Exogenous Application of Methyl Jasmonate at the Booting Stage Improves Rice’s Heat Tolerance by Enhancing Antioxidant and Photosynthetic Activities

Round 1

Reviewer 1 Report

Methyl jasmonate (MeJA) has been identified to play multi-functional and stress-alleviatory roles in plants under various abiotic stress conditions. The present manuscript entitled “Exogenous Methyl Jasmonate on the Physiological Characteristics, Yield and Quality of Rice under High Temperature at Booting Stage” provides some new information about the effect of MeJA in alleviating high temperature during the rice booting stage. The experiments have been properly conducted and the results are interesting. However, some experimental data are conflicting. Accordingly, there are minor corrections that authors should address:

1.     Lines 42, “and further result in reduced yieldh [1,2].”, misspell “yield”.

2.     Lines 179 to 187, these two paragraphs can be merged together.

3.     Fig.1, lack of statistical analysis.

4.     Fig.2, missing ordinate unit.

5.     Fig.4 “%” should be in the parentheses.

6.     For the data presented in all the tables, I suggest authors to add the standard deviation.

7.     Discussion section, lines 470 to 473, “Results showed the spraying of MeJA had no significant effects on grain numbers or grain weight but seemed to have an insignificant improvement in alleviating the yield loss by maintaining seed-setting rate in both varieties under adverse conditions.” Form the data in table 2, significant improvement in seed-setting rate in Wuyunjing 24 rice but not in Ningjing3.

8.     Lines 474 to 476, “Results showed the heat stress could greatly reduce the rice pollen activity and exogenous MeJA alleviated such effects to a certain extent (undisclosed data).” I think the undisclosed data is very useful for the verification of the decreased seed-setting rate under high temperatures.

9.     In the conclusion section, lines 514 to 516, “Exogenous MeJA increased the number of grains per panicle of both varieties and the seed-setting rate of Wuyunjing 24 under high temperature at the booting stage, which alleviated the yield loss induced by high temperature stress.” How could authors make this conclusion? Form the data in table 2, the exogenous MeJA have no significant influence on the number of grains per panicle of the two varieties under high temperature conditions.

10.  References: Please very carefully format the references according to the journal guidelines.

Author Response

We sincerely thank you for your valuable suggestions for reviewing our manuscripts. In the revised manuscript, we have carefully considered your suggestions and made the appropriate revisions. In response to the specific comments you mentioned, we have also responded accordingly.

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The ms agronomy-1767186 with the title of Exogenous Methyl Jasmonate on the Physiological Characteristics, Yield and Quality of Rice under High Temperature at Booting Stage investigate an important issue, but the ms has to be significantly improved before it can go for further step. In this study, the main cultivated japonica rice varieties Wuyunjing 24 and Ningjing 3 were treated with high temperate (37.5°C/27.0°C) and exogenous MeJA (1mmol/L) at booting stage.

Below are my comments:

Title should be improved to be: Exogenous application of xxx

I am wondering why authors chose these specific treatments for temperature (37.5°C/27.0°C) and MeJA (1mmol/L) ? In scientific research the researchers are recommended NOT to use one treatment from each factor. Also, why these concentration of MeJA? Why 1 mM? why not 1, 2, 3?

L23-25 and etc. All abbreviations should be defined in first mention, please revise this issue in the whole ms!

L39 Key words it should be ONE word i.e. Keywords

L37 and other lines: All Latin names for plant species should be ITALIC! Please correct this issue in the whole ms.

L40 cite these relevant ref:

https://doi.org/10.3390/su12062159

https://doi.org/10.1016/j.chemosphere.2017.11.053

L44-45 make st and th superscripts, check similar issues and revise in whole ms.

L46-50 please cite the suitable references.

L51-55 please cite this recent and suitable reference: Rasheed et al. Agronomic and genetic approaches for enhancing tolerance to heat stress in rice: A review. Not. Bot. Horti Agrobot. Cluj-Napoca 2021, 49, 12501.

Are they rice varieties or rice cultivars? Please check

In material and methods, please cite all described methods because these methods are not your own.

L 172 (α=0.05) correct it to (P≤0.05)

L174 Please add the full information for SPSS such as company name, cite and country, remember that these information was changed because there is new owner for SPSS.

In the statistical analysis, and the results in Tables or Figures should be revised. The authors should compare the two cultivars of rice with each other grown under different treatments of temperature and MeJA. So, you can accurately state which cultivar was better than the other one. From what I see now, the authors made this separately which means that the statistical analysis was not done correctly. For example, in Table 1, the authors should compare the 8 means under Pn with each other instead of comparing only 4 means under each cultivar separately. Consequently, the authors should revise the text in results and discussion according to this suggestion.

I suggest the authors to add standard error SE or standard error of means SEM for values in Tables, letters are not enough sometimes. In Figures, they added SD or SE

In figures, authors should define what bare are mean?

The discussion section is good, but it was superficial written and I wish the author to focus of the mechanisms of MeJA in mitigating heat stress.

I am sure that the authors will do great job to revise their ms and make it stronger.

Best regards, reviewer

 

 

 

 

 

 

Author Response

We sincerely appreciate the time and effort that you dedicated to providing feedback on our manuscript and are grateful for the insightful comments on and valuable improvements to our paper. We have adopted your suggestions and made substantial revision to the relevant sections of the manuscript. 

