Drought Tolerance Mechanisms in Grain and Vegetable Amaranthus Species: Physiological, Biochemical and Molecular Insights

Round 1

Reviewer 1 Report (Previous Reviewer 1)

Comments and Suggestions for Authors

This is a  well-structured and comprehensive review that addresses a critical topic: the potential of underutilized Amaranthus species as climate-resilient crops. The manuscript is logically organized, and the scope is ambitious, covering morphological, physiological, biochemical, and molecular traits. The work is suitable for publication after addressing the points below:

1) First of all, I think this article lacks a mechanism diagram. Although the author provided some experimental pictures, they are of little significance.

2）The abstract is strong but could be slightly more specific. The phrase "research on the molecular response of vegetable amaranth is not fully elucidated" could be sharpened to "research on the molecular response of vegetable amaranth remains limited."

The final sentence is a great call to action. Consider making it even stronger: "...future research must focus on integrated biochemical, molecular, and multi-omics approaches to screen and identify resilient Amaranthus genotypes for sustainable agriculture."

3）Introduction: You could further emphasize its "C4 pathway" and "high nutrient content" as direct links to its drought resilience and nutritional security value, reinforcing the core thesis.

4) Figure 1: This is a superb conceptual figure. Ensure all abbreviations in the key are defined in the figure caption. 

5) 3.1.3 & 3.2.4: The molecular section is detailed and excellent. The vegetable molecular section correctly identifies the major knowledge gap. You could slightly strengthen this section by more explicitly stating that this gap represents the single biggest opportunity for future research in vegetable amaranth improvement.

6) Conclusion: Consider adding a sentence to explicitly state that bridging the molecular knowledge gap for vegetable amaranths, perhaps using the advanced genomic resources now available for grain species, should be a top priority. This would provide a powerful and forward-looking ending.

7) Please ensure all in-text citations are correctly formatted and match the list.

Author Response

Author's Reply to the Review Report (Reviewer 1)

Comment 1: First of all, I think this article lacks a mechanism diagram. Although the author provided some experimental pictures, they are of little significance.

Reply: Thank you for your insight, table 1 was generated with the aim to show the knowledge gap and also the mechanism of drought tolerance in Amaranths. However, based on your suggestion, we have also included a mechanism diagram (Figure 4), which summarizes the information provided in Table 1.

 

Comment 2: The abstract is strong but could be slightly more specific. The phrase "research on the molecular response of vegetable amaranth is not fully elucidated" could be sharpened to "research on the molecular response of vegetable amaranth remains limited."

Reply: Thank you for your insightful input, we have implemented the comment in the.

 

Comment 3: The final sentence is a great call to action. Consider making it even stronger: "...future research must focus on integrated biochemical, molecular, and multi-omics approaches to screen and identify resilient Amaranthus genotypes for sustainable agriculture."

Reply: We have implemented this suggestion under the concluding line of the abstract.

 

Comment 3: Introduction: You could further emphasize its "C4 pathway “and "high nutrient content" as direct links to its drought resilience and nutritional security value, reinforcing the core thesis.

Reply: Thank you, we have elaborated on that aspect, see revised resubmitted manuscript.

 

Comment 4: Figure 1: This is a superb conceptual figure. Ensure all abbreviations in the key are defined in the figure caption.

 

Reply: Thank you very much for the complement. All abbreviations have been defined and are listed alphabetically.

Comment 5: 3.1.3 & 3.2.4: The molecular section is detailed and excellent. The vegetable molecular section correctly identifies the major knowledge gap. You could slightly strengthen this section by more explicitly stating that this gap represents the single biggest opportunity for future research in vegetable amaranth improvement.

Reply: Thank you for the suggestion, we have added this insightful input to improve our manuscript under section 3.2.4.

 

Comment 6: Conclusion: Consider adding a sentence to explicitly state that bridging the molecular knowledge gap for vegetable amaranths, perhaps using the advanced genomic resources now available for grain species, should be a top priority. This would provide powerful and forward-looking ending.

Reply: Thank for your suggestion, Information has been added in the conclusion section.

 

Comment 7: Please ensure all in-text citations are correctly formatted and match the list.

Reply:  Thank you, all citations have been formatted correctly and are matching the reference list.

Reviewer 2 Report (Previous Reviewer 2)

Comments and Suggestions for Authors

Dear authors,

The paper is very interesting and provides extensive data on Amaranth species and their drought tolerance. Also, compared to the previous version, the paper is highly improved. However, there are still some minor English language issues that needs to be addressed.

1. Please, check the fluency of the text once again and make necessary corrections.
2. Please be careful when using abbreviations for the first time in the text, as there are cases when they are not explained.
3. Please check the usage of word "Furthermore" as in some places it appears twice in a row.
4. Revise the Conclusions section , especially the last sentence, which seems illogical.
5. In table 1., you do not have molecular traits described for some Amaranthus species. Please check once again available literature on the molecular traits/mechanisms of A. tricolor for drought tolerance.

Comments on the Quality of English Language

There are some minor English language issues. Please, check the fluency of the text once again and make necessary corrections.

Author Response

Author's Reply to Reviewer 2 report

 

1. Please, check the fluency of the text once again and make necessary corrections.

Reply: Thank you, we submitted the manuscript to an English editor (details of the editor, will be submitted to the editor).

2. Please be careful when using abbreviations for the first time in the text, as there are cases when they are not explained.

Reply: Thank you for your comment, we checked that all the abbreviations are written in full when used for the first time.

 

3. Please check the usage of word "Furthermore" as in some places it appears twice in a row.

Reply: Thank you for your comment, this has been noted and addressed.

