Evaluation of Artemisia absinthium L. Essential Oil as a Potential Novel Prophylactic against the Asian Citrus Psyllid Diaphorina citri Kuwayama

Round 1

Reviewer 1 Report

 

The selected topic of this manuscript is very interesting and deserves attention. The results represent a significant contribution to the science. The text is written in an understandable English language.

References are adequately cited and the authors made a good selection of publications to include in this research.

The authors conducted a comprehensive experiment and obtained good results. Therefore, my suggestions will go in the direction of minor changes.

Please find below some specific comments.

Abstract: If we talk about pest treatment we can not say toxicity. Effects caused by insecticide on the pest insect species can only be called efficacy against some insects. The same is given in the introduction.

I would rather call it the fumigant mode of action than the fumigant toxicity.

Toxicity is something that should be applied only when we talk about mammals, humans, and non-target species.

Word Essential should be given in small letters.

Table 1: It would be easier to follow if the compound name would be in the first column.  It is a matter of esthetics and it is more practical.

Please correct- 8 male and eight female to – eight male and eight female

The authors said- Then the seedlings were again confined with gauze nets and placed under laboratory condition, and the number of hatched nymphs were counted until all the eggs were hatched.

However, if the treatment has ovicidal effects then authors could wait forever to have all eggs hatched. Did you mean on all eggs in control? How did you know that no more eggs are going to hatch in treatment?

 

Please correct this sentence - All the conditions were like the ovicidal toxicity bioassay, to – The laboratory conditions were equal to those during the ovicidal toxicity bioassay ... or similar.   

Please decrease the font of formulas in “Statistical analysis”

 

Please change Psidium guajava to italic

 

One space is redundant between the number and percentage -  80 % reduction in honeydew droplets secretion by D. citri at 0.1 μg/mL

 

In Figure 2 it is not very clear what should be seen in the upper part of the photo. Please provide a sharper photo or give more explanation about the differences between the presented parts of the photo.

 Table 2: In Table 2 the parameters LC50, Slope, X² (d.f.), and p-value should be given in the text or in the title of the figure but not like it is now. It is not clear in this format.  

In fact, the whole of Table 2 could be given as a text.

 Figure 3. This graph is not clear. Maybe the authors presented the mortality because mortality can go up and down but the survival of the population always decreases with time. Please explain this.

I understand the graph but it is not adequate to call it survival because there are also included freshly emerged individuals (those that start from zero). Is that correct? Generally speaking, when we analyze survival, it starts from 1 and drops with time. Your graph is showing that survival can go up and down, which is not the case.

 Page 12: Why is there a citation? [15]

Page 12: Please delete the wide space between these lines

 a Total number of bees treated.

b 50 % lethal dose.

d 90% lethal dose.

 Why is this Piper aduncum underlined in the discussion?

 

 

Only minor changes are needed. 

Author Response

Reviewer 1. The selected topic of this manuscript is very interesting and deserves attention. The results represent a significant contribution to the science. The text is written in an understandable English language. References are adequately cited and the authors made a good selection of publications to include in this research. The authors conducted a comprehensive experiment and obtained good results. Therefore, my suggestions will go in the direction of minor changes.

 

 

Please find below some specific comments.

Abstract: If we talk about pest treatment we can not say toxicity. Effects caused by insecticide on the pest insect species can only be called efficacy against some insects. The same is given in the introduction.

I would rather call it the fumigant mode of action than the fumigant toxicity.

Toxicity is something that should be applied only when we talk about mammals, humans, and non-target species.

 

Reply to Reviewer:

We are thankful to you for your response and suggestions. We agree to the reviewer suggestion. In the abstract and introduction, the mentioned suggestions have been incorporated.

               

The

Word Essential should be given in small letters.

 

Reply to Reviewer: The word Essential is now given in small letter

 

Table 1: It would be easier to follow if the compound name would be in the first column.  It is a matter of esthetics and it is more practical.

Please correct- 8 male and eight female to – eight male and eight female

 

Reply to Reviewer: The table has been revised according to the suggessation and 8 male and eight female is corrected.

 

The authors said- Then the seedlings were again confined with gauze nets and placed under laboratory condition, and the number of hatched nymphs were counted until all the eggs were hatched.

However, if the treatment has ovicidal effects then authors could wait forever to have all eggs hatched. Did you mean on all eggs in control? How did you know that no more eggs are going to hatch in treatment?

 

Reply to Reviewer: Sorry for this confusin in writing. We agreed to the reviewer and changes have been made. We give proper time to all the laid eggs to hatched as comapred to the control.

