Article Figures & Data
Figures
- FIG. 1.
Acquisition of GFP-tagged E. coli by Mediterranean fruit flies exposed to contaminated feed. Flies were exposed for 24 h to a 20% sucrose solution supplemented with different numbers of tagged E. coli cells. Male and female flies were collected separately, and the number of Ampr, GFP-expressing bacteria in 20 flies was determined.
- FIG. 2.
Mediterranean fruit flies acquire E. coli from contaminated fecal material. Flies were exposed to a 20% sucrose solution or fecal material enriched with 2 × 109 CFU/ml GFP-labeled E. coli for 20 h. The numbers of labeled bacteria in males and females were determined. Flies could efficiently acquire E. coli from both the sucrose solution and fecal material in similar numbers. Bacteriological determinations were performed with batches of 10 males and 10 females per replicate (three replicates per treatment).
- FIG. 3.
Survival of E. coli on contaminated Mediterranean fruit flies. Flies were exposed to a sucrose solution supplemented with 4.6 × 109 CFU/ml of E. coli for 20 h. After this, a sample of 10 to 20 flies was collected each day from the cage and subjected to microbiological analysis. Day 1 refers to the 24 h after the beginning of exposure. No E. coli was detected on preexposure flies.
- FIG. 4.
Visualization of E. coli in the Mediterranean fruit fly by fluorescence microscopy. Flies were fed a 20% sucrose solution supplemented with 109 CFU/ml GFP-expressing E. coli. (A) Micrograph of the labelum under UV light, with bacteria clearly present in the pseudotrachea of the labelum (arrows). (B) Fine structure of the labelum with associated fluorescent bacteria at a higher magnification. Bars, 100 μm.
Tables
- TABLE 1.
Presence of coliforms and E. coli in wild Mediterranean fruit fliesa
Sampling location Ecosystem type No. of flies in sample No. of coliforms (CFU/fly) No. of E. coli (CFU/fly)b Beth-Dagan 1 Mixed citrus orchard 16 1.3 × 104 Beth-Dagan 2 Mixed citrus orchard 23 4.9 × 104 1.1 × 104 Kfar-Saba Home gardens with bearing fruit trees in rural areas 3 Rehovot Home gardens with bearing fruit trees in urban areas 4 —c —c ↵ a Mediterranean fruit fly samples were obtained from different geographic locations in central Israel and different ecosystems. Flies samples were collected with McPhail traps loaded with Biolure. The traps were exposed for 2 weeks during March and April 2004.
↵ b Presumptive identification as E. coli.
↵ c Bacteria were detected following enrichment.
