Assessment of Nitrogen Use Efficiency in Algerian Saharan Maize Populations for Tolerance under Drought and No-Nitrogen Stresses

Round 1

Reviewer 1 Report

Dear authors, I appreciate your well written paper on "Assessment of nitrogen use efficiency in Algerian Saharan maize populations for tolerance under drought and no-nitrogen stresses". The objective of the current study is to assess tolerance and genetic effects of Algerian populations under no-nitrogen and water stress.  The paper is well organized, the topic of research is good. it's an important work, and the manuscript has been well prepared. I highly recommended to publish this manuscript in “Agronomy”, after minor revision.

Minor comments

• The authors should improve the introduction part, most sections have sentences strung together arbitrarily without a clear structure, and transition between sentences in the introduction is confusing.

For example:

• In the introduction section, please try to add some information regarding the climate changes and water requirement for the maize globally, please see and cite the following references: https://www.mdpi.com/2225-1154/7/10/124
• What about the molecular regulation response of maize under the climate changes (abiotic stresses), the authors can read and cite the following recent references as I see it can help the authors to improve their hypothesis:

https://doi.org/10.3389/fpls.2016.01978 ; https://pubmed.ncbi.nlm.nih.gov/32799616/

https://www.tandfonline.com/doi/full/10.1080/15592324.2020.1807722

• The experimental design is appropriate, but please add in a factorial experiment and the levels of the factors.
• In the results section, the authors should add a state of art and need one sentence at the end of each paragraph to show to readers what happen in the whole paragraph
• The discussion part is well interrupted and well presented

Please accept this paper shall the authors address the minor revision

Author Response

Thank you very much for your valuable corrections. We have made our best to improve the manuscript accordingly. Here follows our responses:

Q1. The authors should improve the introduction part, most sections have sentences strung together arbitrarily without a clear structure, and transition between sentences in the introduction is confusing. In the introduction section, please try to add some information regarding the climate changes and water requirement for the maize globally, please see and cite the following references.

R: We have added the recommended information and reference. The structure was also revised.

Q2. The experimental design is appropriate, but please add in a factorial experiment and the levels of the factors.

R: We have included the information about the experimental design in this paragraph:

“Treatments were arranged in a split-split-plot design with two main plots representing the water regimes (water stress and well-watered as control), two subplots that include the two nitrogen treatments 0 kg/ha and 120 kg/ha of nitrogen. Finally, the genotypes were randomized within each subplot, in experimental units consisting of one 6-m row with 0.7 m row spacing. Three repetitions were used for each trial.“

Q3. In the results section, the authors should add a state of art and need one sentence at the end of each paragraph to show to readers what happen in the whole paragraph

R: We have added a summary sentence at the end of each paragraph or group of paragraphs; however, according to the publication rules, the state of the art has to be in Introduction.

Reviewer 2 Report

The presented manuscript and the research presented in it address a combination of two stress factors - water deficit and nitrogen nutrition. This is a current problem in many countries around the world. For this reason, it is a topic that has good potential for citation. The abstract is fine. Literary review focusing on the issue and used current literary sources. The goals were clearly stated. The methodology is written slightly. Was there any total precipitation? What were the other soil characteristics (content of other nutrients in the soil, pH)? The results are based on the data in the tables. Unfortunately, I did not find the table in the manuscript, even when checking the manuscript repeatedly. However, there are references to them in the text. Please add or explain. The presented manuscript and the research presented in it address a combination of two stress factors - water deficit and nitrogen nutrition. This is a current problem in many countries around the world. For this reason, it is a topic that has good potential for citation. The abstract is fine. Literary review focusing on the issue and used current literary sources. The goals were clearly stated. The methodology is written slightly. Was there any total precipitation? What were the other soil characteristics (content of other nutrients in the soil, pH)? The results are based on the data in the tables. Unfortunately, I did not find the table in the manuscript, even when checking the manuscript repeatedly. However, there are references to them in the text. Please add or explain. The discussion is rather descriptive. It is not clear from the summary whether the research objectives have been met. It is necessary to check the bibliography and its citations. The discussion is rather descriptive. It is not clear from the summary whether the research objectives have been met. It is necessary to check the bibliography and its citations.

Author Response

Thank you very much for your valuable corrections and contributions and sorry for missing the tables. We have made our best to improve the manuscript accordingly. Here follows our responses:

Q1. The methodology is written slightly. Was there any total precipitation? What were the other soil characteristics (content of other nutrients in the soil, pH)?

R: Temperatures and precipitations of the experimental field in 2018-2019 were added as a table and some other soil characteristics.

Q2. The results are based on the data in the tables. Unfortunately, I did not find the table in the manuscript, even when checking the manuscript repeatedly. However, there are references to them in the text. Please add or explain.

R: Sorry, we have missed them when including the original text in the template by error. We added all the ten tables.

Q3. It is not clear from the summary whether the research objectives have been met. It is necessary to check the bibliography and its citations.

R: We have modified the discussion accordingly and checked the bibliography again.

Round 2

Reviewer 2 Report

The authors modified and supplemented the submitted manuscript according to the requirements that resulted from the revision of the original manuscript. Comments and remarks were accepted. Missing result tables have been added to the text. I have a comment on the above processing of results. The tables show statistically significant differences, but I recommend adding standard deviations. The methodology has been supplemented. The discussion was supplemented and its quality was improved. The used literary sources are adequate and adequate.

Author Response

Thank you for the recommendation; however, given the large size of the tables and the amount of numbers included in them, if we add the standard deviations to all the means, we will duplicate the amount of numbers and the size of the tables, and they would be too large for the size of the template of Agronomy.

Indeed, we could split the tables, but them we’ll have four more tables, and we already have ten tables. Moreover, the tables have the LSD and the letters for mean comparisons. Furthermore, as we include the tables of the analyses of variance, if anyone wants to compare the means by using a method different from the Fisher’s protected LSD that we have used, he can do so by obtaining the necessary information from the analyses of variance