress,” the paper identifies HY5 as a bZIP transcription factor involved in light regulation of CAB expression. It says HY5 may play a role in the abiotic stress response, but does not establish a significant role in stress tolerance; it also notes a lack of direct evidence for HY5 regulation of photosynthesis-related genes under abiotic stress. (LLM, conf=0.84)

  Experimental — accuracy not yet measured

May combine two claims.

In tobacco transgenic lines overexpressing maize PEPC, C4-PEPC activity increased two-fold compared with nontransformed plants, but the transgenic and nontransformed lines did not differ significantly in net CO2 assimilation rate.

“However, in all these transgenic lines, although the activity of C 4 -PEPC increased two-fold compared with that in nontransformed plants, the transgenic and nontransformed lines did not differ significantly in the net CO 2 assimilation rate.”

• cites Hudspeth et al. 1992 sourcePartly supported

  In “Biochemical and Physiological Analyses of Transgenic Tobacco” (page unavailable), the paper reports about twofold higher PPC activity in the four tested transgenic plants. It says photosynthesis rates for lines BVI-6400 (1)–(3) were within experimental error of the control, but line (4) had a significantly lower rate. Thus the claim that none of the lines differed significantly is not supported. (LLM, conf=0.91)

  Experimental — accuracy not yet measured
• cites Benfey andChua 1990Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Kogami et al. 1994 sourceNot checked — no full text of the source

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

MAPKs respond to a variety of extracellular stimuli including osmotic stress and heat shock and pass information from sensors to cellular processes in all eukaryotes.

“MAPKs respond to a variety of extracellular stimuli including mitogens, proinflammatory cytokines, osmotic stress, and heat shock (Fig. 4), and they pass on information from sensors to cellular processes in all eukaryotes (Nakagami et al. 2005, Diédhiou et al. 2008, Inagaki et al. 2008).”

• cites Nakagami et al. 2005 sourceNot checked — no full text of the source
• cites Diédhiou et al. 2008 sourcePartly supported

  The Background (page not provided) says MAPKs are involved in osmotic-stress signaling in tobacco and Arabidopsis, and that protein kinases participate in signal transduction in eukaryotes. It does not establish that MAPKs respond to heat shock, mitogens, or proinflammatory cytokines, or that MAPKs convey information from sensors to cellular processes in all eukaryotes. (LLM, conf=0.86)

  Experimental — accuracy not yet measured
• cites Inagaki et al. 2008 sourcePartly supported

  The Results and Discussion (page not provided) show that osmotic stress activates the MAPK JNK in mouse embryonic fibroblasts. The opening section also links cytokine signaling to MAPKs. Our copy does not establish MAPK responses to heat shock or mitogens, or the claim that MAPKs relay information from sensors to cellular processes in all eukaryotes. (LLM, conf=0.86)

  Experimental — accuracy not yet measured

Probably not a substantial claim: may not pass S3 (load-bearing).

Transgenic C3 plants overexpressing multiple C4 enzymes are now in the focus of most scientists to improve photosynthetic capacity in C3 plants.

“However, transgenic C 3 plants overexpressing multiple C 4 enzymes are now in the focus of most scientists to improve photosynthetic capacity in C 3 plants (Miyao 2003, Begonia and Begonia 2007, Kajala et al. 2012).”

• cites Miyao 2003 sourceNot checked — no full text of the source
• cites Begonia and Begonia 2007 sourcePartly supported

  The Leaf function section describes transgenic rice with enhanced activity of the C4 enzyme PEPC and enhanced leaf photosynthesis, calling this work “at the cutting edge of photosynthesis research.” It does not establish that the plants overexpressed multiple C4 enzymes or that they were the focus of most scientists. Page numbers are unavailable in our copy. (LLM, conf=0.86)

  Experimental — accuracy not yet measured
• cites Kajala et al. 2012 sourcePartly supported

  The Abstract (page unavailable) says C4 photosynthesis permits higher photosynthetic rates than the ancestral C3 pathway, supporting the rationale for seeking an improvement. It does not say that transgenic C3 plants overexpressing multiple C4 enzymes are a focus of most scientists; the paper instead examines regulation of C4-related genes. (LLM, conf=0.78)

  Experimental — accuracy not yet measured

May combine two claims.

In most published studies on transgenic lines made for enhanced photosynthetic performance, a single C4 enzyme gene has been transferred, but in most cases this did not result in a major success in terms of enhanced photosynthetic capacity in transgenic C3 lines.

