Near-Freezing Temperature Storage Improves Peach Fruit Chilling Tolerance by Regulating the Antioxidant and Proline Metabolism
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsThe paper offers a comprehensive analysis of the impact of near-freezing temperature (NFT) storage on chilling injury (CI), proline metabolism, and antioxidant capability in peach fruit, contrasting with conventional storage temperatures (5°C and 0°C).
This MS requires overall improvement, with a particular focus on enhancing the introduction, which currently lacks depth. The current figures are insufficiently presented for scientific rigor; a comprehensive overhaul is necessary to ensure their adequacy for scholarly work. Clarity must be extended to both the written and visual components of the MS, necessitating revisions to all figures. The authors are urged to address comments embedded in the text, as they provide valuable insights for the general improvement of the work. Additionally, adhering strictly to the guidelines outlined by the horticulturae journal is crucial for maintaining the scholarly integrity of the references. By implementing these refinements, the manuscript will undergo a significant enhancement in terms of content, presentation, and overall quality:
The abstract could be refined for clarity and precision:
- Begin by succinctly addressing the prevalent issue of chilling injury in peach fruit storage.
- Clearly highlight key findings, such as the complete inhibition of chilling injury observed in peach fruit under NFT storage conditions.
- Explicitly state the practical implications of the study for peach fruit storage practices.
The introduction effectively outlines the background and context of the study on peach fruit storage, chilling injury (CI), and the potential benefits of near-freezing temperature (NFT) storage. Here are suggestions for enhancing the introduction:
- Provide more depth and context regarding the significance of chilling injury in peach fruit storage, possibly including statistics or industry insights.
- Clearly articulate the rationale for investigating NFT storage as a potential solution to mitigate chilling injury and improve fruit quality.
- Strengthen the transition between the background information and the specific objectives of the study, ensuring clarity and cohesion.
The Results, Discussion and Conclusion sections should be reworded for improved clarity and coherence, taking into account the provided comments in the attached file. Ensure that the key findings are summarized succinctly and aligned with the study's objectives. Additionally, address any limitations or implications of the findings for future research or practical applications in peach fruit storage. Strive for a cohesive narrative flow that effectively synthesizes the study's findings and their broader implications.
Comments for author File: 
Comments.pdf
Moderate editing of English language required
Author Response
Dear Editor and Reviewer,
Thank you very much for giving us an opportunity to revise our manuscript entitled “Near-freezing temperature storage improves peach fruit chilling tolerance by regulating the antioxidant and proline metabolism” (horticulturae 2918394).
We have revised our manuscript carefully according to the comments, and would like to re-submit it for your consideration. The amendments are highlighted in yellow color in the revised manuscript. Our responses to the referees are listed by point to point in the following sections.
We would like to express our great appreciation to you and reviewer for the comments and hope that revised manuscript is acceptable.
Look forward to hearing from you.
Yours sincerely,
Dr. Handong Zhao
Reply to Referee
The comments and suggestions from you are very valuable. Our revised portions according to the reviewer's comments are listed as following.
To Referee 1
Comment 1: This title is too long. I suggest changing it.
Response: Thank you for your advice. I have deleted the ‘defense system’, and marked it in the manuscript title.
Comment 2: Move the keywords below the abstract.
Response: Thank you for your advice. I have moved the keywords below the abstract and marked in keywords part.
Comment 3: Start the abstract with a concise information addressing the common occurrence of chilling injury in peach fruit during storage.
Response: Thank you for your advice. I have reworded the first sentence in abstract section. “Chilling injury (CI) in peach fruit (Prunus persica cv. Yuhualu) generally caused by long-time low temperature (5 oC or 0 oC) storage.” Revised sentence is marked in the abstract.
Comment 4: peach fruits (Prunus persica cv. Yuhualu)
Response: Thank you for your advice. I have reworded the first sentence in abstract section. “Chilling injury (CI) in peach fruit (Prunus persica cv. Yuhualu) generally caused by long-time low temperature (5 oC or 0 oC) storage.” Revised vocabularies were marked in the abstract.
Comment 5: Indiquer clairement l'objectif principal de l'étude et les températures spécifiques étudiées.
Response: Thank you for your advice. I have added some explain after the “near-freezing temperature” as “(the NFT of this research is -1 oC), which is defined within 0.5 oC higher than the biological freezing point of biological tissue”. Above revision has been marked in the revised manuscript.
Comment 6: Clearly state the implications of the study for practical applications in peach fruit storage. Consider briefly mentioning any limitations or potential areas for future research.
Response: Thank you for your advice. I have revised the last sentence in abstract section as “In conclusion, above results suggested that NFT storage could improve the chilling tolerance of peach fruit through regulate the antioxidant defense and proline metabolism, which might be a potential novel method to store fruit and vegetable for a long storage time.” Above revision has been marked in the revised abstract.
