Submitted to: Acta Horticulturae
Publication Type: Proceedings
Publication Acceptance Date: 2/27/2017
Publication Date: N/A
Interpretive Summary: We developed the methodology for conducting bench-top assays for evaluating the oviposition and feeding preference as well as the fecundity (egg viability) of the spotted wing drosophilla (SWD) on bluebrry cultivars and germplasm. This will enable breeders to search for and identify SWD resistance in blueberry cultivars, germplasm, and wild blueberry accessions.
Technical Abstract: The objective of the study was to develop an effective screening method for evaluating resistance to the Spotted Wing Drosophilla (SWD, and to locate resistance in southern adapted blueberry germplasm including the hexaploid rabbiteye (Vaccinium asheii Reade = V. virgatum Aiton) and the tetraploid southern highbush (V. corymbosum L. complex hybrid. One hundred berries were sampled from 88 blueberry genotypes were examined for the presence or absence of SWD feeding damage or egg laying. In laboratory bioassays using no-choice arenas, clutch size for SWD (number of eggs per fruit) as well as total brood per fruit were assessed after 3 days and these counts correlated with berry quality attributes that were independently recorded for each variety or accession before SWD infestation [berry weight, percentage soluble solids (Brixo), and harvest seasonality (early-, mid-, and late-season harvest)]. No antibiosis could be detected among blueberry or blackberry hosts tested in our experiments; SWD flies within 3 days lay anywhere from 5 to 10 viable eggs per host fruit. SWD fecundity (viable eggs) and total brood production was strongly associated with sugar levels in blueberry fruit.