Physiological status ofDrosophila suzukii(Diptera: Drosophilidae) affects their response to attractive odours

Abstract

An improved understanding of the biology of the invasive pest, Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), is critical for the development of effective management strategies. Trapping is one technique used for both detection and control; however, the efficacy of trapping can vary depending on the target insect's physiological state, its behavioural priorities and the type of attractant used in the trap. We conducted a series of caged trapping experiments and a greenhouse trapping experiment to investigate the effects of D. suzukii feeding status, age, mating status, ovipositional status and seasonal morph type on the capture rate of traps baited with fermentation odours. Starved flies were trapped at greater rates compared to fed flies; more virgin flies were trapped than mated flies; flies deprived of an oviposition substrate were trapped more frequently than flies given an oviposition substrate. It is still unclear whether age or seasonal morphology affect bait response. Lastly, a caged choice experiment investigated the relationship between female reproductive status and attraction to fermentation or fruit odours. Fermentation‐based traps captured female flies regardless of their reproductive status but, ripe fruit‐based traps were more attractive to flies with more than seven eggs. In summary, studies that use fermentation‐based traps should recognize that capture rates of D. suzukii will depend on the feeding, mating and oviposition experiences of the population; also, fruit‐based traps may better target gravid females.

Interactions among morphotype, nutrition, and temperature impact fitness of an invasive fly

“…Other studies also found that D. suzukii fed protein + sugar diets as adults matured eggs, whereas those fed only sugar diets had very few to no eggs (Plantamp et al, 2017;Wong, Wallingford et al, 2018). Similarly, one study showed that D. melanogaster has the highest egg production on P:C 1:4 diet (Lee et al, 2008), but others have reported that D. melanogaster has higher fecundity in medium-…”

“…Overwintered WM females were 78 days old (since adult emergence, after cold hardening and overwintering) and SM were 1 day old (since emergence) when they were paired with males and placed into diet/temperature treatments. Previous studies that describe physiological differences between WM and SM (Kirkpatrick et al, ; Wong, Wallingford, Loeb, & Lee, ) have not taken into account the effect of an overwintering period. Therefore, rather than exposing WM and SM to the exact same pre‐treatment conditions, our intention was to simulate what WM would encounter with increasing temperatures after overwintering as adults, and what SM emerging in late summer would experience with decreasing temperatures during autumn.…”

Influences of blackberry margins on population dynamics of Drosophila suzukii and grape infestation in adjacent vineyards

“…During grape ripeness (period 3), the sex ratio switched towards a higher proportion of males in traps but not in vacuum captures (Supporting Information A4) of BB sites and was male-biased at all sites in period 4. These findings may be partly explained by trap baits being more attractive to females at certain periods, depending on their physiological status, related to their age, feeding, mating and ovipositional status, etc (Wong, Wallingford, Loeb, & Lee, 2018). Gravid females prefer fruit over fermentation odours (Abraham et al, 2015;Keesey, Knaden, & Hansson, 2015), and may thus be less likely to be caught by the traps.…”

Impact of phagostimulants on effectiveness of OMRI‐listed insecticides used for control of spotted‐wing drosophila (Drosophila suzukii Matsumura)

“…It does not appear that species of yeast explains our lack of phagostimulant effects. The response of D. suzukii to fermentation-based substances is influenced by physiological status (Wong, Wallingford, Loeb, & Lee, 2018). Unmated females and females with few eggs show preference for fermentation odours and transition to fruit odours after mating and as their egg loads increase (Wong et al, 2018).…”

“…The response of D. suzukii to fermentation-based substances is influenced by physiological status (Wong, Wallingford, Loeb, & Lee, 2018). Unmated females and females with few eggs show preference for fermentation odours and transition to fruit odours after mating and as their egg loads increase (Wong et al, 2018). Knight et al (2015) used flies that were 3-4 day old, while we used flies that were 4-10 day old and were all likely mated and ready to lay eggs.…”