Genetic diversity of Ethiopian cocoyam (Xanthosoma sagittifolium (L.) Schott) accessions as revealed by morphological traits and SSR markers

Eyasu Wada; Tileye Feyissa; Kassahun Tesfaye; Zemede Asfaw; Daniel Potter

doi:10.1371/journal.pone.0245120

Peer Review History

Original SubmissionAugust 4, 2020
26 Aug 2020 Decision Letter - Tzen-Yuh Chiang, Editor PONE-D-20-24312 Genetic diversity of Ethiopian cocoyam (Xanthosoma sagittifolium (L.) Schott) accessions as revealed by morphological traits and SSR markers PLOS ONE Dear Dr. Wada, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Oct 10 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols We look forward to receiving your revised manuscript. Kind regards, Tzen-Yuh Chiang Academic Editor PLOS ONE Journal Requirements: When submitting your revision, we need you to address these additional requirements. 1. Please ensure that your manuscript meets PLOS ONE's style requirements, including those for file naming. The PLOS ONE style templates can be found at https://journals.plos.org/plosone/s/file?id=wjVg/PLOSOne_formatting_sample_main_body.pdf and https://journals.plos.org/plosone/s/file?id=ba62/PLOSOne_formatting_sample_title_authors_affiliations.pdf 2. Thank you for stating the following in the Acknowledgments Section of your manuscript: "This study was supported by a grant from the DAAD, Wolaita Sodo University and Department of Plant Sciences of University of California-Davis. We thank Areka Agricultural Research Center for experimental field and USDA for SSR fragment analysis. We appreciate the help of Dr. Asfaw Kifle during collection of accessions and during field works." We note that you have provided funding information that is not currently declared in your Funding Statement. However, funding information should not appear in the Acknowledgments section or other areas of your manuscript. We will only publish funding information present in the Funding Statement section of the online submission form. Please remove any funding-related text from the manuscript and let us know how you would like to update your Funding Statement. 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Please see our Supporting Information guidelines for more information: http://journals.plos.org/plosone/s/supporting-information. [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Partly Reviewer #2: Partly ******** 2. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: No ****** 3. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: No Reviewer #2: Yes ****** 4. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: Yes Reviewer #2: No ****** 5. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: The genus Xanthosoma includes three important food species: X. sagittifolium, X. atrovirens and X. violaceum. Another species, X. brasiliense, is grown for its edible leaves. Xanthosoma sagittifolium is a robust plant reaching heights of 2 m or more. The major difference between it and taro is in leaf shape. Xanthosoma spp. have sagittate leaves, while Colocasia spp. have peltate leaves. There is a sentence in the introduction explaining that in Ethiopia the two are considered synonyms. This is very confusing because the reader has the feeling that while collectiong germplasm, the authors might have collected Colocasia as well. Leaves of Xanthosoma are thick and long-petioled, with the main vein at the lower side of either basal lobe being marginal as it joins the petiole. The leaves are arrow-shaped with sharp tips and deep, wide basal lobes and a prominent marginal vein. Leaf petioles can be more than 2 m long, with blades more than 1 m long and up to 0.7 m wide. Usually the corm of such plant is about 10 to 15 cm in diameter but here diameter of 5-6 cm are reported which is shedding doubts about the species involved. The authors need to provide a table with the passport data and the information on the voucher spécimens deposited in their National Herbarium. This is common practice when diversity studies are conducted to avoid confusion and possible doubts about the Identity of the material analysed. But the paper lacks a scientific question. At the moment this is a diversity study of an american species (only one or several Xanthosoma sp?) introduced in Ethiopia using molecular markers. It appears that there is significant variation but there is no explanation for it, except that different genotypes may have been introduced. The authors are therefore invited to: Clarify their objective, elaborate on the hypotheses they want to test Provide more details and passport data on their material Clarify the identity of their material, is only one Xanthosoma species involved or several? provide a map indicating where the accessions were collected improve the quality of the dendrograms, the figures are blurry and difficult to read Reviewer #2: In this study 100 cocoyam accessions were collected from five regions in Ehtiopia, after which they were multiplied and then planted in a single trial which was used for descriptive characteristics and SSR analysis. The environment as well as season has a highly significant influence on the expression of plant characteristics. A plant could look very different when grown in two environments and when evaluated in different seasons. Therefore to do any meaningful characterization of morphological traits in order to determine genetic diversity, multiple environments and seasons should be included in the study, otherwise the data is simply nor reliable. Other comments: One assumes from the tables that two replications were used in the field trial? This should be described more clearly. ****** 6. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: Yes:** Vincent Lebot Reviewer #2: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. https://doi.org/10.1371/journal.pone.0245120.r001
