Application Methods of Zinc Sulphate Increased Safflower Seed Yield and Quality under End-Season Drought Stress

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript is well-written, has relevance, and follows the scientific method. My main concern is the statistical analysis, which seems a bi- or even a tri-factorial, but was analyzed as a one-way ANOVA. I suggest re-analyzing the statistics, performing the unfolding of each factor, and also checking the interaction between factors. Further comments and suggestions were made in the revised PDF version, and are presented below:

 

- Abstract:

Line 16: Please, add the number of days after sowing in which the irrigation was interrupted. For example: (XX-XX days after sowing).

Line 25: correct to “higher than in the first year”.

Line 29: add “application” before “methods”.

Line 30: replace “its” by “phosphorus”.

 

- Introduction:

Line 45: This reference does not bring the cited information. Please, replace by the correct citation.

Line 51-55, 66-68, 69-72, 72-73, 77-79, 90-92, 101-102, 561-562: Please, provide a citation for these sentences.

Why the study “Improvement in seed quantity and quality of spring safflower through foliar application of boron and zinc under end-season drought stress” is not mentioned in your manuscript? It evaluated zinc sulphate in safflower too. (https://doi.org/10.1080/01904167.2019.1584214).

 

- Materials and Methods:

Line 119, 126, and 128: The number of days after sowing or after planting must be stated here.

Line 119: Also, add how many days the irrigation interruption lasted.

Line 121: Why did authors choose these zinc concentrations? Was it based in the literature? If so, cite the references. Please, specify.

How leaf sprays were applied? Hand sprays? What was the volume/flow rate applied?

Line 137: Please, standardize the way you cite numbers and units. I suggest using 4 m here.

Line 139: Use "m" instead of "meter".

Lines 156-158: Remove extra lines.

Table 1 and 2 were wrongly placed in the file.

Table 1: Please, express the units as dS m^-1 and mg kg^-1

 

- Results:

As authors used different factors, the correct would be to use a two-way ANOVA instead of one-way. This way, lowercase letters would compare treatments (control, SA, SR… etc), while capital letters would compare normal with stress. Moreover, the two years must be analyzed separately, not comparing one to another. If you really want to compare 2016 with 2017, you can consider year as another factor (trifactorial) and use another symbol could be used to indicate significant differences (for example # or *). In this context, a table with the summary of ANOVA must be provided as supplementary material.

Figures 1 with 2; and 3 with 4 must be placed together.

Fig. 3: Please correct kg/ha to kg ha^-1

- Discussion:

In general, discussion is well written.

Lines 561-562: Please, provide a citation for these sentences.

 

- Conclusions:

Please, do not use acronyms in the conclusion.

Include two short sentences in the end of conclusion: the first stating which method and dose were the best option; and the second stating the importance of this finding.

Comments for author File: Comments.pdf

Author Response

Reviewer 1:

The manuscript is well-written, has relevance, and follows the scientific method. My main concern is the statistical analysis, which seems a bi- or even a tri-factorial, but was analyzed as a one-way ANOVA. I suggest re-analyzing the statistics, performing the unfolding of each factor, and also checking the interaction between factors. Further comments and suggestions were made in the revised PDF version, and are presented below:

Authors: The respected Reviewer 1 had a question about the statistical analysis method at the beginning, which was answered in the results section.

- Abstract:

Line 16: Please, add the number of days after sowing in which the irrigation was interrupted. For example: (XX-XX days after sowing).

- Authors: the number of days after sowing was added to the abstract.

 - Authors: Line 18: "without zinc sulfate" changed to "no zinc sulfate".

Line 25: correct to “higher than in the first year”.

- Authors:  "more than" changed to "higher than".

Line 29: add “application” before “methods”.

Authors: it was done.

Line 30: replace “its” by “phosphorus”.

Authors: it was done.

-Line 31: Authors:  "Although" was removed from the sentence.

 -Line 45: the reviewer stated to change Vazayefi et al. (2023) with the other reference.

Authors: Although the sentence written in the text of the manuscript was clearly mentioned in this article, this article was replaced by the article of "Mirzabaev et al. (2023)".

Line 51-55, 66-68, 69-72, 72-73, 77-79, 90-92, 101-102, 561-562: Please, provide a citation for these sentences.

 - Authors: The references of sentences of lines 51-55, were wrote in the end of the sentence in line 56 as [4,5].

The reference of sentences of lines 66-68 is [8].

The references of sentences of lines 69-72 and 72-73 is [9].

The references of sentences of lines 77-79 is [11].

The references of sentences of lines 90-92 is [11].

A reference was added for the sentence of lines 101-102.

The references of sentences of lines 561-562 are [9,13,25].

In lines 85 and 95, the respected reviewer has recommended that reference [11] be removed and research articles be used instead of a reference book.

