Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes

Round 1

Reviewer 1 Report (New Reviewer)

The manuscript explains the effects of exogenously application of Polyamines on different agronomic traits of Sesame under different drought stresses. The manuscript title “Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes” has scientific worth but it requires significant modification and necessary clarification especially in the methods section .

Reviewer Comments:

1-      In abstract; Line 23-34: the authors explained about the effects of mild and serve drought stress on the sesame plant. We all know that drought stress decreases the photosynthetic pigments, gas exchange, water relations, and plant nutrient content (N, P, and K) in plants. Also we know that drought stress enhances the oxidative stress markers (malondialdehyde, electrolyte leakage, superoxide, and hydrogen peroxide), osmoprotectants (free proline, soluble sugars, α-Tocopherol, ascorbate, and glutathione), and antioxidant enzyme activities in plants and so on… These all results were already published in different plants, and there is no new scientific information. I suggest authors to delete the line 23-34 from abstract. From title it reflects that the authors will explain the effect of different polyamines application on the drought stressed sesame plants. As the authors used three different polyamines foliar spray so I suggest authors to focus on the polyamine results as I explained in comment 2.

2-      I suggest authors to add the effect of different polyamines (Spd, Put, and Spm) result on different parameters in the abstract.

3-      In the methods section, 2.4 and 2.5 the authors didn’t explained any detail of instruments, protocols, and reagents and chemical used for determining different assays. Just writing it was done before is not enough, instruments, chemicals and the procedure steps also influence the results. Sometimes the protocol varies from crop to crop and the type of samples. The 2.4 and 2.5 need brief explanation.

4-      Modify the 2.5 title as “Determination of Antioxidant Enzymatic Activities”. Also the protocol details are necessary for 2.5.

5-      Line 163: “absorbances recorded at 340 nm” on which spectrophotometer???? Company, manufacturer, etc,.

Author Response

Dear Editor,

We would like to thank you and the reviewers for the time and efforts devoted to our manuscript entitled “Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes” (agronomy-2231950). We have revised the manuscript according to the comments and suggestions pointed out by the reviewers. We have addressed the comments of the reviewers in a point-by-point below in red color; in addition, we have highlighted all the associated changes made to the manuscript using track changes.

Yours sincerely,

Authors

Responses to Reviewers' Comments

Reviewer 1:

The manuscript explains the effects of the exogenously application of Polyamines on different agronomic traits of Sesame under different drought stresses. The manuscript title “Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes” has scientific worth but it requires significant modification and necessary clarification, especially in the methods section.

Re: We would like to thank the Reviewer for his time dedicated to our manuscript and his positive assessment of our work.

Reviewer Comments:

1- In the abstract; Lines 23-34: the authors explained the effects of mild and serve drought stress on the sesame plant. We all know that drought stress decreases photosynthetic pigments, gas exchange, water relations, and plant nutrient content (N, P, and K) in plants. Also, we know that drought stress enhances the oxidative stress markers (malondialdehyde, electrolyte leakage, superoxide, and hydrogen peroxide), osmoprotectants (free proline, soluble sugars, α-Tocopherol, ascorbate, and glutathione), and antioxidant enzyme activities in plants and so on… These all results were already published in different plants, and there is no new scientific information. I suggest authors delete the lines 23-34 from the abstract. The title reflects that the authors will explain the effect of different polyamines applications on drought-stressed sesame plants. As the authors used three different polyamine foliar spray so I suggest authors to focus on the polyamine results as I explained in comment 2.

Re: The line 23-34 have been deleted and more results have been added to the abstract as suggested (please see lines 37-53).

2- I suggest authors to add the effect of different polyamines (Spd, Put, and Spm) result on different parameters in the abstract.

Re: The effect of polyamines (Spd, Put, and Spm) has been added to the abstract as suggested (lines 37-53). 

3- In the methods section, 2.4 and 2.5 the authors didn’t explain any detail about the instruments, protocols, reagents, and chemicals used for determining different assays. Just writing it was done before is not enough, instruments, chemicals and the procedure steps also influence the results. Sometimes the protocol varies from crop to crop and the type of samples. The 2.4 and 2.5 need a brief explanation.

Re: More details have been added to sections 2.4 and 2.5 as suggested (lines 148-211)

4- Modify the 2.5 title as “Determination of Antioxidant Enzymatic Activities”. Also, the protocol details are necessary for 2.5.

Re: The title has been modified and more details have been added as requested (lines 192-212)

5- Line 163: “absorbances recorded at 340 nm” on which spectrophotometer???? Company, manufacturer, etc.

