Improving monitoring tools for spotted wing drosophila,Drosophila suzukii

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) were trapped in the field using colored plastic sphere traps coated with insect Tangle‐trap. Red and black spheres captured significantly more D. suzukii than white spheres. Translucent deli‐cup traps deployed in cherry orchards and baited with yeast, the Alpha Scents lure, or the Scentry lure captured significantly more flies than the Trécé lure and Suzukii bait; all attractants had poor selectivity for D. suzukii. No‐choice evaluations of attractants conducted in field cages corroborated the cherry orchard field study, though translucent deli‐cup traps provisioned with the yeast bait captured significantly more flies than those baited with the Alpha Scents lure. Red sphere traps baited with the Scentry lure captured 3–6× more flies than the deli‐cup trap baited with the same lure, and 3–4× more flies than the deli‐cup trap baited with yeast bait, demonstrating that a trap integrating both visual and olfactory cues is a superior tool for monitoring D. suzukii. Moreover, this simple sticky, dry trap design requires far less labor and maintenance than does a liquid‐based deli‐cup trap.     

Preferences by Rhagoletis indifferens (Diptera,Tephritidae) for rectangles of various yellow colours and fluorescence

Sticky rectangle traps of various yellow colours and fluorescence made of cardboard were field tested against western cherry fruit fly, Rhagoletis indifferens Curran, in paired trap preference experiments in Washington state. In a first experiment that involved comparisons of Alpha Scents (proprietary paint), Fluorescent Yellow (aerosol paint), Saffron Thread and Neon Light (semi‐gloss enamel paints) traps at two sites, the best performing trap was the Saffron Thread trap. In a second experiment comparing Citrus Splash (semi‐gloss enamel paint) with Alpha Scents and with Macaw and Lemon Zest (both semi‐gloss enamel paints) traps at a third site, the Citrus Splash trap outperformed the Alpha Scents trap. The Citrus Splash trap did not differ statistically from Saffron Thread and Lemon Zest traps, even though it caught 51% more flies than the Lemon Zest trap. The Alpha Scents trap caught significantly more non‐target Diptera than Fluorescent Yellow, Neon Light and Citrus Splash traps at two of three trap sites where non‐target Diptera populations were relatively high and overall it appeared less selective than the Citrus Splash trap. Results suggest that sticky rectangle traps painted semi‐gloss enamel Saffron Thread or Citrus Splash with low fluorescence could be highly useful for detecting R. indifferens.     

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

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^® AM and Alpha Scents boards. Yellow Sticky Strips also minimized captures of non‐target flies and bees per surface area compared with Pherocon^®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 shade‐facing 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.     

Effect of trap size, placement, and age on captures of blueberry maggot flies (Diptera: Tephritidae)

Ammonium acetate and protein hydrolysate baited and unbaited green spheres (3.6, 9.0, and 15.6 cm diameter) were evaluated for effectiveness in capturing blueberry maggot flies, Rhagoletis mendax Curran. Early in the season, baited spheres (9.0 cm diameter) captured significantly more R. mendax flies than spheres of 3.6 and 15.6 cm diameter. As the season progressed, the differences in trap captures became less pronounced among the 3.6-, 9.0-, and 15.6-cm-diameter spheres. In other experiments, the effects of trap positions and age on captures of blueberry maggot flies were assessed. Traps were positioned 15 cm above the bush canopy, 15 cm inside the canopy (from top of the bush), and 45 cm from the ground. Traps placed within the canopy captured 2.5 and 1.5 times as many flies compared with traps placed above the canopy and 45 cm from the ground, respectively. When sticky yellow Pherocon AM boards and green sphere traps were allowed to age in field cages, freshly baited (0 d) yellow sticky boards captured significantly more blueberry maggot flies than boards aged for 11, 28, and 40 d, respectively. No significant differences were observed among boards aged for 11, 28, and 40 d. However, when baited 9-cm sticky spheres were aged in field cages, there were no significant differences between freshly baited spheres and spheres aged for 11 and 28 d, respectively. Spheres aged for 40 d differed significantly from freshly baited ones. The study demonstrated that the baited 9-cm-diameter sphere was more effective in capturing blueberry maggot flies than spheres of 3.6 and 15.6 cm diameter. When this trap is deployed in the center of the bush canopy approximately 15 cm from the top of the bush, it is attractive and accessible to R. mendax flies. The data also indicated that a baited 9-cm sphere has a longer effective life span than Pherocon AM boards when deployed under the same field conditions.     