Authors: The reference used with number 11 (Mineral Nutrition of Higher Plants) is a very reliable book that is used as a reference book in many universities around the world. The reason for not accepting this reference by the respected reviewer was not clear to the authors. Why does the respected reviewer not accept this reference book and insist on using a research paper? It is necessary to say, this reference is explained and mentioned in the introduction section where the general principles are explained. On the other hand, if a reference book is not worth including in an article, then where should it be used? Is a reference book invalid? Therefore, this reference was not changed.

Why the study “Improvement in seed quantity and quality of spring safflower through foliar application of boron and zinc under end-season drought stress” is not mentioned in your manuscript? It evaluated zinc sulphate in safflower too. (https://doi.org/10.1080/01904167.2019.1584214).

Authors: In the text of the manuscript, a large number of references are used in relation to the effect of zinc sulfate application on safflower. Certainly, it is not possible to include all published articles in this field in one article.

 

Materials and Methods:

Line 107: Authors: The word "but" was deleted.

Line 119: Authors: "was implied" deleted.

Lines 121-123: Authors: The number of days after planting and days after irrigation interruption to harvest was added to the text.

Lines 123-126: the respected reviewer asked " Why did authors choose these zinc concentrations? Was it based in the literature? Please, specify."

Authors: It is informed that these values are based on the author's previous experiences, which were conducted for preliminary experiments with BSc students. In these experiments, we had determined the upper and lower values, and then this experiment was carried out for two postgraduate students (MSc degree) in two years. It should be noted that this information has not been published.

"How leaf sprays were applied? Hand sprays? What was the volume/flow rate applied?"

Authors: The requested information was entered into the text in the lines 133-4.

Also, how many days after sowing was it?

Authors: Days after planting for first and second year for rosette foliar spraying was added to the text in the line 130-1.

How many days after sowing?

Authors: days after planting for first and second year for flowering foliar spraying was added to the text in the line 133.

Line 140: The respected referee has stated that "ml" will become 'mL". Although ml and mL are both correct and both are written in scientific papers and books, the authors made this change.

Line 142: Authors: "four" changed to "4".

Line 145: Authors: "meter" changed to "m".

Line 146: The respected referee has stated that "was" change to "were".

Authors: In response, it is stated that this change is grammatically wrong and this change was not made.

Lines 156-157: Authors: the extra lines were removed.

Table 1 and 2 were wrongly placed in the file.

Authors: The mistakes observed in the PDF text of the article that was sent to the reviewers are probably during the initial conversion of the manuscript to the journal article format, and it was not a mistake on the part of the authors.

Table 1: Please, express the units as dS m^-1 and mg kg^-1

Authors: All the units in the table 1 were changed and modified.

Line 242: Authors: "gram" changed to "g".

- Results:

The respected reviewer stated: "As authors used different factors, the correct would be to use a two-way ANOVA instead of one-way. This way, lowercase letters would compare treatments (control, SA, SR… etc), while capital letters would compare normal with stress. Moreover, the two years must be analyzed separately, not comparing one to another. If you really want to compare 2016 with 2017, you can consider year as another factor (trifactorial) and use another symbol could be used to indicate significant differences (for example # or *). In this context, a table with the summary of ANOVA must be provided as supplementary material".

Authors: It is stated that, the design used was the split block (or strip plot) design based on the randomized complete blocks design (two-way and not one-way). In this design, in addition to the ease of implementation, treatment levels (control, SA, SR… etc.) are placed at the closest distance from each other and their comparison is done more accurately. Also, the comparison of normal with stress conditions is done with the corresponding error.

To study the effect of year, and more importantly, the interaction effect of treatment by year, it is necessary to perform a combined analysis of variance. In this statistical analysis model, compared to multifactorial analysis, in addition to the fact that experimental error is significantly reduced, this reduced error is also divided into two parts, one for testing the effect of year and the other for the testing of the effects of treatments and their interaction with year. This makes the comparison of treatments to be done with much higher accuracy.

Figures 1 with 2; and 3 with 4 must be placed together.

Authors: Due to the large number of treatments in the experiment, in practice it is not possible to merge the figures into each other. If this request is made, the figures will be confused and incomprehensible.

Fig. 3: Please correct kg/ha to kg ha^-1

Authors: It is corrected.

- Discussion:

In general, discussion is well written.

Authors: Thanks

Lines 561-562: Please, provide a citation for these sentences.

Authors: The references of sentences are [9,13,25].

- Conclusions:

-Please, do not use acronyms in the conclusion.

Authors: All acronyms have been changed to original words.

-Include two short sentences in the end of conclusion: the first stating which method and dose were the best option; and the second stating the importance of this finding.

Authors: Regarding the best method used, this article is clearly written in the lines781-4 that the foliar spray method was much more effective than the soil application method. A sentence was added to the end of these sentences regarding the concentration and time of application of zinc sulfate.

