MORPHOLOGICAL AND MOLECULAR DESCRIPTION OF NEW RECORD OF METARHABDITIS RAINAI (NEMATODA: RHABDITIDAE) FROM BAGHDAD
DOI:
https://doi.org/10.36103/5cdt4s17Keywords:
Entomopathogenic nematode, Iraq, Morphometric, Soil, 18S rRNA geneAbstract
Aim of this study was to identify and characterize the entomopathogenic nematode Metarhabditis rainai, which was isolated from soil samples carried out from Alrashdya at (33˚25ˈ13.4̎ N 44˚21ˈ45.3̎ E) Baghdad- Iraq and was illustrated by both morphological and molecular aspects. All specimens of M. rainai were cultured, identified and described using some morphometric criteria based on standard available key. Selected specimens (Zah, IQ2 OR960470 isolate) of this species were characterized by the body length of male was ranged from (377.49 – 563.89 μm), the body length of female was (857.44 – 1111.7 μm) and the body length of juvenile was (419.28 – 757 μm). Using partial 18S rRNA gene sequences, molecular characterization was performed on selected specimens of this species. The 18S-rRNA sequence of the Zah, IQ2 OR960470 isolate showed a sequence homology ranging from (88.50% to 100%) with the 18S rRNA sequence of M. rainai found in the NCBI database. The phylogenetic tree has been created to separate M. rainai species from closely related genera and species. Metarhabditis rainai Zah, IQ2 OR960470 isolate marks the first record of M. rainai in Iraq.
Received: 11/9/2024
Accepted: 4/12/2024
Published: 28/02/2026
References
1. Asif, M., J. S. Prasad, R. Khan, N., Somasekhar and Q. Tahseen. 2013. A revision of the genus Metarhabditis (Nematoda: Rhabditidae) with description of three known species, a key to the identification of congeners and discussion of their relationships. Journal of Natural History, 47(41-42): 2599-2622.
https://doi:10.1080/00222933.2013.798702
2. Al-Zaidawi, J. B., J. Karimi and E. M. Moghadam. 2019. Molecular characterizations of the entomopathogenic nematodes, Heterorhabditis bacteriophora and Oscheius myriophilus from Iraq. Egyptian Journal of Biological Pest Control, 29(1): 38.
https://doi:10.1186/s41938-019-0136-6
3. Beier, S. and W. Traunspurger. 2003. Seasonal distribution of free-living nematodes in the Körsch, a coarse-grained submountain carbonate stream in southwest Germany. Nematology, 5: 481–504. https://doi: 10.1163/156854102765216740
4. Bhat, A. H., S. Srivastava, A. Rana, A. K. Chaubey, R. Machado and J. Abolafia. 2020. Morphological, morphometrical, and molecular characterization of Metarhabditis amsactae Ali, Pervez, Andrabi, Sharma and Verma, 2011; Sudhaus, 2011 (Rhabditida, Rhabditidae) from India and proposal of Metarhabditis longicaudata as a junior synonym of M. amsactae. Journal of Nematology, 52 (1):116.
https://doi: 10.21307/jofnem-2020-116
5. Bhat, A. H., S. Gautum, A. Rana, A. K. Chaubey, J. Abolafia and V. Půža. 2021. Morphological, morphometrical and molecular characterization of Oscheius siddiqii Tabassum and Shahina, 2010 (Rhabditida, Rhabditidae) from India with its taxonomic consequences for the subgenus Oscheius Andrássy, 1976. Biology, 10(12): 1239.
https://doi: 10.3390/biology10121239
6. De Brida, A. L., J. M. O. Rosa, C. M. G. D. Oliveira, B. M. D. C. E. Castro, J. E. Serrão, J. C. Zanuncio and S. R. S. Wilcken. 2017. Entomopathogenic nematodes in agricultural areas in Brazil. Scientific Reports, 7(1): 45254.
