Cultivar-Groups in Cucurbita maxima Duchesne: Diversity and Possible Domestication Pathways

Round 1

Reviewer 1 Report

The authors propose a manuscript titled “Cultivar-groups in Cucurbita maxima: diversity and possible domestication pathways”. The authors have evaluated have evaluated the domesticated Cucurbita that is one of the plant genus with the highest diversity in color, shape and fruit dimensions, and the wild ancestor of C. maxima ssp. andreana that has a disjoint distribution, and It was domesticated in South America around 9000-7000 years BP. The authors describe nine cultivar-groups for the species, Banana, Turban, Hubbard, Show, Buttercup, Zapallito, Plomo, Zipinka and Nugget showing Turban and Buttercup in a centrally position, suggesting a first step in domestication pathway associated to seed and immature fruit. The results on domesticated Brazilian accession MAX24 intermediate between cultigens and ssp. andreana concords with the archeological remains, and the possible more easternward domestication place of the species than previously believed. The manuscript is original in the data compared to other similar articles and is able to be published on international audience as Diversity. However I believe it is necessary to implement the manuscript with few formal concepts that the authors will have no problem to accepting as they are designed to improve the work.

Title

Line 2. Please add the author of the taxon name in the following way:

Cultivar-groups in Cucurbita maxima Duchesne: diversity and possible domestication pathways

Abstract

Line 13. The work describe instead I describe

1. Cucurbita

• Line 26. The authors statement that the genus Cucurbita is 2n = 20. Normally the chromosome number refers to a species not a genus. Are the authors sure that all species of the Cucurbita genus have the same chromosome number?. If yes please choose a refernce for this sentence.
• Lines 27-30. Please choose a reference for a general statements. “Wild species are herbaceous, multi-branched, procumbent or climbing vines (CHOOSE A REFERENCE). The stems are slender and the leaves are arranged on them alternately. Plants are monoecious and predominantly staminate, with large yellow-orange (rarely pale yellow) flowers pollinated in early morning by solitary bees of the genera Poponapis and Xenoglossa (CHOOSE A REFERENCE).
• Lines 84-85. Over the last decade, the idea that domestication was a rapid process (Holocene revolution) began to be seriously questioned [CHOOSE A REFERENCE], as observed as for example happened for the different varieties of cultivated wheat, obtained starting from the wild species of the genus Aegilops, intensively studied because of its close relationship with cultivated wheats [Perrino et al. 2014]”.

References to be added:

• Perrino, E.V., Wagensommer, R.P.; Medagli, P. The genus Aegilops (Poaceae) in Italy: taxonomy, geographical distribution, ecology, vulnerability and conservation. Systematics and Biodiversity, 2014, 12, 331-349. https://doi.org/10.1080/14772000.2014.909543

2. Cucurbita archeobotanics and 3. Cultivar-groups

• Well done, no obseravtions

4. Diversity and Domestication Pathways

Few observations. The figures are clears.

• Line 400-402. In maxima a couple studies have been conducted in order to elucidate genetic relationships among cultivars or accessions, but neither was comprehensive to include as many cultivar groups as described above nor was the ssp. andreana considered [MENTION THE TWO REFERENCES].

Reference

Please see the guidelines of the journal

Author Response

I appreciate the suggestions and corrections made by the reviewer

I provide a point-by-point response to the commnets in bold:

Title

Line 2. Please add the author of the taxon name in the following way:

Cultivar-groups in Cucurbita maxima Duchesne: diversity and possible domestication pathways: Duchesne was included

Abstract

Line 13. The work describe instead I describe: It was changed

Cucurbita

The authors statement that the genus Cucurbita is 2n = 20. Normally the chromosome number refers to a species not a genus. Are the authors sure that all species of the Cucurbita genus have the same chromosome number?. If yes please choose a reference for this sentence: A reference was inserted.

Lines 27-30. Please choose a reference for a general statements. “Wild species are herbaceous, multi-branched, procumbent or climbing vines: A reference was inserted.

The stems are slender and the leaves are arranged on them alternately. Plants are monoecious and predominantly staminate, with large yellow-orange (rarely pale yellow) flowers pollinated in early morning by solitary bees of the genera Poponapis and Xenoglossa: A reference was inserted.

Lines 84-85. Over the last decade, the idea that domestication was a rapid process (Holocene revolution) began to be seriously questioned [16], as observed in different varieties of wheat derived from Aegilops [Perrino et al. 2014]”. The paper cited [16] is a review; I believe that is not necessary to introduce specific examples in cereals, since my contribution in not regarding evolutionary pathways from a wide perspective, solely in C. maxima.

Diversity and Domestication Pathways

Line 400-402. In maxima a couple studies have been conducted in order to elucidate genetic relationships among cultivars or accessions, but neither was comprehensive to include as many cultivar groups as described above nor was the ssp. andreana considered [MENTION THE TWO REFERENCES]. The two references [69,70) were mentioned.

Reviewer 2 Report

.

Line 144: “C. maxima ssp. andreana: orange “. In map orange is C.maxima ssp maxima

Line 260: “elliytical–acorn”, is elliptical–acorn?

