Round 1

Reviewer 1 Report

The manuscript of “Influence of substrates in the development of bean and in pathogenicity of Rhizoctonia solani” by Sara Mayo-Prieto et al. investigated the effects of different substrates and additives on bean growth and disease severity, which provided some helpful information in agriculture application.

However, after reading the whole manuscript, I have one major issue to propose. I missed the mechanisms how those substrates and additives work on the bean growth and pathogen control? For example, do those substrates or additives directly inhabit pathogen? Or those additives induce changes in soil physicochemical properties or affect other microbes?

In addition, would you explain the ratio of additives (bentonite and/or cornmeal) in the substrates (vermiculite or peat)? How it works if we change or improve the ratio of additives?

The overall writing of the manuscript should be improved by the native speakers of English.

Author Response

REVIEWER 1

The manuscript of “Influence of substrates in the development of bean and in pathogenicity of Rhizoctonia solani” by Sara Mayo-Prieto et al. investigated the effects of different substrates and additives on bean growth and disease severity, which provided some helpful information in agriculture application.

However, after reading the whole manuscript, I have one major issue to propose. I missed the mechanisms how those substrates and additives work on the bean growth and pathogen control? For example, do those substrates or additives directly inhabit pathogen? Or those additives induce changes in soil physicochemical properties or affect other microbes?

We have added these characteristics in introduction and discussion.

Lines 60-70: “Inert substrates made with clay pellets, gravels, vermiculite and perlite present a lower risk of hosting pests and pathogens in plant production, that any substrate with peat, coconut fibre, bark, compost, vermicompost, wood chips, cork or moss , all which greater phytopathogen development [11]. Nutrient availability is an important criterion for soil borne saprotrophic phytopathogens to become prevalent in soils. Their possible outgrowth can be constrained by nutrients, space, etc [12–14]. Crop soils are biologically active soils, with capacity to control pathogenic infections of plants, however, this capacity is lost or reduced in the substrate of a greenhouse. The use of natural products such as organic additives is a promising alternative for managing of a diseases and for promoting the development of other beneficial microorganisms”

Lines 362-380: “The presence of an inoculum of a phytopathogen, a susceptible host and certain environmental conditions (soil, temperature, humidity, etc.) are all necessary an infection [58]. One way to control of this process is practicing crop rotation, where a resistant/tolerant plant is sown, reducing the amount of inoculum. Another way to achieve this is modifying the soil or substrate in a way that favors the development of biocontrol agents. For this, biocontrol agents can be added to the substrate mixture. If a substrate is enriched with additives that provide a source of energy for the development of beneficial organisms, it will reduce the use of synthetic chemical products, therefore producing safer foods for the consumer and for the environment. In substrates with cornmeal, Trichoderma has shown higher rates of development than without this additive. Moreover, its growth has been higher whenever it has been inoculated into a mixture with peat and not vermiculite [36]. There are some studies where the use of additive has promoted the development of both the plant and Trichoderma. Martinez-Media et al [15] checked that the formulation with bentonite – vermiculite and Trichoderma was effective in enhancing plant growth and reducing the incidence of Fusarium wilt in melon plants. In another work, Bernal-Vicente et al [16] tested some formulations with Trichoderma as liquids with spore suspension, guar gum or carboxymethylcellulose, and solids with bentonite, vermiculite and wheat bran and they verified that substrates with bentonite and vermiculite were the most effective treatments against Fusarium wilt on melon plants giving the greatest plant weight.”

In addition, would you explain the ratio of additives (bentonite and/or cornmeal) in the substrates (vermiculite or peat)? How it works if we change or improve the ratio of additives?

In discussion we have added an explain Lines 380-384 “In this study, the selection of these concentrations for bentonite (5 %) and cornmeal (2 %) is a result of a previous work, where the variations of these additives changed the development of bean plants. When these concentrations were increased, bean plants had a stunted development of both the aerial part and the root, promoting the development of saprophytic fungus and bacteria in the substrates and increasing their compaction (unpublished data).”

The overall writing of the manuscript should be improved by the native speakers of English.

Paper has been checked by native speaker of English.

Reviewer 2 Report

Dear authors,

I have studied your article and am of the opinion that it may be published in agronomy magazine. However, it will be necessary to make some changes and edit the article.Because in its current form it contains some inaccuracies and potential mistakes.

Abstract

This section is very brief. I understand that the authors were limited by the required scope of abstract, i.e. the maximum number of words. But I miss the information about the significance of the data. I recommend adding specific details, for example in presence of pathogen between individual variants of the experiment etc.

Introduction

This part is brief and clear. On the other hand, it could contain more current knowledge about on the issue of soil-borne pathogens. I recommend adding and describing either the main objective of the thesis or some hypothesis. I believe that this is necessary to improve the quality of presented work.

Material and Methods

This part of the article is very brief, so I recommend explaining some terms and adding missing information:

• Table 1 presents treatment tested and this part of the text follows the description of the variants. But it is not clear from the above information how the experiment was organized. For example, how many repetitions did you prepared? Where a control was placed, etc.I propose to add a summary of all the variations of the experiment as described in the results chapter.
• Line 112 - … The data were transformed by the formula ….. Why do you used this formula?
• The significance (? P<0.05 or P<0.01?) level is missing from the description of statistical data processing.

