Genetic Variability of Alnus cordata (Loisel.) Duby Populations and Introgressive Hybridization with A. glutinosa (L.) Gaertn. in Southern Italy: Implication for Conservation and Management of Genetic Resources

Round 1

Reviewer 1 Report

The topic of the paper is very actual and presented results can help to protect endangered populations of Mediterranean trees in the face of climate change and at the same time is the starting point for future research rising many key questions.

Major commnets

1. I recommend rearangment of Introduction:

• Start with more interesting information in the first paragraph, I suggest the role of hybridization and its threats for Alnus cordata populations and the importance of study for conservation, etc. (as mentioned on lines 58-66).

• Information about other threats for A. cordata should be mentioned in Introduction and also about its importance, e.g in the face of ongoing climate change thanks to its drought tolerance (e.g. Innangi et al. 2017, Forests) in order to stress the importance of study topic.

• Modern more recent phylogeography studies are missing; e.g. Havrdová et al. 2015, Molecular Ecology; Mandák et al. 2016, New Phytologist

2. Materials and methods

• Add some charactersitics about large allele dropout, null alleles or scoring errors and genotyping error rate to show that used SSR markers were well chosen.
• Explain the gap between sampled populations (only 1, CAM) between ORS (in the north) and FOR (in the south).

3. Results: There are so many analyses (Structure, PCoA, AMOVA, UPGMA) which provided similar results. So, consider rearrangement of some of these results to Supplement.

Minor comments

• line 57: The hybridization
• Fig. 1: shapes with different colours would be more clear to get a  grasp of sampling design; A. glutinosa and A. cordata distribution ranges would nicely supplement this Figure
• line 84: Explanation why the same number of trees was not sampled on each site would be great.
• line 108: According to reference 32, markers were developed for A. maritima, not A. glutinosa, please clarify.
• Fig. 3: change species name to italic type
• line 258: reformulate, A. cordata coexist with A. glutinosa not with its area
• line 262: SSRs

Author Response

Reviewer #1

Introduction

Q1:  Start with more interesting information in the first paragraph, I suggest the role of hybridization and its threats for Alnus cordata populations and the importance of study for conservation, etc. (as mentioned on lines 58-66).

Answer: Line  30   We have reorganized the introduction as the reviewer indications. The first paragraph starts with the “ role of hybridation “

Q2: Information about other threats for A. cordata should be mentioned in Introduction and also about its importance, e.g in the face of ongoing climate change thanks to its drought tolerance (e.g. Innangi et al. 2017, Forests) in order to stress the importance of study topic.

Answer: Line 53 -58 and line 71 we have mentioned other threats for A. Cordata its tolerance to drought stress also adding the reference indicated by the reviewer

Q3: Modern more recent phylogeography studies are missing; e.g. Havrdová et al. 2015, Molecular Ecology; Mandák et al. 2016, New Phytologist

Answer: Line 40-44   we have included  the more recent studies

 

Materials and methods

Q 4: Add some charactersitics about large allele dropout, null alleles or scoring errors and genotyping error rate to show that used SSR markers were well chosen.

Answer Line 133-139  we have included some characteristics of the markers choosen as the PI probability of identity and the presence of null alleles

Q5: Explain the gap between sampled populations (only 1, CAM) between ORS (in the north) and FOR (in the south).

Answer line 86-92  we gave more details on the sampling site, the sampling was conducted according with the populations census by the Regional Forestry Agency

Q 6 : Results: There are so many analyses (Structure, PCoA, AMOVA, UPGMA) which provided similar results. So, consider rearrangement of some of these results to Supplement.

Answer : We rearranged the Results section : we moved Table 2 , Table 6 and Table 7 to supplementary materials

Minor comments

Q7:  line 57: The hybridization

Answer : Line 30 we have corrected

Q8: Fig. 1: shapes with different colours would be more clear to get a  gap of sampling design; A. glutinosa and A. cordata distribution ranges would nicely supplement this Figure

Answer : We have included the distribution range in the figure

Q8: line 84: Explanation why the same number of trees was not sampled on each site would be great.

Answer line 90-93 we explained that the number of trees collected depends on the size of the sites

Q9: line 108: According to reference 32, markers were developed for A. maritima, not A. glutinosa, please clarify.

Answer line 120 we corrected the markers used were developped in A. glutinosa and A. maritima

Q10: Fig. 3: change species name to italic type

Answer we have changed the names in the figure

Q11: line 258: reformulate, A. cordata coexist with A. glutinosa not with its area

Answer:  Line 272-273 We reformulate the sentence

Q12:line 262: SSRs

Answer: line 279 we reformulate the sentence

Reviewer 2 Report

Dear authors,

I have read your manuscript with great interest. In general, I like the manuscript. Overall, the manuscript is basically written clearly, and materials and methods used for data analysis are acceptable. The results are clearly presented, and the discussion is reasonable and sound. However, list of references should be updated. Please include more recent published papers for natural hybridization and introgression between alder species. Additional corrections to minor errors and text editing, and few comments and suggestions are marked in the attached document.

Kind regards

Comments for author File: Comments.pdf

Author Response

Reviewer #2

Q1: Please include more recent published papers for natural hybridization and introgression between alder species.

Answer:  we included more recent pubblished papers as suggested the Reviewer

Q2: Additional corrections to minor errors and text editing, and few comments and suggestions are marked in the attached document

 We are made all the corrections indicated in the pdf