Comment 7: Prunus persica
Response: Thank you for your advice. I have revised as “Peach fruit (Prunus persica cv. Yuhualu).....” in the first line of introduction part of revised manuscript. Above revision has been marked in the revised introduction.
Comment 8: Replace this phrase by “However, postharvest challenges arise due to the climacteric nature of peaches, leading to softening and decay when stored at room temperature. Although low-temperature refrigeration, ranging from 0 °C to 8 °C, is a widely employed strategy to extend peach storage, it often triggers chilling injury (CI).” in line 2-5 of the introduction part.
Response: Thank you for your advice. I have revised my sentence as “However, postharvest challenges arise due to the climacteric nature of peaches, leading to softening and decay when stored at room temperature. Although low-temperature refrigeration, ranging from 0 oC to 8 oC, is a widely employed strategy to extend peach storage, it often triggers chilling injury (CI).” Above revision has been marked in line 2-4 of revised introduction.
Comment 9: The last two sentences in introduction in not correct, please reword this part.
Response: Thank you for your advice. I have revised my sentences as “The CI generally resulted in flesh browning, fibrillation, and aroma loss. Underlying these manifestations are disruptions in plant cell metabolism, including membrane damage, reactive oxygen disorder, and alterations in cell wall materials.”Above revision has been marked in the last of revised introduction.
Comment 10: Why tobacco ??? Explain briefly the critical role of membrane damage and oxidative stress in CI and how the antioxidant defence system and proline metabolism play a role in the cold tolerance of peaches.
Response: Thank you for your advice. I have revised my sentences as “Reactive oxygen species are essential redox signaling factors that involve in the developmental and physiological processes, and induces the expression of defense genes and adaptive response. Nitric oxide treatment could extenuate mitochondrial swelling, maintain mitochondrial membrane potential and membrane fluidity, and delay the decrease in activities of the cytochrome pathway and cyanide-insensitive pathway of the mitochondrial respiratory chain in peach fruit [6]”, and replaced the reference 6. Above revision has been marked in paragraph 2 and references.
Comment 11: Suggest to use this objective of this research in the last paragraph of introduction.
Response: Thank you for your advice. I have revised my sentences as “This research delves into the repercussions of NFT storage on CI, quality, antioxidant properties, and the metabolism of reactive oxygen species and proline in peach fruit. The investigation seeks to unravel potential correlations between antioxidant and proline metabolism and chilling tolerance during NFT storage, presenting valuable insights for the preservation of fresh vegetables and fruits.” Above revision has been marked in the last paragraph of introduction.
Comment 12: Reword the second paragraph of 2.1
Response: Thank you for your advice. I have revised my sentences as “Following established protocols outlined in our previous research [14], the fruits underwent a pre-cooling process at 5 °C ± 0.1 °C for 12 hours. Subsequently, they were randomly divided into three groups: 5 °C (± 0.1 °C), 0 °C (± 0.1 °C), and Near-Freezing Temperature (NFT, -1 °C ± 0.1 °C). The storage duration was 28 days, and the storage conditions included a relative humidity of 90%. Each treatment was replicated three times, with each replicate consisting of 100 peach fruits. Sampling was conducted at 0, 7, 14, 21, and 28 days, and fifteen fruits were sampled from each batch. Tissue slices, approximately 1 cm thick, were rapidly frozen in liquid nitrogen and stored at -80 °C for subsequent analysis.” Above revision has been marked in the second paragraph of 2.1.
Comment 13: In 2.3, I didn't understand how you determined the percentage of browning, what criteria you used to do it, are there any studies that have used the same method?
Response: Thank you for your advice. I have revised the expression to explain the determine method. “The CI degree was investigated by competing the internal browning area of peach transferred to room temperature for three days after storage [16].” Above revision has been marked in the second paragraph of 2.3.
Comment 14: Reword the first paragraph of 2.5
Response: Thank you for your advice. I have revised this paragraph as “The proline content was measured by adding sulfosalicylic acid to ground flesh in an ice bath, followed by boiling and centrifugation [20]. The absorbance of the supernatant was tested at 520 nm, with proline content expressed in mg kg-1.” Above revision has been marked in the first paragraph of 2.5.
Comment 15: Figure 1 caption, SD or SE?
Response: This is the SE (standard error).
Comment 16: Remove negative orientation for SE. Remove negative orientation for SE, please do something for all figures.
Response: Thank you for your advice. The small letters, such as a, b and c, represent within the same days significantly different (P < 0.05) at different temperatures. We have add illustration as “Vertical bars represent the standard error of the means (P < 0.05). Duncan’s test letters represent the difference among the different temperatures within the same days.” Above revisions have added in captions of figure 1 to 5 and marked in revised manuscript.
