|SUBBOTIN, SERGEI - California Department Of Food And Agriculture|
|KANTOR, MIHAIL - Oak Ridge Institute For Science And Education (ORISE)|
|GRABOWSKI, MICHELLE - Minnesota Department Of Agriculture|
Submitted to: Journal of Nematology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/3/2021
Publication Date: 11/3/2021
Citation: Handoo, Z.A., Skantar, A.M., Subbotin, S., Kantor, M.R., Hult, M.N., Grabowski, M. 2021. Molecular and morphological characterization of a first report of Cactodera torreyanae Cid del Prado Vera & Subbotin, 2014 (Nematoda: Heteroderidae) from Minnesota, the United States of America. Journal of Nematology. https://doi.org/10.21307/jofnem-2021-093.
Interpretive Summary: Plant-parasitic nematodes are microscopic worms that feed on plants and cause an estimated ten billion dollars of crop losses each year in the United States and 100 billion dollars globally. The cyst nematodes are an important group, with many species that cause significant economic and yield losses on potato. In this study, a team of ARS scientists and colleagues from Minnesota and California analyzed anatomical and molecular traits to identify a cyst nematode called Cactodera torreyanae, isolated from a potato in Minnesota. This discovery is significant because it represents the first report of this nematode from the United States and the first report of this cyst nematode species from potato fields. This report will serve as a useful guide to researchers and diagnosticians identifying important cyst nematodes from the genus Cactodera.
Technical Abstract: Cactodera torreyanae Cid del Prado Vera & Subbotin, 2014 cysts were discovered during a Pale Potato Cyst Nematode (PCN) survey conducted by Minnesota Department of Agriculture as part of the Animal and Plant Health Inspection Service (APHIS) efforts to survey states for the presence of PCN. The soil samples were collected from a potato field, located in Karlstad, Kittson County, Minnesota, USA. Two out of 175 vials submitted for identification to the Mycology and Nematology Genetic Diversity and Biology Laboratory (MNGDBL) contained few cysts and juveniles of C. torreyanae. Cysts were dark brown in color, lemon-shaped to elongated with distinct vulval cone. Vulva with denticles present around fenestra, cyst length to width ratio between 1.6 to 2.3 and anus distinct. The juveniles had rounded stylet knobs, some sloping slightly posteriorly. The molecular analysis included sequence and phylogenetic analysis of ITS rRNA, D2-D3 expansion segments of 28S rRNA and COI of mtDNA genes. The nematode species was identified by both morphological and molecular means as Cactodera torreyanae. To our knowledge this represents the first report of Cactodera torreyanae from the United States and first report of this cyst nematode species from potato fields. Definite host plant for this nematode remains unknown.