Genetic Transformation of Forest Trees and Its Research Advances in Stress Tolerance
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors1. Some sections need re-organization as they have not been presented systematically.
2. Authors should explain the constraints and challenges of tree genetic transformation in detail and how they have been overcome, citing relevant studies.
3. Studies on tree genetic transformation should be elaborated in the corresponding sections.
4. Authors have detailed out recent techniques for transformation, but have they been used for trees? If not then this section can be shortened and provided in a tabular/graphical way if possible.
5. Overall, authors need to delve more into the challenges, prospects and successes of tree transformation, which is still lacking in this review.
Comments on the Quality of English LanguageEnglish is satisfactory, with few modifications required.
Author Response
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Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe paper is a fairly up-to-date compilation of advances in the genetic modification of trees, specifically transgenesis. In my opinion, it is not necessary to report the transformation methods since it is a journal for an expert audience. On the other hand, the differences between transgenic, cisgenic and edited trees should be explained. Editing does not always lead to the generation of a transgenic tree. I recommend making some reference to the biosafety of modified trees and advances in this area. I do not agree that transgenesis is the only way to improve trees, and this should be reflected in the paper.
Author Response
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Reviewer 3 Report
Comments and Suggestions for AuthorsThe manuscript present interesting, comprehensive and well written overview on the state of the art of genetic transformation and modification of trees. The subject of the manuscript is very actual and interesting to a broader spectrum of readers, not only those working in forestry. The review covers recent literature and advances in the field.
Minor issues: English should be checked, minor spelling and grammar errors corrected, e.g. - Line 50 - We systemically summaries – we systematically summarize
In section 2 add a brief explanation of what do you mean by the term “transformation receptors” (one or two sentences)
In section 2.1. add a brief explanation on how the agrobacterium-transformation method is performed, what is the principle of this method
Lines 325-326 – there is no need to write enzyme names in capital letters
Comments on the Quality of English Language
Minor editing of English is required, in general the English is of good quality.
Author Response
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Reviewer 4 Report
Comments and Suggestions for AuthorsThe authors have tried to write a review about forest trees genetic transformation without addressing the main problems of this technology to this particular group of plants.
It seems that they don't have real experience on tree transformation and just gathered information from different places without making a deep analysis of their real meaning to the field and maybe without really understanding the limits of many of them. A review is much more than a juxtaposition of paragraphs from research papers.
When the authors talk about some achievements they should inform the reader not only that A and B transformed cotyledons of the species C with that gene. They should tell if they achieved transgenic plant regeneration, if the transgene effect was measured in vitro, in the greenhouse or in the field. When they provide examples of rice or arabidopsis (clearly not belonging to forest trees) they should discuss how these studies could be applied to trees.
Starting from the basic:
Instead of using target tissues, target cells or target explants, they use the term "transformation receptor". In Biology, the term receptor refers to molecules that receive signals by binding to other molecules called messengers, and then send a specific signal onward. If the authors want to use that name for the target explant they should explain thoroughly their reasons.
Other example of confusion is Table 1. They provide a column called “transformation technique” in which they just write a list of plasmids. So, I assume that the technique was Agrobacterium-mediated transformation, although it could be plasmid bombardment too.
There is a lack of coherence throughout the manuscript. When the authors enumerate the possible "transformation receptors" they make a list on the text, that is not consistent with what they use in Figure 1 (Figure 1 is not referred to in the text, by the way).
If we focus on figure 1, they talk about leaves, stems, hypocotyls, roots, somatic embryos, but then fail to explain how these explants are going to originate a transgenic organism. Transgenic cells belonging to all these tissues need to proliferate and regenerate the rest of cells of the plant. Apart from somatic embryos, which can do it by secondary embryogenesis, the rest of explants need to form adventitious shoots or a callus that eventually can regenerate embryos or shoots, but these esential processes are not mentioned in the paper.
Also, they talk about new techniques that require a protoplast regeneration system, but they don't mention it, or how to get and regenerate protoplasts from tree cells. In fact, the word "protoplast" is mentioned only once, when they talk about the possibility of using pine cotyledons for transient expression of the GUS gene, that is quite an irrelevant example in this context.
The authors don’t explain well the new techniques they present. They give some rough outlines followed by a series of examples of the use in non woody plants, without considering the feasibility of applying them to forest trees.
Other problems of the manuscript: planting transformed trees in the field is restricted to a short list of countries, due to the special risks of transgenic deployment in natural areas. The authors don’t treat this issue at all, only say vague things about safety.
Another example of this paper being almost a draft is this sentence related to Table 2: “We summarized the genes that have responded to abiotic stress in model plants and crop species in recent years, so as to provide inspiration for tree research (Table 2)”, but they don’t discuss anything more about these genes or the real results.
In the case of biotic stresses, why not to cite important research as the one carried out on American chestnut?
Finally, the language is redundant and full of sentences that repeat the same of the previous one just changing the order of the words. It looks like a draft in which they have started to collect information and write some ideas in different ways before they decide which is the best sentence, no like a finished paper to be published in a good journal.
Comments on the Quality of English LanguageLanguage needs to be revised: there are many redundant words and sentences poorly constructed, as well as mistakes (use of systemically for systematically, for example).
Author Response
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