Comparison of two synthetic food-odor lures for captures of feral Mexican fruit flies (Diptera: Tephritidae) in Mexico and implications regarding use of irradiated flies to assess lure efficacy

Feral Mexican fruit flies, Anastrepha ludens (Loew) (Diptera: Tephritidae), were trapped in a citrus orchard in Mexico by using two types of synthetic food-odor lures, the AFF lure (Anastrepha fruit fly lure, APTIV, Inc., Portland, OR) and the BioLure (two-component MFF lure, Suterra LLC, Inc., Bend, OR). In Multilure traps (Better World Manufacturing, Inc., Miami, FL) containing water, BioLures captured about the same numbers of flies as AFF lures. In Multilure traps containing antifreeze solution, BioLures captured 2 and 5 times more flies than AFF lures in two experiments. BioLures, and AFF lures did not differ in attractiveness when used on sticky traps (Intercept trap, APTIV, Inc.; and sticky cylinder trap). Multilure traps captured >4 times as many flies as sticky traps with the exception that captures of females did not differ between Multilure and sticky traps baited with AFF lures. The percentage of females captured in Multilure traps was greater when traps were baited with BioLures compared with AFF lures, but the reverse was true for sticky traps. Sticky cylinder traps captured a higher percentage of females than Multilure traps. The most effective trap/lure combination was the Multilure trap baited with BioLure and antifreeze. In comparison with tests of these two lures in Texas, results were similar for Multilure traps, but they differed for sticky cylinder traps in that AFF lures were consistently more attractive than BioLures in Texas, but not in Mexico.     

Comparison of adult corn rootworm (Coleoptera: Chrysomelidae) sampling methods

Studies were conducted in Kansas corn and soybean fields during 1997 to compare various sampling methods, traps, and trap components for capturing three species of adult corn rootworms: western (Diabrotica virgifera virgifera Leconte), southern (D. undecimpunctata howardi Barber), and northern (D. barberi Smith & Lawrence). Lure constituents affected the species of beetle attracted to the trap. Traps with a lure containing 4-methoxycinnamaldehyde attracted more western corn rootworms, those with a lure containing eugenol were more attractive to northern corn rootworms, and those containing trans-cinnamaldehyde were most attractive to southern corn rootworms. Multigard sticky traps caught more beetles than did Pherocon AM sticky traps. In corn, a newly designed lure trap caught more beetles than did sticky traps on most occasions. Also, lure-baited sticky traps caught more beetles than did nonbaited sticky traps. Varying the color of the lure trap bottom did not affect the number caught. In soybeans, the new lure traps captured more beetles than did the nonbaited Multigard or Pherocon AM sticky traps. Results of this study suggest the new lure trap may provide a more accurate assessment of corn rootworm populations than traditional monitoring techniques and may be more esthetically pleasing to growers and consultants.     

A comparison of Lucitraps and sticky targets for sampling the blowfly Lucilia sericata

