Screening of Rhizosphere Microbes of Salt-Tolerant Plants and Developed Composite Materials of Biochar Micro-Coated Soil Beneficial Microorganisms

Round 1

Reviewer 1 Report

In this work, the authors did a screening of beneficial microorganisms in the rhizosphere of salt-tolerant plants and developed composite materials of biochar micro-coated soil beneficial microorganisms. The overall manuscript is good. however, some of the minor corrections are:

1. Keywords should be at least 5

2. Title is very long

3. Give references to the screening method followed.

4. Figures 4, 5, and 8 are not clear.

5. Statistical analysis of results should be done.

Author Response

Thanks so much for your suggestions of the reviewer, and have responded to all the comments, as shown below：

1. Keywords should be at least 5

• A: Thank you very much for your valuable suggestions, which have been revised. Please See page 1, line 24.

2. Title is very long

• A: Thank you very much for the valuable suggestions of the committee member, and the Title has been shorten, line 2 to 4.

3. Give references to the screening method followed.

• A: Thank you very much for the valuable suggestions of the committee members, and the references to the screening method was given See page 2, line 92.

4. Figures 4, 5, and 8 are not clear.

• A: Thank you very much for your valuable suggestions. Figures 4, 5, and 8 are enlarged. See page 6-8, line 206-216.

5. Statistical analysis of results should be done.

• A: Thank you very much for your valuable suggestions. This paper mainly discusses the phenomenon, because the data volume of the repeated number test is insufficient, so no further statistical analysis is carried out.

Author Response File: Author Response.pdf

Reviewer 2 Report

small remarks in the attached file

Comments for author File: Comments.pdf

Author Response

Thanks so much for your suggestions of the reviewer, and have responded to all the comments, as shown below：

1. Line 81. 2. Materials and Methods. What type of salinity is the soil?

• A: Thank you very much for your valuable suggestions. The salinity soil is sandy loam in the Penghu of Taiwan.

2. Line 149 After mixing with crushed oyster shells at 1:1 (w/w)... Why did the mixing take place?

• A: Thank you very much for your valuable suggestions. After the activation test, this ratio could meet the needs of meso- and macro- pore biochar in the development, and it is also the most economical.

3. Line 245-248. At the same time, when helping crops to survive the stress of salinity, the biochar produced in this experiment is not mainly to improve the soil effect, so it can be indirectly confirmed that the main reason for improving the growth of crops is from beneficial microorganisms. Can give an example of how microorganisms work in this case?

• A: Thank you very much for your valuable suggestions.

Observed for 28 days after inoculation and counted the morbidity of tomato wilt disease (Figure 16), it was found that the morbidity of the samples treated with the composite material (Bacillus amyloliquefaciens + biochar) was the lowest, and only low-er leaf yellowing occurred. In the treatments of adding water and biochar, the lower leaves died, the upper leaves withered, and the plants were lodging, but no complete plant death was found after 28 days. In addition, the disease degree of the biochar group was slightly higher than that of the water-added control group in the early stage of disease. It is speculated that because the biochar is not coated with microorganisms, the nutrients absorbed by itself can be used and grown by pathogenic bacteria, result-ing in a high disease degree in the initial stage of the biochar treatment. The verifica-tion test results and analysis of the crop control effect of biochar-based biological ferti-lizers or preparations showed that the composite material treatment can effectively reduce the disease degree of tomato by 69.43% compared with water treatment (Figure 17).

Not: Bacillus amyloliquefaciens, the mechanism of preventing and controlling crop diseases includes the production of a variety of antimicrobial substances, such as iturin A, surfactin and fengycin, which can inhibit the growth of pathogenic bacteria; The hyphae can be entangled in the plant rhizosphere and induce a defense response in the plant to resist the invasion of pathogenic microorganisms.

Author Response File: Author Response.pdf

Reviewer 3 Report

Abstract: needed to rewrite, as order as Aim, methods, results, and conclusions;

Introduction:

Line 27-30, 30-32 point out references;

In the introduction, the references should be listed closely related to the research work;

In materials and methods: each method needed to list the reference/s, or an original method needed to describe in detail and the academically acceptable explanation.

Line 253, the original pH should be listed;

Discussion: Generally the data and results could be discussed with other research works.

 Author Response

Thanks so much for your suggestions of the reviewer, and have responded to all the comments, as shown below：

1. Abstract: needed to rewrite, as order as Aim, methods, results, and conclusions;

A: Thank you very much for your valuable suggestions. Abstract was rewritten as your suggestions, Line 13-23.

2. Introduction: Line 27-30, 30-32 point out references; In the introduction, the references should be listed closely related to the research work;

A: Thank you very much for your valuable suggestions. Reference was added closely related to the research work as your suggestions, Line 29-31.

3. In materials and methods: each method needed to list the reference/s, or an original method needed to describe in detail and the academically acceptable explanation.

A: Thank you very much for your valuable suggestions. Reference was added as your suggestions. Line 92,108,120,125,130,135,140, 154.

4. Line 253, the original pH should be listed;

A: Thank you very much for your valuable suggestions. Original pH was listed in Table 5 Line 254.

5. Discussion: Generally the data and results could be discussed with other research works.

A: Thank you very much for your valuable suggestions.

Discussion was modified as your suggestions: Line 327-331, References [31] [32]; Line 226, Reference [33].

Author Response File: Author Response.pdf

Reviewer 4 Report

Manuscript entitled "Screening of beneficial microorganisms in the rhizosphere of salt-tolerant plants and developed composite materials of biochar micro-coated soil beneficial microorganisms" submitted to Sustainability journal is well written and the results are presented in a logical and coherent manner.