Line 443:  “L (Banana), L (Nugget)” , L is Banana or Nugget?

Line 445: “ar (Argentina)”, line “ar (Entre Ríos)”. Ar is Argentina or Entre Rios?

Lines 457, 466, 507: “129ukn” is 129unk?

In supplementary data in the table footnote put the names of the species in italics

“L (Banana), L (Nugget).” Is Banana o is Nugget

^{3 “}According to passporta by Genebank” change by Passport by Genbank

⁴ “Cultivargropu only” change by cultivar group

^{5 “}Only for  ssp. andreana sArgentinian” is correct the s of sArgentinian?

⁶ “Genebanks” change for Genbanks

ar is Argentina and also Entre Rios? Is possible that entre Rios is er?? (For example MAX 81 (Aer)

Accesion 56Bsd and PI234608, Star7024 what is sd? South Africa? In footnote table is so

Accesion 65cn, cn is China?, no in footnote table67ir and 77 ir is Iran? Not in footnote table

57ni, ni is Niger? Not in footnote table

54Pin, in is India? Not in footnote table

what is sf? Santa Fe? Put in footnote table please

what is tk? Turkey? Put in footnote table please

62rs, rs is Russia?  Not in footnote table

192Tsy, sy is Syria? Not in footnote table

MAX 302 is Zur, no ZuStokes or Stoke? In table Stokes, in footnote table Stoke

What is CP in source?

Please, review all the codes and the footnote tables

Author Response

I really appreciate the exhaustive reading of the manuscript and supplementary table. 

I provide a point-by-point response to the reviewer in bold: 

Line 144: “C. maxima ssp. andreana: orange “. In map orange is C.maxima ssp maxima: It was changed

Line 260: “elliytical–acorn”, is elliptical–acorn?: yes it was changed

Line 443:  “L (Banana), L (Nugget)” , L is Banana or Nugget?: Nugget is N, it was amended

Line 445: “ar (Argentina)”, line “ar (Entre Ríos)”. Ar is Argentina or Entre Rios?: Entre Ríos is er, it was corrected

Lines 457, 466, 507: “129ukn” is 129unk?: Yes all 129ukn were changed by 129unk

In supplementary data in the table footnote put the names of the species in italics

“L (Banana), L (Nugget).” Is Banana o is Nugget: It was changed, N is Nugget

3 “According to passporta by Genebank” change by Passport by Genbank: It was changed

4 “Cultivargropu only” change by cultivar group: It was corrected

5 “Only for  ssp. andreana sArgentinian” is correct the s of sArgentinian?: It was changed by the correct ssp. andreana Argentinian

6 “Genebanks” change for Genbanks: It was changed

ar is Argentina and also Entre Rios? Is possible that entre Rios is er?? (For example MAX 81 (Aer): Yes Entre Ríos is er, it was corrected

Accesion 56Bsd and PI234608, Star7024 what is sd? South Africa? In footnote table is so: yes, it was changed sd is South Africa

Accesion 65cn, cn is China?, no in footnote table67ir and 77 ir is Iran? Not in footnote table: yes all these acronyms were included an explained in the footnote of the Table

57ni, ni is Niger? Not in footnote table: Is Negeria and was added

54Pin, in is India? Not in footnote table: Yes is India and was added

what is sf? Santa Fe? Put in footnote table please: sf is Santa Fe province of Argentina, and it was explained

what is tk? Turkey? Put in footnote table please: Yes, is Turkey and was added

62rs, rs is Russia?  Not in footnote table: Yes is Russia, and was added

192Tsy, sy is Syria? Not in footnote table: Yes, is Syria and was added

MAX 302 is Zur, no ZuStokes or Stoke? In table Stokes, in footnote table Stoke: MAX302 is Zapallito from Uruguay (123Zur), it was corrected, the Seed Company is Stokes

What is CP in source?: CP was a previous Spanish acronym for FLA (accessions collected by the author), it was homogenized in all the table by FLA

Reviewer 3 Report

"Cultivar-groups in Cucurbita maxima: diversity and possible domestication pathways" is a really interesting review.

The manuscript perfectly introduces the reader to the varied scenario of this very interesting and widespread species.

Cucurbita is an evident example of the phenomenon of domestication and its distribution is proof of this. Agronomic, anthropic and commercial interest have contributed over the years to what is the current scenario. I find that the review is very well written, the author's work is really rich and full-bodied. The only thing I think I have to suggest to the author is to try to increase the experimental information mentioned in paragraph 4.

For example, at the beginning of the paragraph two works on SRAP and AFLP are mentioned but the results are not shown.

All the aspects described are very detailed and contextualized in the numerous bibliographical references. The linguistic style is clear and linear and makes the review very understandable.

Author Response

I really appreciete the comments on the article, 

I provide a point to the suggestion in bold:

The only thing I think I have to suggest to the author is to try to increase the experimental information mentioned in paragraph 4. For example, at the beginning of the paragraph two works on SRAP and AFLP are mentioned but the results are not shown: I include a Figure with the hierarchical clustering dendrogram for AFLP markers from the study of Ferriol et al 2004 [69], I believe it will increase information as suggested