Yeast Species, Strains, and Growth Media Mediate Attraction of (Diptera: Drosophilidae).

Specific ecological interactions between insects and microbes have potential in the development of targeted pest monitoring or control techniques for the spotted wing drosophilid, (Matsumura), an exotic invasive pest of soft fruit. To evaluate attraction to yeast species from preferred types of fruit, three yeasts were isolated from blackberry fruit and two yeasts from raspberry fruit and used to bait simple plastic bottle traps. and were identified from blackberries, whereas a different strain was identified from raspberry. Yeast identification was based on sequence analysis of the D1/D2 domain of the large subunit 26S rRNA gene. Commercial baker's yeast () was similar or more effective for the capture of males and females than yeasts isolated from blackberry or raspberry when grown in sucrose. However, when grown in corn syrup, a strain of from blackberry captured the highest number of females and a strain of isolated from raspberry captured high numbers of males and females. Species of , , and from a laboratory yeast collection did not outperform baker's yeast in pairwise tests when grown in sucrose solution or yeast-peptone-dextrose medium. The raspberry strain of grown in corn syrup outperformed grown in sucrose, in terms of captures in baited traps under laboratory conditions. We conclude that yeast species, strain, and growth medium can have a marked influence on attraction to baited traps, a finding that could assist in the development of yeast-related monitoring or control techniques targeted at this pest.