https://doi: 10.1038/srep45254
7. Dillman, A. R., J. M. Chaston, B. J. Adams, T. A. Ciche, H. Goodrich-Blair, S. P. Stock and P. W. Sternberg. 2012. An entomopathogenic nematode by any other name. PLoS Pathogens, 8(3): e1002527. https://doi: 10.1371/journal.ppat.1002527
https://doi:10.1371/journal.pone.0051785
8. Eyualem-Abebe, J. Mees and A. Coomans. 2001. Nematode communities of Lake Tana and other inland water bodies of Ethiopia. Hydrobiologia, 462: 41–73. https://doi: 10.1023/A:1013176117586
9. Fonseca, V.G., G.R. Carvalho, W. Sung, H.F. Johnson, D.M. Power, S.P. Neill, M. Packer, M. L. Blaxter, P. J. D. Lambshead, W. K. Thomas and S. Creer. 2010. Second-generation environmental sequencing unmasks marine metazoan biodiversity. Nature Communications, 1(1): 98. https://doi: 10.1038/ncomms1095
10. Gagarin, V. G. 2000. Fauna of free-living nematodes from the littoral of Kurilskoe Lake (Russia, Kamchatka Peninsula) and description of Rhitis eximius sp. n. (Nematoda, Rhabditida). Inland Water Biology, 4: 21-28.
11. Heyns, J. 2002. Checklist of free-living nematodes recorded from freshwater habitats in Southern Africa. Water SA, 28: 449–456.
12. Khanum, T. A., S. Javed and N. Mehmood. 2019. Description of new species of Metarhabditis longicaudata (Nematoda: Rhabditidae) with three new records from Sindh, Pakistan. Plant Protection, 3(03): 131-139. https://doi: 10.33804/pp.003.03.3110
13. Kumar S., G. Stecher and K. Tamura. 2016. MEGA7: Molecular Evolutionary Genetics Analysis version 7.0 for bigger datasets. Molecular Biology and Evolution 33 (7):1870-1874.
https://doi: 10.1093/molbev/msw054
14. Lambshead, P. J. D. 2004. Marine Nematode Diversity. In: Chen, Z.X., Chen, S.Y., Dickson, D.W., eds. Nematology: Advances and Perspectives. Volume 1: Nematode Morphology, Physiology and Ecology. Beijing: Tsinghua University Press, 438–468.
15. Loof, P. A. A. 1973. Freshwater nematodes from Surinam collected by J. van der Land. Zoologische- Verhandelingen, 129: 1–46.
16. Morise H, E. Miyazaki, S. Yoshimitsu and T. Eki. 2012. Profiling Nematode Communities in Unmanaged Flowerbed and Agricultural Field Soils in Japan by DNABarcode Sequencing. PLoS ONE 7(12): e51785.
17. Nguyen, K. and D. Hunt. 2007. Entomopathogenic nematodes: Systematics, Phylogeny and bacterial Symbionts. Brill, 5: 59-119.
18. Stock, S. and D. Hunt. 2005. Morphology and Systematics of nematodes used in biocontrol. In:Grewal S, Ehlers R-U,Shapiro-Ilan D(eds). Nematodes as biocontrol agents. CABI, Oxford-shire, UK, 3-43. https://doi:10.1079/9780851990170.0003
19. Timm, R.W. 1971. Antarctic soil and freshwater nematodes from McMurdo Sound region. Proceedings of the Helminthological Society of Washington, 38: 42–52.
20. Tomazini, M. D., M. M. Aguillera, R. C. Rodrigues, R. Bessi, R. Harakava and C. D. Oliveira. 2013. Biometric and molecular analysis of Brazilian isolate of Rhabditis rainai (Nematoda: Rhabditidae). Nematologia Brasileira, 37: 1-8.
21. Traunspurger, W. 2000. The biology and ecology of lotic nematodes. Freshwater Biology, 44: 29–45.
https://doi:10.1046/j.1365-2427.2000.00585.x
22. Trejo‐Meléndez, V. J., J. Ibarra‐Rendón and J. Contreras‐Garduño. 2024. The evolution of entomopathogen in nematodes. Ecology and Evolution, 14(2): p.e10966.
https://doi:10.1002/ece.10966
23. Wanless, F.R. and R. Hunter. 2001. Freshwater Nematodes from Loch Ness, Scotland, Part I. The Orders Tylenchida Thorne, 1949 and Rhabditida Chitwood, 1933 (Nematoda, Secernentea). Bulletin-Natural History Museum London (Zoology), 67: 1–24.
24. Ye, W., A. Torres-Barragan and Y. J. Cardoza. 2010. Oscheius carolinensis n. sp. (Nematoda: Rhabditidae), a potential entomopathogenic nematode from vermicompost. Nematology, 12(1):121-35. https://doi: 10.1163/156854109X458464
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Zahraa Y. Kadhim, Harith S. Al-Warid , Jawad B. Al-Zaidawi

This work is licensed under a Creative Commons Attribution 4.0 International License.

2.jpg)