The Lucitrap (Miazma Pty Ltd, Queensland, Australia) combined with a synthetic odour bait, Lucilure (Miazma Pty Ltd, Queensland, Australia), is a commercially available trap for sampling and control of Lucilia cuprina (Wiedemann) in Australia. It was tested in Hungary against Lucilia sericata (Meigen) (Diptera: Calliphoridae), a cause of sheep strike throughout temperate Europe. The standard Lucitrap was tested against black or yellow sticky target traps. Both trap types were baited with either Lucilure or liver and 10% w/v sodium sulphide solution. With Lucilure as bait, L. sericata were caught on sticky traps but not in Lucitraps. With liver and sodium sulphide as bait, sticky traps caught 500-1500 times more L. sericata than Lucitraps. An adhesive sheet fitted to the top of a Lucitrap captured 30-300 times more L. sericata then were captured inside an unaltered Lucitrap. Direct observation of metallic green calliphorids (92.1% L. sericata) alighting on Lucitraps indicated that most flies stayed for a short while (modal class 2-4 s) and only a few stayed longer, to an observed maximum of 28 s. Flies explored a mean of 1.5 entry holes (range 0-7) during a visit but only 6% entered the trap. Size of L. sericata was not a physical barrier to Lucitrap entry, because many larger species were captured. However, L. sericata captured inside Lucitraps were significantly smaller than those captured on sticky traps, demonstrating that size was of behavioural importance. The data demonstrate that the Lucitrap is not effective as a trap for L. sericata in Hungary, due mainly to a failure of flies to enter the trap in large numbers. In Australia and South Africa, L. sericata is commonly caught in Lucitraps baited with Lucilure, although L. cuprina is more numerous. Our study highlights the potential for diversity of fly behaviour between different geographical populations of the same species. Such diversity can have a significant effect on the functioning of systems for fly sampling and control, when these systems depend for their success on certain behavioural responses of the target species.     

Attraction of adult Rhagoletis indifferens (Diptera: Tephritidae) to unbaited and odor-baited red spheres and yellow rectangles

Five sizes of red spheres (4, 6, 8, 10, and 12 cm diameter) and 2 orientations of yellow rectangles (vertical and V) were evaluated as unbaited sticky-coated traps for western cherry fruit flies, Rhagoletis indifferens Curran, in unmanaged cherry trees in Washington and Oregon. Red spheres that were 10 cm in diameter attracted more flies than red spheres that were 8 or 12 cm in diameter and significantly more flies than 4- or 6-cm spheres and yellow rectangles of either orientation. In a 2nd test, red spheres (10 cm diameter) baited with ammonium carbonate alone or ammonium carbonate plus putrescine attracted significantly more R. indifferens than similar spheres baited with ammonium acetate alone, putrescine alone, 3-methyl-1-butanol alone, or combinations of these substances. In a 3rd test, vertical yellow rectangles baited with ammonium carbonate alone attracted numerically more R. indifferens than any of the aforementioned substances alone or in combination. We discuss the potential value of 10-cm red spheres baited with ammonium carbonate for monitoring and direct control of R. indifferens.     

Efficacy of two synthetic food-odor lures for Mexican fruit flies (Diptera: Tephritidae) is determined by trap type

Sterile mass-reared Mexican fruit flies, Anastrepha ludens (Loew), were trapped in a citrus orchard by using multilure traps and cylindrical sticky traps baited with Advanced Pheromone Technologies Anastrepha fruit fly (AFF) lures or Suterra BioLure two-component (ammonium acetate and putrescine) MFF lures (BioLures). The cylinder trap/AFF lure combination was the best trap over the first 6 wk, the multilure trap/BioLure combination was best during weeks 6-12, and the multilure trap/AFF lure combination was best during the last 6 wk. The multilure trap/BioLure combination was best overall by 36% over the cylinder trap/AFF lure combination, and 57% over the multilure trap/AFF lure combination. Cylinder traps with BioLures were the least effective trap/lure combination throughout the experiment, capturing only half as many flies as cylinder traps with AFF lures. Captures with cylinder traps baited with either lure and multilure traps with BioLures were female biased. For the most part, both lures remained highly attractive and emitted detectable amounts of attractive components under hot field conditions for the duration of the 18-wk experiment. Total emission of ammonia was 4 times greater and 1-pyrroline at least 10 times greater from AFF lures compared with BioLures. Correlations of trap and lure performance with ammonia emission and weather were determined, but no conclusions were possible. Results indicate that BioLures would be the lure of choice in multilure or other McPhail-type traps and AFF lures would be superior with most sticky traps or kill stations that attract flies to outer (not enclosed) surfaces.     

