Physiological and Biochemical Mechanisms of Exogenously Applied Selenium for Alleviating Destructive Impacts Induced by Salinity Stress in Bread Wheat

Round 1

Reviewer 1 Report

1. 16-17 at different concentration
2. 16-17 specify the modality of administration
3. 18-19 and l. 25-27 present the same concept. I think you can eliminate l. 18-19
4. 28 physio-biochemical traits
5. 31 add the classificator to the scientific name

l.42 I suggest to add a more recent citations ( https://doi.org/10.3389/fpls.2020.603576 and https://doi.org/10.1007/s13562-019-00521-3 )

10. 51 see and possibly cite (https://doi.org/10.3390/agronomy7010018 and https://doi.org/10.3389/fpls.2019.00867)
11. 58 see also and possibly cite https://doi.org/10.3389/fpls.2018.01191
12. 59 see also and possibily cite more recent articles (https://doi.org/10.1016/j.scienta.2020.109866, https://doi.org/10.1016/j.inpa.2017.09.003, https://doi.org/10.1007/s12011-009-8402-1)

Try to highlight the novelty of your study and the differences with similar articles already published

1. 75 how many seeds for each pot?
2. 85 you can eliminate in addition
3. 85 specify the Se form
4. 90 did you modify the soil pH in all thesis?
5. 92-94 did you have also other time point for physiological and biochemical analysis? It would be useful in order to understand the time of action of Se and salt stress and in general in order to monitor the status of the plants
6. 97-136 specify for each parameter how many plants for each thesis?

I think that also a determination of total Selenium in leaves could be useful

Figure 1 and 2 the differences among Se treatments are very small. Are you sure that they are statistically different?

1. 144-152 try to present the results in more detail by analyzing the different parameters

Tables add the SE

Tables 3 and 4 there are formatting errors

1. 247-253 I suggest to remove this part from discussion since it contains concepts already presented in Introduction and Results section

l.329-330 at high levels of salinity the role of proline is quite controversial, explore this further

In general, I suggest to resume the discussion and just compare your results with available literature avoiding parts that are for the introduction section. Better highlight the correlation between the different parameters studied.

Author Response

Dear Editor,

Enclosed please find the revised version of our manuscript entitled “Physiological and biochemical mechanisms of exogenously applied selenium to alleviate devastating impacts induced by salinity stress in bread wheat” (Manuscript ID: agronomy-1203696). With this letter, we would like to thank you and the reviewers for providing constructive suggestions that gave us the opportunity to improve the quality of the manuscript. After carefully reading all comments provided, a major revision of the manuscript is carried out to fulfill the required suggestions.

Yours sincerely,

Authors

Responses to Reviewers Comments

Reviewer 1:

Re: We would like to thank the Reviewer for his time dedicated to our manuscript.

Comments and Suggestions for Authors

16-17 at different concentration

Re: “in” has been replaced by “at” (line 17)

18-19 and 25-27 present the same concept. I think you can eliminate 18-19

Re: The sentence has been deleted (line 19-20)

28 physio-biochemical traits

Re: “attributes” has been replaced by “traits” (line 28)

31 add the classificator to the scientific name

Re: The the classificator has been added (line 30)

42 I suggest to add a more recent citations ( https://doi.org/10.3389/fpls.2020.603576 and https://doi.org/10.1007/s13562-019-00521-3 )

Re: The suggested references have been added (line 44)

51 see and possibly cite (https://doi.org/10.3390/agronomy7010018 and https://doi.org/10.3389/fpls.2019.00867)

Re: The suggested references have been added (lines 53, 54)

58 see also and possibly cite https://doi.org/10.3389/fpls.2018.01191

Re: The suggested reference has been added (lines 61)

59 see also and possibily cite more recent articles (https://doi.org/10.1016/j.scienta.2020.109866, https://doi.org/10.1016/j.inpa.2017.09.003, https://doi.org/10.1007/s12011-009-8402-1)

Try to highlight the novelty of your study and the differences with similar articles already published

Re: The suggested references have been added (lines 62-67) and the paragraph has been rephrased to highlight the novelty of our study.

75 how many seeds for each pot?

Re: Ten seeds were sown in each pot and at full emergence, only seven seedlings were kept (line 78-80)

85 you can eliminate in addition

Re: has been deleted (line 91)

85 specify the Se form

Re: The for has been added (line 91)

90 did you modify the soil pH in all thesis?

Re: Yes, soil pH was modified in all treatments

92-94 did you have also other time point for physiological and biochemical analysis? It would be useful in order to understand the time of action of Se and salt stress and in general in order to monitor the status of the plants

Re: The physiological and biochemical analyses have been performed once at 65 days from sowing for all treatments

97-136 specify for each parameter how many plants for each thesis?

Re: The number of plants have been identified (line 97-104)

Figure 1 and 2 the differences among Se treatments are very small. Are you sure that they are statistically different?

