Capture Of Flies Research Articles

Seasonal variation of the capture and field distribution of sterile Anastrepha ludens in Tamaulipas, Mexico

AbstractAnastrepha ludens (Loew) (Diptera: Tephritidae) is one of the most important citrus pest in Mexico. The sterile insect technique (SIT) is used against pest populations of fruit flies for suppression, eradication, containment and prevention to reduce damages in fruit‐growing areas. In this study, we analyzed the seasonal variation of captures and field distribution of sterile A. ludens released in different seasons of the year in north‐eastern Mexico. Chilled releases were conducted by air at constant densities per ha on a citrus area for a period of 32 weeks that included the coldest and warmest seasons that is winter, spring and summer. Multilure traps baited with torula yeast pellets were used to capture sterile flies. Fly capture data were compared over the three seasons and correlated with climate. The lowest number of captures of the sterile insect occurred in the summer and the highest in winter and spring. High and low temperatures were negatively correlated with fly captures. Field distribution was also negatively correlated with high temperatures in summer, but no relationships were observed in winter and spring. No relationships were observed between rainfall with capture and field distribution of sterile flies. These results indicate that summer is a season involving agro‐ecological and environmental constraints for the capture and field distribution of sterile flies. This study may be useful for enhancing release strategies and optimizing economic resources in north‐eastern Mexico. Further research on the behaviour of sterile flies under stressful environments is suggested.

Capture of Melon Flies and Oriental Fruit Flies (Diptera: Tephritidae) in Traps Baited with Torula Yeast-Borax or CeraTrap in Hawaii

Summary Food baits are a key component in trapping programs to detect infestations of pest species of tephritid fruit flies (Diptera: Tephritidae). Traditionally, a torula yeast-borax slurry has been used most frequently, but the recently developed food bait CeraTrap, consisting of hydrolyzed animal protein, has proven more attractive to certain tephritids. This study compared field captures of melon flies, Zeugodacus cucurbitae (Coquillett), and oriental fruit flies, Bactrocera dorsalis (Hendel), in traps baited with torula yeast-borax or CeraTrap in an agricultural setting in Hawaii. Data show that melon flies were captured in significantly greater numbers in traps baited with torula yeast-borax than CeraTrap, while no difference in captures was noted for the oriental fruit fly between traps baited with the 2 food types. Sumario Los cebos alimenticios son un componente clave en los programas de captura para detectar infestaciones de especies de moscas de la fruta tefritidas (Diptera: Tephritidae). Tradicionalmente, se ha utilizado con mayor frecuencia una suspension de torula levadura-borax, pero el cebo alimenticio recientemente desarrollado CeraTrap, que consiste en proteina animal hidrolizada, ha demostrado ser mas atractivo para ciertos tefritidos. Este estudio comparo capturas de campo de la mosca de melon, Zeugodacus cucurbitae (Coquillett) y la mosca de la fruta oriental, Bactrocera dorsalis (Hendel), en trampas cebadas con torula levadura-borax o CeraTrap en un entorno agricola en Hawaii. Los datos muestran que las moscas de melon fueron capturadas en numeros significativamente mayores en trampas cebadas con torula levaduraborax que CeraTrap, mientras que no se observaron diferencias en las capturas para la mosca de la fruta oriental entre las trampas cebadas con los 2 tipos de alimentos. View this article in BioOne

Capture of melon flies, Zeugodacus cucurbitae (Diptera: Tephritidae), in a food-baited Multilure trap: Influence of distance, diet, and sex

