Morphological and Molecular Characterization of the Potato Rot Nematode, Ditylenchus destructor, Parasitizing Garlic in Korea
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors“Morphological and Molecular Characterization of the Potato Rot Nematode, Ditylenchus destructor, Parasitizing Garlic in Korea”.
The manuscript entitled “Morphological and Molecular Characterization of the Potato Rot Nematode, Ditylenchus destructor, Parasitizing Garlic in Korea” provides new data on occurrence of Ditylenchus destructor in garlic cultivation in Korea.
I have suggestions which in my opinion can improve the presented manuscript.
Manuscript submitted for a revision can be recommended for publication in Horticulturae after major revision.
Abstract
Line 17: Ditylenchus sp. or Ditylenchus destructor?
Key words: I think that key word Korea should be added.
Introduction
Line 31: Allium L. Liliaceae Juss.
Line 38: After the year 2006 a few species from genus Ditylenchus have been described (D. gigas D. arachis, Ditylenchus laurae); update references cited, please.
Ditylenchus- italics; Ditylenchus Filipjev, 1936
Lines 39-40: Give Latin names of plants.
Lines 40-41: Ditylenchus dipsaci (Kühn, 1857) Ditylenchus destructor Thorne, 1945
Lines 40-42: Give references.
Line 40: The publication cited is about D. dipsaci. Give citations concerning distribution of other plant parasitic species from the genus Ditylenchus.
Lines 48-55: Two ecotypes of garlic plants are mentioned in this fragment of the manuscript. What differs these two ecotypes?
Material and Methods
Lines 71-74: What was an area/acreage of fields?
Line 74: Table 1 should be placed in a section Results (3.1).
Lines 100-101: Please include morphological and anatomical features that were observed and showed in photos.
Line 103: Molecular analysis.
Table 1: Give the information in which province the geographical regions are localized.
Results
Line 141: It is not clear: Frequency of occurrence of Ditylenchus sp. from garlic in Korea or Frequency of occurrence of Ditylenchus destructor from garlic in Korea.
Line 142: Ditylenchus sp. or Ditylenchus destructor?
Line 150: As above.
Table 2: Detection frequencies of the genus Ditylenchus in South Korea in 2020 to 2022 or Detection frequencies of Ditylenchus destructor in South Korea in 2020 to 2022?
Ditylenchus sp. or Ditylenchus destructor?
Lines 149-151: Ditylenchus sp. or Ditylenchus destructor? At what infestation the symptoms were observed?
Figure 1: Ditylenchus sp. or Ditylenchus destructor?
Table 3: Why only one population of D. destructor was morphologically characterized? What is a localization of presented population? Why measurements of females were only presented? Measurements and characteristics of males should be also included. The manuscript could be more interesting if there were more populations characterized.
Figure 2B: Lateral field is not clearly visible.
Figures 5-6: Why only these sequences of D. destructor were included into molecular and phylogenetic study?
Line 218: “The results showed that the species has been widely distributed.” It is not clear because D. destructor was isolated from 6% of samples.
Discussion
Line 219: Give Latin name of ginseng.
The discussion showed important aspects of garlic cultivation in Korea, including D. destructor. I think that it could improve the discussion if the variability of features of specimens isolated from garlic was compared with that of specimens sampled from other plants.
Author Response
Dear reviewer, thanks for your valuable comments and suggestions.
This manuscript reports on the survey of the infection status of Ditylenchus species parasitizing garlic in Korea. During this process, Ditylenchus destructor was discovered, and its damage symptoms, morphological characteristics, and genetic traits were analyzed. Ultimately, this study reports the occurrence of D. destructor, which causes rot disease in garlic, in Korea.
In response to the reviewer's comments, we have included morphometric results of males and provided a comparative analysis with the population first reported from ginseng in Korea.
Although it would have been ideal to conduct a morphological analysis of populations by different geographical regions, the primary goal of our study at the time was to investigate the occurrence of plant-parasitic nematodes in garlic. Therefore, a broader analysis was not conducted. The objective of this manuscript is to first report the occurrence of D. destructor in Korean garlic fields, and since there were no significant morphological differences between regions, we believe that additional regional analysis is not essential for this manuscript. We analyzed additional populations that could support the regional distribution of D. destructor and performed molecular identification.
Thank you,
Sincerely,
Reviewer 2 Report
Comments and Suggestions for AuthorsAll comments are showed in the Reviewed manuscript.
Comments for author File: 
Comments.pdf
Author Response
Dear reviewer, thanks for your valuable comments and suggestions.
A revised manuscript has been made based on the reviewer's comments.
The objective of this manuscript is to first report the occurrence of D. destructor in Korean garlic fields, and since there were no significant morphological differences between regions, we believe that additional regional analysis is not essential for this manuscript. We conducted an additional analysis of populations that could support the regional distribution of D. destructor and performed molecular identification.
Thank you,
Sincerely,
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsDear Authors,
The manuscript has been improved but there are a few suggestions that haven’t been taken under consideration.
Manuscript submitted for a revision ca be recommended for publication in Horticulturae after minor revision.
Sincerely yours,
· Lines 104-105: Add other metrics includes in the study.
· Ditylenchus spp. were isolated from 6% of samples. What was a real frequency of D. destructor in all samples collected?
· Specimens morphologically characterized were isolated form one sample or it is a mixture from different samples?
· What is a localization of the sample/samples in which D. destructor was found?
· How many males were measured?
· At what infestation level of D. destructor the symptoms shown in a Fig 1A were observed ?
· Females/males of D. destructor are not clearly visible - Fig 1B. Entire body of the nematode is presented in Fig 2A.
· Discussion on variability of D. destructor populations isolated from different host plants should follow the fragment of the text concerning the nematode occurrence.
Author Response
Dear Reviewer,
Thank you very much for your insightful comments and suggestions regarding our manuscript.
1) Lines 104-105: Add other metrics includes in the study.
A: Revised.
2) Ditylenchus spp. were isolated from 6% of samples. What was a real frequency of D. destructor in all samples collected?
A: We believed that Ditylenchus sp. was isolated from 6% of samples, and populations of the species were all identified as D. destructor based on morphological traits from 2020 to 2022.
3) Specimens morphologically characterized were isolated form one sample or it is a mixture from different samples?
A: Characterized specimens are one population in Namhae, Gyeongnam, Korea.
4) How many males were measured?
A: 10 individuals of male
5) At what infestation level of D. destructor the symptoms shown in a Fig 1A were observed ?
A: The infected density was described.
6) Females/males of D. destructor are not clearly visible - Fig 1B. Entire body of the nematode is presented in Fig 2A.
A: Figure 1B shows the presence of this nematode in garlic peel.
7) Discussion on variability of D. destructor populations isolated from different host plants should follow the fragment of the text concerning the nematode occurrence.
A: Revised.
We believe that your input has significantly contributed to improving the quality of our work.
Once again, thank you for your valuable comments.
Best regards,
Authors
