Elevated Atmospheric CO₂ Concentration Influences the Rooting Habits of Winter-Wheat (Triticum aestivum L.) Varieties

Round 1

Reviewer 1 Report

At the outset, I would like to express my warm appreciation to the authors for such an amazing and time-demanding manuscript (MS) titled 'Elevated Atmospheric CO₂ Concentration Influences the Rooting Habits of Winter Wheat (Triticum aestivum L.) Varieties. The quality of the manuscript was up to the mark and organized concisely in a harmonic manner. The visual presentation and data interpretation was sounds ok and the objectives were correctly addressed in the results and findings. The writing sequences and English were commendable.  However, In addition to that, I would like to add a few improvements and specific clarifications for the quality enrichment of the MS. 

Firstly, as Elevated Atmospheric CO₂ is mostly associated with stomatal regulation thus impacting photosynthesis, it would be better to correlate the findings through a few photosynthetic attributes like transpiration rate, gaseous exchange, leaf florescence, stomatal conductance and chlorophyll pigmentation. I would better suggest the authors to insert these parameters if possible by now. However, there are some minor but important mentions to work on with, which are mentioned below.

[line no. 95] what type of inorganic NPK sources were used for balanced plant nutrition?

[line no. 96] continuous line sowing or proper spacing were maintained?

[line no. 109-110] please indicate in the picture, the name of the specific part of the setup. 

[line no. 125] please specify the duration of the water stress period. how many days does it take for water content to drop below 8-10%?

[line no. 125] Why the stressed plants were rewatered after this certain duration of stress period? 

[line no. 140] specify exact days it required 

Comments for author File: Comments.pdf

Author Response

Responses to Reviewer 1:

 

First of all, we would like the thank you for taking the time to revise our manuscript and define comments based on that we can improve the quality of the manuscript further.

 

At the outset, I would like to express my warm appreciation to the authors for such an amazing and time-demanding manuscript (MS) titled 'Elevated Atmospheric CO2 Concentration Influences the Rooting Habits of Winter Wheat (Triticum aestivum L.) Varieties. The quality of the manuscript was up to the mark and organized concisely in a harmonic manner. The visual presentation and data interpretation was sounds ok and the objectives were correctly addressed in the results and findings. The writing sequences and English were commendable.  However, In addition to that, I would like to add a few improvements and specific clarifications for the quality enrichment of the MS.

 

Firstly, as Elevated Atmospheric CO2 is mostly associated with stomatal regulation thus impacting photosynthesis, it would be better to correlate the findings through a few photosynthetic attributes like transpiration rate, gaseous exchange, leaf florescence, stomatal conductance and chlorophyll pigmentation. I would better suggest the authors to insert these parameters if possible, by now. However, there are some minor but important mentions to work on with, which are mentioned below.

These parameters were not measured in this trial, but we are very thankful for these comments, and we will be taken into consideration these aspects of the CO₂ enrichment by planning our experiments in the future.

[line no. 95] what type of inorganic NPK sources were used for balanced plant nutrition?

The manuscript was completed and the fertilization approach was specified.

[line no. 96] continuous line sowing or proper spacing were maintained?

The number of plants per row had been indicated.

[line no. 109-110] please indicate in the picture, the name of the specific part of the setup.

 

[line no. 125] please specify the duration of the water stress period. how many days does it take for water content to drop below 8-10%?

The manuscript is completed with this information.

 

[line no. 125] Why the stressed plants were rewatered after this certain duration of stress period?

It was simulated how the precipitation after a long dry period influences the plant’s behaviour.

[line no. 140] specify exact days it required.

Done

Author Response File: Author Response.pdf

Reviewer 2 Report

In paragraph 2.3 on the analysis of the obtained results, the authors mention the names of the tests that they used to compile the statistical results. You mention the ANOVA test, which, after reviewing the entire manuscript, was not mentioned. Please, specify this information.

Please, specify the description of figure 1 (line 114). I mean specifically adding information regarding the first and second parts of the figure. It would be nice to name these photos A and B respectively and describe what they represent.

Please format Table 1 (line 133) in accordance with the editorial requirements, also that all tables in the manuscript have the same formatting. I appreciate the detailing of the codes in this work, it significantly improves the readability of the work.

Table 3/4/5 please expand the abbreviation n.r. in the description below each table.

Line 241, please change the name of the table to table 4 and not 3. Additionally, please add the top line to the table (above 400 and 750 ppm).

