Temporal accumulation of phenylpropanoids in male fruit flies, <Emphasis Type="Italic">Bactrocera dorsalis</Emphasis> and <Emphasis Type="Italic">B. carambolae</Emphasis> (Diptera: Tephritidae) following methyl eugenol consumption

Summary. Males of dacine tephritids, Bactrocera carambolae and B. dorsalis are strongly attracted to, and compulsively feed on methyl eugenol (ME), a potent attractant for many Bactrocera species. While ME was shown to be biotransformed into phenylpropanoids, 2-allyl-4,5-dimethoxyphenol and (E)-coniferyl alcohol, and temporarily stored in the rectal gland of male B. dorsalis prior to release during courtship at dusk, B. carambolae male produces only the latter compound along with its de novo synthesized pheromone components. Both species were also shown to have different age-related response, sensitivity and consumption levels of ME. Here, we monitored and compared temporal changes in the accumulation profiles of these phenylpropanoids by the two sibling species, with male rectal glands being individually excised at different time intervals from 15 minutes to 20 days after initial ME feeding and analysed quantitatively. Results are discussed in light of plant-fruit fly co-evolution relationship.     

Development and application of three-dimensional potential source contribution function (3D-PSCF)

A potential source contribution function (PSCF) can indicate the source areas of high air pollutant concentrations using backward trajectories. However, the conventional two-dimensional PSCF (2D-PSCF) cannot consider the emission and transport height of air pollutants. That missing information might be critical because injection height varies depending on the source type, such as with biomass burning. We developed a simple algorithm to account for the height of trajectories with high concentrations and combined it with the conventional PSCF to devise 3D-PSCF. We demonstrate the applicability of the 3D-PSCF by applying it to particulate PAH data collected from September 2006 to August 2007 in Seoul. We found variation in the results from 3D-PSCF with threshold heights from 3,000 to 1,500 m. Applying 2,000 m as the threshold height in the PSCF calculation most clearly determined the possible source areas of air pollutants from biomass fuel burning that were affecting the air quality in Seoul.