Biocontrol Potential of Some Entomopathogenic Fungal Strains Against Bean Aphid Megoura japonica (Matsumura)

Round 1

Reviewer 1 Report

This article, Biocontrol potential of some entomopathogenic fungal strains against bean aphid” by Nam et al. has reported results of a laboratory study, where authors have used few strains of two already known entomopathogenic fungi, Verticillium lecanii and Beauveria bassiana. In this study, authors have compared the mortality of aphids to each of the four strains and their combinations. Also, they have tested the conidial isolates and filtrate form of the fungal colonies. It was reported that one of the B. bassiana (B76) isolated had the highest efficacy to the aphids when used as filtrate form.

This article has some interesting results to share with the readers. But this article needs much revision for the usage of the English language. Besides, the results presented in the current form is not much helpful or interesting to the audience. Therefore, I suggest a few revisions and many corrections for this manuscript.

1. More information is needed in the Materials and Methods section of the manuscript. For example, what stage of the aphid was used in the bioassay. Similarly, how or where fungi isolates were collected?
2. The “data analysis” section needs some improvement and details. Rephrase sentence. I think the main objective of this study is to see the potential effect/ mortality of four fungal isolates on bean aphids. If that is true, I would not consider time as a factor as with increasing time insect mortality tend to increase under these settings. Therefore, consider removing those ANOVA tables. Rather you should include a commercial strain to compare the efficacy of the four strains used in your study so that you can show the potential benefit of these strains.
3. a graph is too busy and difficult to follow. See how you can simplify it. May be keeping the two species separate.
4. On the Y-axis of Fig. 1, 2 and 3, what you are measuring? Isn’t this insect mortality? If so, please say %mortality.
5. The discussion section will only be interesting when you include some standard or positive control. We already know that these fungi can kill insects including aphids. There is nothing new to it, but people would be only interested if these are equally or even more virulent strains of the two common fungi currently in the market for killing insects.

Some suggestions for editorial corrections:

1. Line 18. Showed “the” maximum effect. Also, you can delete the effect and replace it with mortality.
2. All scientific names should be in italics. Do not keep using both the common names and scientific names all the time. Just choose one. Also, no need to mention the author name after the scientific name of the organism each time you mention. Just in the beginning of the article.
3. Line 29. “Bean aphid is spread in large areas in the world”. Not a good sentence, rephrase
4. “use” not “using” in line 35
5. “sucking insect pests”, not “suck” in line 42
6. “entomopathogenic” not “entomopathogen”in line 44
7. “harmful” not “harmfulness” in line 45
8. “residual activity” not “remaining activity” in line 45
9. Analysis of the factorial variance of the factors…(line 117), not a correct expression of statistical analysis
10. Delete “seventh” line 186-187

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 2 Report

General comments

The experiment deals with a very important, and actual topic. Biological protection is of increasing importance in order to reduce the use of synthetic pesticides. The impact of insect pathogenic fungi on sucking insects is an interesting and important topic, and this well-designed research attempts to investigate systematically their effects on bean aphids. The used method slightly differs from that published by IRAC, but it is appropriate for the particular study and in some aspects it is even more detailed, though there is a lack of detailing in the processing and presentation of the data. The conclusions section needs to be supplemented.

The subject is of great practical importance, therefore I recommend it for processing further.

Specific comments

The bibliographic review, if numbered, usually starts with 1 and continue as follows. The manuscript lines up the used bibliography in alphabetical order, but the last reference begins with the letter "A".

L. 32 After our best knowledge, many synthetic insecticides, used in appropriate conditions, are not dangerous, so the “dangerous” attributive should be replaced.

L. 49 Entomopathogenic fungus is not toxic to insects, this is not the correct expression, this word should be replaced

Data analyses and Figure 1,2,3
Have all of the dead aphids treated with the insect pathogen fungus been confirmed to be killed by the fungus? Since aphids have also died in the control treatment as shown in the figure, it can be assumed that the answer is no. If so, the rate of non-insect pathogen fungus death should also be reported, with the observation that the statistical analysis was performed only on individuals affected by fungal mortality. The current columns could represent this by an inserted separating horizontal line, with the lower section showing other causes of death, and the upper columns showing the individuals killed by a fungal infection. The statistical analysis should be performed only on the upper part of the chart, and this should be shown and explained under the chart.

