Organic Nitrogen Fertilizer Selection Influences Water Use Efficiency in Drip-Irrigated Sweet Corn^†

Round 1

Reviewer 1 Report

Manuscript title: Organic Nitrogen Fertilizer Selection Influences Water Use 2 Efficiency in Drip Irrigated Sweet Corn.

The over- all aim of this study was to assess whether phytohormones, micronutrients, and forms of inorganic N in organic fertilizers affect WUE (fWUE and iWUE) and leaf gas exchange components of drip irrigated sweet corn under typical application methods and field conditions. 

The title and subject of the manuscript are very interesting from the methodological and practical point of view, suitable and adequate. The scientific content contributes to the space in which it develops.

The manuscript is well designed and written, and therefore could be acceptable after minor revision for possible publication in “agriculture”. However, some corrections should be considered as listed below:

Abbreviations needs to be defined at first mention and used consistently thereafter throughout the manuscript.

Keywords should appear in alphabetical order, and do not repeat words in the Keywords that have been previously cited in the Title.

The abstract should illuminate the main findings of the manuscript that can serve as a stand-alone document. However, authors have represented abstract in more generalized form. Authors should emphasize the levels of increment/reduction of different parameters assessed in % age values.

Add latest references in the introduction.

Page 1, Line 34, please add the below reference at the end of sentence:

Fertilizer type has potential to influence WUE (Agathokleous et al., 2022).

Agathokleous, E., Kitao, M., Komatsu, M. et al. Single and combined effects of fertilization, ectomycorrhizal inoculation, and drought on container-grown Japanese larch seedlings. J. For. Res. (2022). https://doi.org/10.1007/s11676-022-01565-3

Please consider a statistical analysis heading at the end of Materials and Methods.

Authors should provide evidence that data/scores obtained with replications.

Discussion is more generalized and it has not been explained in the light of the observed results at many places. Please revise the discussion part for such parameters explaining the mechanism of action.

Please provide a Figure showing the experimental planning and images of plants differently treated.

Please use the below reference in your manuscript:

S.; Yang, H.; Zhang, R.; Li, Y.; Meng, F.; Ma, J. Impact of Drip Irrigation and Nitrogen Fertilization on Soil Microbial Diversity of Spring Maize. Plants 2022, 11, 3206. https:// doi.org/10.3390/plants11233206

Level of English is good however in a few places some syntax errors are present.

Author Response

Abbreviations needs to be defined at first mention and used consistently thereafter throughout the manuscript.--Thank you for this reminder. We have made the necessary corrections.

Keywords should appear in alphabetical order, and do not repeat words in the Keywords that have been previously cited in the Title.--Thank you. We have edited the keywords to meet the criteria.

The abstract should illuminate the main findings of the manuscript that can serve as a stand-alone document. However, authors have represented abstract in more generalized form. Authors should emphasize the levels of increment/reduction of different parameters assessed in % age values.—We have added more detail to the Abstract, specifically in regard to the correlations (lines 21-23).

Add latest references in the introduction.

Page 1, Line 34, please add the below reference at the end of sentence:

Fertilizer type has potential to influence WUE (Agathokleous et al., 2022).

Agathokleous, E., Kitao, M., Komatsu, M. et al. Single and combined effects of fertilization, ectomycorrhizal inoculation, and drought on container-grown Japanese larch seedlings. J. For. Res. (2022). https://doi.org/10.1007/s11676-022-01565-3

We added a citation to this paper in line 87. Since the paper’s focus is on the amount of fertilizer (not the type), we felt it fit better in that section.

Please consider a statistical analysis heading at the end of Materials and Methods.—Since we did not use headings in the Materials and Methods at all, it seems strange to add only one heading. Please advise us if we should add additional headings in the Materials and Methods.

Authors should provide evidence that data/scores obtained with replications.—I don’t understand this comment. There were four replications of every treatment and measurement. Please clarify.

Discussion is more generalized and it has not been explained in the light of the observed results at many places. Please revise the discussion part for such parameters explaining the mechanism of action.—We propose some possible mechanisms of action in the text.

Please provide a Figure showing the experimental planning and images of plants differently treated.—Unfortunately, we did not take photographs of the plants from different treatments.

Please use the below reference in your manuscript: S.; Yang, H.; Zhang, R.; Li, Y.; Meng, F.; Ma, J. Impact of Drip Irrigation and Nitrogen Fertilization on Soil Microbial Diversity of Spring Maize. Plants 2022, 11, 3206. https:// doi.org/10.3390/plants11233206—We have read this paper and did not find it to be relevant to this study, since its focus is on the impact of irrigation and nitrogen levels on soil microbial diversity, which we did not evaluate.