“In most of the studies on generations of transgenic lines made for enhanced photosynthetic performance that were published so far, a single C 4 enzyme gene has been transferred, but in most cases this did not result in a major success in terms of enhanced photosynthetic capacity in transgenic C 3 lines.”

Probably not a substantial claim: may not pass S4 (based).

There is little information on the components involved in either the perception or signaling involved in stress responses.

“There is little information on the components involved in either the perception or signaling involved in stress responses.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Our knowledge of the signaling pathways has increased greatly over recent years by integrating advances in molecular genetics and cell biology, although it is still far from a full understanding of perception and signaling of environmental cues in plants.

“Undoubtedly, by integrating the advances in molecular genetics and cell biology, our knowledge of the signaling pathways has increased greatly over recent years, although it is still far from a full understanding to perception and signaling of environmental cues in plants.”

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

Efforts are currently underway in different laboratories all over the world to identify signaling components, such as transcription factors and protein kinases, particularly MAPKs, involved in stress adaptation in plants.

“Efforts get currently underway in different laboratories all over the world to identify signaling components, such as transcription factors and protein kinases, particularly MAPKs, involved in stress adaptation in plants.”

May combine two claims.

The chloroplast is highly sensitive to stressful environments such as salinity, drought, extremes of temperature, flooding, varying light intensity, and UV radiation, and plays a premier role in modulation of stress responses.

“However, this organelle is highly sensitive to different stressful environments such as salinity, drought, extremes of temperature, flooding, varying light intensity, and UV radiation, and it plays a premier role in the modulation of stress responses (Biswal et al. 2008, Saravanavel et al. 2011).”

• cites Biswal et al. 2008 sourceNot checked — no full text of the source
• cites Saravanavel et al. 2011Not checked — no full text of the source

May combine two claims.

High concentrations of Na+ and Cl- accumulating in chloroplasts under salinity stress damage thylakoid membranes; high concentrations of inorganic salts swiftly and irrevocably inactivate electron transport and photophosphorylation of isolated thylakoid membranes.

“High concentrations of injurious ions, such as Na + and Cl -, which accumulate in the chloroplasts under salinity stress, are known to damage thylakoid membranes (Wu andZou 2009, Omoto et al. 2010).Electron transport and photophosphorylation of isolated thylakoid membranes were reported to be swiftly and irrevocably inactivated by high concentrations of inorganic salts (Veiga andSilva 2007, Mittal”

• cites Wu andZou 2009Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Omoto et al. 2010 sourceNot checked — no full text of the source
• cites Veiga andSilva 2007Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Under severe drought stress, dehydration of mesophyll cells causes marked inhibition of basic metabolic processes of photosynthesis and reduction of plant WUE.

“However, in contrast, under severe drought stress, dehydration of mesophyll cells takes place causing a marked inhibition of basic metabolic processes of photosynthesis as well as a reduction of plant WUE (Damayanthi et al. 2010, Anjum et al. 2011).”

• cites Damayanthi et al. 2010Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Anjum et al. 2011Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Stressful environments such as salinity, drought, and high temperature cause alterations in physiological, biochemical, and molecular processes in plants and severely affect photosynthesis in all its phases.

“Stressful environments such as salinity, drought, and high temperature (heat) cause alterations in a wide range of physiological, biochemical, and molecular processes in plants.Photosynthesis, the most fundamental and intricate physiological process in all green plants, is also severely affected in all its phases by such stresses.”

May combine two claims.

Salt stress can break down chlorophyll, an effect ascribed to increased Na+, and reduces Chl a and b in crops such as sunflower, alfalfa, wheat, and castor bean.

“For example, salt stress can break down chlorophyll (Chl), the effect ascribed to increased level of the toxic cation, Na + (Pinheiro et al. 2008, Li et al. 2010, Yang et al. 2011).Reduction in photosynthetic pigments, such as Chl a and b has been reported in some earlier studies on different crops, e.g., sunflower, Heliantus annuus (Ashraf andSultana 2000, Akram andAshraf 2011), alfalfa, Medicago”

• cites Pinheiro et al. 2008 sourceNot checked — no full text of the source
• cites Li et al. 2010Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Yang et al. 2011 sourceNot checked — no full text of the source

May combine two claims.