Figure 1 The letter-codes are barely visible, slipped, the diagram is difficult to follow.

Figure 1,2,3 The error bars should represent the 95% confidence interval of the mean.

L. 212 The results do not conclude that there is no synergistic effect on the combined use of the four strains, but rather inhibition is to be observed, since B76 alone reached 85.3%, whereas L2 + L5 + B76 + B252 achieved only 69.4%. What is the reason for this decline? This section needs further, more detailed (if possible bibliographically based) explanation.

Author Response

Comments and Suggestions for Authors

General comments

The experiment deals with a very important, and actual topic. Biological protection is of increasing importance in order to reduce the use of synthetic pesticides. The impact of insect pathogenic fungi on sucking insects is an interesting and important topic, and this well-designed research attempts to investigate systematically their effects on bean aphids. The used method slightly differs from that published by IRAC, but it is appropriate for the particular study and in some aspects it is even more detailed, though there is a lack of detailing in the processing and presentation of the data. The conclusions section needs to be supplemented.

The subject is of great practical importance; therefore, I recommend it for processing further.

Ans.: We really appreciate your consensus with our paper. Experiment in this paper may help biocontrol agents application in field. And we have tried to improve our paper based on your suggestions. Many thanks.

Specific comments

Point 1: The bibliographic review, if numbered, usually starts with 1 and continue as follows. The manuscript lines up the used bibliography in alphabetical order, but the last reference begins with the letter "A".

Ans.: Already corrected

Point 2: L. 32 After our best knowledge, many synthetic insecticides, used in appropriate conditions, are not dangerous, so the “dangerous” attributive should be replaced.

Ans.: Already corrected

Point 3: L. 49 Entomopathogenic fungus is not toxic to insects, this is not the correct expression, this word should be replaced

Ans.: Already corrected

Point 4: Data analyses and Figure 1,2,3

Have all of the dead aphids treated with the insect pathogen fungus been confirmed to be killed by the fungus? Since aphids have also died in the control treatment as shown in the figure, it can be assumed that the answer is no. If so, the rate of non-insect pathogen fungus death should also be reported, with the observation that the statistical analysis was performed only on individuals affected by fungal mortality. The current columns could represent this by an inserted separating horizontal line, with the lower section showing other causes of death, and the upper columns showing the individuals killed by a fungal infection. The statistical analysis should be performed only on the upper part of the chart, and this should be shown and explained under the chart.

Ans.: Good suggestion. We tried to analyze the factor causing the death of aphids. In fact, there a slight percent of dead aphids by different cause (not only toxic of Entomopathogenic fungus), on the other hand, we would like to focus on the effect of Entomopathogenic fungus which is the key material of this study.

Point 5: Figure 1 The letter-codes are barely visible, slipped, the diagram is difficult to follow.

Ans.: Corrected

Point 6: Figure 1,2,3 The error bars should represent the 95% confidence interval of the mean.

Ans.: Corrected

Point 7: L. 212 The results do not conclude that there is no synergistic effect on the combined use of the four strains, but rather inhibition is to be observed, since B76 alone reached 85.3%, whereas L2 + L5 + B76 + B252 achieved only 69.4%. What is the reason for this decline? This section needs further, more detailed (if possible bibliographically based) explanation

Ans.: Really good question. We also wonder about this phenomenon and repeat our experiments several times. The results remain repeatable. In our opinion, most probably due to the reduced number of the spore of high virulence strain (B76 and L2) at the combination (B76 + L2 + B252 + L4), so its effect reduced significantly lower against M. japonica than other combinations

Author Response File: Author Response.docx

Reviewer 3 Report

Interesting study, but I recommend to improve it in many ways.

I indicated my remarks in the manuscript. I did not mark all mistakes, just examples of typical mistakes, so my suggestions can be applied to all similar cases. The most disturbing mistakes are the too general (and sometimes off-topic) statements, the unclear (and maybe misinterpreted) statistics, graphs and methodological descriptions.

