Review Reports - Salicylic Acid Modulates Okra Tolerance to Salt Stress in Hydroponic System

Round 1

Reviewer 1 Report

The present represents the effect of salicylic acid on okra under slat stress in the hydroponic system. The study is interesting however few modifications can make this study more valuable.

It would be much better if the image in Fig.2 would present the effect of salicylic acid vs. salt and control (treated). the present image does not show any salt or salycylic acid treatment.

The description of prabability level etc must be written below the figure description/caption. "P" of significance level is written in italic, please make correct.

The conclusion is very vague. write a concise conclusion.

Author Response

Campina Grande, PB

Oct. 7, 2022

Reference: Agriculture 1954372 – Review Report

Dear Editor

The authors are very grateful to you and the Reviewers for the positive and constructive comments and suggestions on our manuscript entitled “Salicylic acid modulates okra tolerance to salt stress in a hydroponic system”. The authors would like to inform you that a thorough revision of the manuscript was made, incorporating the suggestions and adapting the text according to the comments. Attached is the revised version of the manuscript. All changes are highlighted in red.

The authors would like to express their great appreciation for the comments on our article and remain at your disposal for any further information and explanation.

The responses/clarifications to the issues raised by the Reviewers/Editor are presented below:

REVIEWER 1

The present represents the effect of salicylic acid on okra under slat stress in the hydroponic system. The study is interesting however few modifications can make this study more valuable.

Comentário 1: It would be much better if the image in Fig.2 would present the effect of salicylic acid vs. salt and control (treated). the present image does not show any salt or salycylic acid treatment.

Response: The insertion of Fig. 2 did not aim to show the effect of salicylic acid and the control treatment, it was inserted to demonstrate how the hydroponic cultivation of okra was mounted and the crop growth in different phases (vegetative, flowering, and production).

Comentário 2: The description of prabability level etc must be written below the figure description/caption. "P" of significance level is written in italic, please make correct.

Response: Suggestion was accepted and inserted in the revised manuscript.

Comentário 3: The conclusion is very vague. write a concise conclusion.

Response: Conclusions were adapted as per suggestions of the Reviewers.

Geovani Soares de Lima

Corresponding Author

Author Response File: Author Response.docx

Reviewer 2 Report

The title of the research paper, "Salicylic acid modulates okra tolerance to salt stress in the hydroponic system," is appropriate.

Abstract: Needs to improve by adding some words and data regarding the yield improvement with the application of Salicylic acid

Introduction: The introduction correctly places the study in the context with an appropriate statement of the purpose of the study. The description of the working hypothesis and studies referring to the yield improvement using Salicylic acid should be added.

Methodology and Results: Experiment I & Experiment II were described clearly; however, the authors did not mention how many times both the treatments were replicated. How many plants were taken into account for data recording regarding yield? How were the two different treatments different in terms of Okra yield? How the yield obtained was compared (control treatment is missing). Obtaining improved yield and reducing losses was the study's main objective, but this component is not clearly described. Moreover, some unnecessary statistical analyses have been used in the study. The results section shows data regarding the yield obtained, number of plants used, control experiment, yield comparison, and effect of both treatments on the yield.

It is also an important question: Why did the authors use only one hybrid cultivar? Why didn't they compare and analyze the other cultivars for their performance in the given environment to select and recommend the best one for cultivation under a hydroponic system?

Discussion: Must be improved keeping in view the above discussion.

Author Response

Campina Grande, PB

Oct. 7, 2022

Reference: Agriculture 1954372 – Review Report

Dear Editor

The authors would like to express their great appreciation for the comments on our article and remain at your disposal for any further information and explanation.

The responses/clarifications to the issues raised by the Reviewers/Editor are presented below:

REVIEWER 2

The title of the research paper, "Salicylic acid modulates okra tolerance to salt stress in the hydroponic system," is appropriate.

Comentário 1: Abstract: Needs to improve by adding some words and data regarding the yield improvement with the application of Salicylic acid

Response: The abstract was adjusted in the revised version of the manuscript, inserting the contexto/problem of the study and also taking into account the norms of the Journal (maximum of 200 words).

Comentário 2: Introduction: The introduction correctly places the study in the context with an appropriate statement of the purpose of the study. The description of the working hypothesis and studies referring to the yield improvement using Salicylic acid should be added.

Response: The description of the hypothesis was inserted in the revised version of the manuscript, as can be seen between lines 78 and 81.

Comentário 3: Methodology and Results: Experiment I & Experiment II were described clearly; however, the authors did not mention how many times both the treatments were replicated. How many plants were taken into account for data recording regarding yield? How were the two different treatments different in terms of Okra yield? How the yield obtained was compared (control treatment is missing). Obtaining improved yield and reducing losses was the study's main objective, but this component is not clearly described. Moreover, some unnecessary statistical analyses have been used in the study. The results section shows data regarding the yield obtained, number of plants used, control experiment, yield comparison, and effect of both treatments on the yield.

