title: Interactions Between Frankliniella fusca and Pantoea ananatis in the Center Rot Epidemic of Onion (Allium cepa).
abstract: An Enterobacteriaceae bacterium, Pantoea ananatis (Serrano) Mergaert, is the causal agent of an economically important disease of onion, center rot. P. ananatis is transmitted by an onion-infesting thrips, Frankliniella fusca (Hinds). However, interactions between F. fusca and P. ananatis as well as transmission mechanisms largely remain uncharacterized. This study investigated P. ananatis acquisition by thrips and transstadial persistence. Furthermore, the effects of bacterial acquisition on thrips fitness were also evaluated. When thrips larvae and adults were provided with acquisition access periods (AAP) on peanut leaflets contaminated with the bacterium, an exponentially positive relationship was observed between AAP and P. ananatis acquisition (R(2) ≥ 0.77, P = 0.01). P. ananatis persisted in thrips through several life stages (larvae, pupae, and adult). Despite the bacterial persistence, no significant effects on thrips fitness parameters such as fecundity and development were observed. Immunofluorescence microscopy of adult thrips with P. ananatis-specific antibody after 48 h AAP on contaminated food revealed that the bacterium was localized only in the gut. These results suggested that the pathogen is not circulative and could be transmitted through feces. Mechanical inoculation of onion seedlings with fecal rinsates produced center rot symptoms, whereas inoculation with rinsates potentially containing salivary secretions did not. These results provide evidence for stercorarian transmission (transmission through feces) of P. ananatis by F. fusca.
authors.affiliation: First and second authors: Department of Plant Pathology, University of Georgia, Tifton 31793; third, fifth, and sixth authors: Department of Entomology, University of Georgia, Tifton 31793; and fourth author: Complex Carbohydrate Research Center, University of Georgia, Athens 30602.
authors.forename: Bhabesh
authors.initials: B
authors.lastname: Dutta
authors.affiliation: First and second authors: Department of Plant Pathology, University of Georgia, Tifton 31793; third, fifth, and sixth authors: Department of Entomology, University of Georgia, Tifton 31793; and fourth author: Complex Carbohydrate Research Center, University of Georgia, Athens 30602.
authors.forename: Ronald
authors.initials: R
authors.lastname: Gitaitis
authors.affiliation: First and second authors: Department of Plant Pathology, University of Georgia, Tifton 31793; third, fifth, and sixth authors: Department of Entomology, University of Georgia, Tifton 31793; and fourth author: Complex Carbohydrate Research Center, University of Georgia, Athens 30602.
authors.forename: Apurba
authors.initials: A
authors.lastname: Barman
authors.affiliation: First and second authors: Department of Plant Pathology, University of Georgia, Tifton 31793; third, fifth, and sixth authors: Department of Entomology, University of Georgia, Tifton 31793; and fourth author: Complex Carbohydrate Research Center, University of Georgia, Athens 30602.
authors.forename: Utku
authors.initials: U
authors.lastname: Avci
authors.affiliation: First and second authors: Department of Plant Pathology, University of Georgia, Tifton 31793; third, fifth, and sixth authors: Department of Entomology, University of Georgia, Tifton 31793; and fourth author: Complex Carbohydrate Research Center, University of Georgia, Athens 30602.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Marasigan
authors.affiliation: First and second authors: Department of Plant Pathology, University of Georgia, Tifton 31793; third, fifth, and sixth authors: Department of Entomology, University of Georgia, Tifton 31793; and fourth author: Complex Carbohydrate Research Center, University of Georgia, Athens 30602.
authors.forename: Rajagopalbabu
authors.initials: R
authors.lastname: Srinivasan
mesh_terms: D000818:Animals; D010367:Arachis / Q000382:microbiology*; D005243:Feces / Q000382:microbiology; D007303:Insect Vectors / Q000382:microbiology*; D007814:Larva; D019697:Onions / Q000382:microbiology* / Q000469:parasitology; D020636:Pantoea / Q000166:cytology / Q000502:physiology*; D010935:Plant Diseases / Q000382:microbiology* / Q000469:parasitology; D018515:Plant Leaves / Q000382:microbiology; D036226:Seedlings / Q000382:microbiology; D061149:Thysanoptera / Q000382:microbiology*