Attraction of apple maggot flies, Rhagoletis pomonella (Diptera: tephritidae) of different physiological states to odour-baited traps in the presence and absence of food

Adults of apple maggot fly Rhagoletis pomonella (Walsh) of differing physiological states were marked and released in blocks of apple trees ringed by sticky red spheres. Spheres were either unbaited, baited with butyl hexanoate (synthetic host fruit odour) or baited with both butyl hexanoate and ammonium carbonate (synthetic food odour). All trap and lure treatments were compared in the presence or absence of food (bird faeces) in the blocks. Simultaneously, the response of wild immigrant flies to treatments was measured and wild females were dissected to determine state of ovary development. Large proportions (25-40%) of released mature male and female R. pomonella were recovered in blocks having traps baited with butyl hexanoate. Ammonium carbonate did not enhance trap captures and presence of food had little effect on response to synthetic odours by mature R. pomonella. Immature flies of each sex responded weakly to traps and to both types of synthetic lures and may have been arrested in blocks having food. Wild flies of both sexes exhibited a response pattern very similar to mature released flies, regardless of eggload (in the case of wild females). Results indicate that wild R. pomonella immigrating into apple orchards are primarily mature, and not hungry for protein. Behavioural control strategies are discussed in that context.     

Field evaluation of female attractants for monitoring Ceratitis capitata (Diptera: Tephritidae) under a range of climatic conditions and population levels in Western Australia

Field trials were conducted in Western Australia to compare captures of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), in a standard male-targeted trap (Lynfield trap baited with Capilure) with a synthetic, female-targeted attractant marketed as BioLure. BioLure was also compared with other fenale attractants (orange ammonia, liquid protein bait) and tested in plastic McPhail, Tephri, and Lynfield traps. The possibility of using one trap to monitor female and male C. capitata populations was also tested by combining BioLure in a trap with the male attractant, Capilure. The results of these experiments show that BioLure outperformed the female-targeted system currently used for monitoring female C. capitala (liquid protein in MePhail trap). More male C. capitata were caught in the standard male-targeted trap, but more females were caught in traps baited with BioLure irrespective of trap type, climate, host tree, or population level. Combined lure traps caught equivalent total numbers of C. capitata to the standard male-targeted trap, but fewer females were captured. Tephri traps caught more flies than McPhail traps, but McPhail traps caught equivalent proportions of females. We compared the performance in commercial orchards of the standard male-targeted trap with a female-targeted trap (McPhail with BioLure). We found that the male trap detected C. capitata more often, caught more flies, triggered the economic threshold more often (66% of the time) and was more cost effective. The male-targeted trap is recommended for use on commercial orchards if cost is limiting. However, using both male and female-targeted traps increases the chance of detecting flies and triggering the economic threshold level. The synthetic female attractant is recommended for replacement of protein hydrolysate lures and may be used in either Tephri or McPhail traps.     

Monitoring oriental fruit moth (Lepidoptera: Tortricidae) with sticky traps baited with terpinyl acetate and sex pheromone

Studies in Argentina and Chile during 2010–2011 evaluated a new trap (Ajar) for monitoring the oriental fruit moth, Grapholita molesta (Busck). The Ajar trap was delta‐shaped with a jar filled with a terpinyl acetate plus brown sugar bait attached to the bottom centre of the trap. The screened lid of the jar was inserted inside the trap, and moths were caught on a sticky insert surrounding the lid. The Ajar trap was evaluated with and without the addition of a sex pheromone lure and compared with delta traps left unbaited or baited with a sex pheromone lure and a bucket trap filled with the same liquid bait. Studies were conducted in a sex pheromone‐treated orchard in Argentina and an untreated orchard in Chile. In Chile, the Ajar trap without the sex pheromone lure caught significantly fewer males, females and total moths than the bucket trap, and fewer males and more females than the sex pheromone‐baited delta trap. Total moth catch did not differ between the Ajar trap without a sex pheromone lure and the sex pheromone‐baited trap. Adding a sex pheromone lure to the Ajar trap significantly increased total moth catches to levels not different from those in the bucket trap. However, the Ajar trap with the sex pheromone lure caught significantly more males and fewer females than the bucket trap. In Argentina, the Ajar trap with or without the addition of a sex pheromone lure caught similar numbers of both sexes and total moths as the bucket trap. The sex pheromone‐baited delta trap caught <4% of the number of moths as these three traps. The bucket trap in both studies caught significantly more non‐targets than the delta and Ajar traps. Moth catches in the Ajar trap declined significantly after 2–3 weeks when the bait was not replaced.     