Re: More details have been added (line 211)

Thanks so much for your review that contributed considerably to improve our manuscript.

Reviewer 2 Report (New Reviewer)

The manuscript enitled ’Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes’ is about two-season field trial that assessed the impact of applying polyamines (Spm, Spd, Put) on sesame plants under different levels of drought stress.

Exogenous application of PAs, particularly putrescine, reduced the negative effects of water deficit and improved the plants' physiological, biochemical, anatomical, and agronomic parameters and crop water productivity. The results suggest that exogenous application Put can be used to enhance the yield and water productivity of sesame plants under drought stress.

The method description is proper. They have measured photosynthetic pigments, leaf gas exchange parameters, membrane stability, excised leaf water retention, total nitrogen, total phosphorus, total potassium, MDA, total inorganic ions leaked out, several antioxidant agents and enzyme activities, total soluble sugars, α-Tocopherol, ascorbate level and reduced glutathione in leaves.

The results are properly described. Both tables and figures have nice design and they are informative.

Little bit strange, that they show their results and data mostly in tabular format, than on figures. Nevertheless, this is not problem.

Overall, authors carefully confirmed, that exogenous application of PA substances helps restore balance to nutrient contents, tissue integrity, and photosynthetic efficiency, and increases the levels of osmoprotectants and antioxidants, leading to increased productivity and quality (yield and oil content) of drought-stressed sesame plants compared to untreated plants.

After authors make the following minor mistakes, I recommend this MS to publish in the special issue.

 

Before publish, I have some minor remarks:

-          Please, complete the description of foliar gas exchange analysis with details (open or closed system, actinic light intensity, CO₂ level,

-          Please, write GSH instead of GsH

-          In row 151 corrigate ’Fifty-fife’

-          In row 159, corrigate ’spectro-photo-chemically’ to ’spectro-photo-chemically’

-          In row 179 write as ’kg hectare^-1’ and then remove unnecessary space

-          In row 182 write as ’kg m^-3’

-          I strongly recommend, that check the whole MS for mistypings and grammatic errors, because there may little bit more exist in the text

-          Is PA-priming really eco-friendly way to mitigate drought stress? PAs are generally known as toxic bioactive agents. Is there any information by authors how many time is necessary to loose toxic nature for the applied PAs? If possible, please add some information to study.

-          A kind of vectorgraphic summary figure would improve the quality of paper

Author Response

Dear Editor,

We would like to thank you and the reviewers for the time and efforts devoted to our manuscript entitled “Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes” (agronomy-2231950). We have revised the manuscript according to the comments and suggestions pointed out by the reviewers. We have addressed the comments of the reviewers in a point-by-point below in red color; in addition, we have highlighted all the associated changes made to the manuscript using track changes.

Yours sincerely,

Authors

Responses to Reviewers' Comments

Reviewer 2:

The manuscript entitled ’Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes’ is about two-season field trial that assessed the impact of applying polyamines (Spm, Spd, Put) on sesame plants under different levels of drought stress. Exogenous application of PAs, particularly putrescine, reduced the negative effects of water deficit and improved the plants' physiological, biochemical, anatomical, and agronomic parameters and crop water productivity. The results suggest that exogenous application Put can be used to enhance the yield and water productivity of sesame plants under drought stress. The method description is proper. They have measured photosynthetic pigments, leaf gas exchange parameters, membrane stability, excised leaf water retention, total nitrogen, total phosphorus, total potassium, MDA, total inorganic ions leaked out, several antioxidant agents and enzyme activities, total soluble sugars, α-Tocopherol, ascorbate level and reduced glutathione in leaves. The results are properly described. Both tables and figures have a nice design and they are informative. A little bit strange, that they show their results and data mostly in tabular format than on figures. Nevertheless, this is no problem. Overall, authors carefully confirmed, that exogenous application of PA substances helps restore balance to nutrient contents, tissue integrity, and photosynthetic efficiency, and increases the levels of osmoprotectants and antioxidants, leading to increased productivity and quality (yield and oil content) of drought-stressed sesame plants compared to untreated plants.

After the authors make the following minor mistakes, I recommend this MS to publish in the special issue.

Re: We would like to thank the Reviewer for his time dedicated to our manuscript and his positive assessment of our work.

