| Title: | Preferential infectivity of entomopathogenic nematodes in an envenomed host |
| Author(s): | Mbata GN; Shapiro-Ilan DI; Alborn HT; Strand MR; |
| Address: | "Agricultural Research Station, Fort Valley State University, 1005 University Drive, Fort Valley, GA 31030, USA. USDA, Agricultural Research Service, Southeastern Fruit and Tree Nut Research Laboratory, 21 Dunbar Road, Byron, GA 31008, USA. Electronic address: David.Shapiro@ARS.USDA.gov. USDA-ARS Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL 32608, USA. Department of Entomology, University of Georgia, Athens, GA 30602, USA" |
| DOI: | 10.1016/j.ijpara.2019.05.002 |
| ISSN/ISBN: | 1879-0135 (Electronic) 0020-7519 (Linking) |
| Abstract: | "Entomopathogenic nematodes and parasitoid wasps are used as biological control agents for management of insect pests such as the Indian meal moth, Plodia interpunctella. The parasitoid wasp Habrobracon hebetor injects a paralytic venom into P. interpunctella larvae before laying eggs. A previous study reported that the entomopathogenic nematode Heterorhabditis indica preferentially infects P. interpunctella that have been envenomed by H. hebetor while results in this study showed a similar preference by the entomopathogenic nematode, Steinernema glaseri. We therefore tested four hypotheses for why nematode infection rates are higher in envenomed hosts: (1) elevated CO(2) emission from envenomed hosts attracts nematodes, (2) paralysis prevents hosts from escaping nematodes, (3) volatile chemicals emitted from envenomed hosts attract nematodes and increase infection, and (4) reduced immune defenses in envenomed hosts increase nematode survival. Results showed that envenomed P. interpunctella larvae emitted lower amounts of CO(2) than non-envenomed larvae. Physical immobilization of P. interpunctella larvae did not increase infection rates by S. glaseri but did increase infection rates by H. indica. Emissions from envenomed hosts were collected and analyzed by thermal desorption gas chromatography/mass spectrometry. The most abundant compound, 3-methyl-3-buten-1-ol, was found to be an effective cue for S. glaseri attraction and infection but was not an effective stimulus for H. indica. Envenomed P. interpunctella exhibited a stronger immune response toward nematodes than non-envenomed hosts. Altogether, we conclude that different mechanisms underlie preferential infection in the two nematode species: host immobilization for H. indica and chemical cues for S. glaseri" |
| Keywords: | "Animals Biological Assay Carbon Dioxide/metabolism Female Moths/immunology/*parasitology Pest Control, Biological/methods Rhabditida/immunology/*physiology Strongyloidea/immunology/*physiology Volatile Organic Compounds/metabolism Wasp Venoms/*metabolism;" |
| Notes: | "MedlineMbata, George N Shapiro-Ilan, David I Alborn, Hans T Strand, Michael R eng Research Support, U.S. Gov't, Non-P.H.S. England 2019/07/16 Int J Parasitol. 2019 Aug; 49(9):737-745. doi: 10.1016/j.ijpara.2019.05.002. Epub 2019 Jul 12" |
