Genetic Monitoring of Alnus glutinosa Natural Populations Using Two Generation Cohorts

Round 1

Reviewer 1 Report

1) The juvenile populations were likely affected by the management practices in their genetic diversity, however, the paper did not present any information on what management practices were applied; 

2) The authors used the cambium samples of mature trees and leaf samples of young seedlings for DNA extraction, what is the reason for not using leaf samples for mature trees, and were there any difference in DNA extraction or DNA quality  between the two types of samples;

3)  The text needs to be more structured for easier reading and understanding;

Author Response

Dear Reviewer,

 

Thank you for your valuable comments. We have made adjustments based on your comments and suggestions. Your comments helped us to improve the manuscript. The detailed comments by bullet points can be found bellow:

 

Comments and Suggestions for Authors

1. The juvenile populations were likely affected by the management practices in their genetic diversity, however, the paper did not present any information on what management practices were applied; 
   • The management practices to promote natural regeneration are explained in the paper. The introduced explanation is as follows: “The management for natural regeneration promotion involved selective logging, creating narrow strips (approx. 30 m wide) of well-lit and scarified soil for easier regeneration of target species. Selective logging was performed during mast years for black alder.” Lines 99-102.
2. The authors used the cambium samples of mature trees and leaf samples of young seedlings for DNA extraction, what is the reason for not using leaf samples for mature trees, and were there any difference in DNA extraction or DNA quality  between the two types of samples;
   • The reason for cambium sampling for mature trees supplied in lines 108-109 (clean manuscript – lines 106-108) and is as follows: “The cambium samples for mature trees were collected, as sampling of leaves was difficult due to the tree height.”
3. The text needs to be more structured for easier reading and understanding;
   • For easier understanding, subsections in the result part of the manuscript were introduced. Lines 157 (clean manuscript line 156), 179 (clean manuscript line 177) and 245 (clean manuscript line 220).

 

Submission Date

13 January 2023

Date of this review

25 Jan 2023 20:37:22

Reviewer 2 Report

Alnus glutinosa is an important forest tree species in Europe with flooding tolerance. Research on the dynamic genetic diversity among population favors its cultivation management and resources protection. The work represents a new, original, and interesting contribution. The structure and organization of the paper appear to be sound in general, but some aspects should be clarified and/or more thoroughly explained and justified (see below). Introduction section It was suggested that study on the factor causing unevenly geographic distribution of Alnus glutinosa in the Lithuania is briefly introduced in the section. Materials and methods section Which forest stand type does the sampled Alnus glutinosa population belong to? Is it pure or mixed forest? Line71-72 Do “the rest are State Forest Genetic Reserves” mean that the rest are not seed stands? And which propagation type is used? Results section Line 227 Change “Figure 3” to “Figure 4”. Discussion section Line 233 Why is the pattern of population differentiation formed?

Author Response

Dear Reviewer,

Thank you for your valuable comments. We have made adjustments based on your comments and suggestions. Your comments helped us to improve the manuscript. The detailed comments by bullet points can be found bellow:

Comments and Suggestions for Authors

Alnus glutinosa is an important forest tree species in Europe with flooding tolerance. Research on the dynamic genetic diversity among population favors its cultivation management and resources protection. The work represents a new, original, and interesting contribution. The structure and organization of the paper appear to be sound in general, but some aspects should be clarified and/or more thoroughly explained and justified (see below).

Introduction section It was suggested that study on the factor causing unevenly geographic distribution of Alnus glutinosa in the Lithuania is briefly introduced in the section.

• A. glutinosa distribution description was supplemented with an explanation of the majority of the species stands are found in first provenance region (line 57-58).

Materials and methods section Which forest stand type does the sampled Alnus glutinosa population belong to? Is it pure or mixed forest?

• Most of the investigated stands are pure alder stands. They are naturally regenerated mature stands. We have added the explanation to the manuscript text (lines 72-73), and also we inserted a column with stand species composition to Table 1.

Line71-72 Do “the rest are State Forest Genetic Reserves” mean that the rest are not seed stands? And which propagation type is used?

• The seed stand in this case is a special type of GCU. These GCUs serve as seed source for gathering seeds for artificial forest regeneration and seedling production for black alder in Lithuania. State Forest Genetic Reserve is a reserve, where the target plant species (in this case A.  glutinosa) is preserved. The explanation introduced to the text lines 74-76 (clean manuscript lines 73-75).

Results section Line 227 Change “Figure 3” to “Figure 4”.

• corrected

Discussion section Line 233 Why is the pattern of population differentiation formed?

• The more thorough introduction to the theory given in the manuscript. Population differentiation is usually lower at the central distribution range, where the growth conditions for the species is at optimal and where species density is expected to be high [48].” Lines 280-282 (clean manuscript lines 255-257).

Submission Date

13 January 2023

Date of this review

Reviewer 3 Report

The manuscript “Genetic monitoring of Alnus glutinosa natural populations using two generation cohorts”  aimed to assess genetic diversity of autochthonous protected A. glutinosa populations, to compare the genetic diversity between maternal and progeny generations, in a distribution area that is known to harbour extensive genetic diversity, and to assess if there is an impact on genetic diversity when forest management practices to promote natural regeneration of mature stands are introduced.The manuscript is prepared professionally. It includes a well-crafted abstract and an exhaustive introduction that justifies the research undertaken. The introduction points to the deficiencies in the literature on the subject. The aim is clearly defined. Modern analytical methods were used in the research. The discussion of the results is well prepared. The conclusions are well-defined. The illustrative material is appropriate.