Regarding the importance of the findings of this research, a sentence was added to the end of the paragraph.

Reviewer 2 Report

Comments and Suggestions for Authors

Please see the attachment.

Comments for author File: Comments.zip

Comments on the Quality of English Language

Please further summarize and summarize the research purpose of this paper. It is suggested to list the research indicators according to their classification and aspects. Subsequent discussions and conclusions can be written according to different aspects, which may be more clear

Author Response

REVIEWER 2:

This study examined the effects of zinc sulfate applied using different methods on the seed yield and quality of safflower (Carthamus tinctorius L.) under late-stage drought stress, this topic has significant practical meaning, I hope the following comments can help improve further.

1. The abstract is a bit wordy, it is recommended to revise shortly although the journal does not limit the number of For example, lime 33-35, “Under regular irrigation, higher concentrations of zinc sulfate had a greater effect on plant’s performance, but under stress conditions, medium and lower concentrations of zinc showed a greater effect”, we can revise it as “Under regular irrigation, higher concentrations of zinc sulfate enhanced plant performance, but under stress conditions, medium and lower concentrations were more effective” or “Under regular irrigation, higher concentrations of zinc sulfate enhanced plant performance, but under stress conditions, the trend was the opposite.

Authors: Based on this suggestion, the sentence was changed as suggested.

2. Line 31-32, grammatical mistake, usually, in English, "although" and "but" should not be used together in the same sentence, both of them serve to indicate contrast or a turn of thought, having similar functions.

Authors: The word "but" was removed from the text.

3. Line 55, “Also, due to its deep roots, it can extract moisture from the depth of the soil” what does this mean? Does it mean “consume moisture from deep soil”? Besides, why we use these words here? Usually, it is not a wise choice to use deep soil water from perspective of water saving.

Authors: In response to the question of the respected reviewer, it is stated: firstly, it is the introduction of the characteristics of this plant, which is considered as a deep-rooted plant, and secondly, in areas with drought at the end of the season, this trait is an important trait to combat against drought. Because surface root plants will not be able to use the water stored in the lower layers and will die in a short time. The existence of this trait is very necessary for the strategy of irrigation interruption or in rainfed cropping systems in areas with end seasons drought.

4. Please briefly state the basis for choosing the soil application of 20, 40, and 60 kg･ha-1 and spray dose of 2.5, 5, and 7.5 g･L-1 in rosette stage as well as 2.5, 5 and 7.5 g･L-1 in flowering stage. As there are comparison between soil application and leaf application in this study, so is there any relation between the application rate? Otherwise, it may not be meaningful to compare the application ways in the case of different application amounts.

Authors: It is informed that these values are based on the author's previous experiences, which were conducted for preliminary experiments with BSc students. In these experiments, we had determined the upper and lower values and concentrations, and then this experiment was carried out for two postgraduate students (MSc degree) in two years. It should be noted that this information has not been published.

Authors: Regarding why soil and foliar spray concentrations are not equal, and whether there is a relationship between the values, it is stated: In the spray method, the application of high concentrations causes phytotoxicity. Basically, the application amount of foliar spraying chemical compounds is very different compared to the soil method. For example, in our experiment, in the foliar spray method with a concentration of 2.5 g L^-1, only about 375 g ha^-1 of zinc sulfate was used.

There is a data error in line 122, the “5.7” should be “7.5”.

Authors: It is corrected. Thanks to the accuracy of the respected reviewer.

5. Please describe in detail the specific operation time and frequency of the leave

Authors: It was added to the text in the lines 134-5.

6. Please use the same unit form in the manuscript, for example 2.5, 5 and 7.5 g･L-1 in main body, while g/kg in Table. Besides, in Table 1, please clarify the soil line in 2016 and 2017, if there are too many soil information, you can put the same item in the general introduction, for example the soil texture and soil depth.

Authors: Basically, the way to present the concentration of a chemical compound in water is different from the concentration of a compound in soil. When a chemical compound is dissolved in water, it is expressed as g/L, and the concentration of the compound or element in soil is expressed as g or mg/kg of soil.

Writing the soil texture and the depth of field sampling is the conventional method used in presenting the soil characteristics table, and according to the authors, there is no mistake in this field.

7. As there are many treatments in this study, I would recommend giving out a table to list all the treatments and their description together. It would be clearer for the readers to understand. Also, please give out how many treatments or plots together? Are there any replicates about each treatment.

Authors: The description of treatments is written in lines 119 to 126 and it seems that there is no need to insert an additional table in the text. The number of treatments according to the main and secondary factors is 20. Regarding the last question, as written in the line 117, there were three replications in the experiment.

8. Line 137, please also give out the specific size of each plot.

Authors: The size of each plot was added to the text in lines 142-3.