Drought stress decreases PSII proteins D1, D2, LHCII and mRNAs of psbA, psbD, cab; phosphorylation and dephosphorylation of PSII proteins regulate PSII repair, and water stress causes rapid dephosphorylation of PSII proteins in barley.

“The amounts of PSII proteins, such as D1, D2, and LHCII as well as mRNA corresponding to genes of psbA, psbD, and cab, also declined markedly due to water deficit; this was ascribed to decreased rates of transcription and translation as well as fast deterioration of proteins and mRNAs (Duan et al. 2006, Liu et al. 2009).”

• Also stated in: § Stress-induced changes · plain

  “Phosphorylation and dephosphorylation of PSII are the main regulatory factors and they play a major role in PSII repair.”

• Also stated in: § Stress-induced changes · boosted

  “Liu et al. (2009) have shown that water stress caused the rapid dephosphorylation of PSII proteins, coupled with the phosphorylation of LHCII b4 and CP29, in barley (Hordeum vulgare).”

• cites Duan et al. 2006Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Liu et al. 2009Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Photosynthesis shows a reversible decline under mild temperature stress and permanent impairment after severe heat stress; at high temperatures PSII and stroma become oxidized and PSI is significantly reduced.

“Photosynthesis is sensitive to changes in temperature, but a reversible decline has been observed under mild temperature stress, while a permanent impairment was found after an exposure to severe heat stress.”

• Also stated in: § Stress-induced changes · plain

  “At high temperatures, PSII and stroma become oxidized and a significant reduction takes place in PSI.”

May combine two claims.

PSII is a prominent heat-sensitive component of photosynthesis but can function normally up to 45°C; moderately high temperature (35-45°C) can induce cyclic electron transport and make thylakoid membranes leaky; Rubisco deactivation at mild heat is attributed to heat effects on chloroplast reactions.

“PSII has been long believed to be a prominent heat sensitive component of photosynthesis (Schrader et al. 2004), but it can perform normal functioning up to 45°C (Gombos et al. 1994).”

• Also stated in: § Stress-induced changes · hedged

  “However, there are some reports showing that moderately high temperature (35-45°C) can induce the cyclic transport of electrons and thylakoid membranes become leaky (Sharkey 2005).”

• Also stated in: § Stress-induced changes · hedged

  “The deactivation of Rubisco at mild heat stress could be attributed to the deleterious effects of heat on chloroplast reactions (Sharkey 2005, Velikova et al. 2012).”

• cites Schrader et al. 2004 sourceNot checked — no full text of the source
• cites Gombos et al. 1994 sourceNot checked — no full text of the source
• cites Sharkey 2005 sourceNot checked — no full text of the source

May combine two claims.

Changes in thylakoid membrane ultrastructure above 40°C cause dissociation of LHCII Chl a/b-proteins from the PSII core complex, leading to destacking of granum membranes; phosphorylation and dephosphorylation of thylakoid proteins play a critical role in plant responses to elevated temperature.

“From a number of studies, it is evident that changes occurring in the ultrastructure of thylakoid membranes above 40°C cause dissociation of the LHCII Chl a/b-proteins from the PSII core complex (Tang et al. 2007, Iwai et al. 2010).”

• Also stated in: § Stress-induced changes · plain

  “However, heat-induced alteration in these proteins leads to destacking of the appressed membranes of the granum (Fristedt et al. 2009, Lemeille andRochaix 2010), which is mediated by the separation of nonbilayer-forming lipids.”

• Also stated in: § Stress-induced changes · hedged

  “As in the case of drought stress, phosphorylation and dephosphorylation of thylakoid proteins has been suggested to play a critical role in responses of plants to elevated temperature (Krishnan andPueppke 1987, Conde et al. 2011).”

• cites Tang et al. 2007 sourceNot checked — no full text of the source
• cites Iwai et al. 2010 sourceNot checked — no full text of the source
• cites Fristedt et al. 2009Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Carotenoids protect photosynthesis and membranes from oxidative damage; salt stress reduces Chl and Car contents, and Car content may be a selection criterion for salt tolerance; high temperature reduces the Chl/Car ratio in wheat.

“Carotenoids (Car) are necessary for photoprotection of photosynthesis and they play an important role as a precursor in signaling during the plant development under abiotic/biotic stress.”

• Also stated in: § Stress-induced changes · plain

  “Recently, working with sugar cane, Gomathi and Rakkiyapan (2011) found that imposition of salt stress (7-8 dS m -1 ) at various plant growth stages caused a marked reduction in Chl and Car contents, but salt-tolerant varieties exhibited higher membrane stability and pigment contents.”

