Light Energy Use Efficiency in Photosystem II of Tomato Is Related to Leaf Age and Light Intensity
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors1. There is an excess of abbreviations throughout the manuscript, and although they are described the first time mentioned (also in supplementary information), they disrupt the fluency of reading. For the benefit of readers, it is suggested to write the full terms as far as possible. Only those of more widespread use should remain (e.g. PSII, ROS).
2. End of the introduction (lines 106-111). It is suggested to develop a wording that clearly indicates the objectives of the study, in addition to the hypothesis already written.
3. Materials and Methods (line 131). The authors indicate that they performed a two-way analysis of variance. Please indicate the factors and levels involved in this analysis.
4. It is strongly suggested to include the analysis of variance table and pay special attention to the interaction component age of the leaf x light intensity, as there appear that statistically significant differences exist for the parameters ΦPSII,ΦNPQ, ΦNO and Fv’/Fm’ between tomato leaf ages ONLY under low light intensity, not so under high light intensity. Perhaps by carefully analysing the ANOVA results, the course of the discussion could be modified.
Author Response
Comments and Suggestions for Authors
Dear Reviewer,
We would like to thank you for dedicating the time and the effort to review our work and for the valuable comments and suggestions that we adopted in our revised manuscript.
- There is an excess of abbreviations throughout the manuscript, and although they are described the first time mentioned (also in supplementary information), they disrupt the fluency of reading. For the benefit of readers, it is suggested to write the full terms as far as possible. Only those of more widespread use should remain (e.g. PSII, ROS).
Answer: We fully agree with your comment. Too many abbreviations disrupt the fluency of reading. However, we used abbreviations since the full terms are three words and more and when MDPI journals perform plagiarism check all the terms are marked as “plagiarism” increasing the percentage to high levels.
- End of the introduction (lines 106-111). It is suggested to develop a wording that clearly indicates the objectives of the study, in addition to the hypothesis already written.
Answer: We included such a sentence taking into account your suggestion.
- Materials and Methods (line 131). The authors indicate that they performed a two-way analysis of variance. Please indicate the factors and levels involved in this analysis.
Answer: The following text was included “A two-way ANOVA was performed for each parameter with Leaf Age (young or mature), and Light Intensity (426 μmol photons m−2 s−1 or 1000 μmol photons m−2 s−1), as factors, followed by post hoc analysis with Tukey’s honest significant difference method with the R package ‘multcomp’.”
- It is strongly suggested to include the analysis of variance table and pay special attention to the interaction component age of the leaf x light intensity, as there appear that statistically significant differences exist for the parameters ΦPSII,ΦNPQ, ΦNO and Fv’/Fm’ between tomato leaf ages ONLY under low light intensity, not so under high light intensity. Perhaps by carefully analysing the ANOVA results, the course of the discussion could be modified.
Answer: We appreciate your suggestion to include ANOVA table and discuss it comprehensively. Thank you for your valuable comment regarding the analysis of variance (ANOVA) tables. We included as Supplementary Table S2 the analysis of variance for the parameters ΦPSII,ΦNPQ, ΦNO and Fv’/Fm’ and the conclusions were added in the Results and Discussion sections. Thank you again for your constructive comments.
Reviewer 2 Report
Comments and Suggestions for AuthorsThe article „Light energy use efficiency in photosystem II of tomato is related to leaf age and light intensity“ reports the photosynthetic performance and photoprotective mechanisms of developing leaves and mature leaves. This topic is very important in the context of differential photosynthesis performance at different developmental stages and under different light intensities.
I recommend this article be published with minor improvements.
The main comment: In the M&M section, the authors should specify the growth stage according to the accepted scale (e.g., the BBCH scale). Mature leaves can be studied at vegetative and reproductive stages, and the pattern can differ. Moreover, the position of selected leaves (relatively stem) and leaflets (terminal, primary, compound…) for the analysis should be specified as well. The position of a leaf may impact the efficiency of photosynthesis.
There are a lot of abbreviations in the article and their deciphering is repeated multiple times. Examples: NPQ in lines 48 and 64, EXC in lines 282 and 305.
Table S1: I suggest putting this table as Table 1 in the main text of the M&M section. It will be very helpful while reading the article, especially to avoid confusing all the abbreviations.
Figure 1: For measuring these parameters, plants were kept in the dark for some time. But what light intensity was initially? Why were these parameters not measured after both LLI and HLI?
Figure 6. Could you please discuss in the text why the second part of Fv/Fm is blank?