9. Line 143-144. “In the first year, seeding was done on April 1, 2016, and in the second year, on April 5, 2017”, please give out both the seeding data and harvest data to show the growing period.

Authors: These data were added to the text.

10. Please describe in detail the specific irrigation schedule, how about the irrigation way, drip irrigation? How did the end-season drought stress carry out?

Authors: The irrigation method and irrigation intervals are written inside the text, and in the materials and methods section in the lines 149-151. The time of irrigation interruption is explained in line 133. After flowerimg, opening the capitol and appirance of petals, irrigation was stopped in the related treatments and irrigation was not done until the end of the growth period.

11. The structure of the second part could be improved slightly, usually it can be divided to Materials, Experiment design, Measurement and Statistical Analysis, I mean you can put all measurement together in part 3.

Authors: The numbers of all measurements were removed and given in one number.

12. In Table 3, would you give out the meaning of the lower-case letters that represent significance as a note below the Table. It seems like the treatments of both 2016 and 2017 were compared together, if this is the case, I would recommend changing the presentation of the table, or we can use figures to show some of the

Authors: Comparison of averages has been done after two-year combined analysis of variance. Significant letters are used to compare averages obtained in two consecutive years with Duncan's test. Due to the fact that there are many measured traits, it is not possible to present all of traits in the figures form. For this reason, four traits that were important according to the authors are presented in the form of figures and the rest are presented in the table.

13. From the results of various indicators, the indicators of 2017 are lower than those of 2016, why? Please add a simple discussion about the difference. According to the meteorological data of two years, the temperature of 2017 is bit higher than that of 2016, then whether there is a difference in the phenological phase of afflower in 2016 and 2017?

Authors: The reason for the lower values obtained for all the measured traits is written elsewhere in the manuscript, which could be due to the warmer weather and reduced rainfall in the second year. These things caused the plants to grow and developed in drier and hotter conditions than in the first year. For example, despite the fact that in the second year, the planting date was four days late, but the harvest was done about eight days earlier (lines 156-8).

14. Is there any replicates for each treatments, I think yes as there are error bars in figures, while please add error bars for the data in Tables.

Authors: As written in the materials and methods section, the experiment was done with three replications in both years (line 117).

In the comparisons of means by Duncan's method, LSR is calculated using the standard error of the respective means and is the basis of the comparisons, therefore, the results are shown by inserting small letters next to the means. In this type of comparison, it is not necessary and not common to insert the error standard.

15. Why choose drought stress at end-season stage? What is the critical period of water demand for afflower?

Authors: Due to the fact that during recent decades, the intensive harvesting and extraction of underground water in Iran has caused a decrease in the level of underground water. On the other hand, from late spring and summer, most of this restricted water reaches the consumption and irrigation of more valuable crops. As a result, crops with lower economic value usually receive less water. On the other hand, the meteorological data show that in recent years, droughts at the end of the spring and summer show a higher frequency. Therefore, this research was conducted in order to reduce the risk of water shortage at the safflower end growth season by using zinc sulfate.

According to references and our previous researches, the critical stages of safflower for water stress are the emergence and establishment of seedlings, and flowering and pollination stages.

Bijanzadeh, E., Moosavi, Bahador, F. 2022. Quantifying water stress of safflower (Carthamus tinctorius L.) cultivars by crop water stress index under different irrigation regimes. 8. https://doi.org/10.1016/j.heliyon.2022.e09010

Daniel, C., Santos, R., Pinto, J., Hubner, V., Pazuch, F. 2024. Effect of water deficit on safflower cultivation at different phenological stages. Engenharia Agrícola, Jaboticabal, v.44, e20230067. http://dx.doi.org/10.1590/1809-4430

Ponakala, P., Garg, K., Anantha, K. 2024. Water use and yield response of rainfed safflower (Carthamus tinctorius L.) in Vertisols with varying soil depths. Agronomy Journal. 116:1933–1951. 10.1002/agj2.21581

 

16. The discussion section doesn't look concise enough too, for example in line 730-731, this statement has very weak relation with this study, from the view point of pH and EC of the tested soil, it is not calcareous soil, and this manuscript does not set any factors about salinity stress in this study, in my opinion, it is not necessary to show this Please focused on the main topic and revise the discussion part.

Authors: Thanks for the careful opinion of the honorable reviewer. It is stated that the soil of Zanjan University’s Research Station is non-saline; and because of this, there was no problem of salt stress. Regarding the calcareous nature of the soil, according to the amount of calcium in the soil analysis, it is determined as a calcareous soil. The mistake made by the authors in setting up Table 1 was that the pH values were not entered correctly, which was corrected. Thanks again for your attention.

17. There are many research indicators in this study, and some analytical methods such as analytic hierarchy process, cluster analysis or structural equation can be used to further clarify the effects mechanism of soil application or leaf spray of zinc sulfate on the growth and yield of afflower.