 

Please correct this sentence - All the conditions were like the ovicidal toxicity bioassay, to – The laboratory conditions were equal to those during the ovicidal toxicity bioassay ... or similar.   

Please decrease the font of formulas in “Statistical analysis”

 

Please change Psidium guajava to italic

One space is redundant between the number and percentage -  80 % reduction in honeydew droplets secretion by D. citri at 0.1 μg/mL

 

 

Reply to Reviewer:  The mentioned font size is now adopted, and Psidium guajava is now italic font. The redundant space is now resolved.

 

In Figure 2 it is not very clear what should be seen in the upper part of the photo. Please provide a sharper photo or give more explanation about the differences between the presented parts of the photo.

 Table 2: In Table 2 the parameters LC50, Slope, X² (d.f.), and p-value should be given in the text or in the title of the figure but not like it is now. It is not clear in this format.  

In fact, the whole of Table 2 could be given as a text.

 Figure 3. This graph is not clear. Maybe the authors presented mortality because mortality can go up and down but the survival of the population always decreases with time. Please explain this.

I understand the graph but it is not adequate to call it survival because there are also included freshly emerged individuals (those that start from zero). Is that correct? Generally speaking, when we analyze survival, it starts from 1 and drops with time. Your graph is showing that survival can go up and down, which is not the case.

 

Reply to Reviewer:  Thanks for the important question, this graph represents the survival rate of immature and mature stages of D. citri between ABEO treated and untreated sweet orange seedlings, not mortality. Yes, Survival analyses the start from 1 that decrease with time. Our graph showing the age stage survival rate (days) of four different stages of D. citri e.g., egg nymph male and female.

 

 

Reply to Reviewer:  The Figure 2 is explained in more details and pictures quality is improved now.

The table 2 is now given in the text form.

Page 12: Why is there a citation? [15]

Page 12: Please delete the wide space between these lines.

 a Total number of bees treated.

b 50 % lethal dose.

d 90% lethal dose.

 Why is this Piper aduncum underlined in the discussion?

Reply to Reviewer:  Citation is removed now. The extra spaces is now removed. Piper aduncum underlined issue is now corrected.

 

 

Reviewer 2 Report

This paper describes the effect of Artemisia absinthium essential oil (ABEO) on Asian citrus psyllid. A similar work using the combination of ABEO and Asian citrus psyllid has been reported by a research group including the same first author (Rizvi et al. 2018 ICP). It is difficult to find differences between the current study and the previous one.

There are minor typographical errors throughout the manuscript.

Author Response

Reviewer 2.

This paper describes the effect of Artemisia absinthium essential oil (AAEO) on Asian citrus psyllid. A similar work using the combination of AAEO and Asian citrus psyllid has been reported by a research group including the same first author (Rizvi et al. 2018 ICP). It is difficult to find differences between the current study and the previous one.

 

Reply to Reviewer:  

We are thankful to you for your response and suggestions. Yes, we agree to the reviewer that a similar paper with the same authorship published with title “Toxicity and enzyme inhibition activities of the essential oil and dominant constituents derived from Artemisia absinthium L. against adult Asian citrus psyllid Diaphorina citri Kuwayama (Hemiptera: Psyllidae)”. In this paper, we mainly investigate the toxicity of essential oil and its constituents and their mechanism of toxicity. However, the current paper discussed the behavioral effect of essential oil, repellent activity, antifeedant activity and the effect of Essential oil on the life table of the psyllid. If we compare both papers, there is a vast difference one is about toxicity and the mechanism of toxicity and one is about antifeedant activity and the effect of Essential oil on the life table of the psyllid.

 

Reviewer 3 Report

1.     In the abstract, “Notably…against D. citri.” is a discussion of the experimental results, which is not suitable for inclusion in the abstract. Please describe it in the discussion section.

2.     Introduction Part “12” in “Eight to 12 insecticide applications are common used in one cropping season in China, Florida, Brazil, Mexico and other major citrus-growing countries worldwide [9].” is converted into English.

3.     In the introduction section “Furthermore, the effect of Essential oil on the fitness of D. citri was also assessed using two-sex life table tools.”, the initials “Essential” are lowercase.

4.     All the titles in the manuscript need to be unified in the description of Diaphorina citri, and the name of the plant cannot be abbreviated.

5.     The abbreviations of insects and plants in the manuscript should be unified

6.     2.3 Part Settling behavior of D. citri experiment select guava methanol extract as a positive control is meaningful, the experiment also found that the repellent activity of guava methanol extract was not significant. Whether there are other commonly used positive controls for the behavioral test of D.citri.