Conclusion: It would be very beneficial if the authors could extend the conclusion a bit more, specifying if the last sentence is relevant to both LLI and HLI treatment.
Comments on the Quality of English LanguageThe authors should revise the text for typos. Examples: line 30 “conclud”, line 122 “contacted”
Author Response
Comments and Suggestions for Authors
The article „Light energy use efficiency in photosystem II of tomato is related to leaf age and light intensity“ reports the photosynthetic performance and photoprotective mechanisms of developing leaves and mature leaves. This topic is very important in the context of differential photosynthesis performance at different developmental stages and under different light intensities.
I recommend this article be published with minor improvements.
Dear Reviewer,
We would like to thank you for dedicating the time and the effort to review our work and for the valuable comments and suggestions that we adopted in our revised manuscript
The main comment: In the M&M section, the authors should specify the growth stage according to the accepted scale (e.g., the BBCH scale). Mature leaves can be studied at vegetative and reproductive stages, and the pattern can differ. Moreover, the position of selected leaves (relatively stem) and leaflets (terminal, primary, compound…) for the analysis should be specified as well. The position of a leaf may impact the efficiency of photosynthesis.
Answer: Τhe growth stage according to the BBCH scale was included and a supplemental Figure was provided showing the position of the selected leaves (Figure S1.)
There are a lot of abbreviations in the article and their deciphering is repeated multiple times. Examples: NPQ in lines 48 and 64, EXC in lines 282 and 305.
Answer: Yes, there are a lot of abbreviations in the article and their deciphering is repeated multiple times. We eliminated some of them, and kept for example the full terms of e.g., oxygen-evolving complex, higher effective quantum yield, and reduced excess excitation energy in the “Conclusion” section for a more fluent reading.
Table S1: I suggest putting this table as Table 1 in the main text of the M&M section. It will be very helpful while reading the article, especially to avoid confusing all the abbreviations.
Answer: We fully agree with your comment. Table S1 would have been better included as Table 1 in the main text of the M&M section. However, we included it as Table S1 because all terms are three words and more and when MDPI journals perform plagiarism check all the terms are marked as “plagiarism” increasing the percentage to high levels. This is also the reason why we used a lot of abbreviations in the article.
Figure 1: For measuring these parameters, plants were kept in the dark for some time. But what light intensity was initially? Why were these parameters not measured after both LLI and HLI?
Answer: The two parameters Fv/Fo and Fv/Fm are measured after 30 min dark adaptation of the leaves, in order all the reactions centers to be open. Before dark adaptation the light intensity was 420 ± 10 μmol quanta m−2 s−1, that is the light intensity of the growth chamber. If we wanted to measure them after LLI and HLI we would have to dark adapt the leaves again for 30 min in order all the reactions centers to be open, thus the difference of AL intensity (LLI or HLI) would have no impact on these parameters.
Figure 6. Could you please discuss in the text why the second part of Fv/Fm is blank?
Answer: The second part of Fv/Fm is blank since Fv/Fm is measured only after dark adaptation, as it is mentioned at the subheading in Figure 6.
Conclusion: It would be very beneficial if the authors could extend the conclusion a bit more, specifying if the last sentence is relevant to both LLI and HLI treatment.
Answer: Yes, you are right. It was missing in the conclusion that at the HLI results were different from the LLI. We added it.
Comments on the Quality of English Language
The authors should revise the text for typos. Examples: line 30 “conclud”, line 122 “contacted”.
Answer: Thank you for pointing out these mistakes. We corrected them in our revised manuscript and check for any others.
Reviewer 3 Report
Comments and Suggestions for AuthorsThis is my first review of the manuscript entitled "Light Energy Use Efficiency in Photosystem II of Tomato is Related to Leaf Age and Light Intensity" by Moustaka et al.
The manuscript under review reports the results of comparison of young and mature tomato leaves in terms of their efficiency during light phase of photosynthesis. The manuscript provides details about various PAM metrics response to low and high levels of actinic light of two groups of leaves, young and mature. Reading the manuscript left a number of questions which are listed below.
First of all, the Materials and Methods unfortunately lack of some details that would facilitate reproducibility of the research. Authors report that tomato plants were obtained from marketplace. What was the age of these plants? Were they seedlings, or flowering plants? What was the age difference between young and mature leaves, their size and specific leaf area?
What time of the day (relative to photoperiod conditions in growth chamber) was chosen for experimental procedures? All that should be added to the section 2.1.
Abstract, L15: it is unclear what 'developmental stage' of the leaf do authors refer to.
L40–41: actually, leaf is not a tissue but an organ of plant. Please correct.