The paper is adequately organized and the topic is interesting and focuses on elaboration a composite material of biochar micro-coated soil beneficial microorganisms was developed, which is extremely important for sustainable agricultural management.

Although the manuscript is well-edited, however small improvements should be introduced that will improve its quality: 

Line 33: References to literature are not ordered - the first one is number [27], and for example number [20] I did not find in the text.

Figures 1-3: are not legible. If they were better resolution they would be more available.

Tables 4 and 5: Data should be provided as three significant digits. Two decimal places are necessary only for a one-digit value (less than 10), e.g. in Table 4 only for the values N P and K. For data: Mn and Zn, precision to one decimal place is enough (these are three significant digits). And for: Ca, Mg, Fe and Na no accuracy below whole numbers is needed (the value is three digits or more).

Table 7: the abbreviation SPAD should be expanded in the footnotes directly below the table.

Figures 4-8 and 15. should also have better quality

Conclusions are too general described, more like a summary. In addition, they go beyond the scope of the results obtained and contain assumptions (e.g. The composite material /..../ CAN effectively improve plant growth, help crops resist adverse environments and slow down the occurrence of diseases, and ....). Such formulation of conclusions is not correct, either a fact is stated on the basis of conducted research, or conjectures are made. Therefore, the Conclusions should therefore be redrafted

Author Response

Manuscript ID: sustainability-2018685: Screening of beneficial microorganisms in the rhizosphere of salt-tolerant plants and developed composite materials of biochar micro-coated soil beneficial microorganisms

Manuscript entitled "Screening of beneficial microorganisms in the rhizosphere of salt-tolerant plants and developed composite materials of biochar micro-coated soil beneficial microorganisms" submitted to Sustainability journal is well written and the results are presented in a logical and coherent manner.

The paper is adequately organized and the topic is interesting and focuses on elaboration a composite material of biochar micro-coated soil beneficial microorganisms was developed, which is extremely important for sustainable agricultural management.

Although the manuscript is well-edited, however small improvements should be introduced that will improve its quality:

Thanks so much for your suggestions of the reviewer, and have responded to all the comments, as shown below：

1. Line 33: References to literature are not ordered - the first one is number [27], and for example number [20] I did not find in the text.

A: Thank you very much for your valuable suggestions. All references have been listed in sequential order to match the order of the article.

2. Figures 1-3: are not legible. If they were better resolution they would be more available.

A: Thank you very much for your valuable suggestions. Figures 1-3: Figure have improved quality and increased DPI (increase resolution).

3. Tables 4 and 5: Data should be provided as three significant digits. Two decimal places are necessary only for a one-digit value (less than 10), e.g. in Table 4 only for the values N P and K. For data: Mn and Zn, precision to one decimal place is enough (these are three significant digits). And for: Ca, Mg, Fe and Na no accuracy below whole numbers is needed (the value is three digits or more).

A: Thank you very much for your valuable suggestions. Data was revised as your suggestions. Line 252 to 254.

4. Table 7: the abbreviation SPAD should be expanded in the footnotes directly below the table.

A: Thank you very much for your valuable suggestions. SPAD was expanded in the footnotes directly below the table. Line 387 to 388.

5. Figures 4-8 and 15. should also have better quality

A: Thank you very much for your valuable suggestions. Figures 4-8 and 15: Figure have improved quality and increased DPI (increase resolution).

6. Conclusions are too general described, more like a summary. In addition, they go beyond the scope of the results obtained and contain assumptions (e.g. The composite material /..../ CAN effectively improve plant growth, help crops resist adverse environments and slow down the occurrence of diseases, and ....). Such formulation of conclusions is not correct, either a fact is stated on the basis of conducted research, or conjectures are made. Therefore, the Conclusions should therefore be redrafted

A: Thank you very much for your valuable suggestions. Conclusions was redrafted as your suggestion. Line 410-425.

Author Response File: Author Response.pdf

Reviewer 5 Report

Reviewer

MDPI – Sustainability

Manuscript Number: sustainability-2018685

Title: «Screening of beneficial microorganisms in the rhizosphere of salt-tolerant plants and developed composite materials of biochar micro-coated soil beneficial microorganisms».

The article is devoted to a very interesting and useful topic for sustainable agriculture. Inoculation on biochars of various origins of bacteria can improve the morphological characteristics of plants and increase yields.

line 80 It is necessary to formulate the purpose of writing the article.

line 84. Which salt-tolerant plants have been studied?

line 215-217 Transfer this information about raw materials for the production of biochar to the methodology

Comments for author File: Comments.pdf

Author Response

Thanks so much for your suggestions of the reviewer, and have responded to all the comments, as shown below：

1. line 80 It is necessary to formulate the purpose of writing the article.

• A: Thank you very much for your valuable suggestions. The purpose of this article was added. See page 2, line 81-82.

2. line 84. Which salt-tolerant plants have been studied?

• A: Thank you very much for your valuable suggestions. Ice flower was added, see page 2, line 86.

3. line 215-217 Transfer this information about raw materials for the production of biochar to the methodology

• A: Thank you very much for your valuable suggestions. Material and methods are revised as your suggestion. See page 5, line 148-150.

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

The first sentence is not complete. please check all grammar errors.

Comments for author File: Comments.pdf

Author Response

Manuscript ID: sustainability-2018685: Screening of rhizosphere microbes of salt-tolerant plants and developed composite materials of biochar micro-coated soil beneficial microorganisms

Round 2, Reviewer 3

 Thanks so much for your suggestions of the reviewer, and have responded to all the comments, as shown below：

1. Line 13-14: The first sentence is not complete. Please check all grammar errors.

A: Thank you very much for your valuable suggestions. The first sentence was revised as your suggestions. Line 13-14.

Author Response File: Author Response.pdf