Exogenous Hemin Confers Cadmium Tolerance by Decreasing Cadmium Accumulation and Modulating Water Status and Matter Accumulation in Maize Seedlings

Round 1

Reviewer 1 Report

This is a well-organized manuscript illustrating the role of Hemin in alleviating the Cadmium toxicity in Maize. The phenotyping data presented in this manuscript are sufficient to address the authors’ conclusions. Even though there is no molecular data illustrating the mechanism, the simple conclusion of the positive role of Hemin seems to be solid. However, there are still some small errors that may need to be addressed by the authors regarding to the acceptance of this manuscript.

1. Since my expertise is not in chemistry, my concern is that whether Hemin reacts with cadmium chloride in the solution? If so, a major issue appears since this may reduce the cadmium concentration for the stress treatment. It might be better if the authors can illustrate/confirm that CdCl2 does not react/combine with Hemin and mention in the materials and methods (part 2.1).
2. Line 66, I get confused with the sentence. What do the authors mean by ‘level of human diet’. Might be better if the authors revise the sentence.
3. Line 67, typo. harms to or Harmful to.
4. Line 130, TF and BCF have full names in line 122, why don’t NPT and PCs in Line 130 and DIMBOA and PAL (Line 140) have full names? Also, does EtOAc need a full name in line 143? I think the authors may need to be consistent with these abbreviations.
5. Line 152, I don’t like the recipe about the solution by describing the PVP input amount as ‘a little’. This seems to be not scientific.
6.  Line 238 and Line 239, ‘cell wall’ means mesophyll cell wall? Or root cell wall? A detailed description might be necessary.

I would suggest this manuscript to be accepted if the above requests can be satisfied, especially for item 1.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The authors of the manuscript entitled "Exogenous Hemin Confers Cadmium Tolerance by Decreasing Cadmium Accumulation and Modulating Water Status and Matter Accumulation in Maize Seedling" presented an interesting work on how Hemin application mitigates cadmium stress in maize plants. The  manuscript has a nice structure and the results have good presentation, yet there are many points that need attention.

1. The abstract needs extensive English editing. Please check English grammar and spelling
2. Throughout the text and especially in Introduction section extensive English editing in grammar and spelling is needed
3. Line 45: It is not clear if this sentence describes a reference or a conclusion of the current work. Changes in presentation should be made. Additionally, throughout the text there are many sentences that are not clear about the content and what they mean, regarding a reference or a conclusion of the current work. Changes in the presentation should be made.
4. Line 63: Italics for Medicago sativa
5. Line 71: change "was" to "is" in Hemin was a feasible
6. Line 94: change "leaves" to "leaf"
7. Explain DIMBOA content in materials and method section
8. Abbreviations should used after the first appearance of the word in the text. For example, line 130: NPT concentration and line 222: Non protein thiol 
9. Section 2.8: Please present the methodology of how the fractionation was achieved. Analytical protocol should be described. Lines 136-137 dot not describe the method of fractionation 
10. Line 159: change "figures" to "tables"
11. Line 297: What the authors mean by "Hemin is the promoter of HO1"?Gene promoters are genomic regulatory regions upstream of the coding region of the gene. The authors should rephrase.  

Author Response

Please see the attachment.

Author Response File: Author Response.docx