Before publishing, I have some minor remarks:

- Please, complete the description of gas exchange analysis with details (open or closed system, actinic light intensity, CO₂ level)

Re: More details have been added as suggested (lines 147-153)

- Please, write GSH instead of GsH

Re: Done as suggested throughout the manuscript

- In row 159, corrigate ’spectro photo chemically’ to ’Spectro-photo-chemically’

Re: Done as suggested (line 204)

- In row 179 write as ’kg hectare-1’ and then remove unnecessary space

Re: Modified as suggested (line 227)

- In row 182 write as ’kg m-3’

Re: Modified as requested (line 228)

- I strongly recommend, that check the whole MS for mistypings and grammatic errors, because there may little bit more exist in the text

Re: The manuscript has been carefully revised for mistyping and grammatical errors

- Is PA priming an eco-friendly way to mitigate drought stress? PAs are generally known as toxic bioactive agents. Is there any information by authors on how many time is necessary to lose the toxic nature of the applied PAs? If possible, please add some information to the study.

Re: Polyamines are valuable plant growth regulators for detoxification of reactive oxygen species (ROS), methylglyoxal detoxification, and reinforcement of antioxidative properties under stress conditions as elucidated by Seo et al., 2019 (Frontiers in Plant Science 10, 1331); Alcázar et al., 2020 (Cells 9, 2373) and Nahar et al. 2016 (Frontiers in Plant Science 7:1104). Therefore, exogenously applied polyamines at adequate rates do not exert toxic effects on the treated plants.

- A kind of vectorgraphic summary figure would improve the quality of paper

Re: Schematic diagram explaining the mechanisms of polyamines (Spm, Spd, and Put) in mitigating the adverse effects of drought stress on sesame plants has been added as suggested (Figure 2, line 467-471).

Thanks so much for your review which contributed considerably to improve our manuscript.

Round 2

Reviewer 1 Report (New Reviewer)

The authors did sufficient revisions!

Author Response

Reviewer 1. The authors did sufficient revisions

Re: We would like to thank the Reviewer for his time dedicated to our manuscript and his positive assessment of our revisions.

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

In the manuscript entitled ‘Physiological, Biochemical, Anatomical, and Agronomic Responses of Sesame to Exogenously Applied Polyamines under Different Irrigation Regimes’, the authors showed an interesting experimental set up to go deep on the understanding of how polyamines might be a great to overcome future climate conditions in sesame plants. However, some modifications might significantly improve the manuscript giving a higher impact on the publication. Therefore, I hope the authors will find the questions helpful to improve their manuscript.

 

 

First of all, I was surprised for the highly self-citation ratio along the manuscrit. I’d like the authors to explain the reason of these self-citations giving special attention to the following:

 

Reference 10: Desoky, E.-S.M.; Elrys, A.S.; Mansour, E.; Eid, R.S.M.; Selem, E.; Rady, M.M.; Ali, E.F.;  Mersal, G.A.M.; 474 Semida, W.M. Application of biostimulants promotes growth and productivity by fortifying the antioxidant 475 machinery and suppressing oxidative stress in faba bean under various abiotic stresses.

 is cited in the  following sentence:

‘Inducing the plants to drought stress under field conditions restricts turgor and water content, decreases CO2 uptake and photosynthesis activity, reduces transpiration, and limits gaseous exchange’.

 

References 64, 65 and 66

64. Mansour, E.; Desoky, E.-S.M.; Ali, M.M.A.; Abdul-Hamid, M.I.; Ullah, H.; Attia, A.; Datta, A. Identifying drought-tolerant genotypes of faba bean and their agro-physiological responses to different water regimes in an arid Mediterranean environment.

65. Abd El-Mageed, T.A.; Belal, E.E.; Rady, M.O.A.; Abd El-Mageed, S.A.; Mansour, E.; Awad, M.F.; Semida, W.M. Acidified biochar as a soil amendment to drought stressed (Vicia faba L.) plants: Influences on growth and productivity, nutrient status, and water use efficiency.

66. Desoky, E.-S.M.; Mansour, E.; Ali, M.M.A.; Yasin, M.A.T.; Abdul-Hamid, M.I.E.; Rady, M.M.; Ali, E.F. Exogenously used 24-epibrassinolide promotes drought tolerance in maize hybrids by improving plant and water productivity in an arid environment

all cited in the following sentence:

It devastatingly impacts plant development, growth, and productivity

 

Reference 84: Desoky, E.-S.M.; Mansour, E.; El-Sobky, E.-S.E.A.; Abdul-Hamid, M.I.; Taha, T.F.; Elakkad, H.A.; Arnaout, 646 S.M.A.I.; Eid, R.S.M.; El-Tarabily, K.A.; Yasin, M.A.T. Physio-biochemical and agronomic responses of faba 647 beans to exogenously applied nano-silicon under drought stress conditions  

is cited in the following sentence:

‘Accordingly, these antioxidants protected sesame plants from oxidative damage and have the potential to act as a free radical scavengers’

 

THE ‘MATERIAL AND METHODS’ SECTION is briefly written, and sometimes the methods that were followed must have had some modifications. If the methods were not exactly the same as in the cited bibliography, the authors should precisely describe the modifications.