Re: The data have been re-analyzed and the letters on the top of colums have been revised 

144-152 try to present the results in more detail by analyzing the different parameters

Tables add the SE

Re: The results have been presented in more details (lines 152-162),  SE values have been added to all tables

Tables 3 and 4 there are formatting errors

Re: The tables have been re-formatted

247-253 I suggest removing this part from discussion since it contains concepts already presented in the Introduction and Results section

Re: The paragraph has been deleted (283-290)

329-330 at high levels of salinity the role of proline is quite controversial, explore this further

Re: The sentence has been rephrased and more explanations have been added (lines 384-388)

In general, I suggest to resume the discussion and just compare your results with available literature avoiding parts that are for the introduction section. Better highlight the correlation between the different parameters studied.

Re: The discussion has been revised and similar parts to the introduction have been deleted

Reviewer 2 Report

Please explain/describe the followings.

Line 39 omit ‘in’ in ‘decreasing in grain yield.’

Lines 43-44         rewrite the sentence

Line 49                 use a different word instead of ‘drought’

Lines 49 – 50      rewrite the sentence

Line 55                 remove ‘plants’ after microorganisms.

Line 82                 spell out all numbers if they are under ten.

Line 86                 remove ‘with’ in dripping with’

Lines 93 – 94      What are ‘physio-biochemical attributes’?  Ten plants for each measurement were used?

Line 95                 use ‘plant height’ instead of ‘plant high’, use leaf area instead of ‘leaves area.’

Line 94                 define what ‘physiological maturity’ means

Line 94                 Ten plants for each treatment or for all measurements?

Lines 98 – 99      rewrite the sentence.

Lines 133 & 208               Why was Se content not measured?

Lines 277 – 279 There are two groups of crops depending on Se accumulation capacity: the high and low accumulator.  Onions can accumulate at a high concentration of Se.

Lines 333 – 335 Reference is required

Why was SeCl2 used?  Selenium nitrate or nitrite, instead?

Why sprayed, not drenched?

There are two Figure 3s.

Why were Se concentrations (2, 4 and 8 uM) used?

How many total plants for each measurement? Pn was determined in two hours for all leaves?  How many IRGA were used?

Author Response

Dear Editor,

Enclosed please find the revised version of our manuscript entitled “Physiological and biochemical mechanisms of exogenously applied selenium to alleviate devastating impacts induced by salinity stress in bread wheat” (Manuscript ID: agronomy-1203696). With this letter, we would like to thank you and the reviewers for providing constructive suggestions that gave us the opportunity to improve the quality of the manuscript. After carefully reading all comments provided, a major revision of the manuscript is carried out to fulfill the required suggestions.

Yours sincerely,

Authors

Responses to Reviewers Comments

Reviewer 2:

Re: We would like to thank the reviewer for his time dedicated to our manuscript.

Please explain/describe the followings.

Line 39 omit ‘in’ in ‘decreasing in grain yield.’

Re: “in” has been deleted (line 38)

Lines 43-44  rewrite the sentence

Re: The sentence has been rephrased (line 44-47)

Line 49   use a different word instead of ‘drought’

Re: “physiological drought” has been replaced by “water deficiency” (line 49)

Lines 49 – 50  rewrite the sentence

Re: The sentence has been rephrased (line 50-51)

Line 55  remove ‘plants’ after microorganisms.

Re: “plants” has been deleted (line 56)

Line 82  spell out all numbers if they are under ten.

Re: The numbers less than ten have been written in letter  (83, 88)

Line 86    remove ‘with’ in dripping with’

Re: “with” has been deleted (line 92)

Lines 93 – 94 What are ‘physio-biochemical attributes’? 

Re: “physio-biochemical attributes” has been replaced by “physio-biochemical parameters” (line 100)  

Line 95  use ‘plant height’ instead of ‘plant high’, use leaf area instead of ‘leaves area’

Re: “high” has been replaced by “height” and “leaves” has been replaced by “leaf” (line 99)

Line 94  define what ‘physiological maturity’ means

Re: “physiological maturity” has been defined “when the spikes had ripened and turned to yellow” (line 100-101)

Line 94  Ten plants for each treatment or for all measurements?

Re: Ten plants from each treatment were used for measuring all agronomic traits

Lines 98 – 99 rewrite the sentence.

Re: The sentences have been rephrased (line 104-107)

Lines 277 – 279 There are two groups of crops depending on Se accumulation capacity: the high and low accumulator.  Onions can accumulate at a high concentration of Se.

Re: This sentence is reporting the results of Hawrylak-Nowak (2008) in maize as a cereal crop (331-333)

Lines 333 – 335 Reference is required

Re: Reference has been added (line 393)

Why was SeCl₂ used?  Selenium nitrate or nitrite, instead?

Re: The chemical compound of selenium dichloride was available

Why sprayed, not drenched?