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

This study estimated the “Exogenous Methyl Jasmonate on the Physiological Characteristics, Yield and Quality of Rice under High Temperature at Booting Stage”.

To be honest I cannot accept this manuscript in this form.

Abstract:

(1) The abstract is very poorly constructed. This part needs to be completely re-written, especially the presentation of the results.

(2) Language used in this section is very bad.

Introduction: Introduction is poorly written.

(3) Authors did not refer to any studies dealing with the harmful effects of heat stress on rice photosynthetic activity and antioxidant capacity. They should incorporate the previous studies, especially the latest ones.

(4) Please also illustrate the benefit impacts of using exogenous methyl Jasmonate on the measured parameters.

(5) The introduction is written chaotically. There is no hypothesis or purpose of the study. The hypothesis and objective must be in line with the defined problem.

Material and methods:

(6) The experiment has apparently done only once, and I do not see repetitions. In general, for plant experiments, it is recommended that the repeatability of the experiment be for 2 years.

(7) Moreover, the study should contain full soil chemical analysis.

(8) The authors should explain why they used this concentration of methyl Jasmonate (1 mmol/L  MeJA).

(9) I wonder that the authors

In Material and methods section in Line 106: they said that:

The net photosynthetic rate, stomatal conductance, and transpiration rate were measured.

However in results section in Lines 196-198: they talk about net photosynthetic rate, stomatal conductance, transpiration rate, and intercellular CO₂ concentration.

(10) In Table 1: I did not understand what is Cond?

(11) I wonder that the authors

In Material and methods section in Lines 111- 113: they said that:

and then the maximum quantum yield of PSII was then measured (Fv/Fm). Variable fluorescence and maximum fluorescence ratio (Fv′/Fm), photochemical quenching coefficient (qP), actual photochemical efficiency (ΦPSII), non-photochemical quenching (the NPQ) and electron transport rate (ETR) were measured.

However in results section in Fig. 2: they gave data for photosystem II (FPSII), photosynthetic electron transport rate (ETR) and photochemical quenching coefficient (qP).

(12) In Fig. 2: I did not understand what is phipsII?

(13) Shall I ask the authors did they do this work or not.

Because for the third time In Material and methods section in Lines 121- 130: Authors measured only SOD and POD.

However in results section in Fig. 3: they gave data for SOD, POD, CAT, and APX.

Shall authors explain it for me  !!!!!!!  ????????

(14) in Line 170: what is NSC content?

(15) How much plants were taken for different analysis should be mentioned clearly.

Results: are poorly written and very unclear.

 (16) At the end of this section, the effect of heat stress is differ between the  two cultivars should be underlined. Moreover, it should be discussed in the discussion section. I wonder that the authors have not shown/discussed any statistical analysis to compare the two rice varieties. The incorporation of statistical analysis showing the genotypic comparison will further improve the manuscript and strengthen the conclusions.

Discussion: The discussion part is not good.

(17) Why and how heat stress increases or decreases a parameter and why and how methyl Jasmonate increases or decreases a parameter……what are the possible mechanisms, should be mentioned in the discussion part.

(18) At the end of discussion section, all evaluated parameters should be well integrated and discussed.

Conclusion:

(19) The conclusion section must be rewritten.

Elaborate the conclusion.

Linguistic quality:

(20) The language quality is so poor and this paper must be edited by professional English editor.

Author Response

We sincerely thank you for your valuable suggestions for reviewing our manuscripts. In the revised manuscript, we have carefully considered your suggestions and made the appropriate revisions. In response to the specific comments you mentioned, we have also responded accordingly.

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Dear Authors

Thank you, the ms has been significantly improved based on my suggestions. Now, the ms can be accepted for publication in Agronomy.

 

Best regards, Reviewer

Author Response

We sincerely appreciate your time and effort to provide feedback on our manuscript, and thank you for your recognition of our work.

Reviewer 3 Report

I have several major concerns with the manuscript which prevent me from recommending it for publication in its current situation.

The main concern is:

(1) All abbreviations should be defined in first mention, please revise this issue in the whole manuscript!

(2) The English still requires to be improved.

Title:

(3) Should be improved to be: 

Exogenous Application of Methyl Jasmonate at Booting Stage improves rice heat tolerance by enhancing antioxidant and photosynthetic activities

Abstract:

(4) Lines 14-17. This paragraph should be re-write.

 Introduction:

(5) Line 59. This sentence should be re-write.

(6) Lines 103-108 please correct this paragraph. All the information you give in this paragraph is wrong.

Ascorbate peroxidase (APX) is not chlorophyll fluorescence parameter, it is antioxidant enzyme. Moreover, stomatal conductance (Gs), intercellular carbon dioxide concentration (Ci), and net photosynthetic rate (Pn) are not chlorophyll fluorescence parameters, they are gas exchange attributes.

(7) Lines 109-112 please put references.

Material and methods:

(8) Line 189. You said At least three replicates for each treatment.

Please how many replicates you used exactly?.

(9) Lines 200-203. Please cite all described methods because these methods are not your own.

(10) Lines 223-230. Determination of cytokinin (CTK) and abscisic acid (ABA). Please cite the method because this method is not your own.

Comments for author File: Comments.docx

Author Response

We sincerely appreciate the time and effort that you dedicated to providing feedback on our manuscript and are grateful for the insightful comments on and valuable improvements to our paper. We have adopted your suggestions and made substantial revision to the relevant sections of the manuscript. Please see the attachment.

Author Response File: Author Response.docx