L42: this statement reads like that LHCII complexes are the only pigment-protein complexes that absorb photons to transfer energy to PSII RC, which is not correct: PSII core antennae complex could do that, and even P680 chlorophylls could be excited directly, but at a lower rate.
L45–46: this sentence needs punctuation correction, otherwise it looks incomplete.
L144, L162, L177, L188, L199, L208, figure captions: please specify sample size (n=?)
Figures 2, 3, 4, 5: authors should put the X axis title, currently X-axes on these figures contain only values and units of measurement.
Figure 6: the white asterisk as well as numbers on some images on the figure panel are barely visible. I would suggest to put these outside the leaf silhouettes so that inscriptions do not interfere with image and are readable.
L201: actually, fig. 6 shows representative pseudocolor images where various metrics are mapped using color lookup table.
L280: authors refer here to 'growth rate', but it is not clear which rate do they mean: whether that is leaf growth rate, or the whole plant growth rate / biomass accumulation, or fruit mass as a metric important for nutritional quality. If that was measured, please provide data. If not, then at least the phrase must be more precise.
Finally, conclusion enumerates the findings in a very concise way, which is totally acceptable, but there is no outcome, or resulting suggestion on the ways of the implementation of research findings into real agriculture to facilitate yield or protect young leaves from photoinhibition.
Supplementary table serves a good job as a reminder for PSII quantum yield etc. Please consider enumerating basic parameters that are directly measured such as Fm, Fo, Ft (Fs).
Authors are expected to address these issues and other reviewers' comments to further improve the manuscript.
Comments on the Quality of English LanguageThe language is mostly fine, however requires proofreading, numerous corrections of punctuation, some typos and incorrect use of prepositions and pronouns.
L18: excessive comma after 'leaves'.
L25: please check what is 'open fraction'.
L30: should be 'We conclude'.
L45–46: this sentence needs punctuation correction.
L111: wrong tense of the verb 'affect'.
L122: authors probably wanted to put 'conducted' instead of 'contacted'.
L234: literature reference brackets need a comma.
L239: 'corelated' or 'correlated'?
L274: excessive pronoun 'they', please check.
L276: excessive comma.
Author Response
Comments and Suggestions for Authors
This is my first review of the manuscript entitled "Light Energy Use Efficiency in Photosystem II of Tomato is Related to Leaf Age and Light Intensity" by Moustaka et al.
Dear Reviewer,
We would like to thank you for dedicating the time and the effort to review our work and for the valuable comments and suggestions that we adopted in our revised manuscript
The manuscript under review reports the results of comparison of young and mature tomato leaves in terms of their efficiency during light phase of photosynthesis. The manuscript provides details about various PAM metrics response to low and high levels of actinic light of two groups of leaves, young and mature. Reading the manuscript left a number of questions which are listed below.
Answer: In our revised manuscript we have addressed all your comments.
First of all, the Materials and Methods unfortunately lack of some details that would facilitate reproducibility of the research. Authors report that tomato plants were obtained from marketplace. What was the age of these plants? Were they seedlings, or flowering plants? What was the age difference between young and mature leaves, their size and specific leaf area?
Answer: We included such information on the revised manuscript. The growth stage according to the BBCH scale was included and a supplemental Figure was provided showing the age difference between young and mature leaves (Figure S1.)
What time of the day (relative to photoperiod conditions in growth chamber) was chosen for experimental procedures? All that should be added to the section 2.1.
Answer: Measurements were performed from 10.00 am to 13.00, which is equal to 2h after lights were on at the growth chamber that provided the plants with 420 ± 10 μmol quanta m−2 s−1 for 14 h constantly. However, since all leaves were dark adapted for 30 min before measurements, in order all the reactions centers to be open, the time relative to the photoperiod conditions in the growth chamber it does not matter.
Abstract, L15: it is unclear what 'developmental stage' of the leaf do authors refer to.
Answer: We change it to “leaf age” and since in the beginning of the sentence it is mentioned young or mature leaves, it is now clear.
L40–41: actually, leaf is not a tissue but an organ of plant. Please correct.
Answer: Yes, corrected it to organs.
L42: this statement reads like that LHCII complexes are the only pigment-protein complexes that absorb photons to transfer energy to PSII RC, which is not correct: PSII core antennae complex could do that, and even P680 chlorophylls could be excited directly, but at a lower rate.
Answer: The sentence was rewritten.
L45–46: this sentence needs punctuation correction, otherwise it looks incomplete.
Answer: Corrected.