Results

This chapter of the article contains four graphs and two tables with results. Graphs are clear and readable, anyway, I recommend adding more information to describe these graphs. For example, how large differences were found, etc. In particular, the results of statistical analysis in Table 2 and 3 are described very briefly and should be further elaborated.

Discussions

This part of the work is well arranged and I have no major objections to it from the content point of view.

This part of the work is well arranged and I have no major objections to it from the content point of view. I can only recommend better describe trends and depending on the results and they will more comment / dispute in the discussion.

Conclusions

The conclusion is very short, additional information must be added, especially the overall evaluation of the experiment. For example, a more detailed summary of the importance of using individual substrates.

Author Response

REVIEWER 2

Dear authors,

I have studied your article and am of the opinion that it may be published in agronomy magazine. However, it will be necessary to make some changes and edit the article because in its current form it contains some inaccuracies and potential mistakes.

Abstract

This section is very brief. I understand that the authors were limited by the required scope of abstract, i.e. the maximum number of words. But I miss the information about the significance of the data. I recommend adding specific details, for example in presence of pathogen between individual variants of the experiment etc.

We have completed the abstract adding “However, the addition of cornmeal improves bean dry weight of the aerial part. So, whenever it is necessary to add additives to the substrates to improve the installation and development of a biocontrol agent, such as Trichoderma harzianum, the mix of peat and cornmeal would improve the development of both bean and biocontrol agent.

Introduction

This part is brief and clear. On the other hand, it could contain more current knowledge about on the issue of soil-borne pathogens. I recommend adding and describing either the main objective of the thesis or some hypothesis. I believe that this is necessary to improve the quality of presented work

We have put in the introduction same paragraphs explaining these characteristics.

Lines 79-86: A lot of soil-borne pathogens cause root rot disease in common bean and are a major constraint to bean production world-wide. Root rot diseases cause seedling death and poor seedling emergence Disease incidence during flowering and pod fill results in the most significant yield reductions. In common bean, the primary diseases and pathogens associated with root rot include: Fusarium root rot, caused by Fusarium solani (Mart.) Sacc. f. s, phaseoli (Burkholder) W. C. Snyder & H. N. Hans; southern blight, caused by Sclerotium rolfsii Sacc; Pythium root rot, caused by several species of Pythium spp.; Aphanomyces root rot, caused by Aphanomyces euteiches f. sp. phaseoli and f. sp. pisi, and Rhizoctonia root rot, caused by Rhizoctonia solani JG Kühn [26–29].

The main objective of this work is to determine the influence of horticultural substrates and additives combinations in development of bean plantlets and in pathogenicity of Rhizoctonia solani (Lines 94-96)

Material and Methods

This part of the article is very brief, so I recommend explaining some terms and adding missing information:

Table 1 presents treatment tested and this part of the text follows the description of the variants. But it is not clear from the above information how the experiment was organized. For example, how many repetitions did you prepared? Where a control was placed, etc. I propose to add a summary of all the variations of the experiment as described in the results chapter.

In lines 123-124 and 136, we have described that it was used 10 repetitions per treatment. We have changed the title of the table remaining “Table 1: Substrates and their combinations tested in order to R. solani pathogenicity”. The control treatments were placed in the same climate chambers that the others treatments (line 131-132).

Line 112 - … The data were transformed by the formula ... Why do you used this formula?

In lines 149-159, we have added "The data were transformed by the formula for their normalization”. Square-Root Transformation is appropriate for data consisting of small whole numbers, for example, date obtained in counting rare events, such as the number of infested plants in a plot. For these data the variance tends to be proportional to the mean. The square root transformation is also appropriate for percentage data (Gomez y Gomez, 1984; Valenciano et al., 2006).

The significance (P<0.05 or P<0.01?) level is missing from the description of statistical data processing.

The significance level is specified in tables and in figures.

Results

This chapter of the article contains four graphs and two tables with results. Graphs are clear and readable, anyway, I recommend adding more information to describe these graphs. For example, how large differences were found, etc. In particular, the results of statistical analysis in Table 2 and 3 are described very briefly and should be further elaborated.

We have added in the description of both tables “for germination in 12, 17 and 24 days after sowing, disease severity 45 after sowing, and dry weights of aerial part and root system”. Furthermore, we have rewritten the results.

Discussions

This part of the work is well arranged and I have no major objections to it from the content point of view. I can only recommend better describe trends and depending on the results and they will more comment / dispute in the discussion.

We have added information to help the explanation and to favor its interpretation.

Conclusions

The conclusion is very short, additional information must be added, especially the overall evaluation of the experiment. For example, a more detailed summary of the importance of using individual substrates.

We have added some sentences for complete the conclusion. “. However, the addition of cornmeal improved bean dry weight of the aerial part. Therefore, whenever it is necessary to use additives in the substrates to improve the installation and development of a biocontrol agent, such as T. harzianum [36], the mix of peat and cornmeal would improve the development of both bean and biocontrol agent”.

Round 2

Reviewer 1 Report

Current version is improved, I have no further comments.