I am not a native English speaker, but a series of typical grammatical mistakes were detectable even for me. I indicated some of them.

Comments for author File: Comments.pdf

Author Response

Reviewer 3

Comments and Suggestions for Authors

Interesting study, but I recommend to improve it in many ways.

I indicated my remarks in the manuscript. I did not mark all mistakes, just examples of typical mistakes, so my suggestions can be applied to all similar cases. The most disturbing mistakes are the too general (and sometimes off-topic) statements, the unclear (and maybe misinterpreted) statistics, graphs and methodological descriptions.

I am not a native English speaker, but a series of typical grammatical mistakes were detectable even for me. I indicated some of them.

Ans: We appreciate your revision of our paper. Our experiment in this paper was repeatable and will help the biocontrol fungi field application in future. We have corrected the indicated mistakes and re-read the whole text. Many thanks.

Point 1: Line 13: adding “of” and “of”

Ans: Corrected

Point 2: Line 18: adding “maximal mortality”

Ans: CorrectedPoint 3: Line 29: corrected: “aphid”

Ans: Corrected

Point 4: Line 30: corrected: “aphid”;

Ans: Corrected

       Point 5: Line 41: corrected: ‘’pesticides” and “are”

Ans: Corrected

Point 6: Line 42: corrected

Point 7: Line 43: corrected: “Pennetrate”

Ans: Corrected

Point 8: Line 44: corrected: “entomopathogenic”

Ans: Corrected

Point 9: Line 45: corrected

Point 10: Line 52: corrected: “Aphis fabae”

Ans: Corrected

Point 11: Line 66: corrected: “of”

Ans: Corrected

Point 12: Line 69: corrected

Point 13: Line 71: corrected: following the journal

Ans: Corrected

Point 14: Line 99: 3 replications (50 aphids/dish; 5 dish/treatment/replication)

Ans: CorrectedPoint

15: Line 109: Flat?

Ans.: Follow the reference

Point 16: Line 115: Corrected

Point 17: Line 123: corrected

Point 18: Figure 1: corrected (made clearly)

Ans: Corrected

Point 19: Line 131: Figure legend should contain all necessary information. Abbreviation of genera is not proper here, but actor name (Matsumara) should be erased after the scientific name of the aphid, indicate in the case of the entomopathogenic fungi as well

Ans.: Corrected

Point 20: Line 133: 10 aphids individual per dish?

Ans.: corrected, 50 aphids per dish.

Point 21: Line 175: corrected “Pathogens”

Ans.: Corrected

Point 22: Line 176: corrected “effective”

Ans.: Corrected

Point 23: Line 177: corrected “entomopathogenic”

Ans.: Corrected

Point 24: Line 192: corrected: “Graminum”

Ans.: Corrected

Point 25: Line 215: corrected.

Point 26: Line 320: corrected: “Acarology”

Ans.: Corrected

Point 27: Line 321: corrected: “Phytopathogen”

Ans.: Corrected

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The corrected version of the manuscript has addressed my previous comments. I just have one suggestion to correct the caption of the Y-axis of all the figures, where the word "mortality" is misspelled. 

Author Response

Comments and Suggestions for Authors

Q: The corrected version of the manuscript has addressed my previous comments. I just have one suggestion to correct the caption of the Y-axis of all the figures, where the word "mortality" is misspelled.

A: Thanks for your professional comments. We appreciate your efforts on this MS. As recommended, we have changed all the "mortality" of all figures correctly.

Author Response File: Author Response.docx

Reviewer 3 Report

I accept all the corrections. I indicated some minor mistakes in the revised manuscript.

Comments for author File: Comments.pdf

Author Response

Comments and Suggestions for Authors

We appreciate your efforts on this MS and thanks for your professional comments. We have corrected all sites noted in PDF version. You can check the following list we corrected.

1. "Potential" was capitalized on line 2.
2. "Matsumura" was deleted on line 24.
3. "M. japonica" was changed to bean aphid and italicized on line 95.
4. "M. japonica" was changed to bean aphid and italicized on 116.
5. "Development" was not capitalized on line 135.

Author Response File: Author Response.docx