Effect of trap type, trap position, time of year, and beetle density on captures of the redbay ambrosia beetle (Coleoptera: Curculionidae: Scolytinae)

The exotic redbay ambrosia beetle, Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae), and its fungal symbiont Raffaellea lauricola Harrington, Fraedrich, and Aghayeva are responsible for widespread redbay, Persea borbonia (L.) Spreng., mortality in the southern United States. Effective traps and lures are needed to monitor spread of the beetle and for early detection at ports-of-entry, so we conducted a series of experiments to find the best trap design, color, lure, and trap position for detection of X. glabratus. The best trap and lure combination was then tested at seven sites varying in beetle abundance and at one site throughout the year to see how season and beetle population affected performance. Manuka oil proved to be the most effective lure tested, particularly when considering cost and availability. Traps baited with manuka oil lures releasing 5 mg/d caught as many beetles as those baited with lures releasing 200 mg/d. Distributing manuka oil lures from the top to the bottom of eight-unit funnel traps resulted in similar numbers of X. glabratus as a single lure in the middle. Trap color had little effect on captures in sticky traps or cross-vane traps. Funnel traps caught twice as many beetles as cross-vane traps and three times as many as sticky traps but mean catch per trap was not significantly different. When comparing height, traps 1.5 m above the ground captured 85% of the beetles collected but a few were caught at each height up to 15 m. Funnel trap captures exhibited a strong linear relationship (r2 = 0.79) with X. glabratus attack density and they performed well throughout the year. Catching beetles at low densities is important to port of entry monitoring programs where early detection of infestations is essential. Our trials show that multiple funnel traps baited with a single manuka oil lure were effective for capturing X. glabratus even when no infested trees were visible in the area.     

Evaluation of trap types and food attractants for Rhagoletis cerasi (Diptera: Tephritidae)

Trapping experiments were conducted during the period of flight activity of the cherry fruit fly Rhagoletis cerasi L. in the area of Thessaloniki, northern Greece, during the years 1993-1997 to test several traps alone and in combination with different food attractants. Yellow sticky-coated visual traps were more effective than McPhail-type traps baited with different food attractants. Of the visual traps, the most effective was the yellow Rebell trap. The Rebell trap, provided with a dispenser containing a slow release formulation of ammonium acetate attached to the lower part of the trap, was found to be the most effective of all treatments tested, capturing approximately 50% more R. cerasi flies than the Rebell trap without any attractant. Ammonium carbonate dispensers did not increase the performance of Rebell traps. More mature females were captured in Rebell traps baited with or without ammonium acetate than in McPhail-type traps baited with ammonium acetate. This study demonstrates that Rebell traps baited with an ammonium acetate dispenser can provide a more effective tool for monitoring and mass trapping of R. cerasi than the currently used unbaited Rebell traps.     

Field comparison of chemical attractants and traps for Caribbean fruit fly (Diptera: Tephritidae) in Florida citrus