 

4. Revise the Conclusions section, especially the last sentence, which seems illogical.

Reply: Thank you for your input, the conclusion has been rephrased.

 

5. In table 1., you do not have molecular traits described for some Amaranthus Please check once again available literature on the molecular traits/mechanisms of A. tricolor for drought tolerance.

Reply: Thank you for your suggestions, however, to the best of our knowledge there are no reported molecular traits in A. tricolor under drought stress, except for one article, which described the protein analysis on an SDS gel under water stress and CO₂, focusing on the expression of RuBISCO, which actually according to the authors the protein profile and expression was not modified under their treatment (Chatti and Manju, 2017). We have added this reference but as relevance to biochemical response and not molecular.

Reviewer 3 Report (Previous Reviewer 3)

Comments and Suggestions for Authors

The revisions are satisfactory and the manuscript can be accepted for publication in its present form.

Author Response

Author's Reply to the Review Report (Reviewer 3)

The revisions are satisfactory and the manuscript can be accepted for publication in its present form.

Reply: Thank you for your c comments and approval of our manuscript.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This is a review article on the response of grain and vegetable species of Amaranthus to drought stress, covering morphological, physiological, biochemical, and molecular characteristics. The review explores in detail the adaptation mechanisms of different Amaranthus species under drought conditions, including antioxidant accumulation, osmoregulation, antioxidant systems, and gene expression associated with drought response. The review emphasizes the potential of amaranths as drought-tolerant crops, especially in arid and semi-arid regions, as well as their advantages in terms of nutrition and antioxidant content.

Overall, the review is clearly structured with detailed explanations and references in each section, which helps readers to understand how amaranths are adapted to arid environments.

Although the review provides a comprehensive overview of drought response mechanisms in Amaranthus, the article may need further improvement and revision in some areas:

1) 1. The section on Origin and classification of Amaranthus is unnecessary and I think it could be merged with Introduction and needs to be streamlined in terms of content.

2) Why the authors just selected 6 Grain Amaranthus species included in this review?More explanation needs to be given.

3) Why did the authors have to introduce each of the 6 species one by one instead of merging them together in the review?

4) The references cited in the article are not up-to-date. Given that drought stress response is an active area of research, authors are advised to update the cited literature to reflect the latest findings.

5) The article discusses drought response mechanisms in Amaranthus, but whether these mechanisms are generally applicable to other Amaranthus species or are effective under all environmental conditions needs to be further explored.

6) The article makes suggestions for future research, but could be more specific about which areas need further exploration, such as the role of specific genes or metabolic pathways in drought response.

Comments on the Quality of English Language

Minor editing of English language required.

Reviewer 2 Report

Comments and Suggestions for Authors

Dear Authors, the paper is interesting although some parts are hard to read and understand - please revise the parts according to suggestions given as comments directly in the PDF version. Other issues need attention (comments in PDF version).

Secondly, as there is insufficient data on the drought tolerance of the Amaranth species described, in order to achieve desirable impact and contribution to the field, I suggest improving the paper by adding sections about their yield, growing possibilities, and nutritional value. 

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The English of the text needs to be improved. I have highlighted and commented on some issues. However, I suggest revision by a native English speaker or expert.

Reviewer 3 Report

Comments and Suggestions for Authors

The manuscript “Response of grain and vegetable Amaranthus species to drought stress: Physiological, Biochemical and Molecular traits” reviews the drought response mechanisms of various Amaranthus species, emphasizing their physiological, biochemical and molecular traits. The review aims to highlight the potential of these underutilized crops in enhancing food security, particularly in arid and semi-arid regions. I believe, the manuscript needs some important revisions and here are my suggestions;

1.      I suggest title could be modified as “Comprehensive evaluation of drought tolerance mechanisms in grain and vegetable Amaranthus species: Insights through physiological, biochemical and molecular responses”.

2.      The keywords can be expanded. The current keywords are ok but including specific terms like "osmotic adjustment" or "antioxidant response" etc. would be better.

3.      The abstract is too long and overly dense with the information. It could be improved by simplifying the language and breaking down complex ideas into more readable and logical sentences.

4.      There are loads of grammatical errors such as line 86 "relative eater content" should be "relative water content", line 110 should be “..it served as a staple food..”, line 114 should be “..colors and shapes of the flowers and panicles are considered..”, line 119 should be “..each Amaranthus species is further grouped..”, line 128 should be “Amaranthus is a special type of crop..”,  and so on.

5.      While the introduction provides a good overview, it would be beneficial to include more recent references to ground the discussion in the latest research.

6.      The transitions between sections are abrupt and could be smoother. For example, the transition from the introduction to the discussion on Amaranthus species' drought response (lines 127-135) is particularly abrupt.

7.      The last lines of introduction section should highlight the aims and objectives of the study with special focus on how this study would help the readers.

8.      There are instances where information is repeated, such as the discussion of the physiological traits of Amaranthus species in multiple sections. Avoid repetition.

9.      There are inconsistencies in the citation style throughout the paper, for example line 204, 205, 233, 240 and many more. Ensuring that all references follow the same format is important.

10.  Conclusion is too long too. Please shorten it to 300 to 350 words.

11.  The conclusion section repeats points made earlier in the paper without offering new insights. It could be more concise and focused on future research directions.

12.  The article has inconsistent use of punctuation, particularly in the placement of commas and semicolons. A thorough proofreading is necessary.

13.  Overall, the article would benefit greatly from a thorough proofreading to correct grammatical errors, improve sentence structure, and ensure consistency in formatting and style.

Comments on the Quality of English Language

Minor editing of English language is required.