Optimizing Nitrogen Application Enhances Sugar Beet (Beta vulgaris L.) Productivity by Modulating Carbon and Nitrogen Metabolism
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsIn this study, the effects of split nitrogen application on sugar beet leaf development, dry matter accumulation, carbon-nitrogen metabolism, and yield were evaluated, with the goal of identifying the most effective fertilization strategy to enhance sugar beet productivity. The work is interesting and provides valuable insights into improving sugar beet production. However, the comments provided should be considered to enhance the manuscript's readability and clarity, which would further strengthen the impact and accessibility of the study.
Abstract
The abstract exceeds the ideal length (approximately 200 words maximum) and would benefit from a more concise presentation. Refining the wording to focus on key objectives, methods, and results will improve clarity and alignment with standard abstract guidelines.
Introduction
L57-60 Reference 12 does not appear to align with the content it is meant to support. It is advisable to reassess its placement and consider citing a more appropriate source that better substantiates the statement.
Lines 73-78 the phrasing is somewhat repetitive and could be more concise.
Lines 67–77 could be removed or integrated after lines 79–97 to improve the logical flow and avoid redundancy. The current structure creates unnecessary repetition and disrupts the clarity of the argument, which would benefit from a more streamlined presentation.
Lines 84-85 the sentence "Numerous studies on crops have demonstrated that nitrogen application significantly alters carbon and nitrogen metabolism" is too vague, as it references "numerous studies" without citing specific sources. The claim lacks proper citation, and the relevant studies should be identified to support this assertion.
The gap on which the study is based is not clearly defined. The rationale for the research and how it addresses existing knowledge gaps needs to be more explicitly stated to provide a clear context for the study’s objectives.
The aim of the study is currently presented in a very summarized manner. Expanding on it with more detail would provide clearer insight into the research objectives and the significance of the work.
Materials and Methods
More information is needed regarding the accessions used in the experimental design, including details about the specific varieties studied. Additionally, the number of repetitions should be clearly stated to assess the reliability and statistical significance of the results.
- Sampling period
The methodology lacks details on whether liquid nitrogen was used during the transport of the sugar beet plants to the laboratory for preservation. Additionally, it would be useful to specify the conditions under which the plants were transported and stored to ensure that the samples remained intact for further analysis.
In Figure 2, the distinction between the root growth and sugar accumulation stages is not clearly visible. It would be helpful to provide a more representative photo or an enhanced visual to better illustrate the differences between these stages.
The formula for Leaf Area Index (LAI) used in the study is not accompanied by a reference to support its application. If no specific study is cited, a more detailed explanation of the formula and its relevance to this experiment is needed to clarify its use and ensure scientific rigor.
Results
The sentence in lines 222-223 is more suitable for the discussion rather than the results section. Moving it to the discussion would improve the logical flow and help differentiate between the presentation of results and their interpretation.
The results presented in Figures 3a and 3b are not sufficiently developed or analyzed. A more detailed explanation of the differences observed is needed to provide a clearer interpretation of the data and its implications.
The ANOVA results are not presented. Given that two factors—year and growth stage—are involved, it is important to mention the significance of each factor as well as their interaction, rather than only presenting the Tukey test results. This would provide a more comprehensive understanding of the factors affecting the outcomes.
Figure 4b is not easily readable and needs to be improved for better clarity. Additionally, as the explanation in the legend is redundant, it would be more concise to retain only one version.
Lines 348-349 / Lines 357-359 are more suitable for the discussion rather than the results section.
In Figure 8a, the labels in the photo are illegible. Please improve the clarity to make them more readable.
Figure 9 is not readable. Please enhance the clarity and resolution to ensure the matrix is legible and the data can be interpreted effectively. The correlation matrix in Figure 9 would benefit from a more thorough exploration. It is recommended to describe the correlation for each year separately and then compare how these correlations change across the two years. This approach would provide a clearer understanding of the temporal variations and trends in the data.
Discussion
The mention of Figure 9 in line 404 seems out of place, as it does not appear to be relevant in that context. It is possible that you meant to refer to Figure 10, which is not mentioned elsewhere in the text. Please clarify and ensure that the correct figure is referenced.
The claim that this is the "first research" to investigate the effects of split nitrogen application on sugar beet growth, ANUE, and yield from the perspective of carbon and nitrogen metabolism seems questionable. Several studies, such as [Li et al.; 2024], have already explored similar topics. Please review the literature to accurately position your study and clarify its novelty in relation to existing work.
