After-Effect of Biogas Digestate Used for Growing Seedlings on the Antioxidant System of Tomato (Solanum lycopersicum) Fruits

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

1. Line 15, what does 15-20% share mean, no exact definition.
2. Line 19, which means that it prepared for analyses with methanol.
3. Complete the keywords.
4. The methodology should be supplemented with the type of digestate, the content of macro and micro elements in the soil in the blank and test sample, the method of determining the degree of maturity, the content of fiber content and fiber composition and content of elements in fruits.
5. Tables 1, 2, 3 and 4 should be simplified, some information can be presented in the text, it should be specified whether the demonstrated significance applies to columns or rows?
6. Table 5 is not understandable in terms of the presented data, if these are average values ​​for previously conducted tests, I suggest placing them in earlier tables.
7. As part of the proposed supplements to the analyses of the tested material, other correlations relating to antioxidant properties can be found.
8. The abbreviations used should be corrected, as well as Fig. 1 - it is illegible.

Author Response

We sincerely appreciate your work and valuable feedback. Your comments have significantly improved the quality of the manuscript, and we are truly grateful. We have made every effort to address your suggestions and revise the manuscript accordingly. Below, you will find our responses to your comments.

Comments 1: Line 15, what does 15-20% share mean, no exact definition.

Response 1: The information has been revised and improved.

Comments 2: Line 19, which means that it prepared for analyses with methanol.

Response 2: The information has been revised and corrected.

Comments 3: Complete the keywords.

Response 3: Completed

Comments 4: The methodology should be supplemented with the type of digestate, the content of macro and micro elements in the soil in the blank and test sample, the method of determining the degree of maturity, the content of fiber content and fiber composition and content of elements in fruits.

Response 4: Peat substrate (N 100 – 120, P₂O₅ 30–80, K₂O 120–200 mg L^-1; microelements Fe, Mn, Cu, S, Mo, Zn; pH 5.5–6.5) (Profi 1, Durpeta, Lithuania); Feedstock for digestate production: grains and corn (LTD “Kurana”). Chemical composition of digestate: 18.51 % organic matter, 0.406% Total Nitrogen (N), 1.81% Phosphorus (P₂O₅), 0.241% Potassium (K₂O), pH 6.4.

From the data of this study, we see the potential for further research, unfortunately, we do not currently have more fruit quality data, but we see that this is important research and we will seek to deepen and expand the research on the effect on fruit quality.

Comments 5: Tables 1, 2, 3 and 4 should be simplified, some information can be presented in the text, it should be specified whether the demonstrated significance applies to columns or rows?

Response 5: Tables were revised.

Comments 6: Table 5 is not understandable in terms of the presented data, if these are average values ​​for previously conducted tests, I suggest placing them in earlier tables.

Response 6: The table was deleted and added yield results.

Comments 7: As part of the proposed supplements to the analyses of the tested material, other correlations relating to antioxidant properties can be found.

Response 7: The results and discussion sections have been supplemented and revised.

Comments 8: The abbreviations used should be corrected, as well as Fig. 1 - it is illegible.

Response 8: The abbreviations used was corrected, as well as Figure 1 (now Figure2)

Reviewer 2 Report

Comments and Suggestions for Authors

The article entitled “Biogas digestate used for seedling production after-effect on the antioxidant system of tomato (Solanum lycopersicum) fruits” is a short paper mainly focusing on using biogas digestate for seedling production of tomatoes. It is an interesting read but the authors have to revise it before formal acceptance in the journal.

The title seems confusing and not grammatically correct.

The authors used the term seedlings however no data on seedlings is provided.

In materials and methods section, no data regarding growth conditions is provided. Moreover the design used is not clearly explained. Section 2.1 and 2.2 need to be combined and revised properly under one heading “Growth conditions and Sample collection”.

In tables, the F-value isn’t provided, the authors only presented the significance level with asterisks.

Some sentence e.g. in Tables…….effect of digestate and maturity………………..what the authors means with maturity……………the design is focusing on the seedlings growth and fruits production influenced with digestate biogas.

Phenotypic data is also missing to support the results.

Comments on the Quality of English Language

English needs to be improved.

Author Response

We sincerely appreciate your work and valuable feedback. Your comments have significantly improved the quality of the manuscript, and we are truly grateful. We have made every effort to address your suggestions and revise the manuscript accordingly. Below, you will find our responses to your comments.

Comments 1: The title seems confusing and not grammatically correct.

Response 1: The title was revised

Comments 2: The authors used the term seedlings however no data on seedlings is provided.

Response 2: The term seedlings is used because the digestate was used only for growing seedlings, and the persistent effect on fruits was studied. We tried to present this as clearly as possible in the manuscript. Taking into account the comments, we revised the manuscript and its methodological part again, trying to present all the information as clearly as possible.