Response: As can be seen in Item 2.1 (Location of the experiment) of the revised version of the manuscript, each experiment was conducted once. The Experiment I was conducted between October and December 2021 (under conditions of relatively higher temperatures) and Experiment II between January and March 2022 (under conditions of relatively milder temperatures), the pertinente data presented in Figure 1.

In Item 2.2 (Treatments and experimental design) it is mentioned that both experiments (Experiments I and II) had 16 treatments (4×4) with four replicates and two plants per plot, that is, for the analysis of productivity, as well as for the other traits studied, in all 128 plants were considered in each experiment.

As can be seen in the revised version of the manuscript (Item 2.2), in Experiment I, the control treatment was EC = 2.1 dS m^-1 with salicylic acid (SA) = 0 mM, while in Experiment II, the control treatment was EC = 3.0 dS m^-1 with SA = 0 mM.

The statistical analysis used in both experiments were necessary, to obtain the correct information and followed the methodologies described in Item 2.6.

Comentário 4: It is also an important question: Why did the authors use only one hybrid cultivar? Why didn't they compare and analyze the other cultivars for their performance in the given environment to select and recommend the best one for cultivation under a hydroponic system?

Response: The analysis of the performance of okra cultivars was not part of the objectives of this research, and for this reason, this was not included. The authors agree with the Reviewer that the performance of okra cultivars under salt stress is an important aspect and must be studied in the future with priority. However, the objective of the present study was limited to evaluating the effect of foliar application of salicylic acid concentrations in mitigating the effects of saline stress on 'Canindé' okra cultivation in the NFT (Nutri-ent Film Technique) hydroponic system.

Comentário 5: Discussion: Must be improved keeping in view the above discussion.

Response: The discussion has been adapted according to the suggestions of the other reviewers, as well as taking into account the issues raised above.

Geovani Soares de Lima

Corresponding Author

Author Response File: Author Response.docx

Reviewer 3 Report

The article introduces a good and hard work. But If you worked in green house, You should mention the environmental conditions inside the house and there is no need to outside weather conditions.

There some suggestions I offered in the flyer.

The statistical design should be changed.

In my mind, I think you should merge the two experiment in one, as the salinity levels are almostly the same.

Comments for author File: Comments.pdf

Author Response

Campina Grande, PB

1º de outubro de 2022

Referência: Agricultura 1954372 – Relatório de Revisão

Editor Caro

The authors would like to express their great appreciation for the comments on our article and remain at your disposal for any further information and explanation.

The responses/clarifications to the issues raised by the Reviewers/Editor are presented below:

Comentário 1: What is that mean???? Write it in full name as it is the first abbreviation...sn or ns?

Response: Instead of ECns or ECsn (electrical conductivity of nutrient solution) in the revised manuscript, the authors opted for EC (Lines 23 and 24); and the same has been corrected at all places in the text.

Comentário 2: 2.3 or 2.4??

Response: Estimated concentration of 2.3 mM salicylic acid according to the equation.

Comentário 3: Increase or reduction?

Response: The excess of salts present in the soil and/or water reduces the osmotic and water potential, making them more negative.

Comentário 4: You should add a paragraph regards to the types of hydroponic system and NFT type.

Response: The suggestion was accepted and a new paragraph was inserted in the revised manuscript, as can be seen between Lines 53 and 57.

Comentário 5: Where is the control treatment?

Response: The information is inserted in the revised version of the manuscript. In the first experiment, the control treatment was EC = 2.1 dS m^-1 and SA = 0 mM. While in the second experiment, the control was EC = 3.0 dS m^-1 and SA = 0 mM.

Comentário 6: These are two statistical different designs? Please split block is the correct one...?

Response: The statistical design adopted in the two experiments was the same, that is, a completely randomized design was used in a split-plot scheme, with the electrical conductivity levels of the nutrient solution (EC) being considered the plots and salicylic acid (SA ), the subplots.

Comentário 7: AS or SA? Please fix it in all the text

Response: Sorry for the inconvenience. The correct is SA (salicylic acid). This acronym was checked throughout the text in the revised version of the manuscript and corrected.

Comentário 8: It is almost the same levels in the former experiment..... 9.0 dS/m is the only change and you can add it to the first one.

Resposta: Foi feita uma tentativa de analisar os resultados de ambos os experimentos juntos. Infelizmente, isso não foi considerado plausível devido ao aumento do coeficiente de variação ocorrido na análise conjunta. Embora os níveis de condutividade elétrica da solução nutritiva tenham sido semelhantes, o tempo de condução dos experimentos foi diferente. No segundo experimento (janeiro a março), em comparação ao Experimento I (outubro a dezembro), as temperaturas foram mais baixas e a umidade relativa do ar maior do que o Experimento I, fato que até reduziu o ciclo da cultura (77 dias).

Comentário 9: As informações do equipamento devem ser adicionadas.

Resposta: As informações sugeridas foram inseridas na versão revisada do manuscrito, conforme pode ser observado entre as linhas 145 e 146.