L144, L162, L177, L188, L199, L208, figure captions: please specify sample size (n=?)
Answer: We added in the figure captions: “Eight to ten plants were measured from each treatment (n = 8–10).”
Figures 2, 3, 4, 5: authors should put the X axis title, currently X-axes on these figures contain only values and units of measurement.
Answer: We put a title to the X axis in all Figures.
Figure 6: the white asterisk as well as numbers on some images on the figure panel are barely visible. I would suggest to put these outside the leaf silhouettes so that inscriptions do not interfere with image and are readable.
Answer: Value numbers and asterisks were put outside the “leaf silhouettes”.
L201: actually, fig. 6 shows representative pseudocolor images where various metrics are mapped using color lookup table.
Answer: We added that Figure 6 is a representative whole leaf pseudocolor coded image.
L280: authors refer here to 'growth rate', but it is not clear which rate do they mean: whether that is leaf growth rate, or the whole plant growth rate / biomass accumulation, or fruit mass as a metric important for nutritional quality. If that was measured, please provide data. If not, then at least the phrase must be more precise.
Answer: We added “leaf” growth rate.
Finally, conclusion enumerates the findings in a very concise way, which is totally acceptable, but there is no outcome, or resulting suggestion on the ways of the implementation of research findings into real agriculture to facilitate yield or protect young leaves from photoinhibition.
Answer: Conclusion section was extended, and a recommendation for agricultural studies based on our results was included.
Supplementary table serves a good job as a reminder for PSII quantum yield etc. Please consider enumerating basic parameters that are directly measured such as Fm, Fo, Ft (Fs).
Answer: We added as you suggested in the Supplementary table the basic parameters that are directly measured (Fm, Fo, Fm’, Fo’, Fs).
Authors are expected to address these issues and other reviewers' comments to further improve the manuscript.
Thank you again for your constructive comments.
Comments on the Quality of English Language
The language is mostly fine, however requires proofreading, numerous corrections of punctuation, some typos and incorrect use of prepositions and pronouns.
L18: excessive comma after 'leaves'.
L25: please check what is 'open fraction'.
L30: should be 'We conclude'.
L45–46: this sentence needs punctuation correction.
L111: wrong tense of the verb 'affect'.
L122: authors probably wanted to put 'conducted' instead of 'contacted'.
L234: literature reference brackets need a comma.
L239: 'corelated' or 'correlated'?
L274: excessive pronoun 'they', please check.
L276: excessive comma.
Answer: Thank you for pointing out all these mistakes. We corrected them in our revised manuscript.
Round 2
Reviewer 3 Report
Comments and Suggestions for AuthorsThis is my second review of the manuscript entitled "Light Energy Use Efficiency in Photosystem II of Tomato is Related to Leaf Age and Light Intensity" by Moustaka et al.
The reviewer is happy to see the detailed response of the authors. Nevertheless, just a few issues left.
First, authors say that "We added as you suggested in the Supplementary table the basic parameters that are directly measured (Fm, Fo, Fm’, Fo’, Fs)." Nevertheless, the Supplementary materials file that they have uploaded, consists of the S1 Table that is exactly the same as the one supplied with the initial version of the manuscript. Authors should upload the correct version of Supplementary.
Second, authors included the description of tomato plants used in the study, and their growth stage. L116–117 of the revised manuscript reads as "with leaf developmental stage 15 according to the BBCH scale", and it would be a good idea to provide there an actual reference to that scale.
Hopefully, these corrections will not require much effort from the authors.
Author Response
This is my second review of the manuscript entitled "Light Energy Use Efficiency in Photosystem II of Tomato is Related to Leaf Age and Light Intensity" by Moustaka et al.
The reviewer is happy to see the detailed response of the authors. Nevertheless, just a few issues left.
First, authors say that "We added as you suggested in the Supplementary table the basic parameters that are directly measured (Fm, Fo, Fm’, Fo’, Fs)." Nevertheless, the Supplementary materials file that they have uploaded, consists of the S1 Table that is exactly the same as the one supplied with the initial version of the manuscript. Authors should upload the correct version of Supplementary.
Answer: We apologize for uploading a wrong version of Table S1. Thank you for checking it.
Second, authors included the description of tomato plants used in the study, and their growth stage. L116–117 of the revised manuscript reads as "with leaf developmental stage 15 according to the BBCH scale", and it would be a good idea to provide there an actual reference to that scale.
Answer: A reference [46] has been included for the BBCH scale.
Hopefully, these corrections will not require much effort from the authors.
Thank you again for your constructive comments.