The data presented in all 3 figures (Figure 4/5/6) are hardly legible. It seems to me that moving the legend from the right side of the chart to the top will increase the area of the chart. In addition, I am asking you to change the place of the added values of 30, 60 and 90 cm in such a way that they do not overlap with the bars visible on the chart. You should also sign what the horizontal axis shows. The full and incomplete colors of the bars used by the authors are very confusing and difficult to read. Is it possible to mark in a different way the static significance presented in the charts? I appreciate the use of a consistent scale of values in all three figures.

After the Conclusion section, there should be information about additional materials added by the authors, which should also be described in accordance with the journal's guidelines:

“Supplementary Materials: The following supporting information can be downloaded at: www.mdpi.com/xxx/s1, Figure S1: title; Table S1: title; Video S1: title. "

Please, complete these data and give names to individual tables from the Supplementary Materials file. Additionally, please quote the tables included in the Supplementary Materials in the main text.

Author Response

Responses to Reviewer 2:

First of all, we would like the thank you for taking the time to revise our manuscript and define comments based on that we can improve the quality of the manuscript further.

 

In paragraph 2.3 on the analysis of the obtained results, the authors mention the names of the tests that they used to compile the statistical results. You mention the ANOVA test, which, after reviewing the entire manuscript, was not mentioned. Please, specify this information.

The results of the ANOVA had been highlighted in the text of the Results as well.

Please, specify the description of figure 1 (line 114). I mean specifically adding information regarding the first and second parts of the figure. It would be nice to name these photos A and B respectively and describe what they represent.

Done.

Please format Table 1 (line 133) in accordance with the editorial requirements, also that all tables in the manuscript have the same formatting. I appreciate the detailing of the codes in this work, it significantly improves the readability of the work.

Done

Table 3/4/5 please expand the abbreviation n.r. in the description below each table.

Done

Line 241, please change the name of the table to table 4 and not 3. Additionally, please add the top line to the table (above 400 and 750 ppm).

Done

The data presented in all 3 figures (Figure 4/5/6) are hardly legible. It seems to me that moving the legend from the right side of the chart to the top will increase the area of the chart. In addition, I am asking you to change the place of the added values of 30, 60 and 90 cm in such a way that they do not overlap with the bars visible on the chart. You should also sign what the horizontal axis shows. The full and incomplete colors of the bars used by the authors are very confusing and difficult to read. Is it possible to mark in a different way the static significance presented in the charts? I appreciate the use of a consistent scale of values in all three figures.

The place of the legends and the structure of the graphs had been revised.

After the Conclusion section, there should be information about additional materials added by the authors, which should also be described in accordance with the journal's guidelines:

 

“Supplementary Materials: The following supporting information can be downloaded at: www.mdpi.com/xxx/s1, Figure S1: title; Table S1: title; Video S1: title. "

 

Please, complete these data and give names to individual tables from the Supplementary Materials file. Additionally, please quote the tables included in the Supplementary Materials in the main text.

 

Done

Author Response File: Author Response.pdf

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

The objective looks very general I think you can write down some specific objectives.
The narrative of the M&M is incomplete, please include the statistical experimental design, treatment arrangement Factorial 2x2x3: 2 CO2 levels, 2 watering levels, and 3 genotypes. 
Biomass (BM), grain yield (GY), thousand kernel weight (TKW), and harvest index 150 (HI) analysis looks incomplete; did you include the interactions in the analysis? For Tukey or HSD test is better to write down the letters along whit the means.
Root length data analysis is poor, in my opinion, you have double repeated measurements, soil deep and growth stage along with the factors CO2, watering, and genotype.
You measured also soil temperature and soil water content, did these variables can affect the root length? If the case, you should include these variables as a covariate. 
Is there any correlation between root length and weight of the total aboveground biomass, grain weight, and thousand kernel weight?
There is no statistical analysis for root length, you analyzed certain percentages inadequately. You have a factorial experiment plus repeated measurements in time (growth stages) and in space (soil deep), then you must analyze the data using the appropriate model.
Graphs are interesting but the quality is not good. 