Comments 3: In materials and methods section, no data regarding growth conditions is provided. Moreover the design used is not clearly explained. Section 2.1 and 2.2 need to be combined and revised properly under one heading “Growth conditions and Sample collection”.

Response 3: The materials and methods section was revised. Lines 106-109 provide growing conditions

Comments 4: In tables, the F-value isn’t provided, the authors only presented the significance level with asterisks.

Response 4: In order to minimize the burden of additional figures in the manuscript, after reviewing the presentation methods of other scientists, we chose to present only significant levels. The results of the statistical analysis show that all variants are <0.001.

 

Comments 5: Some sentence e.g. in Tables…….effect of digestate and maturity………………..what the authors means with maturity……………the design is focusing on the seedlings growth and fruits production influenced with digestate biogas.

Response 5: We tested tomatoes at different maturity levels ( 80-100% typical size – BBCH 70 – 79 (a), 40-50% ripeness – BBCH 84 – 85 (b), and 100% ripeness – BBCH ). The manuscript has been revised for language structure and other errors, we hope it has become clearer.

Comments 6: Phenotypic data is also missing to support the results.

Response 6: We have supplemented the results with yield data, which is relevant in terms of fruit quality and antioxidants.

Reviewer 3 Report

Comments and Suggestions for Authors

Dear Authors,

congratulations on your work! However, I believe some aspects need improvement. Specifically, I would like to ask why the biomorphometric parameters of the plants were not measured.

Additionally, there are no data on production yield or its components, such as the number of marketable fruits and waste per plant.

This seems to be a significant limitation for this research.

Could you please clarify this?

Furthermore, I noticed that some of the references are outdated; they should be updated.

Best regards,  
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Author Response

We sincerely appreciate your work and valuable feedback. Your comments have significantly improved the quality of the manuscript, and we are truly grateful. We have made every effort to address your suggestions and revise the manuscript accordingly. Below, you will find our responses to your comments.

Comments 1: Specifically, I would like to ask why the biomorphometric parameters of the plants were not measured.

Response 1: This manuscript focuses on the long-term effects of digestate on the fruit quality parameters of seedlings, we will not emphasize the impact of digestate on seedling quality in this study. However, seedling quality was assessed from various aspects, and a lot of data was collected, although the differences at the seedling stage were not very pronounced.

Comments 2: Additionally, there are no data on production yield or its components, such as the number of marketable fruits and waste per plant.

This seems to be a significant limitation for this research.

Could you please clarify this?

Response 2: We supplemented the manuscript with data on yield per plant, total, marketable, and waste.

Comments 3: Furthermore, I noticed that some of the references are outdated; they should be updated.

Response 3: References were reviewed for relevance. Old references were retained that indicate analytical methods or other information relevant to the manuscript. We try to provide an overview of the latest research and its results.

Reviewer 4 Report

Comments and Suggestions for Authors

The authors of the manuscript titled "Biogas Digestate Used for Seedling Production: After-Effects on the Antioxidant System of Tomato (Solanum lycopersicum) Fruits" investigated the effects of solid digestate used in seedling production on the antioxidant capacity of tomatoes at three maturity stages: green, half-ripe, and fully ripe. The findings revealed that the incorporation of 20% digestate significantly enhanced antioxidant activity and total phenol content in both green and half-ripe fruits. In contrast, fully ripe fruits demonstrated a consistent antioxidant response across all digestate treatments.

Introduction:

L41-43: Citation needed.

L54-55: ‘Different proportions of digestate impact tomato growth, yield, and fruit quality.’ Please provide more details on how digestate influences the growth, yield, and fruit quality of tomatoes.

L78: Please provide information on the chemical composition of digestate.

Materials and Methods:

L88: variety Brooklyn instead of variety “Brooklyn” (Please correct it throughout the text).

L92: Please indicate the source of the seeds.

L99-100: Did the authors observe any differences in the growth characteristics of tomato seedlings among the treatments?  Please indicate the quality of seedings for better understanding.

L101: Please indicate the age of the seedlings.

L113: Please provide the harvesting dates and a photograph showing the maturity stages of tomatoes.

L118: Why do the authors overlook important antioxidants in tomatoes, such as ascorbic acid, carotenoids, and flavonoids?  

The composition and content of phenolics in tomatoes harvested from each treatment should be analyzed and presented. This data will provide a clearer understanding of the quality of the tomato fruits and the role of individual phenolics on fruit maturity.

Results:

L238: Please improve the quality of Figure 1.

Discussion:

L263: ‘This consistent treatment minimized stress on the plants and clarified the relationship between seedling quality and subsequent harvest quality.’  Please provide data, such as hydrogen peroxide content or Fv/Fm ratio, to assess stress levels and also seedling quality.