Field studies in citrus were conducted to compare the following as attractants for the Caribbean fruit fly, Anastrepha suspensa (Loew): torula yeast-borax; propylene glycol (10%); a two-component lure consisting of ammonium acetate and putrescine; a two-component lure consisting of ammonium bicarbonate and putrescine; and a three-component lure consisting of ammonium bicarbonate, methylamine hydrochloride, and putrescine. Various combinations of these attractants in glass McPhail, plastic McPhail-type (Multi-Lure), and sticky panel traps were investigated in two replicated studies. In one study on wild flies, the most effective and least complex trap-lure combination tested was the Multi-Lure with propylene glycol baited with ammonium acetate and putrescine. This trap-lure combination captured significantly more female and male flies than the standard glass McPhail baited with torula yeast-borax in water. All of the trap-lure combinations were female biased, with an overall average of 80.8% (SEM 1.4) flies captured being female. A second study on laboratory-reared, irradiated flies indicated no significant differences among these trap-lure combinations with respect to number of flies recaptured, although rankings based on mean number of flies recovered per trap per day supported results of the first study. The percentage of flies recaptured that were female (83.0%, SEM 0.9) was statistically the same as in the first study. Weekly percentage recovery of flies during the second study was low, possibly due to our fly release strategy. Future release/recovery studies with laboratory-reared flies would benefit from some basic research on release strategies by using different trap densities and on relating recapture rates of laboratory-reared flies (nonsterile and sterile) to capture rates of wild flies.     

Effect of trap type, trap color, trapping location, and pheromone dispenser on captures of male Palpita unionalis (Lepidoptera: Pyralidae)

Field studies were conducted to evaluate the influence of trap design, trapping location, type of pheromone dispenser, and trap color on the capture of Palpita unionalis (Hübner) males, in olive groves. The experiments were carried out in two regions, Alexandria (northern Greece) and Oropos (central Greece), where olives are cultivated. In both regions, the majority of the males (> 70% of the total) were caught from late autumn to early winter, whereas < 1% was caught during July and August. Among the trap types used, the Funnel was significantly more attractive than Delta, Pherocon 1C, and Pherocon II traps. More males were caught in traps placed at the periphery of the groves than those placed in the center. Among the four colored traps tested, white traps were the most effective. However, a significant difference in trap catches was found between white and brown traps. Traps baited with red rubber septa captured more males than those baited with the white one. The use of these parameters in monitoring and managing P. unionalis is discussed.     

A new trap and lure for Drosophila melanogaster (Diptera: Drosophilidae)

We conducted a series of nine laboratory experiments testing the response of "vinegar flies," Drosophila melanogaster Meigen (Diptera: Drosophilidae), released in bioassay chambers to experimental traps and lures. These experiments showed that an effective trap could be constructed from a clear 225-ml screw-cap jar fitted with a hollow 8-mm-diameter cylindrical cross bridge. Flies could enter the trap from either end of the cylindrical "gate" and in turn could enter the interior chamber of the trap through a cut out portion at mid-span of the cylinder. The experiments also showed that a natural-component lure could be made using a teabag containing freeze-dried banana powder, yeast, and carrageenan gum powder as a humectant. When dipped in water for 10-15 s and then placed in the bottom of a trap, the teabag provided effective attraction for at least 7 d. Captured flies were immobilized on a sticky card placed in the trap, allowing them to be easily seen. Unlike other traps that cannot be opened and have liquid lures, the cylindrical-gate trap can be reused repeatedly if the teabag and sticky card are replaced. A final two experiments showed that the prototype operational cylindrical-gate trap with a teabag lure captured 3.3 and 2.3 times more released flies, respectively, than the next best of three commercially available traps.     

Monitoring oriental fruit moth (Lepidoptera: Tortricidae) with the Ajar bait trap in orchards under mating disruption

