Exogenous ABA Enhances the Antioxidant Defense System of Maize by Regulating the AsA-GSH Cycle under Drought Stress
Round 1
Reviewer 1 Report
This is not what I expected from the title, so the title should be changed. To determine "scavenging", one would need to know the rate of production as well as the current content, to estimate the rate of scavenging. All that was measured was the content. I would suggest that the experimental methods (i.e. water stress) may well have affected the rate of production, which would affect the content without necessarily changing the rate of scavenging.
I was initially totally confused by the wording "post stress" and "after stress"- that is not at all what was meant - what was referred to was the number of days of ongoing stress.
I am concerned that the water stress was defined only by the soil water potential, with no measure of leaf water potential. Surely application of ABA could affect the leaf water potential at the same soil water potential. If the leaf physiology were controlled by leaf water potential rather than by soil water potential, the conclusions could have been quite different. Also, what happens when ABA is applied to "unstressed" or "control" leaves? I guess that I would have expected the responses to be related to measurements of the ABA content of leaves, since I assume the leaves synthesize ABA in response to low water potential in addition to the amount applied.
I do not understand how SWP-100 can measured the irrigation amount, as stated.
Author Response
Thank you for your advises.The response has been completed.
1.The title has been changed.
2.The wording "post stress"and "after stress"has been corrected.
3.The data of relative water content of leaves have been added in the article.
4.Team members found that the effects of exogenous application of ABA and endogenous ABA content on physiological response under stress were different, or even the opposite. The specific mechanism is unclear. My next research direction is to explore the mechanism of exogenous ABA or endogenous ABA regulating plant physiological processes from the perspective of molecular biology.
5. According to the weighing method, record the weight of dry soil and water under different water potential.
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Abstract
“Zhengdan958” – please explain
Figure 1. – In my opinion the figure could be improved – the content is ok, but visualisation is immature.
Methods
“(3) water stress + ABA, i.e., foliar sprayed with ABA (0.5 mmol L-1) under water stress” – water stress? You meant drought stress, probably. The phrase “water stress” is not clear.
Results
Lack of water content is a serious of drawback of this paper. I suggest to recalculate values and showed per DW. Please see the note: (Kovacik J., 2021. Basic physiology and biochemistry in environmental/experimental plant studies: How to quantify and interpret metabolites correctly Environmental Pollution, 286, 117192) and consider the recalculation of results per g DW. In drought-stress investigation the water content in the plants should be monitored. Currently it is difficult to draw reliable conclusions.
The number of repetition should be given in all figure captions.
Discussion
“MDA content can also evaluate the drought tolerance of maize [47].” – it is not clear, please explain this sentence.
Author Response
Thank you for your advises.The response has been completed.
1. Zhengdan958 is the name of maize variety.
2.Figure 1 has been modified.
3.Water stress has been replaced by drought stress.
4.The data of relative water content of leaves have been added in the article.
5.The number of repetition has been given in all figure captions.
6.Discussion has been explained.
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The authors have done a good job of improving this manuscript. I think it is now quite convincing, and requires no further revision.
Author Response
Thank you!
Reviewer 2 Report
Unfortunately, the authors still have not solved the problem water content in the samples. For example, I guess (based on a new figure) that plants at 10 days of treatment contained 92, 83, and 75% of water for control, ABS+stress, and stress, respectively. So after calculation the “true” values of MDA are c.a. 31 nM/g DW, 35 nM/g DW, and 22 nM/g DW for control, ABS+stress, and stress, respectively. Similar to other variables for example AsA content 52 uM/g DW, 25 uM/g DW, 7 uM/ DW for control, ABS+stress, and stress, respectively.
As you see these values (“true values”) are significantly differ form values given per g of FW. Particular investigation of drought stress for plants needs very much such approach. I recommend again to see the paper: (Kovacik J., 2021. Basic physiology and biochemistry in environmental/experimental plant studies: How to quantify and interpret metabolites correctly Environmental Pollution, 286, 117192)
Author Response
Thank you very much for your suggestion and the latest reference. This will be of great significance to my future research. I thought about the trends of metabolite values can be informative in this article (changes in response to applied treatments or environmental factors) before. Now I understand deeply if interspecific comparison and subsequent calculation are carried out in the future, the absolute value must be also accurate enough. In the future in-depth and complex research in this area, I will focus on the problem. This will be a major progress in my future scientific research work. Thank you again for your guidance.
Round 3
Reviewer 2 Report
I am willing to accept the Authors' explanation. So the MS can be published in its current form.