L304: Donald instead of “Donald”

L306: Naomi

L317: Marmande-Cuarenteno (please correct it for other cultivars)

L329-361: Please describe the differences in nutrient composition among the various digestate treatments and discuss how these differences impact the quality of tomatoes. Additionally, relate this discussion to the authors' statement in Line 261, which indicates that uniform fertilization and care were provided for all variants after transplantation into the greenhouse.

 

 

 

Comments on the Quality of English Language

The authors should improve the quality of English text for better understanding.

Author Response

We sincerely appreciate your work and valuable feedback. Your comments have significantly improved the quality of the manuscript, and we are truly grateful. We have made every effort to address your suggestions and revise the manuscript accordingly. Below, you will find our responses to your comments.

Comments 1: L41-43: Citation needed.

Response 1: Thank you for the notice, the citation was added.

Comments 2: L54-55: ‘Different proportions of digestate impact tomato growth, yield, and fruit quality.’ Please provide more details on how digestate influences the growth, yield, and fruit quality of tomatoes.

Response 2: Information was added.

Comments 3: L78: Please provide information on the chemical composition of digestate.

Response 3: We present the characteristics of the digestate we studied in the methodology section:

Feedstock for digestate production: grains and corn (LTD “Kurana”). Chemical composition of digestate: 18.51 % organic matter, 0.406% Total Nitrogen (N), 1.81% Phosphorus (P₂O₅), 0.241% Potassium (K₂O), pH 6.4.

Comments 4:  L88: variety Brooklyn instead of variety “Brooklyn” (Please correct it throughout the text).

Response 4: Thank you. Corrected.

Comments 5:  L92: Please indicate the source of the seeds.

Response 5: Information added.

Comments 6:  L99-100: Did the authors observe any differences in the growth characteristics of tomato seedlings among the treatments?  Please indicate the quality of seedings for better understanding.

Response 6:   The seedlings were transferred to the greenhouse 44 days after sowing. We have supplemented the methodologies with important information. Since this manuscript focuses on the long-term effects of digestate on the fruit quality parameters of seedlings, we will not emphasize the impact of digestate on seedling quality in this study. However, seedling quality was assessed from various aspects, and a lot of data was collected, although the differences at the seedling stage were not very pronounced.

Comments 7:  L101: Please indicate the age of the seedlings.

Response 7:   The seedlings were transferred to the greenhouse 44 days after sowing. We have supplemented the methodologies with important information.

Comments 8:  L113: Please provide the harvesting dates and a photograph showing the maturity stages of tomatoes.

Response 8: Information added.

Comments 9:  L118: Why do the authors overlook important antioxidants in tomatoes, such as ascorbic acid, carotenoids, and flavonoids?   The composition and content of phenolics in tomatoes harvested from each treatment should be analyzed and presented. This data will provide a clearer understanding of the quality of the tomato fruits and the role of individual phenolics on fruit maturity.

Response 9: We agree that the data you mention would be significant in expanding and deepening the essence of our research. From the data of this study, we see the potential for further research, unfortunately, we do not currently have more data, but we see that this is important research and we will seek to deepen and expand the research on the effect on antioxidants and fruit quality.

Comments 10:  L238: Please improve the quality of Figure 1.

Response 10: We improved the quality of the figure as much as we could.

Comments 11:   L263: ‘This consistent treatment minimized stress on the plants and clarified the relationship between seedling quality and subsequent harvest quality.’  Please provide data, such as hydrogen peroxide content or Fv/Fm ratio, to assess stress levels and also seedling quality.

Response 11: This part of the discussion has been edited to remove misunderstandings and unsupported results.

Comments 12:   

L304: Donald instead of “Donald”

L306: Naomi

L317: Marmande-Cuarenteno (please correct it for other cultivars)

Response 12:  Corrected

Comments 13:   L329-361: Please describe the differences in nutrient composition among the various digestate treatments and discuss how these differences impact the quality of tomatoes. Additionally, relate this discussion to the authors' statement in Line 261, which indicates that uniform fertilization and care were provided for all variants after transplantation into the greenhouse.

Response 13: The discussion was revised and supplemented.

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

In my opinion, this article can be published in its current form.

Author Response

We are very grateful for your comments and help in improving our manuscript.

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have substantially revised the paper according to my previous comments.

Author Response

We are very grateful for your comments and help in improving our manuscript.

Reviewer 3 Report

Comments and Suggestions for Authors

Dear authors, congratulations!

Your paper has been significantly improved and is now acceptable for publication.

Best regards

Author Response

We are very grateful for your comments and help in improving our manuscript.

Reviewer 4 Report

Comments and Suggestions for Authors

The authors have successfully addressed most of the comments. 

Author Response

We are very grateful for your comments and help in improving our manuscript.