A ¹⁵N-Tracing Study to Explore the Coupling Effects of Biochar and Nitrogen Fertilizer on Tomato Growth, Yield, Nitrogen Uptake and Utilization, and the Rhizosphere Soil Environment under Root-Divide Alternative Irrigation

Round 1

Reviewer 1 Report

Paper ‘A 15N-tracing study to explore the coupling effects of biochar and nitrogen fertilizer on tomatoes growth,yield,nitrogen up-take and utilization and rhizosphere soil environment’ represent comprehensive research on coupling effects of biochar and nitrogen fertilizer on tomato growth, nitrogen utilization and their soil environment. Additionally, to determine the optimal biochar and nitrogen fertilizer coupling mode for enhanced tomato growth, quality, and soil environment under the alternative partial root-zone irrigation mode the technique for order preference by similarity to ideal solution was applied as a ranking tool. Application of biochar with fertilizers in agriculture production is an actual research topic. Paper is very informative and generally well-written, with some minor corrections to be made, that are listed below. 

As water-saving irrigation method is important issue in this paper (as stated in lines 85-87), I suggest the authors include it in the title.

Line 85-87: Results from this study would provide a theoretical basis for improving the water and nitrogen fertilizer utilization efficiency, fruits yield and quality, and achieving sustainable soil utilization under alternate partial root- zone irrigation.

Line 153: ‘Using the second ear of mature tomatoes to determine quality’ –did you mean ‘year’?

Generally, there are too many tables in the text. I suggest making some of them a supplementary material (e.g. Table 9 and 10)

Author Response

Reply:Title has modified, including water-saving irrigation method (lines 5)

Reply:Closest to the ground, there are five tomatoes growing together(figure), called one ear fruit. As the plant grows, second ear fruit will grow above the first ear fruit.

Compared to the graph, this study table can more clearly express the experimental results, and any missing table will confuse readers.

Author Response File: Author Response.pdf

Reviewer 2 Report

Abstract

Is there any point in using 2021S and 2021A if it is not used further in the Abstract? A space is required after a comma and a period, this applies to the entire text. Otherwise the text is difficult to read.

How to understand the last sentence of the Abstract? Avoid such long sentences and write your idea more clearly.

Keywords: Repeating the same terms in the title and keywords is not necessary. You can choose others from your manuscript – as Latin name of tomatoes etc.

Introduction

Although the English language is generally not bad, sometimes the text is written so vaguely that it is difficult to understand the thought. Too long sentences, when one part of the sentence does not fit with the other, are also disturbing. Language correction, help of a native speaker is required.

For example: Line 30-31, 34-36, 40-44.

Line 59. What is Vc - abbreviations should also be given.

Line 68 – “loam soil had the highest yield”? What does that mean?

It is recommended to make the Introduction as a unifying logical story about the problem. It is currently fragmented with no logical transitions to the next paragraph.

At the end of the Introduction, the authors did not clearly state the main aim of the work, but only gave the tasks to be performed. Therefore, the aim of the research should be more clearly formulated. The use of Pearson correlation analysis could not be the goal; it is only a tool for data analysis.

Materials and Methods

Line 94-95. “The experimental region is a typical temperate continental climate” - What does it mean?

2.2. Experimental materials

Table 1. Abbreviations should also be given in the legends of the Tables and Figures. What is TN? What do you mean with soil-holding capacity?

Line 100. What is Zhongyan 958F1"? Tomato variety?

In general, it is very confusingly written how the tomatoes were planted. Can't understand - first planted, then poured the soil? You need to write down exactly what you did in a simple, clear and coherent way.

2.3. Experimental design

Tomatoes were planted in pots, but the doses of materials are indicated per ha. It is also advisable to indicate how much fertilizer and biochar you used in 1 pot.

Line 129-132. Write more clearly how the N fertilizer was applied.

2.4.1. Plant growth indicators

Line 140. “Plant height and stem diameter were measured every 2 days during tomatoes growth.” What was the purpose of measuring every 2 days, was this data used somewhere?

Line 148. “to kill” Why so bloodthirsty - better – to fix.

Line 150. “Three tomato plants were randomly selected from each treatment and picked at maturity.” Tomato plants were picked or tomato fruits?

Line 153. “Using the second ear of mature tomatoes”. What is second ear.

Results

The main problem - all Tables and Figures should be self-explanatory, without returning to the Methods section. All abbreviations deciphered. In order to evaluate significant differences between the results, the standard errors, the least significant differences, should be indicated.

Currently, the reader's only option is to believe you. This is not correct for a scientific article.

For example, Table 5. What is IWUE, DSL?

Line 217. “The differences of roots, stems, leaves, and fruits between B0N3 and B2N1 were significant (P<0.05)…” It is not clear what is being compared. Figure 1 also does not explain what is being compared with what.

Table 8. Did soil pH really measure in mol/L? It is unbelievable that there can be a significant difference in soil reaction if the differences are 0.02 units: B0N1 – 7.76 c, B11N1 – 7.78 b, B1N3 – 7.74 d. Then it must be very convincing statistically proven.

Discussion

Overall, the Discussion is the clearest and best written section, but it also needs some corrections.

Line 339-340. What is the relationship of the first sentence to the following text?

Line 360-362. “In this study, the nitrogen derived from fertilizer of tomato organs decreased”. What is fertilizer of tomato organs?

Check that you clearly separate the data and conclusions from the literature from what you have found in your research. For example: However, the loss of fertilizer nitrogen gradually increased with the increase of nitrogen application [30].

Conclusions

It is recommended to improve the conclusions. In the conclusions, it is necessary to summarize and generalize the acquired new knowledge. Do not form conclusions so detailed. Outline further research directions, may be you have not yet identified some issues from these experiments. How do your recommendations align with current tomato growing practices? Building conclusions like this will increase the relevance of your article.

In general, the article is interesting, dedicated to such a topical issue as the optimization of N use in vegetable cultivation and the possibilities of effective use of soil amendments such as biochar.

However, there are many inaccuracies in the article. The description of the methodology should be definitely improved. The Results section needs corrections. More attention should be paid to the correct presentation of tables and figures so that the results can be clearly understood. I recommend accepting this article in Horticulturae after major revision. Efforts should be made to improve the scientific quality of this work, as the data material obtained in this study could be of interest to both plant physiology and agricultural scientists.

Author Response

Dear reviewer,

     I have replied to all the opinions of the two experts in the cover letter

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Although the authors have significantly improved the content of the article, there are some gaps remain to be addressed.

You have answered several questions in the reply letter, but not in the text of the article. Explanations and corrections must also be included in the text.

I would recommend to indicate the aim of the research first and then the tasks to be performed for its realization.

Line 90. The region is not a climate! The experimental region has a typical temperate continental climate.

Line 140. “Plant height and stem diameter were measured every 2 days during tomatoes growth.” What was the purpose of measuring every 2 days? You answered in the cover letter but not in the text. As far as I understood from the explanation - to find out the need for the frequency of watering. Why not mention it in the manuscript?

Line 150. Tomato plants were picked or tomato fruits? You answered that fruits, but the text does not say so.

Figure 1 and Table 1

The following information like that should be indicated at the end of the Tables and Figures - values with different letters differ significantly for each plant organ or for treatment (p<0.05).

About soil pH (Table 8). You have given a good explanation in the cover letter, but not in the text.

I recommend accepting this article in Horticulturae after minor revision.

Author Response

please see the attachment

Author Response File: Author Response.pdf