Authors: The reviewer's opinion is correct, but since the number of treatments and traits examined is large enough, these statistical methods will probably be used in another article to determine the effect of zinc sulfate application both under non-stress and drought stress at the end of the season conditions on the safflower yield and its components.

18. Line 109-111, please further summarize the research purpose of this paper. It is suggested to list the purposes according to classification of research Subsequent discussions and conclusions can be written according to different aspects based on research purposes, which may be clearer.

Authors: In lines 110-112, the sentences were shortened as much as possible.

Reviewer 3 Report

Comments and Suggestions for Authors

Please find an attached file.

Comments for author File: Comments.pdf

Author Response

REVIEWER#3

The manuscript, titled "Different applications methods of zinc sulphate increased safflower seed yield and quality under end-season drought stress" offers valuable insights into the significant impact of zinc sulfate application on safflower growth and yield under varying irrigation conditions. It reveals that both soil and foliar applications of zinc sulfate enhance plant performance, with foliar spraying proving more effective in increasing seed yield, while soil application boosts biological yield. Notably, zinc sulfate mitigates the adverse effects of drought stress, though the optimal concentration varies with irrigation conditions.

There are several points to be addressed by the authors.

The year of conducting the experiment and soil analysis is stated differently in the manuscript - it is not clear whether the experiment was conducted in 2015-2016 or 2016-2017. I suggest that they be uniform throughout the text (Material and method main text and table 2….)

Authors: Thanks to the accuracy of the honorable referee, the mistake written in the text of the article, in the line 117 was corrected.

Reviewer 4 Report

Comments and Suggestions for Authors

Dear Editors and Authors,

 

I read with interest the manuscript entitled “Different application methods of zinc sulphate increased safflower seed yield and quality under end-season drought stress”. In this study, the effects of four different phosphorus application levels based on a one-factor variable method on phosphorus accumulation and use efficiency and crop yield and quality in the phosphorus-tolerant and sensitive varieties ‘B376’ and ‘B27,’ respectively, of foxtail millet using field pot experiments were investigated. Therefore, the manuscript needs some adjustments so that it can then be forwarded to the publication process. The manuscript has the potential for publication in the journal Horticulturae and needs the following adjustments:

 

TITLE

 

- Delete the term “different”. The title is broad and this word does not add to or change the meaning of the title.

 

ABSTRACT

 

- The objective described should be similar to the excerpt presented in the last paragraph of the Introduction.

 

- What was evaluated? This was not described. Add information about the variables analyzed.

 

- Describe the results in more detail, presenting data with percentages.

- Add the scientific name of the species (Carthamus tinctorius L.) in the keywords.

 

INTRODUCTION

 

- Separate the information about the crop into a new paragraph.

- In the first paragraph, it was mentioned that safflower is flexible to various adverse conditions, such as drought and salinity. Where did you get this information from? Cite the reference.

- In line 75, “Zafari and colleagues” is mentioned. This is incorrect; the correct form would be Zafari et al. (year)...

- Insert hypotheses before mentioning the objectives.

- The objectives should be similar to those presented in the Abstract.

 

MATERIAL AND METHODS

 

- Would subdivided blocks be the same as subdivided plots?

- What was the municipality, state, and country where the study was developed? Only the name of the institution was mentioned.

- In subtopic 2.1, the term “study area” should be added. There is information describing the study site.

- Separate the paragraph on experimental design and treatments. This will help to better understand the information about the research.

- How was this “regular irrigation” done? What was the flow rate used? What irrigation method? How was the amount of water made available to the plants throughout the day quantified? This information is essential, since the safflower crop is sensitive to above 65% of field capacity, depending on the cultivar chosen. Insert this information.

- Add the amount of N present in urea, P in triple phosphate and K in potassium sulfate. Ex. urea (XX% N).

- Table 1 is not formatted correctly. I suggest inserting a figure with the climate data mentioned in Table 1. A single graph could be made with both crops.

- Check the formatting of Table 2. The Table is inserted within the legend.

- In Table 2, what does EC mean? The meaning should be added in the footnote of the Table.

- How many leaves per plant were used to determine the chlorophyll content?

- Was the total leaf area per plant determined?

- How was the LAI calculated? Was any methodology followed? Cite it.

- Was the relative water content determined using the entire leaves? Was this done based on what methodology? Leaf discs are generally used.

- The weight of 1000 seeds was determined according to what methodology?

- In subtopic 2.6 the abbreviation should be removed from the title and added to the text below. Review. Do the same in topic 3.10 (Results).

- What normality test was used? This should be mentioned here.

- Cite the SAS reference.

- The program used for the statistical analyses should be mentioned in the last sentence of the paragraph. Reorganize.

 

RESULTS

 

- Organize according to the sequence of analyses mentioned in the Material and Methods section. The results began by describing the chlorophyll content. This needs to be reviewed.