One example that I’d like the authors to explain is how they quantified MDA.

Did they really follow reference 42 from 1983 (Mukherjee, S.; Choudhuri, M. Implications of water stress-induced changes in the levels of endogenous 558 ascorbic acid and hydrogen peroxide in Vigna seedlings. Physiol. Plant. 1983,) by isolating cloroplasts?

Why did the authors choose this method?

 

IN THE ‘RESULTS’ SECTION:

It was difficult to follow the increases and decreases on so many parameters only with the exposed tables. I suggest to the authors to convert the most important results to a figure (histogram) where the readers will see much faster the impact of the PAs application under drought stress.

 

Moreover, TABLE 6 only presents the results regarding Put.

Why?

The Table description includes the 3 PAs, why?

 

Finally, results are not written to be read. The authors should re-write the results to highlight the strongest impact on water stress and after PAs application. Now it is only a ‘copy-paste’ section that no reader wants to read.

 

DISCUSSION

 

In my opinion the authors should rewrite this section. Particularly, few precision was given and vague expressions such as ‘FAVOURABLE VALUES’ were used. I think that the discussion should be more carefully structured.

 

MINOR REVISION:

 

References in the introduction do not fit with the described sentence. Please explain the reason of citations: 10, 11, 12 and 32.

 

<< 65 >> is Proline an antioxidant? Could you explain why?

 

<< 75 & 76 >>The first time that each word is abbreviated into the manuscript body, must be fully written at the first time:

 

<< FIGURE 1 >> TW or DW?

Maybe the x axis should be described in the figure caption.

 

Reviewer 2 Report

In recent years, researchers have proposed many mitigation measures during drought by exogenous application of hormones, nanoparticles, microelements, osmoprotectants, etc., to the leaves of various crops.

The foliar application of polyamines during drought is not new at all. I cannot agree with the opinion of the authors that only limited information is available on the physiological, biochemical and other properties after the application of polyamines in plants. The mechanisms of action are similar in all types of angiosperms, including sesame.

The experimental research design is simple, the authors used standard methods. Data on the number of repetitions when measuring RWC, ACO2, etc. are missing. It is also important to state the protocol for measuring photosynthesis - length of exposure, light intensity, Rh and the like. The results mainly confirm earlier findings.

Based on the known published results of other authors, a positive effect of polyamines on plant physiology was possible to assume. The authors confirmed the expected effects for sesame plants. Therefore, the innovativeness of the research is not high. The effect of polyamines on the physiological and biochemical properties of plants is poorly understood. The authors only note the differences between the variants without a deeper analysis.

The results are inappropriately processed into tables. It is standard to organize them into graphic models and images. The results must be self-reading and not the reader having to study hundreds of numerical data. The whole manuscript lacks deeper analysis and content organization, and the manuscript seems simple in content quality.

The authors do not cite many relevant publications, so they do not know the current state of the literature. I bring to your attention several interesting, original comprehensive articles: https://doi.org/10.3390/ cells10020261; DOI: 10.1007/s00344-018-9896-6; https://doi.org/10.1016/B978-0-12-818204-8.00021-7; 

https://doi.org/10.1016/j.indcrop.2018.05.064; doi:10.1080/15548627.2020.1847797; https://doi.org/10.3389/fpls.2018.01945; 

Therefore because of the above flaws, I can not endorse the publication of this MS in this esteemed periodical.

My decision is "Reject"

 

Reviewer 3 Report

Dear authors, congrats for conducting the experiences and sharing the results through this paper. I found your manuscript clear and concise, well documented, the methods are properly described and supported by other researchers. 

Regarding the Material and method section, I have some questions: how many plants were used per replication or what surface of land was cultivated as experimental field. 

I suppose that in the tables, are comprised the mean values of all the replications of both years?

On the file attached, you will find some messages where I suggested some modifications. Otherwise, the manuscript includes expected results and the conclusions ae based on it.

The reference section is reach and most of them are recent studies.

 

 

Comments for author File: Comments.pdf