The language of the article needs to be improved, and the presentation and logic are not smooth enough.

Author Response

Reviewer 3.

 

1. In the abstract, “Notably…against D. citri.” is a discussion of the experimental results, which is not suitable for inclusion in the abstract. Please describe it in the discussion section.
2. Introduction Part “12” in “Eight to 12 insecticide applications are common used in one cropping season in China, Florida, Brazil, Mexico and other major citrus-growing countries worldwide [9].” is converted into English.
3. In the introduction section “Furthermore, the effect of Essential oil on the fitness of D. citriwas also assessed using two-sex life table tools.”, the initials “Essential” are lowercase.
4. All the titles in the manuscript need to be unified in the description of Diaphorina citri, and the name of the plant cannot be abbreviated.
5. The abbreviations of insects and plants in the manuscript should be unified
6. 2.3 Part Settling behavior of D. citriexperiment select guava methanol extract as a positive control is meaningful, the experiment also found that the repellent activity of guava methanol extract was not significant. Whether there are other commonly used positive controls for the behavioral test of D.citri

 

Reply to Reviewer:  

We are thankful to you for your response and suggestions. All the raised correction and suggestions have been improved accordingly. Regarding the using the guava methanol extract as a positive control, is because in 2012 it was noted by the scientist that the population of citrus psyllid was low in the orchards where guava is grown as compared to the orchards where only citrus plants are grown. Which open a new door in citrus psyllid management. The repellent activity of guava methanol extract was not significant as compared to our treatment. However, there is a considerable repellent activity of guava is reported in literature.

 

Reviewer 4 Report

Totally, the methods, results and conclusions are scientifically sound. In this study, the authors have determined the ovicidal toxicity and antifeedant activity of Artemisia absinthium essential oil (AAEO) against the Asian citrus psyllid (ACP) Diaphorina citri Kuwayama and the toxicity against the worker honeybees Aphis mellifera L. as the non-target organism. Additionally, they have explored the effects of AAEO on settling behavior, fitness and development of ACP. Their findings will greatly contribute to provide valuable information for the biocontrol of ACP in the citrus groves. However, this manuscript has many errors as details in the lists of major and minor concerns including many grammatical and spelling errors, and word usage problems as currently written.

Major concerns: 

1. I strongly recommend the authors abbreviate Artemisia absinthium essential oil as AAEO according to the common abbreviation rules.

2. In the section of Abstract, the authors showed AAEO with the LC50 value of 24.40 mg/mL against ACP. However, I can’t find out this value throughout the manuscript. Please check it.

3. For Figure 1, the authors should use the full name of ACP in the Y-axis or firstly provide the abbreviation of ACP in the first sentence of Introduction. In addition, the different treatments should be marked with different colors in order to be easily distinguished in the Figures 1 and 2.

4. For Table 4, “LD50 and LD90” should be replaced with “LC₅₀ and LC₉₀”, respectively. Additionally, the concentration of imidacloprid should be provided for the mortality listed in the third column. The same issue should be checked in the “2.7.”.

5. I strongly recommend the authors should re-edit References according to MDPI Reference List and Citations Style Guide (https://www.mdpi.com/authors/references). Especially, the first letter of each word in the reference titles don’t need to be capitalized except for the first word or special noun. The Latin name of a specie should be in italic. In addition, the journal name should be abbreviated correctly.

Minor concerns:

Please revise them in the attachment carefully.     

Comments for author File: Comments.pdf

The English language should be re-edit carefully.  If possible,  the revised manuscript should be proofread by a native English speaker before resubmission.

Author Response

Reviewer 4. Totally, the methods, results and conclusions are scientifically sound. In this study, the authors have determined the ovicidal toxicity and antifeedant activity of Artemisia absinthium essential oil (AAEO) against the Asian citrus psyllid (ACP) Diaphorina citri Kuwayama and the toxicity against the worker honeybees Aphis mellifera L. as the non-target organism. Additionally, they have explored the effects of AAEO on settling behavior, fitness and development of ACP. Their findings will greatly contribute to provide valuable information for the biocontrol of ACP in the citrus groves. However, this manuscript has many errors as details in the lists of major and minor concerns including many grammatical and spelling errors, and word usage problems as currently written.

