Bacterial and Fungal Communities of Table Grape Skins in Shanghai
, Qingchuan Ma 1, Sijie Sun 2, Hengcheng Zhang 3, Chenang Lyu 1,*, Dapeng Wang 1 and Shiren Song 1,*Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Authors,
Your paper entitled: "Bacterial and Fungal Communities of Table Grapes" is interesting, well written and well presented. There are some minor English language issues especially the use of articles (A/The).
However, there is an issue with the title where you lead the reader to expect a study on bacterial and fungal biodiversity. But your results are 80% fungi and almost nothing about the bacterial taxa. Inferences are made about the the function of bacterial taxa but the biodiversity is not properly described nor discussed.
The reader is led to expect a comparison of isolated microbes with PCR-DNA amplified biodiversity. This is also slightly misleading.
Very few results are shown for the isolated unicellular fungi (yeast) and nothing is said about isolated filamentous fungi and nothing about isolated bacteria. That noted the data that you did present is very interesting and the reasons for your study are also interesting and important.
As I said the paper is generally very well written but the title is wrong. My suggestion is you change the title and focus solely on the fungal / yeast results. I have copied what you wrote about bacterial diversity beneath:
"In total, we have identified 252 fungi and 594 bacteria genera from collected grapes. The fungal population was on average dominated by Cladosporium (57.5%), followed by Aspergillus (16.6%), Alternaria (10.9%) and Zygosporium (4.9%). The bacterial population was on average dominated by unknown bacterial genera (32.7%), Thauera (22.8%) and 148 Pantoea (17.3%)
I would like to have read more in the discussion from the above results. For example: about the fungi, how many were yeast? Of the yeast that were identified by sequencing how many were also cultivated? How did your cultivated yeast/fungal diversity compare with the DNA-PCR community? Do the yeast we can see with our eyes growing on grapes not dominate the DNA-PCR community results? If not, why not? I think it would have been nice to comment how the yeasts you found can contribute to flavour. Where were the Sacchoromyces? About your bacterial results: 32.7% not known at genus level? I am confident that you had a better way of describing this result at a higher taxonomic level - which families did they belong too?
What I found interesting is that just two genera accounted for 40% of the bacterial communities. Did this result repeat for both grape varieties and at all locations? Thauera strains are known to be metabolically versatile and Pantoea strains are considered to be of plant origin. Should they now be known as grape skin bacteria? If so they must have developed strategies to deal with yeast competition and might impact on flavour!
I would recommend that you change the title reformulate the paper and focus on just the fungi/yeast. I would discuss more what the dominant genera might be doing in relation to grape longevity and flavour. If you choose to describe the bacteria, then you need to include much more information and discussion on the bacteria.
Thank you for the opportunity to review your work
Comments on the Quality of English Language
Some very minor changes would improve the text.
Author Response
Response to reviewer 1 has been uploaded.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsI always encourage the researches which use modern technology such as high-throughput sequencing technologies to resolve some issues in microbial ecology. Understanding the fungal and bacterial communities on grape skin is good example of this practise. In that sense I agree with publication of this manuscript to the Journal "Horticulturae". However, the manuscript has some shortcomings.
So, why authors chose to isolate only yeasts, but not filamentous fungi? Are grape skin considered to be potential reservoir of pathogenic yeasts? If so, the reason for yeast isolation must be better explained in the goals of the research. Also, some good discussion regarding the yeast presence on the would improve the manuscript.
The ecological role of the most abundant fungi and bacteria is not properly discussed. Are there any potential plant pathogens detected? Can the presence of Alternaria and Acremonium affect somehow the Vitis vinifera cultivars?
Mycobiota profile showed the presence of the members of genus Botrytis. with high relative abundance. I think the presence of Botritys spp. on grapes is much more important then presence of yeasts. Ecology and role of B. cinerea on grapes should be better discussed.
I suggest using graph charts in order better to present the compositon of grape microbiota in Result Section.
Some specific comments:
Line 162: Write Aspergillus in italic
Line 247: Write Thauera and Pantoea in italic
Line 254: Also, write Rhodotorula mucilaginosa in italic
Author Response
Response to reviewer 2 has been uploaded.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Authors,
Thank you for your revision. I note that you have answered all the questions that I raised in the first review. You maintained and improved the bacterial data and analyses in your paper and because of this, I have suggested a new title that includes bacteria. Please check the document attached. I have made corrections to the English (concerning articles) I have substituted the expression "current study" on numerous occasions it was overly repeated. My new suggestions are in RED text. I have made numerous changes to the English in the abstract, introduction, and conclusion which I believe will improve understanding.
I am happy to trust that you will make the necessary changes and hope to the paper after it is published.
Comments for author File: Comments.pdf
I have made corrections to the English directly in the text. This should help the authors make corrections (see attached document).
Author Response
Response has been attached.
Author Response File: Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsI read the revised version along with authors' comments and I think, the Manuscript is now improved. So, I agree with the publication.
Author Response
Response has been attached.
Author Response File: Author Response.pdf
