Genetic Variation among Somatic Embryo Clones of Nordmann Fir Grown as Christmas Trees

Round 1

Reviewer 1 Report

Somatic embryogenesis cloning techniques for Nordmann fir is a viable option for consistent and better quality/exchange of Christmas tree production.

There has been a gap about how somatic embryo clones preform in comparison to seedlings for Christmas tree production. As I know this is the first time an article compares a large number of somatic embryo clones of Nordmann fir to seedlings and evaluate their performance as Christmas tree clones. I think this information is very relevant for the future of how to produce Christmas trees as well as how to evaluate clonal performance on different sites. The main question the growers have is if there could be a optimal clone be found and be propagated by SE-techniques? Or is still seedlings a superior plant source?

 

This study includes a high number of families and somatic embryo clones and strengthens the overall view about how Somatic clones grow in field conditions.

Regarding the controls: there are NONE comparable seedlings in the field site Holstebro, this could hamper the comparison SE vs Seedlings however there is two field sites 153 resp. 122 seedlings that I think is a fair number In comparison to the 1636 vs 1124 SE trees.

I believe the message of the article is clear and all the discussion follows the introduction and methods section. Its well written as I see it, the authors have included the most relevant references. They are mirroring the latest research int the field.

Figure 9: if the worst correlation lines between sites could be in a different color it would be easier to see the "overall picture" there is so many lines in black that its hard to follow.

 

Misspelling
Page 3, line 99 "(Figure )" should be "(Figure 1)"
Page 18, line 380, "under planted" 
PAge 15, line 279, single bracket ( 
Figure 3 page 6, line 161 "E: Needle color" says "F: Color" in figure picture.

2.1 Plant material and test sites
Its not described in the test site description that Ry was under-planted mention in the results section page 18 line 380. This could be good to mention.

 

Author Response

Please see the attachment

Author Response File: Author Response.pdf

Reviewer 2 Report

The manuscript entitled “Genetic variation among somatic embryo clones of Nordmann fir grown as Christmas trees” evaluates the performance of clones resulting from somatic embryogenesis and their comparison with zygotic seedlings and also estimates the family performance and clonal genetic parameters as genetic variance and broad sense heritability. Furthermore, it studied the clone stability measured as genotype by site and year-by-year interactions of different traits related to Christmas tree production. Altogether paper is well written and interesting research has been undertaken, however, the manuscript needs some minor revisions for its improvement. See the following comments:

1- I think the title can be written better as it doesn’t include the main theme of the performed research.

2- In the introduction, there is a missing paragraph to describe somatic embryogenesis and the possible genetic change, and the underlying genetic mechanisms.

3- However, it has been shown on a map, the exact geographical coordinates of sampling locations including latitude, altitude, and also elevation can be present in a table (maybe as supplementary material).

4- L97: It was worthwhile if the authors could add a picture of the embryogenesis process and plantlet regeneration.

5- A PCA biplot or a clustering dendrogram of the studied plant material based on the evaluated characteristics may also show a better genetic relationship.

 

Despite the above-mentioned comments, the work is worthwhile in the field of Nordmann fir (Christmas trees) production and breeding with a commercial theme. I strongly suggest the manuscript for publication in Forests after minor revision.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf