Steinernema africanum n. sp. (Rhabditida, Steinernematidae), a New Entomopathogenic Nematode Species Isolated in the Republic of Rwanda

0564704 - BC 2023 RIV US eng J - Journal Article
Machado, R. A. R. - Bhat, A. H. - Abolafia, J. - Shokoohi, E. - Fallet, P. - Turlings, T. C. J. - Tarasco, E. - Půža, Vladimír - Kajuga, J. - Yan, X. - Toepfer, S.
Steinernema africanum n. sp. (Rhabditida, Steinernematidae), a New Entomopathogenic Nematode Species Isolated in the Republic of Rwanda.
Journal of Nematology. Roč. 54, č. 1 (2022), č. článku 20220049. ISSN 0022-300X
Institutional support: RVO:60077344
Keywords : biocontrol agents * nematode morphology * phylogenetics
OECD category: Zoology
Impact factor: 1.3, year: 2022
Method of publishing: Open access
https://sciendo.com/article/10.2478/jofnem-2022-0049

Alternatives to hazardous insecticides are urgently needed for an environmentally friendly and effective management of insect pests. One such option is the use of entomopathogenic nematodes (EPN). To increase the availability of EPN with potential for biocontrol, we surveyed agricultural soils in the Republic of Rwanda and collected two Steinernema isolates. Initial molecular characterization showed that they represent a new species, for which we propose the name S. africanum n. sp. To describe this new species, we reconstructed phylogenetic relationships, calculated sequence similarity scores, characterized the nematodes at the morphological level, conducted crossing experiments, and isolated and characterized their symbiotic bacteria. At the molecular level, S. africanum n. sp. is closely related to S. litorale and S. weiseri. At the morphological level, S. africanum n. sp. differs from closely related species by the position of the nerve ring and also because the stoma and pharynx region is longer. The first-generation males have ventrally curved spicules with lanceolate manubrium and fusiform gubernaculum and the second-generation males have rounded manubrium and anteriorly hook-like gubernaculum. Steinernema africanum n. sp. does not mate or produce fertile progeny with any of the closely related species.
Permanent Link: https://hdl.handle.net/11104/0338671