• Also stated in: § Stress-induced changes · plain

  “A considerable reduction (about 52%) in Chl/Car ratio was reported in wheat plants under high-temperature stress (Yildiz and Terzi 2008).”

• cites Gomathi and Rakkiyapan (2011) sourceNot checked — no full text of the source
• cites Yildiz and Terzi 2008Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims. The quote only partly states this claim.

Drought stress damages the oxygen-evolving center and D1 polypeptide, inactivating the PSII reaction center; this leads to ROS generation, photoinhibition, and oxidative damage.

“A number of studies conducted in vivo have shown that drought stress causes considerable damage to the oxygen evolving center (OEC) coupled with PSII (Skotnica et al. 2000, Kawakami et al. 2009) as well as degradation of D1 polypeptide leading to the inactivation of the PSII reaction center (He et al. 1995, Liu et al. 2006, Zlatev 2009).”

• Also stated in: § Stress-induced changes · plain

  “The changes lead to the generation of reactive oxygen species (ROS), which ultimately cause the photoinhibition and oxidative damage (Ashraf 2009, Gill and Tuteja 2010, Anjum et al. 2011).”

• cites Skotnica et al. 2000 sourceNot checked — no full text of the source
• cites He et al. 1995Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Ashraf 2009 sourceNot checked — no full text of the source

May combine two claims.

The salinity-induced osmotic effect causes substantial accumulation of ABA, particularly in guard cells, leading to partial stomata closure and lowered stomatal conductance and substomatal CO2 concentration.

“The salinity-induced osmotic effect on plants causes a substantial accumulation of abscisic acid (ABA), particularly in the guard cells of stomata, which consequently leads to a partial stomata closure thereby lowering the stomatal conductance as well as substomatal CO 2 concentration (Zhao et al. 2009b).”

• cites Zhao et al. 2009bNot matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

The xanthophyll cycle, particularly de-epoxidation of violaxanthin to zeaxanthin through antheraxanthin, plays an important role in photoprotection and energy dissipation at high light intensity; NPQ correlates with zeaxanthin and antheraxanthin contents.

“The xanthophyll cycle, particularly the de-epoxidation of violaxanthin to zeaxanthin through antheraxanthin, was reported to play an important role in energy dissipation at high light intensity (Demmig-Adams and Adams 1992, Misra et al. 2006).”

• Also stated in: § Stress-induced changes · plain

  “The dissipation of excitation energy is determined as nonphotochemical quenching (NPQ) of Chl fluorescence during photosynthetic electron transport, which significantly correlates with contents of zeaxanthin and antheraxanthin produced during the xanthophyll cycle (Niyogi et al. 1997).”

• cites Demmig-Adams and Adams 1992 sourceNot checked — no full text of the source
• cites Misra et al. 2006 sourceNot checked — no full text of the source
• cites Niyogi et al. 1997 sourceNot checked — no full text of the source

May combine two claims. The quote only partly states this claim.

Under saline treatments, kidney bean seedlings show increased de-epoxidation of violaxanthin and increased NPQ, unlike cabbage, which may shield pigment-protein complexes from salt-induced photodamage.

“Although the photochemical efficiency of PSII was similar in both cabbage and kidney bean seedlings, the de-epoxidation state of violaxanthin increased six-fold in kidney bean, while no significant change was observed in cabbage under saline treatments.Similarly, NPQ increased in kidney bean, but decreased in cabbage.”

• Also stated in: § Stress-induced changes · hedged

  “Thus, the increase in the de-epoxidation state of violaxanthin in salt-stressed kidney plants may be a signal to shield the pigment-protein complexes from salt-induced photodamage (Misra et al. 2006).”

• cites Misra et al. 2006 sourceNot checked — no full text of the source

May combine two claims.

Photosynthetic pigments in photosystems are damaged by stress factors, reducing light-absorbing efficiency of both PSI and PSII and hence photosynthetic capacity.

“Photosynthetic pigments present in the photosystems are believed to be damaged by stress factors resulting in a reduced light-absorbing efficiency of both photosystems (PSI and PSII) and hence a reduced photosynthetic capacity (Geissler et al. 2009, Zhang et al. 2011).”

• cites Geissler et al. 2009Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Zhang et al. 2011 sourceNot checked — no full text of the source

May combine two claims.

