تعیین مشخصات ریخت‌شناسی و مولکولی Pratylenchus mediterraneus Corbett, 1983 (Tylenchomorpha: Pratylenchidae) از ایران

نوع مقاله : علمی پژوهشی-فارسی

نویسندگان

1 دانشجوی کارشناسی ارشد بیماری‌شناسی گیاهی، گروه گیاه‌پزشکی، دانشکده کشاورزی، دانشگاه شهید چمران اهواز

2 استادیار بیماری‌شناسی گیاهی، گروه گیاه‌پزشکی، دانشکده کشاورزی، دانشگاه شهید چمران اهواز

چکیده

در این مطالعه، جمعیتی از جنس Pratylenchus در ارتباط با درختان گز از منطقه حفاظت شده کرخه بدست آمد. مطالعات ریخت‌شناسی، ریخت‌سنجی و مولکولی این جمعیت بر اساس توالی دو ناحیه D2-D3 از ژن 28S rRNA و ژن ITS rRNA نشان داد این جمعیت متعلق به گونهP. mediterraneus  می‌‌باشد. این جمعیت دارای ماده‌هایی به طول 431 تا 551 میکرومتر با کیسه ذخیره اسپرم پُر و استایلت به طول 15 تا 5/16 میکرومتر می‌باشد. نرهای جمعیت به دست آمده فعال بوده و دارای بدن به طول 331 تا 485، استایلت به طول 8/14 تا 15 و اسپیکول به طول 2/16 تا 19 میکرومتر می‌‌باشند. در آنالیز فیلوژنی با استفاده از توالی‌های ناحیه D2-D3 ژن 28S rRNA، توالی‌ جمعیت ایرانی به همراه توالی‌های دیگری از گونه P. mediterraneus و تعدادی از توالی‌هایی که به گونه P. thornei  تخصیص داده شده‌اند، در یک کلاد قرار گرفتند. این کلاد در ارتباط خویشاوندی نزدیک با کلادی است که توالی­‌های متعددی از گونه P. thornei را در بر‌گرفته است. در آنالیز فیلوژنی با استفاده از توالی­‌های ژن ITS rRNA، توالی‌ جمعیت ایرانی به همراه توالی‌های دیگری از گونه P. mediterraneus در یک کلاد قرار گرفتند. این کلاد در ارتباط خویشاوندی نزدیک با کلادی است که توالی‌های متعددی از گونه P. thornei را در بر‌گرفته است. ویژگی‎‌های ریخت‌شناسی، ریخت‌سنجی و توصیف جمعیت ایرانی این گونه در تحقیق حاضر برای اولین بار ارائه گردید.

کلیدواژه‌ها


عنوان مقاله [English]

Morphological and molecular characterization of Pratylenchus mediterraneus Corbett, 1983 (Tylenchomorpha: Pratylenchidae) from Iran

نویسندگان [English]

  • A. Abdolkhani 1
  • S. Azimi 2
1 MSc Student of Plant Pathology, Department of Plant Protection, Faculty of Agriculture, Shahid Chamran University of Ahvaz
2 Assistant professor of Plant Pathology, Department of Plant Protection, Faculty of Agriculture, Shahid Chamran University of Ahvaz
چکیده [English]

Background and Objectives
The Karkheh protected area is considered as one of the protected areas of Iran, which harbors a remarkable diversity of vegetation. A population belonging to the genus Pratylenchus was recovered and identified as P. mediterraneus during a survey on the biodiversity of the plant-parasitic nematodes in this region of Khuzestan province. This study aims to characterize the population based on the morphological and morphometric characteristics and evaluate its phylogenetic affinities using LSU D2-D3 and ITS rDNA sequences. Moreover, its phylogenetic relationships were investigated with other relevant genera and species.
Materials and Methods
Several soil samples were collected from the rhizosphere of tamarisk trees in Karkheh protected area. The centrifugal-floatation and tray methods were used for extracting the nematodes from the soil samples. The collected specimens were fixed and transferred to the pure glycerin after extracting the nematodes by using the modified De Grisse method. Then, permanent microscopic slides were prepared from the processed nematodes. The species was identified by using a light microscope equipped with a drawing tube based on the morphological and morphometric characteristics, and valid keys. The molecular phylogenetic analyses were performed by using partial sequences of the D2-D3 expansion segments of  the large subunit, and internal transcribed spacer (LSU D2-D3 and ITS rDNA) regions based on the Bayesian inference under the GTR + G + I model.
Results
A population of the genus Pratylenchus was recovered in the present study. The morphological, morphometric and molecular studies based on the D2-D3 domains of the 28S and ITS rRNA gene indicated that the recovered population belongs to P. mediterraneus. The morphological, morphometric, and molecular data of the Iranian population of the species were presented for the first time in this study. In the phylogenetic tree inferred using the 28S rRNA gene sequences, the newly generated sequence of the Iranian population of P. mediterraneus formed a clade with other sequences of the species, and some sequences assigned to P. thornei. All other sequences of P. thornei occupied a clade, in close phylogenetic relationship with the aforementioned clade. The newly generated sequence of the Iranian population formed a maximally supported clade with other sequences of the species in the phylogenetic tree inferred using the ITS rRNA gene.  
Discussion
The two species P. thornei and P. mediterraneus are morphologically very similar and can mainly be separated from each other by presence/absence of male and a functional spermatheca. Their separation is further corroborated by using the partial sequences of 28S and ITS rDNA. The sequences of the two species form the separate clades, and the identification of some sequences occupying the same clade with the sequences of P. mediterraneus need further validations in lack of the morphological data. 