- Would it be possible to make figures instead of Table 3? Data expressed in Figures is better visualized, especially when several treatments are tested.

- Organize Figure 1. The x-axis (normal and stress) needs to be formatted. The term “stress” is in the lower-left corner of the graph.

- The figures did not compare the harvests (2016 and 2017) and conditions (normal and stress). The dose could be isolated and compared between harvests. Several new analyses and comparisons could be added to improve the results. I suggest that, if possible, this be done.

- Remove the border from all the figures.

-

 

DISCUSSION

 

- Some sections need references.

- Check the description of the results repeatedly. Review all the results described here.

Author Response

REVIEWER#4

Dear Editors and Authors,

 

I read with interest the manuscript entitled “Different application methods of zinc sulphate increased safflower seed yield and quality under end-season drought stress”. In this study, the effects of four different phosphorus application levels based on a one-factor variable method on phosphorus accumulation and use efficiency and crop yield and quality in the phosphorus-tolerant and sensitive varieties ‘B376’ and ‘B27,’ respectively, of foxtail millet using field pot experiments were investigated. Therefore, the manuscript needs some adjustments so that it can then be forwarded to the publication process. The manuscript has the potential for publication in the journal Horticulturae and needs the following adjustments:

 

TITLE

- Delete the term “different”. The title is broad and this word does not add to or change the meaning of the title.

Authors: The term "different" was removed from the title of the article.

 

ABSTRACT

- The objective described should be similar to the excerpt presented in the last paragraph of the Introduction.

- What was evaluated? This was not described. Add information about the variables analyzed.

- Describe the results in more detail, presenting data with percentages.

Authors: From the authors' point of view, it is possible to add requested items to the abstract section. But the problem is in the amount of the abstract, that adding newer content will definitely increase the amount of the abstract. On the other hand, referees such as honorable "referee 2" have requested to reduce the number of abstract words. Regarding the mentioned cases, with all due respect, unfortunately, it was not possible to add sentences to the abstract text.

- Add the scientific name of the species (Carthamus tinctorius L.) in the keywords.

Authors: The scientific name was added to the key words.

 

INTRODUCTION

- Separate the information about the crop into a new paragraph.

Authors: An introduction to oilseed crops and information of safflower was made in a new paragraph.

- In the first paragraph, it was mentioned that safflower is flexible to various adverse conditions, such as drought and salinity. Where did you get this information from? Cite the reference.

Authors: These sentences are mentioned in the [4,5] references.

- In line 75, “Zafari and colleagues” is mentioned. This is incorrect; the correct form would be Zafari et al. (year)...

Authors: It was done.

- Insert hypotheses before mentioning the objectives.

- The objectives should be similar to those presented in the Abstract.

Authors: It seems that the way of presenting the hypotheses and objectives is based on the format of the other articles written and written properly.

 

MATERIAL AND METHODS

- Would subdivided blocks be the same as subdivided plots?

Authors: No, the experimental design used was split-block (or strip plot), which is different from split-plot. In this design, each complete block (replication) is divided in two perpendicular directions into the number of levels of two factors. In other words, each complete block is divided horizontally into the number of levels of one factor and vertically into the number of levels of another factor, and the levels of the factors are randomly placed in these horizontal and vertical strips.

- What was the municipality, state, and country where the study was developed? Only the name of the institution was mentioned.

Authors: The name of city and country was added to the text (line 119).

- In subtopic 2.1, the term “study area” should be added. There is information describing the study site.

Authors: The requested information was entered in section 2.2 (lines 142-3).

- Separate the paragraph on experimental design and treatments. This will help to better understand the information about the research.

Authors: It was done.

- How was this “regular irrigation” done? What was the flow rate used? What irrigation method? How was the amount of water made available to the plants throughout the day quantified? This information is essential, since the safflower crop is sensitive to above 65% of field capacity, depending on the cultivar chosen. Insert this information.

Authors: Most of the questions asked are available in the text of the manuscript. Regular irrigation was done weekly or every 7 days. Irrigation was carried out with plastic types, or brigade types, along the planting rows (see lines 149-150). This method is the conventional irrigation method used by farmers and the authors did the irrigation based on this. It is necessary to inform the respected referee that the safflower plant is sensitive to dumping off diseases and therefore the crown of the plant should be prevented from touching the water. For this reason, this plant is planted on the ridge not in the furrow. It is easy to irrigate safflower and there is no need to calculate 65% field capacity.

- Add the amount of N present in urea, P in triple phosphate and K in potassium sulfate. Ex. urea (XX% N).

Authors: The requested information was added to the text of the manuscript (line 152).

- Table 1 is not formatted correctly. I suggest inserting a figure with the climate data mentioned in Table 1. A single graph could be made with both crops.

