Commercial Yellow Sticky Strips more attractive than yellow boards to western cherry fruit fly (Dipt., Tephritidae)

Abstract

Bright yellow sticky rectangles made of paper boards were previously identified as the most effective traps for capturing western cherry fruit fly, Rhagoletis indifferens Curran (Dipt., Tephritidae). However, no data on the effectiveness of commercial sticky yellow plastic traps against R. indifferens have been reported. In tests conducted in sweet cherry trees [Prunus avium (L.) L.] in Washington state (USA) using ammonium carbonate as the chemical lure, commercial plastic 'Yellow Sticky Strips' made of translucent high-impact polystyrene captured~two or three times more flies than commercial sticky yellow-folded Pherocon â AM and Alpha Scents boards. Yellow Sticky Strips also minimized captures of non-target flies and bees per surface area compared with Pherocon â AM and/or Alpha Scents boards. Trap size and adhesive type were not factors for greater catches of R. indifferens. However, more flies were caught on the shadefacing side of Yellow Sticky Strips, which was brightly illuminated, than on the shade-facing side of boards, which was darker, suggesting differential light passage was a factor. The Yellow Sticky Strips could be very useful for monitoring R. indifferens in detection programmes and based on the results of this study can replace yellow boards. They are also useful because they are relatively unattractive to non-target insects.

Attraction ofRhagoletis indifferens(Diptera: Tephritidae) to White Light in the Presence and Absence of Ammonia

“…However, here only 1 light deployment method was tested. Furthermore, as stated earlier, ammonia odor alone does not make all yellow traps equally effective at catching flies (Yee 2012(Yee , 2014, so improving the efficacy of ammonia-baited traps is possible. Some possibilities to explore with light include deploying different white color temperatures and stronger lights that cover a larger area, using lights with a different yellow trap, and changing the position of the bulb relative to the trap and sun.…”

“…Rhagoletis pomonella flies locate host fruit visually if fruit are apparent, and by host odor if fruit are not apparent (Aluja & Prokopy 1993). It is unclear if ammoniabaited traps are similarly located, i.e., by using vision if traps are unobstructed from view, but this seems possible because traps of certain colors or shapes catch more flies than other traps despite the same ammonia stimulus (Burditt 1988;Yee 2014). If they are, then the bulb light stimulus may be weaker than both yellow color and ammonia stimuli in the field.…”

“…One bulb was hung ~2 cm above a sticky rectangle trap. Except in experiment 5, the trap was a 14 by 23 cm sticky yellow plastic sheet covered with a pressure sensitive adhesive (AgriSense-BCS Limited, South Wales, United Kingdom) that is highly attractive to R. indifferens in the field (Yee 2014). In experiment 5, the trap was a 14 by 23 cm clear styrene plastic sheet (Plastruct, Industry, California) covered with a thin layer of Tanglefoot® adhesive (Contech Enterprises, Inc., Victoria, British Columbia, Canada).…”

“…Responses to various types of light have been studied in some muscid and calliphorid flies (Zablocka 1972;Meyer 1978;Pickens 1989;Smallegange 2004), but have not been well studied in diurnal Diptera, including in the economically important family Tephritidae. In contrast, many studies have been done on responses of tephritids to color and other visual cues, especially as they relate to traps (e.g., Prokopy 1968Prokopy , 1986Greany et al 1977;Owens & Prokopy 1984, 1986Yee 2014Yee , 2015.…”

“…Traps for detecting the fly are typically baited with ammonia, a highly attractive olfactory cue (Frick 1952). Sunlight transmitted through translucent yellow panel traps baited with ammonia has been shown to increase fly captures (Yee 2014), suggesting light from bulbs near traps could be used to increase trap efficacy. Despite this observation, whether light associated with traps with or without ammonia can increase fly captures in the field is unknown.…”