Exogenous Melatonin as Pre- and Postharvest Application on Quality Attributes, Antioxidant Capacity, and Extension of Shelf Life of Papaya

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript investigated the effects of pre and postharvest melatonin (EMT) application on the quality and antioxidant enzyme activities and postharvest senescence of papaya during both ambient (32 ± 2°C and 55 ± 5% RH) and cold storage (10°C± 2°C and 90-95% RH). However, But some methodologies and discussion are not scientific and reasonable, following suggestions should be considered in order to improve the quality of this paper:

1. Although the screening experiment about optimum application concentration during pre or postharvest stage alone was done previously, but the function of melatonin treatment during pre or postharvest stage is diffrent, so pre or postharvest treatment alone at optimum application concentration should added in this study to confirm that control effect of compound treatment was better than those of pre and postharvest alone.  

2. Line 33: the authors described “.....effective in prolonging shelf life”, please provide related comperimental data.

3. Line 35: “improved firmness” should change as “kept or maintained firmness”.

4. the differences of control effect between treatments in Figure 6 were not significant.

5. the possible control mechanism of melatonin application, especially during pre-harvest should comprehensively discussed.

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The study demonstrated exogenous melatonin as pre and postharvest application on quality attributes, antioxidant capacity and extension of shelf life of papaya, while the research conducted is comprehensive, the writing and layout require attention to enhance readability. Here are the recommended improvements, tailored to the specific points mentioned:

 

1. For Abstract: the abstract can not contain what you have done, the “preharvest” should be included, while “delay senescence and postharvest storage”, can be just left one.

2. Line 131: Provide a more detailed account of how the spraying treatment was administered.

3. Eliminate unnecessary repetition of treatment details (Lines 269-276 & 279-286): Streamline the description of treatment details to avoid repetition and make the section more concise.

4. Use "Pectin Methyl Esterase (PME)" consistently throughout the text. Ensure that the abbreviation is introduced before it is used for the first time (e.g., Line 157).

5. Improving the layout and formatting of figures. All the firgures seem to be arranged poorly.

(1) Increase the font size of text within figures to improve readability.

(2) Adjust the positioning of y-axis labels to avoid overlap with the axis itself.

(3) Add statistical significance markers (e.g., asterisks) to indicate differences between groups.

(4) Clarify figure captions, particularly for Fig. 1, which should distinguish between subfigures       A, B, and potentially C, D (if applicable), and ensure 'P' in P<0.05 is italicized.

(5) Address similar issues in Fig. 2, and consider organizing Fig. 3 into a two-column, three-row format for better visibility.

(6) Separate figure legends from Fig. 6 to prevent overlap, and ensure Fig. 7 does not cover its legend.

Comments on the Quality of English Language

English can be improved.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Please find below my suggestions:

-L53-L55: rephrase the sentence "severely.... several...";

-L56; L60: please do not repeat "severely"  and "several" in each sentence, change it;

-L83: please correct "signalling" with "signaling"

-L125: please describe how many fruits were treated in pre-harvest and post-harvest experiments

-L146: how many fruits were used for the weogh loss measurements? add this information in the text

-L331: add the legend of the treatments in all the caption of the figures, you put it in the tables and you forget it in the figures.

-L332: L442: I don't underdstand why you choose only two treatments (T1 and T2) to measure the respiration rate and texture and not all the treatments, please explain it.

Comments on the Quality of English Language

The manuscript require minor editing of English language.

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors addressed all the issues raised and improved the clarity and quality of the manuscript. I agree with the changes that were introduced in the manuscript. Therefore, I recommend that the manuscript can be published in its current form.