Authors: It seems that the esteemed reviewer confused Table 1 and Table 2. Table 1 is the physicochemical characteristics of the field soil and Table 2 is the meteorological data of the two years of the experiment at the research station of Zanjan University. It is not wrong to present meteorological data in tabular form. It can also provide other information that the figure cannot show. For example, the amounts of precipitations or minimum and maximum temperatures can be seen in detail.

"A single graph could be made with both crops." Which both crops? The request of the honorable reviewer was not understood.

- Check the formatting of Table 2. The Table is inserted within the legend.

Authors: It was done.

- In Table 2, what does EC mean? The meaning should be added in the footnote of the Table.

Authors: EC means, Electrical conductivity. Soil electrical conductivity (EC) measures the ability of soil water to carry electrical current. Electrical conductivity is an electrolytic process that takes place principally through water-filled pores. Cations (Ca²⁺, Mg²⁺, K⁺, Na⁺, and NH⁴⁺) and anions (SO₄^2-, Cl^-, NO^3-, and HCO^3-) from salts dissolved in soil water carry electrical charges and conduct the electrical current. Consequently, the concentration of ions determines the EC of soils. In agriculture, EC has been used principally as a measure of soil salinity (table 1); however, in non-saline soils, EC can be an estimate of other soil properties, such as soil moisture and soil depth. EC is expressed in deci Siemens per meter (dS/m).

- How many leaves per plant were used to determine the chlorophyll content?

Authors: The number of leaves which measured for CCI was added to the text (line 206).

- Was the total leaf area per plant determined?

- How was the LAI calculated? Was any methodology followed? Cite it.

Authors: For the two questions raised above, it should be stated: the answers to the questions in lines 206-211 are written carefully and clearly. 8 plants were cut from the ground, their leaves were separated from the plant, and the leaves area were obtained after scanning with a leaf area meter device. After summing up the leaf area of all 8 plants, it was divided into the ground area where the plants were harvested. The obtained number is a unitless parameter because it is the division of the area by the area. A reference was added to the text (line 211).

- Was the relative water content determined using the entire leaves? Was this done based on what methodology? Leaf discs are generally used.

Authors: The reference of methodology is mentioned at the end of the paragraph. The respected reviewer can refer to the reference. A leaf disk is usually used to measure RWC. In this experiment, despite the fact that the safflower leaves at the end of the plant and near the capitol are small in size, an area of about one cm² was cut and measurements were made with a leaf disk.

- The weight of 1000 seeds was determined according to what methodology?

Authors: Based on seed test manuals.

- In subtopic 2.6 the abbreviation should be removed from the title and added to the text below. Review. Do the same in topic 3.10 (Results).

Authors: Writing abbreviations in the title and subtitle is not wrong and is a common practice in writing scientific articles.

- What normality test was used? This should be mentioned here.

Authors: Bartlett's test of Homogeneity of Variances was used, which is added in the text.

- Cite the SAS reference.

Authors: It is added to the text.

- The program used for the statistical analyses should be mentioned in the last sentence of the paragraph. Reorganize.

Authors: Based on the authors' experience and opinion, this comment is not mandatory.

RESULTS

 

- Organize according to the sequence of analyses mentioned in the Material and Methods section. The results began by describing the chlorophyll content. This needs to be reviewed.

Authors: The order of presentation of traits in the results section is almost the same as the order given in the materials and methods section. The beginning of the expression of the results is with the chlorophyll content index.

- Would it be possible to make figures instead of Table 3? Data expressed in Figures is better visualized, especially when several treatments are tested.

Authors: It is certain that all the traits in the table are converted into figures. But this will increase the number of pages of the manuscript. If the journal's editorial board has no problem with this and accepts the proposal, the authors can convert the entire table into the figures.

- Organize Figure 1. The x-axis (normal and stress) needs to be formatted. The term “stress” is in the lower-left corner of the graph.

Authors: It was done.

- The figures did not compare the harvests (2016 and 2017) and conditions (normal and stress). The dose could be isolated and compared between harvests. Several new analyses and comparisons could be added to improve the results. I suggest that, if possible, this be done.

Authors: The figures in the article are the conventional way to show the information obtained from the experiment. Of course, there are other ways to present information, but the authors have used the present method.

- Remove the border from all the figures.

Authors: It was done.

 

DISCUSSION

- Some sections need references.

Authors: All sections checked for references.

- Check the description of the results repeatedly. Review all the results described here.

Authors: It was done.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

1.        1. “Basically, the way to present the concentration of a chemical compound in water is different from the concentration of a compound in soil. When a chemical compound is dissolved in water, it is expressed as g/L, and the concentration of the compound or element in soil is expressed as g or mg/kg of soil.” I think you did not get what I mean, please use the same unit form in the manuscript, I means please use g･L^-1 and g･kg^-1 or g/L and g/kg, not the g･L^-1 and g/kg.