Major concerns: 

1. I strongly recommend the authors abbreviate Artemisia absinthiumessential oil as AAEO according to the common abbreviation rules.
2. In the section of Abstract, the authors showed AAEO with the LC50 value of 24.40 mg/mL against ACP. However, I can’t find out this value throughout the manuscript. Please check it.
3. For Figure 1, the authors should use the full name of ACP in the Y-axis or firstly provide the abbreviation of ACP in the first sentence of Introduction. In addition, the different treatments should be marked with different colors in order to be easily distinguished in the Figures 1 and 2.
4. For Table 4, “LD50 and LD90” should be replaced with “LC₅₀and LC₉₀”, respectively. Additionally, the concentration of imidacloprid should be provided for the mortality listed in the third column. The same issue should be checked in the “2.7.”.
5. I strongly recommend the authors should re-edit References according to MDPI Reference List and Citations Style Guide (https://www.mdpi.com/authors/references). Especially, the first letter of each word in the reference titles don’t need to be capitalized except for the first word or special noun. The Latin name of a specie should be in italic. In addition, the journal name should be abbreviated correctly.

 

Reply to Reviewer:  

We are thankful to you for your response and suggestions. The reviewer has provided comprehensive information and suggestions.

The AAEO has been changed to AAEO 

This information is updated in the discussion section. The LC50 value of 24.40 mg/mL against ACP was taken from our previous published paper.

In Fig 2 full name of ACP in the Y-axis is now changed accordingly.

LD50 and LD90” should be replaced with “LC₅₀ and LC₉₀ has been changed, and the concentrations used for imidacloprid is mentioned in the table and also in 2.7.

MDPI reference style has been updated accordingly.

Minor concerns:

Please revise them in the attachment carefully.   

Reviewer 5 Report

The article entitled “Evaluation of Artemisia absinthium. L, essential oil as a potential novel prophylactic against the Asian citrus psyllid Diaphorina citri Kuwayama” deals the toxicity of Artemisia absinthium essential oil (ABEO) to Diaphorina citri Kuwayama. And the results indicate that ABEO exhibits toxic and behavioral effects on D. citri that could be useful for managing this pest. In my opinion, this is an experimental complete manuscript, but there are some problems. For example, the concentration of ABEO in the paper is different for bees and D. citri, which I hope can be explained. In addition, there are literature citation format inconsistency, such as the third paragraph in Introduction part. And I have some suggestions for the article as follows.

1.       The last sentence in the Simple Summary part should be grammatically consistent.

2.       I think the description of the results of the positive control is not accurate in 3.1 part of Result. We can obviously see from the figure that there is a difference with the control group, and it is significant at 48 and 72 hours.

3.       The three pictures in FIG. 1 should be clearly marked A,B, and C, and the third picture in is not completely displayed. The same problem exists in the subsequent graph.

4.       There is no punctuation mark on how the first sentence and the second sentence are broken in in 3.2 part of Result, and parentheses are not required to describe the first sentence in Figure 2.

5.       It is recommended to put the last sentence of Result sections 3.2 and 3.3 in the discussion section.

6.       The result of adult rate of sweet orange pot treated by ABEO was not shown in the statistical table of 3.3 part of Result.

7.       The notes in Table 2 are not seen in the table.

8.       3.4.1 should be changed to 3.4 in Result part.

9.       The legend in Figure 3-Figure 6 is usually in the upper right corner. In addition, the male and female colors in figure 3 and figure 4 should be as consistent as possible. In Figure 4, mx should be male age-specific fecundity.

10.   In the section 3.5 results, why is it not compared with its own Table 2 results, but compared with 15 literatures?

1.       The last sentence in the Simple Summary part should be grammatically consistent.

Author Response

Reviewer 5.

The article entitled “Evaluation of Artemisia absinthium. L, essential oil as a potential novel prophylactic against the Asian citrus psyllid Diaphorina citri Kuwayama” deals the toxicity of Artemisia absinthium essential oil (ABEO) to Diaphorina citri Kuwayama. And the results indicate that ABEO exhibits toxic and behavioral effects on D. citri that could be useful for managing this pest. In my opinion, this is an experimental complete manuscript, but there are some problems. For example, the concentration of ABEO in the paper is different for bees and D. citri, which I hope can be explained. In addition, there are literature citation format inconsistency, such as the third paragraph in Introduction part. And I have some suggestions for the article as follows.

Reply to Reviewer:  

We are thankful to you for your response and suggestions.