Revision 1
16 Oct 2020 Author Response Response to Reviewers First we would like to thank the reviewers for taking their time to give us these constructive comments. We have replied to the comments as follows: • Response to general comments o Our manuscript have been carefully checked and revised as needed according to the PLOS ONE’s style requirements. o The financial disclosure statement is changed and the cover letter is updated o Figure files are resubmitted carefully checking PLOS ONE requirements of figure files o ORCID included o Captions for supporting information files are included at the end of the manuscript and in text citations are updated Reply to reviewer’s comment Reviewer #1 • Clarify objective and elaborate hypothesis. o Objective is clarified and hypothesis is elaborated • Provide passport data? o Provided as supplementary information (S1 Table. Passport data) • Provide Map? o Provided • Improve Quality of dendograms and figures? o Improved • A reader may be confused about our study materials and feel that Colocasia might have been included because of a sentence in the introduction explaining that in Ethiopia the two species are considered synonymous. o We have edited the sentence and clarified it to avoid any confusion • Size and diameter of corm? o The size and diameter of Xanthosoma corm is 10 to 15 cm in diameter but here the average diameter of corm recorded from 3 replication for two years experiment were 4.29 to 7.73 cm and the overall mean was 5.70 cm. Such difference may be due to: 1) Cocoyam is a perennial plant, but for practical purposes, the corm and cormles were intentionally measured separately at the end of 12th months after plantation (annually). This annual harvest could be the reason for the size and diameter reduction. Actually, we encountered larger sized corm at some fields where cocoyam grown as perennial crop when we were collecting germplasms, but which was not at research field (where it was cultivated annually). 2) The soil type of the experimental site could be another reason. • One or several Xanthosoma species? o In general, the division of the genus Xanthosoma into species has been difficult [1]. There is much confusion, discrepancies and uncertainties regarding the taxonomy of Xanthosoma at the species level. Various names have been used synonymously [2-3], the same plant being given more than one species name [4]. Thus, the name of Xanthosoma sagittifolium (L.) Schott has usually been given to the most cultivated members of this genus (Giacometti and [5-6]. In the course of this study, we refer to the accepted species status of X. sagittifolium in The Plant List [2] in the Araceae family [6], which does not tackle taxonomy in further detail. o There was no substantial evidence to say that there were different Xanthosoma species in Ethiopia although qualitative morphological traits and SSR markers clustered accession into two groups. We have a plan to do taxonomic study on Xanthosoma species in Ethiopia. Generally, the taxonomy of Xanthosoma needs to be reconstructed. 1. Saborio, F. (2007). Cocoyam (Xanthosoma sagittifolium (L.) Schott). In: Breeding of Neglected and Underutilized Crops, Spices and Herbs, pp. 172-189, (Ochatt, S. and Jain, S.M., eds). Science Publishers, USA. 2. The Plant List (http://www.theplantlist.org) 3. Lim, T.K. (2015). Edible Medicinal and Non-Medicinal Plants. Volume 9: Modified Stems, Roots, Bulbs. New York: Springer. 4. O’Hair, S.K. and Maynard, D.N. (2003). Edible aroids. In: Encyclopedia of Food Science and Nutrition, PP. 5970-5973, (Trugo, L.C. Finglas, P.M. Belton, P. Ottaway, P.B., Bressani, R., et al., eds). Academic press, USA. 5. Giacometti, D.C. and Leon, J. (1994). Tannia, yautia (Xanthosoma sagittifolium). In: Neglected Crops 1492 from Different Perspectives, pp. 255–258, (Hernandez-Bermejo, L., ed). Food and Agricultural Organization of United the United Nations, Rome, Italy. 6. Govaerts, R., Frodin, D.G. and Bogner, J. (2002). World checklist and bibliography of Araceae (and Aroraceae). Royal Botanic Gardens, UK. Reviewer #2 • Design and Replication? o Similar sized cormel germplasms were sampled from five Zones. Then, characterized using morphological traits by planting in a common research garden in 10x10 simple lattice square design for two years. This is now clarified in the methodology. o The genotype by environmental interaction (GXE) evaluation is the next plan to be done. Therefore, multilocational trials is to be conducted in different agroecology to assess the magnitude of genotype x environment (GXE) interaction and to identify stable genotypes and evaluate their performance, selecting some genotypes from the clustered accessions to evaluated yield and yield related traits. Reviewer #3 � Data availability o All data made to be available either as part of manuscript in table or as supplementary materials. This is also preferred comment from other two reviewers � Manuscript presentation o Some improvements were made on the presentation of the paper as needed � Objective and Hypothesis o Objective is clarified and hypothesis is elaborated � Sample collection zones o The accessions that were collected from the same zone were considered as one population for the genetic diversity studies in assumption that cormel germplasms were more likely shared within zones than among zones. The same language is spoken within the zones and there are frequent local markets within zones where local people buy and sell commodities. This is added in the methods and material section for clarity Results � 3.1 Start the result section with clear finding o Edited to meet the reviver’s comment � 3.2 Please don’t start a sentences with a Table o The comment is