Reviewer 2 Report

Review: Elevated Atmospheric CO2 Concentration Influence the Rooting Habits of Winter Wheat (Triticum aestivum L.) Varieties

Interesting topic of work:

Congratulations on taking up a very interesting topic of work, concerning the influence of drought on the yield of winter wheat. There is an extremely important issue related to the worldwide increase in the intensity and frequency of extreme droughts. Despite the interesting research topic, the presented work still requires many changes. Below I am enclosing a list of questions to which I am asking for your response:

1. In section 2.1 the authors mention that two types of preparations were used during the research: "Fungicide Thiovit Jet (Syngenta AG, Basel, Switzerland) active ingredient: sulfur) and Insecticide Karate 2.5 WG (Syngenta AG, Basel, Switzerland) (active ingredient : lambda-cyhalothrin) was used twice against powdery mildew and aphids. " In what doses were both preparations given? At what time intervals were these preparations applied? Additionally, at what phytophenological stages were these preparations applied? Did the use of a combination of the two preparations have any visible effect on the plant?
2. In section 2.1 in line 114-115 you mention that the containers have been divided into two equally sized parts (optimally hydrated and exposed to drought) thanks to the use of water insulating plastic. What water-insulating material was used in this experiment?
3. In section 2.3. for the analysis of the obtained results, please provide the p value for which the results were considered statistically significant, as this information is missing here. In addition, you mention the use of multi-way ANOVA for analyzes, but the tables in this publication do not include the results of the analyzes presented.
4. In table 1, are the values of BM (g), GY (g), TKW (g), HI (%) presented as mean values obtained from all replicates performed? What are the SD values for this data?
5. Are the results obtained in Table 1 for the individual parameters BM (g), GY (g), TKW (g), HI (%) depending on the genotype of the plants tested and factors NC, EC, C, D statistically significant? Please indicate which results are relevant to each other?
6. Please explain the abbreviation n.s. under table 1.
7. In section 3.2 you present data based on the division of results into categories marked with abbreviations: BBCH17, BBCH21, BBCH29, BBCH37, BBCH51, BBCH69, BBCH77 and BBCH83, please explain the abbreviations used in the work, preferably in section 2.2, where in line 130 -131 you are mentioning it for the first time. Please write a sentence about it, which is why such phytophenological stages of wheat have been included. Please consider whether attaching a simplified diagram of these individual phases would help to illustrate the stages at which the research was carried out.
8. In the first sentence of section 3.2 (line 184-186) reference is made to Figure 3, followed by Table 2, which is discussed later in the text. It is followed by Table 3, and only then the cited Figure 3. This means that when reading and analyzing data, one has to look for the answers of figures or tables in completely different places on the page, the ordering of materials attached in the form of tables or figures closer to the text in question will significantly improve the reader tracking the results.
9. Table 2. Please shorten the number of decimal places of the attached data to 3 items (currently the values written in the format of 6 decimal places do not bring significant values to the work, but are only difficult to track).
10. Table 3. Please explain what the yellow values mean in the table.
11. Figure 3. In the caption under the figure, please explain what the individual graphs marked with letters A-F present.
12. Additionally, in the attached form, figure 3 is hardly legible. He proposes some changes to increase its transparency. Create two panels of charts: one for testing at 400ppm and the other for testing at 700ppm. Use a larger font for the names of these panels. Then, since the same legend is used in all charts, I propose to place one on the top of each panel (under the name of the panel), which will allow you to stretch the charts and better present the data contained therein. For a better understanding of the colors used in the graphs, I suggest choosing one color corresponding to the data for parameter C and use a color gradient for individual C30, C60 and C90 (e.g. from light to dark blue) and the same for parameter D. This will emphasize the differences within the examined parameter. Please pay attention to the position of the side scales, so that they are equal everywhere.
13. Table 4. Please shorten the number of decimal places of the attached data to 3 items (currently the values written in the format of 6 decimal places do not contribute significant values to the work, but are only difficult to track).
14. Table 6. Please shorten the number of decimal places of the attached data to 3 items (currently the values written in the format of 6 decimal places do not bring significant values to the work, but are only difficult to track).
15. Figure 4 Please indicate on the photos the scale in which the photos were taken and align the letters with those in Figure 3 (printed letters in the upper left corner).
16. Table 7. Please explain what the yellow values mean in the table.
17. Please place the tables closer to the place where they are cited, which will facilitate the tracking of the results you describe (table 4).
18. After the end of the experiment, were the root mass of the tested cultivars determined? If so, please attach such data, if not, please comment why it was not carried out, since in Table 1 you present the results for the mass of the aerial parts.
19. In my opinion, it would be useful to prepare a summary table presenting the results for all three varieties together, something similar to tables 3, 5, 7 ("Effects of elevated CO2 concentration on the root length development of three type of Winter wheat in various phenophases, in three soil layers, under normal and limited watering ”) but using only the mean values ​​and compare their statistical significance between the different parameters and varieties tested. It will provide answers on which variety does best and which is worst in drought conditions. Such a table can be placed at the end of the result section and the obtained results can be discussed in the text or used in the discussion section. Where in line 308-309 mention you: In our experiment, Mv Karizma showed the most intense responses to the increased CO2 level. "