FytoSol, a Promising Plant Defense Elicitor, Controls Early Blight (Alternaria solani) Disease in the Tomato by Inducing Host Resistance-Associated Gene Expression

Round 1

Reviewer 1 Report

The presented manuscript is interesting and of great practical value. The corrections made have significantly improved this article and made it more understandable for the reader. Well and clearly described Materials and Methods and Results greatly facilitate the understanding of the experiment itself and its result. This makes it possible to compare the obtained data with those previously described by other researchers. Based on this, we can recommend this manuscript for publication in this form. Of the wishes that remain at the discretion of the author and editor: slightly reduce the Abstract, make it more concise and not so voluminous so that the researcher can quickly understand what the article is about.

Author Response

Thank you very much for the input and suggestions. I revised the manuscript based on the feedbacks. Please see the attachment. 

Author Response File: Author Response.docx

Reviewer 2 Report

Manuscript title: FytoSol, a promising plant defense elicitor, controls early blight (Alternaria solani) disease in tomato by inducing host resistance-associated gene expression

 

Manuscript ID: horticulturae-1730849

 

Journal: Horticulturae

 

 

The main objectives of the current MS were (i) to investigate the effects of FytoSol and INA against early blight caused by Alternaria solani in tomato, ii) to determine the disease severity of early blight over several time points to understand elicitors’ long-lasting activity, and iii) to investigate plants response to defense elicitor applications at the molecular level for basal defense mechanism. According to the results, Fytosol significantly reduced disease severity by an average of 30% for almost one month with an AUDPC value of 399 compared to control with an AUDPC value of 546. The MS was well-written and the author proved an excellent knowledge to summarize the interesting results. Abstract is informative, material and methods contain a sufficient data and will be useful for other researchers to repeat. Some suggestions are included in the attached pdf.  

Comments for author File: Comments.pdf

Author Response

Thank you very much for the input and suggestions. I revised the manuscript based on the feedbacks. Please see the attachment. 

Author Response File: Author Response.docx

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

1. The sentences in on lines 112 - 117 refer rather to conclusions. In the introduction, this is usually not written.
2. Judging by the chapter Materials and Methods, only 5 plants participated in the experiment for each of the two treatments. Obviously, the same plants were measured at 13 dpi, 18 dpi, 23 dpi, 28 dpi, and 33 dpi after treatment. Based on this, the results obtained cannot be interpreted as reliable.
3. At the same time, the results show that no statistically significant differences were found in the assessment of leaf damage.

Reviewer 2 Report

1. In MM section, primers list should be transfer to suplementarny
2. Fig 2 change gram to g
3. Smaller charts will be more „reader-friendly”
4. Maybye add some foto of tomato treated with Fytosol and INA and infected with A.solani
5. On charts 5 d, c, e : minus lines is on charts signatures
6. Uniform font for all charts on fig 5 (especially 5e)
7. for a better understanding of the results maybye add the results for PR gene expression after INA, even if they were previously presented (fig 5g-i) – Editor decision
8. line 334 previously without italic
9. add statistical significance for gene expression analysis

Reviewer 3 Report

The author presents the evaluation of two plant-elicitor products against EB in tomato plants. The concept is adequate; however, the methodological approximation has weak points. In specific,

It is not clear how many times each assessment (experiment), either for disease severity or gene expression, was performed since the definition “at least three times” does not clarify if it was repeated three or more times and in which case(s).

It is not clear who the samples for gene expression analysis were formed. Where they individual samples from each plant or pooled, and if the latter how. Furthermore, it is not clear if sampling (leaf) refers to a composite leaf or a single one.

The gene expression analysis approach does not fully cover the scope, which is to see what happens to these genes during the period (at least one time point) plants are infected. These genes are defense associated genes as stated by the author, however, their expression is not studied post-inoculation as well. There could be further up- or down-regulation due to synergy or priming. This is missing from the experimental design. Furthermore, the level of relative expression is not indicative. Nearly all genes are downregulated by FytoSol and this is in a range (scale) which is questionable. This is a further reason why gene expression should have been studied at least in one more time point.

There is an allocation cost effect for the plants due to FytoSol application as indicated from the PFW PDW and PH measurements. This should be somehow studied (and discussed) a bit further before entering in gene expression analyses.

The negative effect of INA, though negative, could be an interesting starting point to study in parallel (with FytoSol) these effects on plant performance.

The A. solani isolate is not described appropriately.

The presentation of Figures and Legends should be improved.

References do not cover fully the field of elicitors (e.g., lines 80-81)

Minor English grammar/expression improvements are required.