Comment 17: Move the Figure 6 to result section.
Response: Thank you for your advice. I have moved the figure 6 to result section, which has been marked in revised manuscript.
Comment 18: Conclusion is bad formulated, try to reformulate it.
Response: Thank you for your advice. I have revised this section as “In conclusion, the study highlights intriguing findings regarding the efficacy of NFT storage in mitigating chilling injury in peaches, especially when compared to storage at higher temperatures. Notably, NFT storage exhibited a consistent preservation of elevated levels of antioxidant enzyme activities, ascorbic acid, phenolics, and DPPH scavenging capacity. It effectively mitigated the accumulation of malondialdehyde and inhibited the activity of proline dehydrogenase (PRODH). Additionally, NFT storage facilitated increased proline production and bolstered the overall antioxidant defense system.”, which has been marked in conclusion of revised manuscript.
Comment 19: Chick the underlined references.
Response: Thank you for your advice. These are our mistakes. I have revised these underlined references, and marked them in the reference part of revised manuscript.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Comments and Suggestions for AuthorsOverall, the paper presents a well-structured and well-written study investigating the effects of near-freezing temperature (NFT) storage on chilling injury (CI), proline metabolism, and antioxidant capability in peach fruit. The methods are appropriately described, and the results are well presented and discussed. However, I have two suggestions for improvement:
-
1) Parameters like texture and colour should be evaluated: It would enhance the study's comprehensiveness to include evaluations of texture and colour changes in the peach fruit samples. Texture analysis could provide insights into changes in firmness or softening during storage, which are important quality attributes for consumers. Similarly, colour analysis could provide information on changes in appearance, which is another crucial aspect of fruit quality. Correlating these evaluations with the observed effects of NFT storage on CI, antioxidant capacity, and proline metabolism would strengthen the conclusions and provide a more comprehensive understanding of the impact of NFT storage on peach fruit quality.
-
2) Please, improve the conclusion section: The paper's conclusion could be strengthened by providing a more concise summary of the key findings and their implications. Additionally, it would be beneficial to discuss the practical implications of the research findings for the fruit industry. For example, the potential application of NFT storage as a strategy to prolong the shelf life of peach fruit, reduce post-harvest losses, and maintain fruit quality could be highlighted. Furthermore, any study limitations and avenues for future research could be addressed to provide a more balanced and informative conclusion.
Author Response
Dear Editor and Reviewer,
Thank you very much for giving us an opportunity to revise our manuscript entitled “Near-freezing temperature storage improves peach fruit chilling tolerance by regulating the antioxidant and proline metabolism” (horticulturae 2918394).
We have revised our manuscript carefully according to the comments, and would like to re-submit it for your consideration. The amendments are highlighted in yellow color in the revised manuscript. Our responses to the referees are listed by point to point in the following sections.
We would like to express our great appreciation to you and reviewer for the comments and hope that revised manuscript is acceptable.
Look forward to hearing from you.
Yours sincerely,
Dr. Handong Zhao
Reply to Referee 2
The comments and suggestions from you are very valuable. Our revised portions according to the reviewer's comments are listed as following.
To Referee 2
Comment 1: Parameters like texture and colour should be evaluated: It would enhance the study's comprehensiveness to include evaluations of texture and colour changes in the peach fruit samples.
Response: Thank you for your advice. I also believe that the evaluation of color and texture is very important for test the quality of fresh fruit. However, this research mainly focused on the effect of antioxidant and proline metabolism on chilling tolerance induced by NFT storage in peach fruit. For the colour analysis, I have done some work in my previous research (Zhao et al, 2018). For the texture research, I would like to pay more attention in the future research, especially on the micro-structure and related regulatory mechanism.
Cited reference --Zhao, H., Shu, C., Fan, X., Cao, J., & Jiang, W. (2018). Near-freezing temperature storage prolongs storage period and improves quality and antioxidant capacity of nectarines.Scientia Horticulturae,228, 196-203.
Comment 2: Please, improve the conclusion section.
Response: Thank you for your advice. I have revised this section as “In conclusion, the study highlights intriguing findings regarding the efficacy of NFT storage in mitigating chilling injury in peaches, especially when compared to storage at higher temperatures. Notably, NFT storage exhibited a consistent preservation of elevated levels of antioxidant enzyme activities, ascorbic acid, phenolics, and DPPH scavenging capacity. It effectively mitigated the accumulation of malondialdehyde and inhibited the activity of proline dehydrogenase (PRODH). Additionally, NFT storage facilitated increased proline production and bolstered the overall antioxidant defense system.”, which has been marked in conclusion of revised manuscript.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe authors have addressed all of my questions. I have no further remarks. I recommend accepting the manuscript in its current state.
Comments on the Quality of English LanguageMinor editing of English language required