Drought stress damages photosynthetic pigments and thylakoid membranes; decrease in Chl content is commonly observed under drought, but some reports show no significant effect or enhanced Chl accumulation; under drought, Chl b decreases more than Chl a, shifting the ratio in favor of Chl a.

“As salinity stress, drought stress causes not only a substantial damage to photosynthetic pigments, but it also leads to deterioration of thylakoid membranes (Huseynova et al. 2009, Anjum et al. 2011, Kannan and Kulandaivelu 2011).”

• Also stated in: § Stress-induced changes · plain

  “The decrease in Chl content is a commonly observed phenomenon under drought stress (Bijanzadeh and Emam 2010, Mafakheri et al. 2010, Din et al. 2011).”

• Also stated in: § Stress-induced changes · boosted

  “It is generally known that under drought stress the reduction of Chl b is greater than that of Chl a, thus, transforming the ratio in favor of Chl a (Jaleel et al. 2009, Jain et al. 2010).”

• cites Huseynova et al. 2009 sourceNot checked — no full text of the source
• cites Anjum et al. 2011Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Kannan and Kulandaivelu 2011Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Salinity effects on PSII are contradictory: some studies show significant inhibition of PSII activity, while others find no significant effect on PSII structure and function; salt-induced damage to PSII can be reversible.

“For example, some studies have shown a significant inhibitory effect of salinity on PSII activity (Everard et al. 1994, Akram and Ashraf 2011, Saleem et al. 2011), whereas other reports found no significant effect on the structure and function of PSII (Al-Taweel et al. 2007, Abdeshahian et al. 2010).”

• Also stated in: § Stress-induced changes · plain

  “Recently, Mehta et al. (2010) have reported that the donor side of the PSII was damaged more than the acceptor side due to salt stress (0.1-0.5 M NaCl) in wheat (Triticum aestivum).”

• Also stated in: § Stress-induced changes · plain

  “Furthermore, the salt-induced damage to PSII was reversible, because 100% recovery of the acceptor side and about 85% of the donor side has been reported (Mehta et al. 2010).”

• cites Everard et al. 1994 sourceNot checked — no full text of the source
• cites Al-Taweel et al. 2007 sourceNot checked — no full text of the source
• cites Mehta et al. 2010 sourceNot checked — no full text of the source

May combine two claims.

CO2-exchange characteristics are an important indicator of plant growth because of their direct link to net productivity; the effect of any stress on photosynthesis can be stomatal, nonstomatal, or both, and the extent depends on species.

“CO 2 -exchange characteristics have been regarded an important indicator of the growth of plants, because of their direct link to net productivity (Ashraf 2004, Piao et al. 2008).”

• Also stated in: § Stress-induced changes · hedged

  “However, the effect of any stress on photosynthesis could be caused by stomatal, nonstomatal or both factors (Athar andAshraf 2005, Saibo et al. 2009), nevertheless, the extent of stress-induced stomatal or nonstomatal regulation depends on the species.”

• cites Ashraf 2004 sourceNot checked — no full text of the source
• cites Piao et al. 2008 sourceNot checked — no full text of the source
• cites Athar andAshraf 2005Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Chl fluorescence measurement is convenient and noninvasive and gives insight into excitation energy exploitation by PSII and indirectly other thylakoid protein complexes, particularly under stress.

“Despite the fact that the extent of Chl fluorescence does not comprise more than 1-2% of total light absorbed by the Chl, its measurement is convenient and noninvasive.It gives a valuable insight into exploitation of the excitation energy by PSII, and indirectly by the other protein complexes of the thylakoid membranes (Walker 1987, Roháček 2002), particularly in plants exposed to stressful”

• cites Walker 1987Not checked — no full text of the source
• cites Roháček 2002 sourceNot checked — no full text of the source

May combine two claims.

Drought, salinity, and high-temperature stress impair the functionality of both photosystems and reduce electron transport through them, lowering production of ATP and NADPH and ultimately limiting CO2 reduction.

“It is evident that drought, salinity, and high-temperature stress adversely affect the functionality of both photosystems and reduce electron transport through them.”

• Also stated in: § Stress-induced changes · plain

  “This results in a low production of ATP and NADPH, the two main products of the light reactions (electron transport), which are essential for CO 2 fixation in the dark reactions of the photosynthesis.”

• Also stated in: § Stress-induced changes · plain

  “Thus, stress-induced impairment of the photosystems ultimately limits the CO 2 reduction process.”