Reviewer 2 Report

 Reviewer comment for paper:”Organic Nitrogen Fertilizer Selection Influences Water Use 2 Efficiency in Drip Irrigated Sweet Corn”

Dear appreciated Authors,

The manuscript “Organic Nitrogen Fertilizer Selection Influences Water Use 2 Efficiency in Drip Irrigated Sweet Corn” was found innovative, interesting, since it represent specific technology for sweet corn in agriculture production and to improve Water use efficiency (WUE).

The manuscript is generally well-written, but there are a few details which should be considered (see below) and some revisions have to be made before it can reach a publishable value. However, to improve the quality of the manuscript, I propose the following:

It is indeed that use of Cyanobacterial bio-fertilizer has the potential to become a new and sustainable source of N fertilizer, which can be produced on farm and has the great potential to fix atmospheric nitrogen supplementing or replacing chemical fertilizers. The author should also point out about the reduction of the harmful effect of abiotic stresses on plants observed by cyanobacteria specially its ability to tolerate salinity, plant germination under drought stress and others.

In the part of Introduction, the authors should point out and side effect of the potential presence of harmful cyanotoxins which has delayed the use of such cyanobacterial biomass, which can be found in large fresh water ecosystems around the world. However, the presence of these cyanotoxins in irrigation water of plants could inhibit their growth. Furthermore, these cyanotoxins could present a threat to human health by indirect exposure through bioaccumulation in the tissues of irrigated plant. The authors should point out this in Introduction.

Furthermore, in Conclusion, beside of positive effect on examined traits it could be better to ad Sentence that beside of positive effect, further research should be done to obtain the realistic assessment between positive and negative, side effects of Cyanobacterial bio-fertilizer.

Abstract:

Abstract is generally well-written and provide shortly general information regarding to the investigation.

 Line 11:

There is a need firstly to write full name and then it is available to put abbreviations, as a:  Nitrogen (N), since it is the first time mentioned, especially in Abstracts

 Line 23:

There is a need firstly to write full name and then it is available to put abbreviations, as a:  salicylic acid (SA), since it is the first time mentioned, especially in Abstracts

Introduction:

Line 29: Firstly to write full name and then put abbreviations, specially when is the first time mentioned

Line 108:  Delete one more space between two sentences.

Based on all, author's paper should be accepted for publication, after minor revisions, because the paper represents a significant contribution for improvement agricultural production.

Best regards,

Dr. Nataša Ljubičić

Comments for author File: Comments.pdf

Author Response

It is indeed that use of Cyanobacterial bio-fertilizer has the potential to become a new and sustainable source of N fertilizer, which can be produced on farm and has the great potential to fix atmospheric nitrogen supplementing or replacing chemical fertilizers. The author should also point out about the reduction of the harmful effect of abiotic stresses on plants observed by cyanobacteria specially its ability to tolerate salinity, plant germination under drought stress and others.—We added a statement and citation about how cyanobacteria can improve a plant’s tolerance of abiotic and biotic stresses to the Introduction (line 55).

In the part of Introduction, the authors should point out and side effect of the potential presence of harmful cyanotoxins which has delayed the use of such cyanobacterial biomass, which can be found in large fresh water ecosystems around the world. However, the presence of these cyanotoxins in irrigation water of plants could inhibit their growth. Furthermore, these cyanotoxins could present a threat to human health by indirect exposure through bioaccumulation in the tissues of irrigated plant. The authors should point out this in Introduction.—Thank you for this suggestion. We added a statement regarding cyanotoxin production and testing to the Conclusions section (lines 380-382).

Furthermore, in Conclusion, beside of positive effect on examined traits it could be better to ad Sentence that beside of positive effect, further research should be done to obtain the realistic assessment between positive and negative, side effects of Cyanobacterial bio-fertilizer.—We added a statement regarding the need for this assessment to the Conclusions section, as requested (lines 384-386).

Abstract:

Abstract is generally well-written and provide shortly general information regarding to the investigation.

Line 11:

There is a need firstly to write full name and then it is available to put abbreviations, as a:  Nitrogen (N), since it is the first time mentioned, especially in Abstracts

Line 23:

There is a need firstly to write full name and then it is available to put abbreviations, as a:  salicylic acid (SA), since it is the first time mentioned, especially in Abstracts

Introduction:

Line 29: Firstly to write full name and then put abbreviations, specially when is the first time mentioned

Line 108:  Delete one more space between two sentences.

Based on all, author's paper should be accepted for publication, after minor revisions, because the paper represents a significant contribution for improvement agricultural production.

Thank you for pointing this errors out. We have corrected them in the revised manuscript.