کلیدواژه‌ها [English]

  • D2-D3 LSU
  • ITS
  • morphometrics
  • phylogeny
  • Pratylenchus thornei
Anonymous. 2021. General Department of Environmental Protection of Khuzestan Province, Department of Environment. Karkhe protected area. From https://khouzestan.doe.ir/portal/home
Barooti, S. 2006. Identification of plant parasitic and predator nematodes fauna of walnut trees in north and central of Iran. 17th Iranian Plant Protection Congress, 2-5 September, Karaj, Iran. P. 320.
Bruner, A. G., Gullison, R., Rice, E., and Da Fonseca, G. A. 2001. Effectiveness of parks in protecting tropical biodiversity. Science Journal, 291: 125-128.
Castillo, P., and Vovlas, N. 2007. Pratylenchus (Nematoda: Pratylenchidae): diagnosis, biology, pathogenicity and management.  Nematology Monographs and Perspectives 6 (Series Editors: Hunt, D.J. and Perry, R.N.). Leiden, The Netherlands, Brill.
Choi, D. R., Lee, J. K., Park, B. Y., Han, H. R., and Choi, Y. E. 2006. A new and one unrecorded species of Prafylenchus from Korea (Nematoda: Pratylenchidae). Journal of Asia-Pacific Entomology, 9: 5-9.
De Grisse, A. T. 1969. Redescription and modification of some techniques used in the study of nematodes phytoparasitaires. Mededelingen Rijksfacultiet Landbouw Wetenschappe Gent, 34: 351-369.
De la Peña, E., Moens, M., Van Aelst, A., and Karssen, G. 2006. Description of Pratylenchus dunensis sp. n. (Nematoda: Pratylenchidae), a root-lesion nematode associated with the dune grass Ammophila arenaria (L.) Link. Nematology 8: 79-88.
De Luca, F., Fanelli, E., Di Vito, M., Reyes, A., and De Giorgi, C. 2004. Comparison of the sequences of the D3 expansion of the 26S ribosomal genes reveals different degrees of heterogeneity in different populations and species of Pratylenchus from the Mediterranean region. European Journal of Plant Pathology, 110: 949-957.
De Luca, F., Reyes, A., Troccoli, A., and Castillo, P. 2011. Molecular variability and phylogenetic relationships among different species and populations of Pratylenchus (Nematoda: Pratylenchidae) as inferred from the analysis of the ITS rDNA. European Journal of Plant Pathology, 130: 415-426.
Di Vito, M., Greco, N., Halila, H. M., Mabsoute, L., Labdi, M., Beniwal, S. P. S., Saxena, M. C., Singh, K. B., and Solh, M. B. 1994. Nematodes of cool-season food legumes in North Africa. Nematologia Mediterranea, 22: 3-10.
Dudley, N., and Stolton, S. 2008. Defining protected areas: an international conference in Almeria, Spain. Gland, Switzerland: IUCN. 220 pp.
Filipjev I. N. 1936. On the classification of the Tylenchinae. Proceedings of the Helminthological Society of Washington, 3: 80-82.
Filipjev, I. N., and Schuurmans Stekhoven, J. H. 1941. A manual of agricultural helminthology. Leiden, The Netherlands, E. J. Brill.
Geraert, E. 2013. The Pratylenchidae of the world: identification of the family Pratylenchidae (Nematoda: Tylenchida). Academia Press. Ghent, Belgium.
Godfrey, G. H. 1929. A destructive root disease of pineapple and other plants due to Tylenchus brachyurus. Phytopathology 19: 611-629.
Graham, T. W. 1951. Nematode root rot of tobacco and other plants. Bulletin 390. South Carolina Agricultural Experiment Station, Clemson Agricultural College, 25 pp.
Greco, N., Di Vito, M., and Saxena, M. C. 1992. Plant parasitic nematodes of cool season food legumes in Syria. Nematologia Mediterranea, 20: 37-46.
Huson, D. H., and Scornavacca, C. 2012. Dendroscope 3: An interactive tool for rooted phylogenetic trees and networks. Systematic Biology, 61: 1061-1067.
Jenkins, W. R. 1964. A rapid centrifugal flotation technique for separating nematodes from soil. Plant Disease Reporter, 48: 692.