May combine two claims.

A relationship of gs with leaf water potential or RWC was not observed; reduced photosynthesis caused by water deficit occurred at different leaf water levels in different species even at similar gs.

“However, a relationship of g s with leaf water potential or RWC was not observed, i.e., reduced photosynthesis caused by water-deficit conditions occurred at different leaf water levels in different species, even though at similar g s (Athar andAshraf 2005, Peri et al. 2009).”

• cites Athar andAshraf 2005Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Peri et al. 2009 sourceNot checked — no full text of the source

May combine two claims.

PEPC isolated from wheat (C3) and maize (C4) was inhibited under saline regimes, but the enzyme from wheat was less sensitive to salt than that from maize.

“Abdel-Latif (2008) observed that although the activities of phosphoenolpyruvate carboxylase (PEPC) isolated from wheat (C 3 plant) and that from maize (C 4 plant) were inhibited under saline regimes, the enzyme from wheat was less sensitive to salt than that from maize (Table 2).”

• cites Abdel-Latif 2008Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Photosynthetic capacity has been considered a potential indicator of heat-stress tolerance in different plant species because gas-exchange characteristics showed a positive association with drought tolerance in tomato and melon.

“Photosynthetic capacity (rate of photosynthesis) has also been considered as one of the potential indicators of heat-stress tolerance in different plant species, because the gas-exchange characteristic showed a positive association with the drought tolerance in different species or cultivars within the species in several studies, e.g., tomato (Camejo et al. 2005, Singh et al. 2005) and melon (Kit”

• cites Camejo et al. 2005 sourceNot checked — no full text of the source
• cites Singh et al. 2005 sourceNot checked — no full text of the source
• cites Kitroongruang et al. 1992 sourceNot checked — no full text of the source

May combine two claims.

The positive relationship of photosynthetic capacity to drought tolerance is not a general rule; other studies obtained reverse results.

“However, such a positive relationship of photosynthetic capacity to drought tolerance is not a general rule and in other studies the reverse results were obtained.”

May combine two claims.

A potato transgenic line expressing chloroplastic fructose-1,6-bisphosphatase at less than 15% of wild-type showed considerably reduced PN and growth, indicating the enzyme has a key role in regulation of the Calvin cycle.

“Similarly, in another study with potato, a transgenic line expressing the chloroplastic fructose-1,6-bisphosphatase at less than 15% compared with the wild-type plants showed considerably reduced P N and growth; it shows that the enzyme has a key role in the regulation of the Calvin cycle (Kossman et al. 1994).”

• cites Kossman et al. 1994Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

It is likely that either water deficit has no effect on photosynthesis until a threshold is reached, beyond which it is impaired, or a consistent suppression in metabolism is caused.

“Thus, it is likely that either water deficit has no effect on photosynthesis until a threshold is reached, beyond which it is impaired or a consistent suppression in metabolism is caused (Lawlor 2002, Athar and Ashraf 2005, Lawlor and Tezara 2009).”

• cites Lawlor 2002Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Athar and Ashraf 2005Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Lawlor and Tezara 2009 sourceNot checked — no full text of the source

May combine two claims.

Leaves that survive drought often show higher rates of photosynthesis and of Rubisco content per unit leaf area.

“It has also been shown that leaves that survive drought often show higher rates of photosynthesis (Ludlow and Ng 1974, Akram et al. 2007, Bayramov et al. 2010) and of Rubisco content per unit leaf area (David et al. 1998, Kumar andSingh 2009).”

• cites Ludlow and Ng 1974 sourceNot checked — no full text of the source
• cites Akram et al. 2007Not checked — no full text of the source
• cites Bayramov et al. 2010 sourceNot checked — no full text of the source

May combine two claims.

Salt stress regulates not only Rubisco but also enzymes involved in regeneration of RuBP, which can play a key role in regulation of the Calvin cycle.

“In another study with two species of rice, Ghosh et al. (2001) found that not only Rubisco is affected, but also the enzymes involved in regeneration of the Rubisco substrate, ribulose-1,5-bisphophate (RuBP) are regulated by salt stress and they can play a key role in the regulation of the Calvin cycle (Table 2).”

• cites Ghosh et al. 2001 sourceNot checked — no full text of the source

May combine two claims.

In subterranean clover, water deficit reduced initial and total Rubisco activity but did not decrease the overall amount of Rubisco protein per unit leaf area.

