Testing the Efficiency of the Push-and-Pull Strategy during Severe Ips typographus Outbreak and Extreme Drought in Norway Spruce Stands

Round 1

Reviewer 1 Report

The authors mainly evaluated the effect of using a mixture of repellents against the bark beetle Ips topographus in Norway spruce stands. The field experiments were adequately conducted, and the authors objectively discuss some field and methodological conditions that lead to limitations of the study. My main concern is about the clarity of the text, many sentences being quite unclear. A native English speaker should check the whole manuscript.

Major comments

It would be better to replace “anti-attractant” by “repellent” throughout the text.

Title. The part “protective … effects” is a too complex wording. Another title could be: “Testing the efficiency of the push in push-pull strategy during Ips topographus outbreak and extreme drought in Norway spruce stands”.

L105. What is the meaning of “but” in this sentence? I don’t understand the contrast that this word implies.

L108. I don’t see your point 3) as a third subtopic, but rather as referring to your discussion and/or conclusions.

Page 5. The first four paragraphs are short, and their contents are partly redundant and/or misplaced. Please, rephrase all this, one topic after another.

Page 5, paragraph 5, L187-190. These sentences do not belong to M&M but should go to Discussion. And replace “suggested” by “implied”.

Page 5, paragraph 6. Nearly all sentences mention, thus should go to, Results.

L233. Replace “growth” by “increase”.

L248-249. Statistical differences are not shown in Fig. 3 so that the reader remains doubtful. Moreover, if I got you right, you say about this Fig. 3 (in Discussion) that there is no difference. By the way, note that in this paragraph you use “dead” and “infested” trees as if both symptoms would be identical.

Page 8, Figure 4. You show means, why not also SD values?

Discussion. Paragraphs and/or text parts are unclear. Three examples: 1) L339-344 is confusing because if there is no statistical difference, you then can’t evoke a visible trend that should be confirmed in the future, etc. Instead, you could simply tell us that, because there is no difference, it’s ok to only use the most convenient variant. 2) The whole paragraph under Part 4.2. and especially its sentence L349-351 are confusing. 3) Paragraph L383-385 is strange.

Minor comments

L27. Trunk.

L30-31. Rephrase sentence.

L33-34. Rephrase sentence, by using another verb than “argue” because the sentence content is already convincing.

L35. Replace “high” by “dense”.

L42. “I.” by “Ips”.

L50. “Ips” by “I.”, and delete (L.)”.

L54. Rephrase “excessive number”.

L58. “The repelling effect (push) on trees is combined…”.

L61. Replace “generated” by “metabolized”. What is meant by “or”? Are both pathways known to occur?

L70. “single-sensillum” of an antenna?

L91. Rephrase “beetle… decrease”.

L92, L97, and throughout the text. Is it ok for the journal to start a sentence with a reference number?

L117 and later. Replace the circa sign by “ca.’, or by nothing, since the rounded values already suggest an approximation, and anyhow, elevation values gathered e.g. by GPS are always approximative.

L124. Rephrase “area of extant” which is unclear to me.

L274-275. Change end of sentence to get: “… traps was [not were!] found in both variants (corr. … variant B; Fig. 5).”.

Table 3. I guess the journal doesn’t accept text in red.

L304-305. Rephrase this sentence that contains four times “experiment”.

L315. Replace “indisputable ultimate” by “unequivocal”.

L317-320. Rephrase this unclear and too long sentence.

L322. Treated.

References 46, 50, 61. Replace “Contorta” by “contorta” and set genus and species names in italic.

Author Response

We would like to thank Reviewer 1 for the valuable comments. We have accepted the majority of the Reviewer 1 comments and suggestions. We have corrected the related text.

We would prefer to keep the original text and structure in the following points:

1) Reviewer 1 comment: “It would be better to replace “anti-attractant” by “repellent” throughout the text.”

Our response: We see “anti-attractant” as a more precise and focused term than “repellent”. An established term of similar structure is “antifeedant”. “Repellent” proper for insects has a specific meaning of ‘insect moving away from source’ (Dethier et al. 1960). See a small review by Månsson (2005), his Fig 3. The term “anti-attractant” is used in previous papers  (Jakuš & Dudová 1999; Jakuš et al. 2003; Erbilgin et al. 2007; Andersson et al. 2011; Jakuš et al. 2011;Schlyter 2012). We would prefer a continuity in terminology.

Valuing the opinion of Reviewer 1, we note that the use of “Repellent” in a less proper way is common. We propose a middle way:  Using “Repellent” as a Keyword and once in the Introduction, explaining our use of a more exact term, this would help the readers’ understanding.