accepted and corrected � I would combine Table 2 and Table 3, emphasis to statistical significant character o The comment accepted and the two tabled combined. Emphasis was given to statistical significant character, where statistical comparison was made at p= 0.05, 0.01 and 0.001 � 3.3 Please mention the link to Table 4 early in the text o The link to table 4 is mentioned early in the text � Please check data and recalculate data for Ho =1 o Data checked and recalculated for Ho =1 for two loci (mXsCIR22 and mXsCIR27) (Table 3) and six SSR markers presented Ho values higher than He values. SSR markers, which we have used were initially identified by Cathebras et al. [1], gave variable degrees of heterozygosity, observed at levels ranging from 0.00 to 0.97. This excess in heterozygotes might be due to high rates of asexual reproduction in cocoyam due to vegetative propagation. The inflorescence of cocoyam is protogynous [2]. 1. Catherbras C. Traore C. Malapa R. Risterucci A. Chair H. characterization of microsatellites in Xanthosoma sagittifolium (Araceae) and cross-amplification in related species. Appl Plant Sci. 2014; 2(6); 2(6):129-134 http://doi.org/10.3732/apps.1400027. 2. Manner HI. Farm and forestry production and marketing profile for Tannia (Xanthosoma spp.). In: Elevitch CR, editor. Specialty Crops for Pacific Island Agroforestry. Permanent Agriculture Resources, Hawaii, USA; 2011. pp. 1-16. � How many samples from each population o Twelve to twenty eight accessions were sample from each zone. We clarified this now in the methodology section and the accessions passport data is presented as supplementary information (S1 Table 1) according the reviewer #1 and Reviewer #2 comments � 3.4 Don’t repeat the values in the Table, extract the most important findings o Comment accepted accordingly � 3.5 is not worth a separate chapter. Please combine with the previous o Combined and the main finding is interpreted at the discussion section � 3.6 Is this clustering of accessions separate from the morphological analysis? o No, clusters were done by using both morphological and SSR markers data. The results were presented by Fig. 2 and Fig. 3 to see how one goes with the other. It was seen that the second larger cluster (C-III) was contained 27 (27%) of the total accessions. Of the 27 accessions grouped in this cluster, 25 (92.3%) were purple-cocoyam accessions (Fig 2). This result was obtained by using data of morphological genetic traits. Molecular data was also grouped almost all purple-cocoyam accessions in one cluster and the green ones in another cluster (Fig.2), supporting the morphological data. These results were presented in the result section and possible reasons for this were explained in the discussion section. � In M&M it was not explained why clustering seems to be important o Checked and explained � How clustering was conducted o The following sentences are in the M&M which explain how clustering of accession were conducted. • The quantitative morphological traits were subjected to a cluster analysis using Minitab17.1, which was conducted by employing average linkage clustering strategy of the observation. Variables were standardized to a common scale by subtracting the means and dividing by the standard deviation. The number of clusters was determined by following the steps recommended by Minitab 17.1. The dendrogram showing the Euclidean distance between clusters was constructed by plotting the results of cluster analysis using the same program. • The genetic clustering based on SSR data was assessed by performing using neighbour joining algorithm implemented in the computer program PHYLIP version 3.6 using Nei’s genetic distance based on the frequencies generated by using MSA version 4.05. Discussion � is too descriptive, several values that were mentioned in the result section were mentioned again, the discussion must be shortened, taxonomic conclusion need to be drawn o These comments were considered carefully and corrected accordingly. Attachments Attachment Submitted filename: Response to reviewers.docx https://doi.org/10.1371/journal.pone.0245120.r002
6 Nov 2020 Decision Letter - Tzen-Yuh Chiang, Editor PONE-D-20-24312R1 Genetic diversity of Ethiopian cocoyam (Xanthosoma sagittifolium (L.) Schott) accessions as revealed by morphological traits and SSR markers PLOS ONE Dear Dr. Wada, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Dec 21 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols We look forward to receiving your revised manuscript. Kind regards, Tzen-Yuh Chiang Academic Editor PLOS ONE [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #1: All comments have been addressed Reviewer #2: All comments have been addressed ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #1: Partly Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #1: Yes Reviewer #2: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #1: No Reviewer #2: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #1: No Reviewer #2: No ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #1: Xanthosoma sagittifolium is an allogamous species of American origin which does not set fertile seeds in farmers' fields in Ethiopia. Therefore, all genotypes have been clonally introduced. The authors should identify the number of multilocus genotypes (MLGs) and discuss the possible number of distinct clonal lineages before concluding that there is enough genetic diversity and the have not attempted to conduct crosses. What is the number of triploids in the introduced clones ? Triploids being useless for breeding purposes, this reduce the useful genetic diversity. Reviewer #2: There are still numerous language and writing errors. It is strongly recommended that the paper be professionally language edited. I have tried to correct as many as possible errors in the attached pdf. ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review?** For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #1: No Reviewer #2: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. Attachments Attachment Submitted filename: PONE-D-20-24312_R1.pdf https://doi.org/10.1371/journal.pone.0245120.r003