Studies in Oregon, California, Pennsylvania and Italy evaluated the relative performance of the Ajar trap compared with several other traps for the capture of Grapholita molesta (Busck), in pome and stone fruit orchards treated with sex pheromone dispensers for mating disruption. The Ajar is a delta‐shaped trap with a screened jar filled with an aqueous terpinyl acetate plus brown sugar bait solution (TAS) that opens inside the trap and is surrounded by a sticky liner. The TAS‐baited Ajar trap was evaluated with and without the addition of a sex pheromone lure and compared with a delta trap baited with a sex pheromone lure and a bucket trap filled with the TAS bait. Although the Ajar trap had a 90% lower evaporation of the TAS bait than the bucket trap, both of them caught similar numbers in the majority of the field tests of both sexes of G. molesta. The addition of the sex pheromone lure did not increase moth catches by the TAS‐baited Ajar trap. The TAS‐baited Ajar trap caught significantly greater numbers of moths than the sex pheromone‐baited delta trap in 18 of the 20 orchards. Few hymenopterans were caught in orange TAS‐baited Ajar traps, but the catch of flies and other moths relative to the target pest remained high. Flight tunnel and field tests evaluated the effect of several screen designs on the catches of G. molesta and non‐target species. All exclusion devices significantly reduced the catch of larger moths. However, designs that did not reduce the catch of male G. molesta did not reduce the catch of muscid flies. Exclusion devices with openings <7.0 mm significantly reduced the catch of female G. molesta. The addition of (E)‐β‐farnesene, (E)‐β‐ocimene or butyl hexanoate septa lures to TAS‐baited Ajar traps significantly increased total moth catch. The addition of (E)‐β‐ocimene also significantly increased female moth catch.     

Attraction of the West Indian fruit fly to mango fruit volatiles

In this study, we investigated the attraction of West Indian fruit fly, Anastrepha obliqua (Macquart) (Diptera: Tephritidae), to volatiles of three mango [Mangifera indica L. (Anacardiaceae)] cultivars in field cage tests. The number of flies captured with Multilure traps baited with Amate mature green mangoes was significantly higher than that captured in traps baited with Coche and Ataulfo fruits. There was no significant difference between the number of flies captured in traps baited with Coche or Ataulfo mangoes. Gas chromatography‐mass spectrometry analysis of mango fruit volatiles identified 24, 22, and 19 compounds for Amate, Ataulfo, and Coche mango cultivars, respectively. A principal component analysis of the volatiles revealed that the Amate mango was more distant from the Ataulfo mango, and the latter cultivar was closer to the Coche mango. The compounds myrcene, α‐pinene, β‐selinene, and trans‐β‐ocimene were the most abundant in Amate mangoes, whereas 3‐carene, β‐selinene, terpinolene, and α‐pinene were the predominant compounds of Ataulfo cultivars. In the Coche mango, the predominant compounds were 3‐carene, β‐selinene, terpinolene, and limonene. Traps baited with a blend of myrcene, α‐pinene, and trans‐β‐ocimene captured more A. obliqua females and males than control traps. Flies were more attracted to the Super Q volatile extracts of Amate mango than to the three‐component blend formulated in a ratio of 1:1:1. However, there was no significant difference between the number of flies caught by traps baited with Amate mango extracts and that caught by traps baited with the three‐blend component when this was formulated according to the relative proportions in the mango extracts. Traps baited with myrcene, the major component, caught fewer flies than traps baited with Amate mango extracts.     

Short-range dispersal of recently emerged males and females of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) monitored by sticky sphere traps baited with protein and Lynfield traps baited with cue-lure

Abstract  Dispersal of immature male and female Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), was assessed over a period of 1 week from a single release point on three separate occasions using an array of Lynfield traps baited with cue-lure and odouriferous yellow or black sticky spheres baited with food lure (protein autolysate). Lynfield traps recaptured males; yellow or black spheres recaptured both sexes in approximately equal proportions, although at a much lower rate. As a percentage of the recapture rate for males by Lynfield traps, the mean recapture rate for yellow spheres ranged from 1.0% to 7.5% for males and 0.7% to 4.0% for females, whereas the recapture rates for black spheres ranged from 0.4% to 3.6% and 0.6% to 1.8%, respectively. The rate of recapture of sterile male flies was greater than that of unsterilised flies; this may have been due to a faster maturation rate in sterile males or because a greater proportion of them remained within the trap array rather than dispersing. There was no significant trend in recapture rate with distance from the release point to the edge of the array (88 m), except in the case of females on sticky traps where no trend was detected between 19 and 88 m. These results lend support to assumptions made about the distribution of males and females with respect to the minimum breeding density of fruit fly propagules invading a fly-free zone, and the method chosen to distribute sterile B. tryoni for the sterile insect technique.