Andersson MN, Binyameen M, Schlyter F. 2011. Attraction modulated by spacing of pheromone components and anti-attractants in a bark beetle and a moth: A smaller scale of action in the moth. J Chem Ecol 37: 899-911  10.1007/s10886-011-9995-3

Dethier VG, Browne LB, Smith CN. 1960. The designation of chemicals in terms of the responses they elicit from insects. Journal of Economic Entomology 53: 134-136 

Erbilgin N, Gillette N, Mori S, Stein J, Owen D, Wood D. 2007. Acetophenone as an anti-attractant for the western pine beetle, Dendroctonus brevicomis LeConte (Coleoptera: Scolytidae). J Chem Ecol 33: 817  10.1007/s10886-007-9267-4

Jakuš R, Blaženec M, Vojtěch O. 2011. Use of anti-attractants in specific conditions of protected areas. Folia Oecologica, 38 (1), 46–51.

Jakuš R, Dudová A. 1999. Pokusné použitie agregačných a antiagregačných feromónov proti lykožrútovi smrekovému (Ips typographus) v rozpadávajúcich sa smrekových porastoch so zníženým zakmenením. Journal of Forest Science 45: 525-532.

Jakuš R, Schlyter F, Zhang Q-H, Blazenec M, Vavercák R, Grodzki W, Brutovský D, Lajzová E, Bengtsson M, Blum Z, Turcáni M, Gregoiré J-C. 2003. Overview of development of anti-attractant based technology for spruce protection against Ips typographus: from past failures to future success. Journal of Pest Science (Anzeiger für Schädlingskunde = Journal of pest science) 76: 89-99  10.1046/j.1439-0280.2003.03020.x

Månsson PE. 2005. Host selection and antifeedants in Hylobius abietis pine weevils https://pub.epsilon.slu.se/759/, Acta Universitatis agriculturae Sueciae, 1652-6880 ; 2005:16

ISBN 91-576-7015-3

Schlyter F. 2012. Semiochemical diversity in practise: Anti-attractant semiochemicals reduces bark beetle attacks on standing trees -a first meta-analysis Psyche: A Journal of Entomology 2012: Article ID 268621  10.1155/2012/268621

2) Reviewer 1 comment:  “L108. I don’t see your point 3) as a third subtopic, but rather as referring to your discussion and/or conclusions.”

Our response: We rather consider “point 3” as key subtopic. The evaluation of efficiency of tree protection measures was the main reason for conducting the experiment.

3) Reviewer 1 comment: “Page 5, paragraph 6. Nearly all sentences mention, thus should go to, Results.”

Our response: We consider the related text important for understanding of used methods. Moving the text to Results would negatively affect the consistency and understandability of the paper.

We also have response to reviewer comments: “L61. …..What is meant by “or”? Both pathways known to occur?

Our response: Yes, both pathways occur

Ramakrishnan R, Hradecký J, Roy A et al, (2022) Metabolomics and transcriptomics of pheromone biosynthesis in an aggressive forest pest Ips typographus. Insect Biochem Molec 140:103680.

Vanĕk T, Halík J, Vanková R, Valterová I (2005) Formation of trans-verbenol and verbenone from α-pinene catalysed by immobilised Picea abies cells. Biosci Biotechnol Biochem 69:321–325.

Reviewer 2 Report

Review report 

In general, This study is very interesting and has a scientific topic with a great impact on the field. 

Detailed comments:

1-The English language and /writing style is fine needs some minor check spelling and grammar check

2-Please avoid using the personal pronouns (I, We, our) such as in line 19 we tested, line 27 our data suggested.

Abstract

_This section is missing the direct aim of the study. Please state the aim of the study clearly in this section.

Keywords:

-The keywords has been chosen very carefully and accurately . Please add the word drought to the keyword list.

Introduction

-The introduction is ok.

Materials and Methods

-This section is ok and the methods are adequate.

 Results:

The results are very interesting and well presented but some data needs a better discussion. 

Discussion:

_This section is ok but it can be improved 

Data in Table 3 and Figure 5 needs to be clearly discussed 

The author is advised to combine the Results and Discussion in one section for better explanation and understanding to the  provided data.

Conclusion :

This section is well written and the conclusion is supported by the results of this study and includes the most important findings.

References

This section is well written. And it is up To date . 

Author Response

We would like to thank Reviewer 2  for valuable comments. We have accepted almost all of the Reviewer 2 comments and suggestions and we have corrected related text.

We would prefer to keep „results“ and „discussions“ as separate chapters. We note that the paper is not very short and we consider the standard separation of  „results“ and „discussions“ more suitable for the readers’ understanding of our work.