 

In my opinion, the manuscript after corrections, will be suitable for publication in a journal.

 

Detailed comments:

Abstract: Should be include some results obtained from study. For example number of alleles, Ho, He etc.

What authors mean autochthonous????

Introduction - The introduction is enough in my opinion. Below minor points should be corrected

Please follow the reference number from 1 to.....I mean start with [1]...

The current unprecedented climate change will affect terrestrial ecosystems more 30 significantly than any other biome [1,2,3];

Please add below references

Fidan, C.; Esen, D.; Demirsu, N.; Cabak, E.; Guner, S. Effects of site preparation and postplanting cultural treatments on the establishment and early growth of maritime pine (Pinus pinaster Ait.). Turk J Agric For. 2022,  46 (5):613-622.

Ozer, G.; Makineci, E. Fruit characteristics, defoliation, forest floor and soil properties of sweet chestnut (Castanea sativa Mill.) forests in İstanbul-Turkey. Turk J Agric For. 2022, 46 (5): 703-716.

Table 1

Table 1. Wild natural A. glutinosa populations sampled for this study

What is mean wild natural?????

Please give coordinates with international standards degree etc. 

Table 2. Please give average allele number etc. on table

Please give references for used 20 SSR markers on Table 2

Figure 2 is not clear please make it more clearer

Figure 3 K values are missing

Author Response

Dear Reviewer,

Thank you for your valuable comments. We have made adjustments based on your comments and suggestions. Your comments helped us to improve the manuscript. The detailed comments by bullet points can be found bellow:

Comments and Suggestions for Authors

The manuscript “Genetic monitoring of Alnus glutinosa natural populations using two generation cohorts”  aimed to assess genetic diversity of autochthonous protected A. glutinosa populations, to compare the genetic diversity between maternal and progeny generations, in a distribution area that is known to harbour extensive genetic diversity, and to assess if there is an impact on genetic diversity when forest management practices to promote natural regeneration of mature stands are introduced.The manuscript is prepared professionally. It includes a well-crafted abstract and an exhaustive introduction that justifies the research undertaken. The introduction points to the deficiencies in the literature on the subject. The aim is clearly defined. Modern analytical methods were used in the research. The discussion of the results is well prepared. The conclusions are well-defined. The illustrative material is appropriate.

 

In my opinion, the manuscript after corrections, will be suitable for publication in a journal.

 

Detailed comments:

Abstract: Should be include some results obtained from study. For example number of alleles, Ho, He etc.

• Abstract was supplemented with average diversity measures for glutinosa populations (Ar, Ho and He) (line 22)

What authors mean autochthonous????

• By the term autochthonous we mean that glutinosa is a native tree species for Lithuania, as opposed to introduced by humans. It grows there from the last ice age. The text was supplemented with the explanation “which is assigned to first provenance region (Figure 1).” Lines 57-58.

Introduction - The introduction is enough in my opinion. Below minor points should be corrected.

Please follow the reference number from 1 to.....I mean start with [1]...

• The citation order corrected.

The current unprecedented climate change will affect terrestrial ecosystems more 30 significantly than any other biome [1,2,3]; Please add below references

Fidan, C.; Esen, D.; Demirsu, N.; Cabak, E.; Guner, S. Effects of site preparation and postplanting cultural treatments on the establishment and early growth of maritime pine (Pinus pinaster Ait.). Turk J Agric For. 2022,  46 (5):613-622.

• This particular study deals with various soil preparation techniques for maritime pine. In our study we have investigated naturally formed stands of glutinosa from different climate zone. We feel that this particular publication has no relevance to our research.

Ozer, G.; Makineci, E. Fruit characteristics, defoliation, forest floor and soil properties of sweet chestnut (Castanea sativa Mill.) forests in İstanbul-Turkey. Turk J Agric For. 2022, 46 (5): 703-716.

• The paper recommended for citation deals with sweet chestnut and the impact of soil properties on the yield in sweet chestnut stands. Our study haven’t analyzed the yield or soil properties of glutinosa populations. We fail to see why this particular study of sweet chestnut should be cited.

Table 1

Table 1. Wild natural A. glutinosa populations sampled for this study

What is mean wild natural?????

• The object of this study were naturally regenerated and unmanaged (the only management in five GCUs, were done recently to promote natural regeneration) conservation areas of glutinosa. Table 1 legend was changed to: “A. glutinosa GCUs sampled for this study”

 

Please give coordinates with international standards degree etc. 

• The coordinates from WGS84 converted to degrees minutes and seconds.

Table 2. Please give average allele number etc. on table

The average number of alleles, effective number of alleles, observed heterozygosity, expected heterozygosity and inbreeding coefficient added to the table.

Please give references for used 20 SSR markers on Table 2

• Primer source references provided.

Figure 2 is not clear please make it more clearer

• Figure 2 visualized better, and improved figure resubmitted.

Figure 3 K values are missing

• Figure 3 capture changed to ”Genetic structure of A. glutinosa populations as identified by STRUCTURE. Each sampled tree is identified as a vertical bar, where a color denotes the part of the genome that belongs to each of the most probable clusters (K=2)” and changes made in the text line 257 (clean manuscript line 232).

 

Submission Date

13 January 2023

Date of this review

20 Jan 2023 20:01:18

Round 2

Reviewer 1 Report

Quality of the paper is improved.

Reviewer 3 Report

The authors made all necessary changes and addition.