Author Response File: Author Response.docx

Reviewer 4 Report

Please, remove unnecessary text from the abstract and results. Some tables are not transparent, i.e. it is difficult to follow the results with a lot of abbreviations. Also, some of results are repeated in the discussion. Please, avoid writing in the first person plural in some parts of the text. Refine the conclusions... the authors can certainly write it better.

Comments for author File: Comments.pdf

Author Response

Campina Grande, PB

1º de outubro de 2022

Referência: Agricultura 1954372 – Relatório de Revisão

Caro editor

The authors would like to express their great appreciation for the comments on our article and remain at your disposal for any further information and explanation.

The responses/clarifications to the issues raised by the Reviewers/Editor are presented below:

REVIEWER 2

Comentário 1: ECns- it can only be stated „ EC“.

Response: The suggestion was accepted in the revised version of the manuscript, throughout the text the acronym ECns was replaced by EC.

Comentário 2: The second experiment differed from the first only by the increase in the ECns levels … Why?

Response: Yes, the second experiment differed from the first only in terms of EC levels. Thus, we sought to assess the tolerance of okra to higher levels of EC (7.0 and 9.0 dS m-1) and analyze the efficacy of salicylic acid concentrations to minimize the harmful effects caused by an increase in salinity and validation of results at different times.

Comentário 3: Previously was stated otherwise (ECsn)... please use inly EC.

Response: As mentioned earlier, the correct acronym is EC, the entire text has been checked and corrected where ever necessary.

Comentário 4: Please, remove unnecessary text from the abstract.

Response: The text was removed in the revised version of the manuscript, as suggested.

Comentário 5: In which concentrations SA is applied? … So that later in the Materials and methods you can explain why you used the specified concentrations.

Response: Information on the concentrations of salicylic acid used was inserted in the revised version of the manuscript, as can be seen in Line 66.

Comentário 6: Newer rules state that it is not necessary to write Latin family names in italics.

Response. The suggestion was accepted, and the italics were removed.

Comentário 7: Why okra in NFT system? Are the costs of production in this way in Brazil covered by the yield and extension of market supply?

Resposta: The hydroponic system of the NFT type (laminar flow of nutrients), is characterized by being a closed system and recirculation of the nutrient solution stands out for having proven economic viability, being the most used in the cultivation of fast-growing vegetables, such as okra. This information has been inserted in the revised version of the manuscript, as can be seen between Lines 53 and 57.

Comentário 8: Please specify the duration of the first and second experiment.

Response. The suggestion was accepted and inserted in the revised version of the manuscript. The first experiment was conducted from October to December 2021, and the second between January and March 2022.

Comentário 9: It is not necessary to specify separately… so please move this cultivar description to … Line 126 - Sowing was carried out in 50 mL polyethylene containers containing.

Response. The suggestion was accepted and the text moved to the indicated line, as can be seen in the revised version of the manuscript (Line 154).

Comentário 10: In Figure 1, please also indicate the mean temperature, as it indicates a deviation from the optimal ones for okra phenophases.

Response. Suggestion accepted. Accordingly, Figure 1 was adapted by inserting the mean temperature data observed inside the greenhouse during the experiments.

Comentário 11: The nutrient solution was prepared according to the recommendation of Hoagland [24].

Response. Correction inserted in the revised version of the manuscript.

Comentário 12: It would be more clearly to show the amount of salts for preparing the solution in a table.

Response. The suggestion was accepted, and the information regarding the quantity of salts used in the preparation of the nutrient solution was entered in a table (Table 1).

Comentário 13: Sponges – please state supplier or producer.

Response. The plant sponges were not purchased through a supplier or producer. The sponge was obtained from the fruit of the loofah (Luffa aegyptiaca), which can be used as a support matrix for plants grown in hydroponics, other species in the genus Luffa also provide plant sponges, but the species Luffa aegyptiaca is the one that presents varieties that produce better quality sponges and is the most cultivated species in the world for this purpose.

Comentário 14: In both experiments was the same? 60 days?

Response. Yes, in both experiments these analysis were performed 60 days after transplanting.

Comentário 15: Number of harvest? i.e. how many times the harvest was carried out?

Response. Five harvests were performed at two-day intervals. This information was inserted in the revised version of the manuscript.

Comentário 16: I suggest to correct table titles. Also it is difficult to follow the results with a lot of abbreviations.

Response. As suggested by the reviewers/editor, the analysis of variance tables were removed from the revised version of the manuscript. In addition, the abbreviations of the response variables were substituted, inserting the full name.

Comentário 17: Why so much increase in EC value.

Response. The increase in electrical conductivity of the nutrient solution aimed to analyze the tolerance of hydroponic okra to higher saline levels (9.0 dS m^-1) to determine its threshold salinity in hydroponic cultivation.

Comentário 18: Dados não mostrados.

Resposta. As informações referentes à temperatura média foram inseridas na versão revisada do manuscrito, conforme pode ser observado na Figura 1.

Geovani Soares de Lima

Autor correspondente

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

Suggestoins incorporatoin is satisfactory, the research article can be published in its present form now.

Author Response

The authors would like to express their great appreciation for the comments on our article and remain at your disposal for any further information and explanation.

Author Response File: Author Response.pdf