Li, Z., Jian, C., Guo, X., Tian, L., Han, K., Li, Y., ... & Su, W. (2024). Effects of different ratios of nitrogen base fertilizer to topdressing on soil nitrogen form and enzyme activity in sugar beet under shallow drip irrigation. PeerJ, 12, e18219.
The discussion section needs further improvement. Instead of merely citing other works as a bibliography, it is essential to compare those studies' findings with your own results. A more detailed analysis of how your findings align with or differ from existing research would strengthen the discussion and provide a clearer interpretation of your data.
It is important to provide a more thorough and detailed discussion of the study's limitations, including potential sources of bias, methodological constraints, or factors that may have influenced the results. This would help readers better understand the scope and validity of your findings.
Conclusions
The conclusion could be strengthened by providing a more comprehensive summary of the key findings and their implications.
Author Response
Please see the attachment
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsDear Authors,
congratulations on your work, which contributes valuable new information to the topic. However, a few aspects need clarification:
1) In line 210, please explain why the measured value must be multiplied by 0.83 to determine the sugar content.
2) In line 211, clarify whether the formula considers the elimination of non-marketable and/or waste root quantities first.
3) In line 274, the presentation of Figure 4 is somewhat difficult to comprehend due to the large amount of data. Please consider a clearer and more readable format.
Best regards
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for AuthorsThe manuscript entitled “Optimizing nitrogen application enhances sugar beet (Beta vulgaris L.) productivity by modulating carbon and nitrogen metabolism” investigated the effect of different nitrogen fertilizer application approaches on chlorophyll content, leaf area index (LAI), dry matter accumulation, carbon and nitrogen metabolism, root yield, sugar content, and sugar yield. Overall, the paper is well written, but there are some points, especially in the results and discussion. Please see more comments below:
The abstract section is too long and should be modified. Furthermore, the conclusion of the abstract is not impressive. The authors should clearly state the most significant results and their final conclusions.
I strongly suggest that the authors add previous research about the application of different types of amendments and fertilizers on root yield and sugar content in the introduction section. Here is a recently published work and you can use it here: https://doi.org/10.1016/j.jclepro.2024.143772
The research hypothesis is missing; add it at the end of the introduction section.
Line 175: add reference(S) for each equation in the paper.
In the results section, the authors should compare treatments with the percentage of increase or decrease. This method of report is boring for readers.
Add the definitions for abbreviations in Figure captions; in many cases, readers initially skip to the figures!
Discussion not enough at all, there is not a good connection between the results of the current research and previous ones!!!! I strongly recommend adding more references in this section and improving the discussion with the comparison with the previous one.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors have addressed all the comments and made noticeable improvements to the overall quality and clarity of the manuscript.
Thank you for the clarification regarding the data analysis approach. To enhance transparency and reproducibility, it would be helpful to explicitly state in the Statistical Analysis section that the two years were treated as independent repetitions and that separate ANOVAs were performed for each growth stage.
Author Response
The authors have addressed all the comments and made noticeable improvements to the overall quality and clarity of the manuscript.
Thank you for the clarification regarding the data analysis approach. To enhance transparency and reproducibility, it would be helpful to explicitly state in the Statistical Analysis section that the two years were treated as independent repetitions and that separate ANOVAs were performed for each growth stage.
Response:
We sincerely thank you for your thoughtful re-evaluation and kind words regarding the improvements in our revised manuscript. Your recognition means a great deal to us. We are truly thankful for the precision and professionalism you demonstrated as a reviewer. Your professional and constructive suggestions throughout the review process have been instrumental in enhancing the overall clarity, structure, and scientific rigor of our work. It is truly a privilege to receive feedback from such a meticulous and responsible reviewer. Once again, we deeply appreciate your time, expertise, and generous contribution to the improvement of our manuscript.Reviewer 3 Report
Comments and Suggestions for AuthorsNo, more comments. The revised version is acceptable.
Author Response
No, more comments. The revised version is acceptable.
Response: We sincerely thank you for your time and efforts in reviewing our manuscript. Your recognition means a great deal to us, and we are truly grateful for your support. We deeply appreciate your constructive insights and professional attitude throughout the review process. Your positive evaluation of the revised manuscript greatly motivates us and affirms the value and significance of our research. Thank you again for your kind contribution to the improvement of our manuscript.