“For example, in subterranean clover (Trifolium subterraneum), water deficit conditions reduced the initial and total Rubisco activity, but it did not decrease the overall amount of Rubisco protein per unit of leaf area (Medrano et al. 1997).”

• cites Medrano et al. 1997 sourceNot checked — no full text of the source

May combine two claims.

PEPCase from the C4 plant Amaranthus hypochondriacus was less sensitive to supraoptimal temperature but more sensitive to suboptimal temperature than the enzyme from the C3 species Pisum sativum.

“Chinthapalli et al. (2003) showed that the PEPCase from the C 4 plant (Amaranthus hypochondriacus) was less sensitive to supraoptimal temperature, but more sensitive to suboptimal temperature than the enzyme from the C 3 species (Pisum sativum).”

• cites Chinthapalli et al. 2003Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

Overexpression of chloroplastic glutamine synthetase significantly reduced tissue Na+ content under saline regimes, suggesting a putative role of this enzyme in salt tolerance of rice.

“They showed that the overexpression of glutamine synthetase significantly reduced the tissue Na + content under saline regimes, suggesting the putative role of this enzyme in salt tolerance of rice.”

• cites Tanaka et al. 2005 sourceNot checked — no full text of the source

May combine two claims.

A maize line with enhanced expression of C4-PEPC showed a 30% increase in WUE and a 20% increase in dry biomass under moderate water-deficit conditions.

“This transgenic line showed a 30% increase in WUE and a 20% increase in dry biomass under moderate waterdeficit conditions.”

• cites Jeanneau et al. 2002 sourceNot checked — no full text of the source

May combine two claims.

Two approaches are currently used to improve photosynthetic capacity in different plant species: developing transgenic C3 plants with over-expression of Rubisco genes or other enzymes of the C3 pathway, and transferring the genes of a key C4 photosynthetic pathway to C3 plants.

“Two approaches are currently used to improve the photosynthetic capacity in different plant species.Firstly, an effort is devoted to developing transgenic C 3 plants with over-expression of Rubisco genes or other enzymes of the C 3 pathway.Secondly, attempts are underway to transfer the genes of a key C 4 photosynthetic pathway to C 3 plants (Table 3).”

May combine two claims.

A number of enzymes of both CO2 concentrating mechanisms are regulated by light, so light intensity and duration in addition to the intensity of additional stress play a significant role in the regulation of these enzymes.

“Furthermore, a number of enzymes of both CO 2 concentrating mechanisms are regulated by light (Taiz andZeiger 2010, Doubnerová andRyšlavá 2011), so the light intensity and its duration in addition to the intensity of additional stress play also a significant role in the regulation of these enzymes.”

• cites Taiz andZeiger 2010Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

• cites Doubnerová andRyšlavá 2011Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

In wheat, heat stress imposed for 12 days caused a sharp decline in Rubisco activity, whereas PEPC activity increased first but later decreased, causing a marked increase in the PEPC/Rubisco ratio.

“For example, in wheat (Triticum aestivum), heat stress imposed for 12 days caused a sharp decline in Rubisco activity, whereas the activity of PEPC increased first, but later decreased, which caused a marked increase in PEPC/Rubisco ratio (Xu et al. 2003).”

• cites Xu et al. 2003Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Classified as probably not a substantial claim.

The enhanced rate of photosynthesis under salt stress in the OsSbp transgenic rice might have been due to enhanced supply of RuBP to Rubisco by activation of SBPase.

“They suggested that the enhanced rate of photosynthesis under salt stress might have been due to the enhanced supply of RuBP to Rubisco by the activation of SBPase.”

• cites Feng et al. 2007 sourceNot checked — no full text of the source

May combine two claims.

The activities of various C4 photosynthesis enzymes decreased 2 to 4 times under drought, whereas PPDK activity declined 9.1 times in C4 sugarcane.

“In another study concerning nonstomatal limitations of photosynthesis, Du et al. (1998) reported that the activities of the various C 4 photosynthesis enzymes, such as PEPcase, NADPmalic enzyme (NADP-ME), Rubisco, and fructose-1,6bisphosphatase, decreased 2 to 4 times under drought conditions, whereas the activity of phosphopyruvate dikinase (PPDK) declined 9.1 times in C 4 plant, sugar cane.”

• cites Du et al. 1998Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based).

Under most stresses the balance between different enzymes is also perturbed.