Many countries operate trapping programs to detect invasions of pestiferous fruit fly species (Diptera: Tephritidae). Surveillance relies heavily on traps baited with male lures, which, while highly attractive, have limited effectiveness, because (i) they are sex-specific and (ii) males of some species do not respond to the lures currently in use. For these reasons, detection programs also include food-baited traps that are neither sex- nor species-specific. Compared to male lure-baited traps, however, few studies have measured the attractiveness of food-based traps. The present study describes a mark-release-recapture study conducted in a fruit orchard in Hawaii that measured the attractiveness of a liquid protein hydrolysate-based (torula yeast/borax slurry) trap to adults of the melon fly Zeugodacus cucurbitae (Coquillett). Multiple release points were used at varying distances from a single, central trap to generate estimates of distance-dependent capture probabilities. The potential influences of sex and pre-release diet on capture probability were also examined. Flies were released at 14 d of age and were maintained on one of four dietary regimes that offered a protein hydrolysate-rich diet for varying intervals (i.e., 0, 3, 7, or 14 d, respectively). Recapture rates were similar between the sexes and over both sexes and all diets averaged 3.6%, 3.2%, and 0.6% for release distances of 10, 25, and 50 m, respectively. Pre-release diet had a significant effect on recapture probability for releases at 10 and 25 m: flies fed sugar only or protein hydrolysate-rich diet for only 3 d were captured more frequently than flies that had longer access to yeast extract prior to release.

Improved capture of stable flies (Diptera: Muscidae) by placement of knight stick sticky fly traps protected by electric fence inside animal exhibit yards at the Smithsonian's National Zoological Park.

Stable flies are noxious blood-feeding pests of exotic animals at zoological parks, inflicting painful bites, and causing discomfort to animals. Stable fly management is difficult because of the flies' tendency to remain on the host animals only when feeding. Non-toxic traps can be efficient but traps placed around exhibit perimeters captured fewer-than-expected numbers of flies. By surrounding traps with square electric fence enclosures, traps could be placed in the exhibits with the host animals and compared with an equal number of traps placed along perimeter fences. During a 21-week study, traps inside exhibits captured 5× more stable flies than traps placed along exhibit perimeters. Traps inside exhibits tended to show more fluctuations in fly populations than traps along perimeters. The increased numbers of flies captured using this technique should provide relief from this pestiferous fly and greatly improve animal health and welfare. We believe this to be the first study where traps were used to capture stable flies in exhibit yards at a zoological park.

The Dynamics of Tsetse Flies Around the Mbam and Djerem National Park

A capture of tsetse flies was done between November 2014 and July 2016 in three localities around the Mbam and Djerem National Park. The biconic traps were used for the captures in Yoko, Mbakaou and Betare-Oya during 5 days. These traps permitted to capture 709 tsetse flies belonging to four species: Glossina fuscipes fuscipes (54.16%), Glossina fusca congolensis (29.34%), Glossina palpalis spp (7.19%) and Glossina calliginea (9.31%). The season did not influence the abundance of tsetse flies. In general, no significant influence was observed between the localities. Specifically, the Glossina palpalis spp species presented a significant difference in its distribution between the localities of Betare-Oya and Yoko (P=0.048). The Glossina calliginea species was also differently distributed between the traps close to a path in T4 enlightened area and the traps close to a path to T3 shade (P=0.042), presenting a direct link between the number of tsetse flies and the presence of cattle.

Comparison of local fruit flies attractant with imported attractants (Methyl Eugenol & Cue Lure) in guava, peach and bitter gourd orchards in Khyber Pakhtunkhwa

