Submitted to: PLoS One
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/14/2013
Publication Date: 4/12/2013
Citation: Bellamy, D.E., Hall IV, W.A., Sisterson, M.S., Walse, S.S. 2013. The development of a host potential index and its postharvest application to the spotted wing drosophila, Drosophila suzukii (Diptera: Drosophilidae). PLoS One. 8(4):e61227. Interpretive Summary: The Host Potential Index (HPI) is a flexible, practical tool for quantifying insect preference or host suitability, as well as the strength of that potential relationship, in a variety of situations. It is used, here, as a way to rank the potential of several commercially important commodities (blackberries, blueberries, cherries, grapes, peaches, raspberries, and strawberries) to serve as hosts for the spotted wing drosophila (SWD) in a postharvest scenario. The model examines and evaluates three components involved with SWD host selection: attraction to host volatiles, oviposition behavior, and development. Due to the number of commercial crops that might serve as possible hosts, the development of a host potential index for SWD would assist scientists, agricultural practitioners, and regulators working within this system in prioritizing research and control efforts for each crop. The work was made available to trade partners (showing the low potential for table grapes to serve as SWD hosts) and used in part to open trading channels for California table grapes exported to Australia and New Zealand.
Technical Abstract: Novel methodology is presented for indexing the relative potential of hosts to function as resources. Results from studies examining host selection, utilization, and physiological development of the organism resourcing the host were combined and quantitatively related via a Host Potential Index (HPI). Several aspects of the HPI are addressed including: 1) model derivation; 2) influence of experimental design (no choice, two-choice, and multiple-choice); 3) model testing; 4) variable selection and weighting; and, 5) potential applications. The HPI was applied to spotted wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), and seven “reported” hosts (blackberries, blueberries, sweet cherries, grapes, peaches, raspberries, and strawberries) in a postharvest scenario. Four aspects of SWD-host interaction were examined: attraction to host volatiles; population-level oviposition performance; individual-level oviposition performance; and several key developmental factors. Results indicated that raspberries (HPI1,7 = 350.5) have the greatest potential to serve as a postharvest host for SWD relative to the other fruit hosts, with grapes (HPI7,7 = 248.8) having the least potential. The HPI provides a practical framework to quantify relative host potential based one or more independent studies.