 

2.         2. It is not clear in Table 1, please clarify the two lines of the soil in this table. As the table title “Physico-chemical characteristics of soil of the Agricultural Research Station of the University of Zanjan “, so are they the same soil? Why you listed them in two lines？Besides, if there are many soil information, you can put the same item in the general introduction, for example the “the tested soil is classified to clay loam……”

 

3.         3. “For example, despite the fact that in the second year, the planting date was four days late, but the harvest was done about eight days earlier”. So, does this affect the results of the experiment? As I noticed that the results from 2016 and 2017 were compared together, and I think this is also a factor that caused the difference.

 

4.         4. Please add SE for the data in Tables.

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Reviewer#2

 

1. “Basically, the way to present the concentration of a chemical compound in water is different from the concentration of a compound in soil. When a chemical compound is dissolved in water, it is expressed as g/L, and the concentration of the compound or element in soil is expressed as g or mg/kg of soil.” I think you did not get what I mean, please use the same unit form in the manuscript, I means please use g･L^-1and g･kg^-1 or g/L and g/kg, not the g･L^-1 and g/kg. 

 

AUTHORS:

In all the text, figures and tables, the units were uniform.

 

2. It is not clear in Table 1, please clarify the two lines of the soil in this table. As the table title “Physico-chemical characteristics of soil of the Agricultural Research Station of the University of Zanjan “, so are they the same soil? Why you listed them in two lines？Besides, if there are many soil information, you can put the same item in the general introduction, for example the “the tested soil is classified to clay loam……”

 

AUTHORS:

As you know, in experiments that are replicated in several years, the place of the experiment must not be under cultivation of the same crop in the previous year. This recommendation is because the successive cultivation of a plant in one area causes the development of pests and diseases specific to the same plant. Therefore, in the following year, the presence of pests, diseases or weeds specific to a plant will cause large and inaccurate changes in the results. On the other hand, there is a very strong possibility that a crop planted in a piece of farm will shattering some of its seeds at the time of harvest. As a result, if the same plant is cultivated in the same plot, while this non-observance can cause genetic mixing, it can cause the remaining seeds from the previous year to be mixed with the seeds planted in the new year. As a result, the planting density will be different from the predicted density.

According to the above-mentioned cases, planting was done in a different part of the Research Station of the University each year.

 

3. “For example, despite the fact that in the second year, the planting date was four days late, but the harvest was done about eight days earlier”.So, does this affect the results of the experiment? As I noticed that the results from 2016 and 2017 were compared together, and I think this is also a factor that caused the difference.

 

AUTHORS:

As you know, in multi-year experiments, the goal is to find out the true effect of the treatment by separating the effect of the year, and treatment × year interaction from its effect. With the explanation that a year may be hot, cool, dry or wet. As a result, the year, and treatment × year interaction can have significant effects on the experiment results. In this regard, in the combined analysis of data for several years, if the effect of year and consequently treatment × year interaction is significant or not, the method of comparing means will also be different. In the present experiment, since these two effects were significant, the authors compared the averages as seen in the text of the manuscript.

 

 

4. Please add SE for the data in Tables.

 

AUTHORS:

As it was announced in the first response to the respected reviewers' comments, the means comparison by Duncan's method is calculated by standared erorr, therefore, in this method of presenting the mean comparison, it is not very common to put a standard error.

However, based on the opinion of the respected referee, this item was added to the mean comparison table for all the evaluated traits.

Reviewer 4 Report

Comments and Suggestions for Authors

The changes have been made. The article has potential to be published.

Author Response

Thank you for your important suggestions, now the manuscript is greatly improved.

Round 3

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors,

The the manuscript was basically modified  according to the comments during the first and second rounds. While at last but not least, I noticed that the data of year 2016 and 2017 were still compared together. Usually, two year’s data is considered to be a replication of the previous year. Therefore, I would recommend comparing them separately to highlight the differences between treatments.

Best,

Juan

Author Response

To editor and esteemed reviewer 2:

We appreciate the time and effort that you and the reviewer 2 dedicated to providing feedback on our manuscript. Our special thanks to the academic editor and reviewer 2 whose comments were all insightful and constructive towards improvement of the manuscript. We have incorporated the comment and issues raised by the reviewer 2.

 

REVIEWER#2

 

The the manuscript was basically modified  according to the comments during the first and second rounds. While at last but not least, I noticed that the data of year 2016 and 2017 were still compared together. Usually, two year’s data is considered to be a replication of the previous year. Therefore, I would recommend comparing them separately to highlight the differences between treatments.

 

AUTHORS:

Thanks

 In Table 3 and all figures, the statistical analysis was performed again for the measured attributes; And after comparing the averages, the standard error was calculated and changed in the table 3 and all figures.

Author Response File: Author Response.pdf