“It has also been observed that under most stresses the balance between different enzymes is also perturbed.”

May combine two claims.

A 68% decrease in Rubisco activity did not hamper PN under water-limited regimes, suggesting drought stress may affect steps involved in RuBP regeneration rather than Rubisco itself.

“They showed that a 68% decrease in Rubisco activity did not hamper P N under water-limited regimes, suggesting that drought stress may affect any of the steps involved in the regeneration of RuBP rather than Rubisco itself.”

• cites Gunasekera and Berkowitz 1993 sourceNot checked — no full text of the source

May combine two claims.

Rubisco activity in Setaria sphacelota declined slightly under moderate drought but substantially under severe drought.

“In another study, Marques and Arrabica (1995) found that Rubisco activity in Setaria sphacelota declined slightly under moderate drought, but substantially under severe drought.”

• cites Marques and Arrabica 1995Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

May combine two claims.

A transgenic japonica rice line overexpressing OsSbp cDNA from an indica rice cultivar showed enhanced SBPase activity, enhanced photosynthetic capacity, and increased tolerance to salt stress.

“Using the first strategy, Feng et al. (2007) produced a transgenic line of japonica rice by overexpressing OsSbp cDNA from an indica rice cultivar.This transgenic line showed beside an enhanced activity of the C 3 enzyme sedoheptulose-l,7-bisphosphatase (SBPase, EC 3.1.3.37), which is involved in the regeneration of RuBP, also the enhanced photosynthetic capacity as well as the increased tolerance”

• cites Feng et al. 2007 sourceNot checked — no full text of the source

Classified as probably not a substantial claim.

The extent to which C4 enzymes transferred to C3 plants take part in effective assimilation of CO2 in C3 engineered plants depends on a multitude of factors, including the partitioning of introduced C4 enzymes within the leaf tissues and the interlinking of C4 enzymes with photosynthesis-related pathways functioning in C3 plants.

“It depends undoubtedly on a multitude of factors including the partitioning of introduced C 4 enzymes within the leaf tissues and the interlinking of C 4 enzymes with photosynthesis-related pathways functioning in C 3 plants.”

May combine two claims.

Although overexpression of a single C4 enzyme can modulate photosynthetic metabolism in C3 plants, in most cases it does not have significant effects on photosynthesis.

“It has been observed that although overexpression of a single C 4 enzyme can modulate the photosynthetic metabolism in C 3 plants, in most cases, it does not have significant effects on photosynthesis.”

Classified as probably not a substantial claim.

Photosynthetic response to different types of stresses is intricate because it entails the interaction of several restrictions occurring at different locations of the cell or the leaf, and at different phases of the plant growth and development.

“Photosynthetic response to different types of stresses is quite intricate, because it entails the interaction of several restrictions occurring at different locations of the cell or the leaf, and at different phases of the plant growth and development.”

May combine two claims.

The enhanced drought tolerance of the NPK1 transgenic maize line was strongly associated with a markedly high rate of photosynthesis, suggesting an active role of NPK1 in protecting the photosynthetic machinery from water stress damage.

“The enhanced drought tolerance of the transgenic line of maize was shown to be strongly associated with a markedly high rate of photosynthesis, suggesting the active role of NPK1 in the mechanism of protection of photosynthesis machinery from water stress damage.”

• cites Shou et al. 2004Not matched

  Couldn’t be matched to a paper in Crossref, so it can’t be checked.

Probably not a substantial claim: may not pass S3 (load-bearing).

MAPKs regulate a multitude of cellular processes, such as mitosis, differentiation, gene expression, and cell death or survival.

“They are known to regulate a multitude of cellular processes, such as mitosis, differentiation, gene expression, and cell death or survival (Zhang and Klessig 2001).”

• cites Zhang and Klessig 2001 sourceNot checked — no full text of the source

Classified as probably not a substantial claim.

It is not clear yet to what extent C4 enzymes transferred to C3 plants take part in effective assimilation of CO2 in C3 engineered plants.

“It is not clear yet up to what extent C 4 enzymes transferred to C 3 plants take part in effective assimilation of CO 2 in C 3 engineered plants.”

Probably not a substantial claim: may not pass S4 (based).

It is not easy to discriminate between the effects of stomatal and nonstomatal limitations on overall photosynthetic capacity of a plant.

“However, it is not easy to discriminate between the effects of these limitations on overall photosynthetic capacity of a plant.”