Movahedifar, E., and Azimi, S. 2020. New morphological observations on Pratylenchus thornei Sher & Allen, 1953 (Nematoda Pratylenchidae) based on the population from Iran. Redia-Giornale Di Zoologia, 103: 89-100.
Nguyen, H. T., Trinh, Q. P., Couvreur, M., Singh, P. R., Decramer, W., and Bert, W. 2019. Molecular and mor-phological characterisation of a new root-lesion nem-atode, Pratylenchus horti n. sp. (Tylenchomorpha: Pratylenchidae), from Ghent University Botanical Garden. Nematology, 21: 739-752.
Nunn, G. B. 1992. Nematode molecular evolution. Ph.D. Thesis, University of Nottingham, Nottingham, UK.
Nylander, J. A. A. 2004. MrModeltest v2. Evolutionary Biology Centre, Uppsala University, Sweden. Available online at https://github.com/nylander/MrModeltest2.
Orion, D., and Shlevin, E. 1989. Nematicide seed dressing for cyst and lesion nematode control in wheat. Journal of Nematology, 21: 629-631.
Sher, S. A., and Allen M. W. 1953. Revision of the genus Pratylenchus (Nematoda: Tylenchidae). University of California Publications in Zoology, 57: 441-470.
Pour Ehtesham, N., Azimi, S., and Pedram, M. 2021. First molecular characterisation of Helicotylenchus abunaamai Siddiqi, 1972 and H. dihystera (Cobb, 1893) Sher, 1961 (Tylenchomorpha: Hoplolaimidae) from Iran. Russian Journal of Nematology, 29: 11-22.
Rensch, D. 1924. Aphelenchus neglectus sp. n. eine neue parasitäre Nematodenart. Sonderabdruck aus dem Zoologischen Anzeiger 59: 277-280.
Ronquist, F., and Huelsenbeck, J. P. 2003. MrBayes 3: Bayesian phylogenetic inference under mixed models. Bioinformatics, 19: 1572-1574.
Sherbakoff, C. D., and Stanley, W. W. 1943. The more important diseases and insect pests of crops in Tennessee. Tennessee Agriculture Experiment Station Bulletin 186: 1-142.
Subbotin S. A., Perry, R., Warry, A., and Halford, P. 2000. Variations in ribosomal DNA sequences and phylogeny of Globodera parasitising solanaceous plants. Nematology, 2: 591-604.
Subbotin S. A., Ragsdale E. J., Mullens T., Roberts P. A., Mundo-Ocampo M., and Baldwin J. G. 2008. A phylogenetic framework for root-lesion nematodes of the genus Pratylenchus (Nematoda): evidence from 18S and D2-D3 expansion segments of 28S ribosomal RNA genes and morphological characters. Molecular Phylogenetics and Evolution, 48: 491-505.
Swofford, D. L. 2002. PAUP*. Phylogenetic Analysis Using Parsimony (*and Other Methods). Version 4.0b10. Sinauer Associates. Sunderland, MA.
Tamura, K., Stecher, G., Peterson, D., Filipski, A., and Kumar, S. 2013. MEGA6: molecular evolutionary genetics analysis version 6.0. Molecular Biology and Evolution, 30: 2725-2729.
Thorne, G., and Malek, R. B. 1968. Nematodes of the northern great plains. I. Tylenchida. South Dakota Agricultural Experimental Station, Technical Bulletin 31: 111 pp.
Troccoli, A., Subbotin, S. A., Chitambar, J. J., Janssen, T., Waeyenberge, L., Stanley, J. D., Duncan, L. W., Agudelo, P., Múnera Uribe, G. E., Franco, J., and Inserra, R. N. 2016. Characterisation of amphimictic and parthenogenetic populations of Pratylenchus bolivianus Corbett, 1983 (Nematoda: Pratylenchidae) and their phylogenetic relationships with closely related species. Nematology, 18: 651-678.
Troccoli, A., Fenelli, E., Castillo, P., Liébanas, G., Cotroneo, A., and De Luca, F. 2021. Pratylenchus vovlasi sp. nov. (Nematoda: Pratylenchidae) on raspberries in North Italy with a morphometrical and molecular characterization. Plants, 10: 1-15.
Waeyenberge, L., Viaene, N., and Moens, M. 2009. Species-specific duplex PCR for the detection of Pratylenchus penetrans. Nematology, 11: 847-857.
Whitehead, A. G., and Hemming, J. R. 1965. A comparison of some quantitative methods for extracting small vermiform nematodes from soil. Annals of Applied Biology, 55: 25-38.
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