Re: Previous reports documented that Se foliar spray is effective in enhancing plant physioligcal process (Hu et al., 2002. J. Sci. Food Agric.82, 869–872; Nawaz et al., 2015. Ecotoxicol. Environ. Saf. 113, 191-200; Zhu et al., 2017. Sci. Hortic.  218, 87-94), accordingly it was used as foliar spray.

There are two Figure 3s.

Re: Sorry for this fault,  the schematic diagram has been converted to be Figure 4

Why were Se concentrations (2, 4 and 8 μM) used?

Re: The used concentration was selected according to a preliminary study

How many total plants for each measurement? Pn was determined in two hours for all leaves?  How many IRGA were used?

Re: Ten plants from each treatment were used for measuring all physiologicsal parameters (line 98).  Pn was determined using two devices over two consecutive days.

Reviewer 3 Report

The current study was aimed to evaluate the Se-mediated mechanisms to mitigate the adverse effect of salinity in wheat plants. Interestingly, the authors use three different Se levels and found that 8 μM SeCl2 showed the most protective effect than other doses. It would have been nice trying with different cultivars. However, this is a nice manuscript, and there are no major issues with the experimentations. Still, there is a scope of revision. Some of the comments are as follows:

• Line 42, define abbreviations such as H2O2, O2-, and OH-.
• Line 73, how the healthy seeds were selected? How was it done? What was the particular reason for choosing only one cultivar, i.e., Misr-1?
• Line 75, please explain how many pots were used? How many plants were grown per pot? How many pots/plants were used for each replication?
• Line 86, please explain how much (approximately) Se was sprayed per plant/pot?
• Line 106, shift the formula to the next line and define in the next line. Do not merge it within the text.
• Line 138, mention the developer name and location for SPSS.
• I strongly suggest presenting the results either % increase/decrease or fold change for significant results. Please check all the results sections and address this suggestion. Also, tell us if they are significant or not?
• The discussion has been well described and presented with good scientific logic. I like the idea of adding a mechanistic mechanism in Fig 3.

Author Response

Dear Editor,

Enclosed please find the revised version of our manuscript entitled “Physiological and biochemical mechanisms of exogenously applied selenium to alleviate devastating impacts induced by salinity stress in bread wheat” (Manuscript ID: agronomy-1203696). With this letter, we would like to thank you and the reviewers for providing constructive suggestions that gave us the opportunity to improve the quality of the manuscript. After carefully reading all comments provided, a major revision of the manuscript is carried out to fulfill the required suggestions.

Yours sincerely,

Authors

Responses to Reviewers Comments

Reviewer 3:

The current study was aimed to evaluate the Se-mediated mechanisms to mitigate the adverse effect of salinity in wheat plants. Interestingly, the authors use three different Se levels and found that 8 μM SeCl₂ showed the most protective effect than other doses. It would have been nice trying with different cultivars. However, this is a nice manuscript, and there are no major issues with the experimentations. Still, there is a scope of revision. Some of the comments are as follows:

Re: We would like to thank the Reviewer for his time dedicated to our manuscript and presenting positive aspects in our manuscript. We highly appreciate the constructive criticisms which improved the manuscript.

Line 42, define abbreviations such as H2O2, O2-, and OH-.

Re: Definitions have been added (lines 41-42)

Line 73, how the healthy seeds were selected? How was it done? What was the particular reason for choosing only one cultivar, i.e., Misr-1?

Re: Healthy seeds were selected carefully with good quality and free from insect infestations. Misr-1 is a high-yielding commercial cultivar is recommended by the Egyptian Ministry of Agriculture and Land Reclamation.

 Line 75, please explain how many pots were used? How many plants were grown per pot? How many pots/plants were used for each replication?

Re: . Ten seeds were sown in each pot and at full emergence only seven seedlings were kept in each pot. Ten pots were used in each treatment, more details have been added (lines 78-90).

Line 106, shift the formula to the next line and define in the next line. Do not merge it within the text.

Re: The formula has been shifted into the next line (line 114)

I strongly suggest presenting the results either % increase/decrease or fold change for significant results. Please check all the results sections and address this suggestion. Also, tell us if they are significant or not?

Re: The result section has been revised and percent of increase or decrease has been added

The discussion has been well described and presented with good scientific logic. I like the idea of adding a mechanistic mechanism in Fig 3.

Re: Thanks so much for your support

Round 2

Reviewer 1 Report

The manuscript was improved and now I think it is suitable for publication

Author Response

We thank the Reviewer for his time dedicated to our manuscript

Reviewer 3 Report

The authors have addressed my comments, and the MS has been improved. I have no more major comments; however, a minor comment must be resolved before acceptance.

• Please add this information in the methodology section (Healthy seeds were selected carefully with good quality and free from insect infestations. Misr-1 is a high-yielding commercial cultivar is recommended by the Egyptian Ministry of Agriculture and Land Reclamation).

Author Response

We would thank the Reviewer for his time dedicated to our manuscript. The suggested addition has been done (line 73-76).