Genetic Diversity of Oxytropis Species from the Center of the Genus Origin: Insight from Molecular Studies

Round 1

Reviewer 1 Report

Based on cpDNA sequences, the present study reveas the pattern of the genetic diversity and complex phylogenetic relationships of Oxytropis species in Southern Siberia. The paper is originality, good quality of presentation and will be a high interest to the readers. All the cited references are relevant to the research. The methods are  adequately described and the results are clearly presented.

I have only one question to the paper's authors:

Is it possible to mark barcodes for your voucher specimens and where they storage? Could you place this information in the Supplementary?

Comments for author File: Comments.pdf

Author Response

Thank you very much for reviewing our manuscript and good evaluation of our study. Collecting field samples for this study followed unified procedure. Usually, 1-3 herbarium sheets from each population collected as voucher specimens and stored in herbaria collections. For the genetic analysis of populations, we separately collected samples of different plant individuals, and studied these specimens, and not those specimens that were stored in the herbarium. From this point of view, its better does not mix these samples.

We added the following sentence to the Materials and Methods: “All collected species has been approved with herbarium specimens presented in the main Russian herbaria (LE, MW, UUH) –All specimens used for DNA extraction are deposited at the Federal Scientific Centre of the East Asia Terrestrial Biodiversity, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, Russia.”

Need to be mentioned that very sparse part of herbaria in Russia have barcodes, usually just numbers of the voucher specimens. In such case basic information about the samples will be brief. Details about all samples presented in Table 1.

Reviewer 2 Report

Few minor comments are indicated below

Table 1 is too extensive spanning five pages, can be considered for splitting in to different tables.

Line 243: Many reviews of genetic variability… sentence can be revised.

Line 293-296: According to the authors, re-293 vealed relatively high levels..... sentence is unclear, can be revised.

Author Response

Thank you very much for reviewing our manuscript and constructive comments.

The size of the Table 1 reflects the amount of material studied, all information here is usually presented in a brief format. If we split the table, it would still be necessary to provide the entire list of studied species and populations in order to provide information either on genetic diversity parameters or GeneBank Accession Numbers. Also this table provides useful data for future discussion. Therefore, we ask to leave Table 1 in present form. In the final version this table will be arranged to landscape orientation. In such form it will not span many pages and fit well within the manuscript.

 

We revised all aforementioned sentences in order to have clear explanation.

Line 243: We revised this sentence:

“Studies of the genetic variability of plant species have shown that the level of genetic diversity is influenced by a number of factors, such as mating systems, life history features, chromosomal variability, population distribution, as well as ecological factors.”

 

Line 293-296: We revised this sentence:

“According to the authors, the revealed relatively high level of genetic diversity in rare Astragalus taxa is due to two main reasons: 1) aspects of seed biology (maintenance a healthy seed bank), 2) spatial climatic and soil variability shaping local adaptations.”

Reviewer 3 Report

This paper reads very well and is interesting.

I would be very interested in how the different species and haplotypes relate to ploidy levels and to the sections within the genus. Ploidy is most likely acting as a reproductive barrier. Would it be possible to explore the ploidy levels of each of the 3 groups in Figure 2. It is likely some of these subclades are allopolyploid hybridisation events and I think that this may add to the story you have.

If you still have herbage samples you could to flow cytometry to determine ploidy levels for all samples and this may add to the story (or a future paper). 

Certainly, some further discussion on ploidy should be informative.

The paper reads very well but one minor edit suggested

351 ‘All rest species’ change to ‘All the rest of the species’

Author Response

Thank you very much for reviewing our manuscript and encouraging comments. We agree that the processes of allopolyploid hybridization could contribute to the formation of subclades in the genealogical network of haplotypes. Unfortunately, we have only literature data on the ploidy of the studied species. Determining the level of ploidy of the studied populations and discussing in relation to the level of diversity and phylogenetic relationships may be a separate study in the future. Thanks for your suggestion.

Discussion on ploidy is presented in the manuscript (Lines 314-324). We add more discussion to that story.

We have modified the sentence on line 351 according to your suggestions.