1. The last sentence in the Simple Summary part should be grammatically consistent.
2. I think the description of the results of the positive control is not accurate in 3.1 part of Result. We can obviously see from the figure that there is a difference with the control group, and it is significant at 48 and 72 hours.
3. The three pictures in FIG. 1 should be clearly marked A, B, and C, and the third picture in is not completely displayed. The same problem exists in the subsequent graph.
4. There is no punctuation mark on how the first sentence and the second sentence are broken in in 3.2 part of Result, and parentheses are not required to describe the first sentence in Figure 2.
5. It is recommended to put the last sentence of Result sections 3.2 and 3.3 in the discussion section.
6. The result of adult rate of sweet orange pot treated by ABEO was not shown in the statistical table of 3.3 part of Result.
7. The notes in Table 2 are not seen in the table.
8. 3.4.1 should be changed to 3.4 in Result part.
9. The legend in Figure 3-Figure 6 is usually in the upper right corner. In addition, the male and female colors in figure 3 and figure 4 should be as consistent as possible. In Figure 4, mx should be male age-specific fecundity.
10. In the section 3.5 results, why is it not compared with its own Table 2 results, but compared with 15 literatures?

FIG. 1 one is marked with A, B and C. The Third picture is changed and same as the graph also changed.

Thanks for these comments. The positive control results are issue is now resolved.

The sentence is revised and now the meaning is clear.

Result sections 3.2 and 3.3's last sentence has been shifted to the discussion section.

The results why are it not compared with its own Table 2 results. The Table 2 is ovicidal activity we assessed, that’s why we not compared with this table. The reference we given is our own previous published paper in which we already constructed the dose range for citrus psyllid.

 

Comments on the Quality of English Language

1. The last sentence in the Simple Summary part should be grammatically consistent.

Reply to Reviewer:  

The last sentence in the Simple Summary grammatical issue is resolved now.

Reviewer 6 Report

The manuscript is very good, and the subject matter is relevant. I made some comments and suggestions about the pdf.

Comments for author File: Comments.pdf

Author Response

Reviewer 6.

 

The manuscript is very good, and the subject matter is relevant. I made some comments and suggestions about the pdf.

 

Reply to Reviewer:  

 

We are thankful to you for your response and suggestions. All the issues raised in the PDF were resolved.

Round 2

Reviewer 2 Report

The authors have addressed my concerns. 

There are minor typographycal errors throughout the manuscript. The en dash, not hyphen, should be used for number ranges in the main body of the ms and page ranges in the references section. The minus symbol should be used for enantiomers of chemical names. The symbols -1 and / for units are mixing; these symbols should be unified. 

Author Response

We are thankful to the reviewer for his time and suggestions. These suggestion’s improve our manuscript quality. We have revised according to the suggestions by reviewer, hopeful these amendments are accordingly.

Reviewer 4 Report

The authors have revised the manuscript according to my suggestions and answered these questions point by point. I’m satisfied with almost all revisions they have made, but some issues still need to be addressed. So I think this manuscript needs to be addressed with minor revision.  

Minor concerns: 

1. In Line 23, “Artemisia absinthium” needs to be in italic.

2. In Line 63, “Nicotiana tabacum” does not use the dark background. The similar issue needs to be addressed in Lines 75, 107, 119, 122, 134, 147, 252, 255, 263, 268, 321, 331 and 354.

3. In Line 77, “A. absinthium (AAEO)” should be revised as “A. absinthium essential oil (AAEO)”.

4. In Line 92, “four °C” should be written as “4 °C”.

5. In Line 93, “Artemisia absinthium essential oil” should be abbreviated as “AAEO”.

6. In Lines 125-126, “petri dish” should be corrected as “Petri dish”.

7. In Line 134, “25 cm long, 20 cm wide”should be revised as “25 cm length, 20 cm width”.

8. In Line 164, delete the excessive space between “of” and “AAEO”.

9. In Line 201, add a full point behind “(Figure 2)”.

10. In Lines 305 and 307, “50 % lethal concentration” and “90% lethal concentration” should be revised as “LC₅₀. 50 % lethal concentration” and “LC₉₀. 90% lethal concentration”, respectively.

11. For Lines 325-327, 328-347 and 348-349, these three paragraphs should be integrated into a paragraph.

12. In Line 413, “Environ Sci Pollu Res Inter”should be corrected as “Environ. Sci. Pollut. Res.”.

13. For References, the title did not need to be in italic, except for Latin name of the species. Additionally, the journal name should be abbreviated and in italic, for example, “Journal of Plant Pathology” should be abbreviated as “J. Plant Pathol.”. Please check and revise them carefully.

Minor editing of English language needs to b required.

Author Response

We are thankful to the reviewer for his time and suggestions. These suggestion’s improve our manuscript quality. We have revised according to the suggestions by reviewer, hopeful these amendments are accordingly. All the issues raised by the reviewever were resolved now.