|SUBBOTIN, SERGEI - California Department Of Agriculture|
|KANTOR, MIHAIL - Oak Ridge Institute For Science And Education (ORISE)|
|VIEIRA, PAULO - Virginia Tech|
|AGUDELO, PAULA - Clemson University|
Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/24/2021
Publication Date: 12/1/2021
Citation: Skantar, A.M., Handoo, Z.A., Subbotin, S.A., Kantor, M., Vieira, P., Agudelo, P., Hult, M.N., Rogers, S.T. 2021. Molecular and morphological evidence for the first report of Seville root-knot nematode, Meloidogyne hispanica (Nematoda: Meloidogynidae) in the USA and North America. Journal of Nematology. https://doi.org/10.21307/jofnem-2021-098.
Interpretive Summary: Nematodes are microscopic worms that cause billions of dollars in crop losses worldwide each year. Root-knot nematodes are an important group of nematodes that damage many kinds of plants, including corn, by invading the roots and interfering with nutrient uptake. Identifying these nematodes from soil can be very labor intensive and anatomical features of root knot nematodes are very similar in some species. In the present study, scientists from Beltsville, MD along with researchers from California and South Carolina, identified the Seville root-knot nematode for the first time from corn in South Carolina. Corn is an important crop in South Carolina, worth an estimated $218 million in 2020. The results are important for tracking the spread of root-knot nematodes into new crops and regions so that steps to limit the damage can be implemented. This research will be used by researchers and diagnosticians to accurately detect the Seville root knot nematodes from infested fields and for directing management decisions related to corn cultivation.
Technical Abstract: A high number of second stage juveniles of the root-knot nematode were recovered from soil samples collected from a corn field, located in Pickens County, South Carolina, USA in 2019. Extracted nematodes were examined morphologically and molecularly for species identification which indicated that the specimens of root knot juveniles were Meloidogyne hispanica. The morphological examination and morphometric details from second-stage juveniles were consistent with the original description and redescriptions of this species. The ITS rRNA, D2-D3 expansion segments of 28S rRNA, intergeneric COII-16S region, nad5 and COI gene sequences were obtained from the South Carolina population of M. hispanica. Phylogenetic analysis of the intergenic COII-16S region of mtDNA gene sequence alignment using statistical parsimony showed that the South Carolina s population clustered with Meloidogyne hispanica from Portugal and Australia. To our best knowledge, this finding represents the first report of Meloidogyne hispanica in the USA and North America.