Revision 2
25 Nov 2020 Author Response Response to Reviewers First we would like to thank the reviewers for taking their precious time to give us constructive comments. We have replied to the comments as follows: • Reply to reviewer’s comment o Our manuscript has been carefully checked per the PLOS ONE’s style requirements Reviewer #1 1. Data availability? o All available data, underlying the findings described in our manuscript, are provided as part of the manuscript and its supporting information files, without restriction. 2. The authors should identify the number of multilocus genotypes (MLGs) and discuss the possible number of distinct clonal lineages before they attempt to conduct crosses. o We have edited our conclusion and further plan according to this reviewer comment Reviewer #1 and Reviewer #2 1. There are language and writing errors o We would like to thank reviewer #2 for the given corrections. We have accepted the corrections accordingly and further professionally editing was also done per the recommendation forwarded by reviewer #2 Attachments Attachment Submitted filename: Response to reviewers.docx https://doi.org/10.1371/journal.pone.0245120.r004
11 Dec 2020 Decision Letter - Tzen-Yuh Chiang, Editor PONE-D-20-24312R2 Genetic diversity of Ethiopian cocoyam (Xanthosoma sagittifolium (L.) Schott) accessions as revealed by morphological traits and SSR markers PLOS ONE Dear Dr. Wada, Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process. Please submit your revised manuscript by Jan 25 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file. Please include the following items when submitting your revised manuscript: A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'. A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'. An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'. If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter. If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols We look forward to receiving your revised manuscript. Kind regards, Tzen-Yuh Chiang Academic Editor PLOS ONE [Note: HTML markup is below. Please do not edit.] Reviewers' comments: Reviewer's Responses to Questions Comments to the Author 1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation. Reviewer #2: All comments have been addressed ******** 2. Is the manuscript technically sound, and do the data support the conclusions? The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented. Reviewer #2: Yes ****** 3. Has the statistical analysis been performed appropriately and rigorously? Reviewer #2: Yes ****** 4. Have the authors made all data underlying the findings in their manuscript fully available? The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Reviewer #2: Yes ****** 5. Is the manuscript presented in an intelligible fashion and written in standard English? PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here. Reviewer #2: Yes ****** 6. Review Comments to the Author Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters) Reviewer #2: There are still some small writing and language errors that need correction. They are indicated on the attached pdf. ****** 7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files. If you choose “no”, your identity will remain anonymous but your review may still be made public. Do you want your identity to be public for this peer review?** For information about this choice, including consent withdrawal, please see our Privacy Policy. Reviewer #2: No [NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.] While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step. Attachments Attachment Submitted filename: PlosOneDec20.pdf https://doi.org/10.1371/journal.pone.0245120.r005
Revision 3
19 Dec 2020 Author Response • A reviewer comment: There are still some small writing and language errors that need correction. They are indicated on the attached pdf. • Response: We would like to thank the reviewer for the given corrections. We have included the corrections. https://doi.org/10.1371/journal.pone.0245120.r006
23 Dec 2020 Decision Letter - Tzen-Yuh Chiang, Editor Genetic diversity of Ethiopian cocoyam (Xanthosoma sagittifolium (L.) Schott) accessions as revealed by morphological traits and SSR markers PONE-D-20-24312R3 Dear Dr. Wada, We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements. Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication. An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org. If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org. Kind regards, Tzen-Yuh Chiang Academic Editor PLOS ONE Additional Editor Comments (optional): Reviewers' comments: https://doi.org/10.1371/journal.pone.0245120.r007
Formally Accepted
28 Dec 2020 Acceptance Letter - Tzen-Yuh Chiang, Editor PONE-D-20-24312R3 Genetic diversity of Ethiopian cocoyam (Xanthosoma sagittifolium (L.) Schott) accessions as revealed by morphological traits and SSR markers Dear Dr. Wada: I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department. If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org. If we can help with anything else, please email us at plosone@plos.org. Thank you for submitting your work to PLOS ONE and supporting open access. Kind regards, PLOS ONE Editorial Office Staff on behalf of Dr. Tzen-Yuh Chiang Academic Editor PLOS ONE https://doi.org/10.1371/journal.pone.0245120.r008

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