Studies were carried out for comparison of local fruit fly attractant with imported attractants, in Khyber Pakhtunkhwa during 2010 and 2011. The trials were conducted in three different localities in different orchards i.e Swat (Peach orchards), Charsada (Bitter gourd) and Kohat (Guava orchards). The experiment was consisted of different attractants i.e. Methyl Eugenol (M.E), Cue Lure (C.L) and protein based product locally developed (PPr-Product) for efficient management of Tephritid species in the field in modified McPhill traps. The trials were laid out in randomized complete block design replicated three times. Findings showed that significant variation was recorded for the captured of fruit flies among different attractants and observational dates in guava, peach and bitter gourd orchards. Methyl eugenol trapped more fruit flies as compared PPr-Product and C.L trap in Guava and Peach orchards whereas higher number of fruit flies was captured by PPr-Product as compared to both C.L and M.E traps in bitter gourd orchards. Higher capture of B. zonata and B. dorsalis in guava and peach orchards was recorded by M.E whereas C.L attracted more B. cucuribitae as compared to M.E traps for Peach, Guava and Bitter gourd orchards. More numbers of B. zonata and B. dorsalis captured by PPr-Product in Bitter gourd. The highest trapped fruit flies in Peach orchards were recorded in mid September. For Bitter gourd orchards, the fruit fly capture increased from March to 1 st September and the highest peak of its species were in September. For Guava orchards, the fruit fly trapped population and its species increased till 1 st July and then decreased thereafter. The PPr-Product traps were found more effective against all three types of female adults flies whereas M.E traps captured more male adults of B. Zonata and B. dorsalis while C.L captured more male adults of B. cucurbitae in Peach, Bitter gourd and Guava orchards. The highest capture of female adults of the three species was obtained by PPr-Product in Guava and Peach orchards.

Phenology of spotted wing drosophila in the San Joaquin Valley varies by season, crop and nearby vegetation

The spotted wing drosophila, first detected in California in 2008, has become a major insect pest in caneberries and sweet cherries, causing commercial crop losses. Managing it is challenging because it has many other hosts, including riparian and backyard fruit plantings, and it increases rapidly, with generations overlapping one another. In our study we monitored trap captures in two parts of the San Joaquin Valley, within sweet cherry orchards and in nearby locations. Captures of adult flies showed two main periods of activity — spring and fall — and low captures in the winter (except for citrus and evergreen riparian areas) and summer. On many occasions during the year, trap captures were higher outside of the cherry orchards than within them. Additionally, early in the season, when decisions about control programs are being made, the sex ratio of captured flies in cherries was strongly female-biased. The results suggest that during the weeks leading up to harvest growers should experiment by placing traps in different environments surrounding their orchards to determine SWD activity and potential pest pressure locally, and monitor for both male and female flies.

<b>Hole diameters in pet bottles used for fruit fly capture

Two experiments were conducted during the period from 31 January to 6 March 2012 in Santa Maria, Rio Grande do Sul State, Brazil to determine the efficiency of different hole diameters in PET trap bottles on pests in guava and persimmon orchards. In a randomised block design in a factorial scheme, we assessed the average number adults of Anastrepha fraterculus, Ceratitis capitata (Diptera: Tephitidae) and Zaprionus indianus (Diptera: Drosophilidae) infruits thatemerged in two situations (in the plant and on the soil); we also assessed the number of captured adults in trap bottlesunder two conditions, different hole diameters and different days after placement of the attractive solution. Smaller diameter sizescaptured more A. fraterculus, C. capitata and Z. indianusadults. The 1.0 cm diameter was the most efficient hole size in reducing the adult emergence of Tephritidae to Z. indianus, whereas the smallest diameter hole sizes, 0.6 and 0.8 cm, showed the highest efficiencies in controlling adult emergence in persimmon fruit and guava fruit.

Residual attractiveness of various bait spray solutions to Bactrocera oleae

Effective insecticidal bait formulations ought to induce high levels of attraction and stimulate flies to ingest a lethal dose of the toxicant upon feeding or contact. The key to the effectiveness of such baits is the amount of time that the bait remains attractive to adult flies after spray application. Solutions of trophical attractants of Bactrocera oleae (two formulations of hydrolysed proteins at 55% and 75% w/w) mixed with various insecticides (alpha-cypermethrin, lambda-cyhalothrin and dimethoate) and a spinosad solution, applied either in McPhail traps or sprayed in olive foliage (except lambda-cyhalothrin), were tested for their attractiveness over time during two periods in successive summers. The results indicated that among all bait spraying solutions tested against B. oleae, the highest catches were recorded with both protein solutions of alpha-cypermethrin; its capture rate ranged from 7.6 to 10.5 olive fruit flies/trap/solution age (seven measurements were made when the trap solution was changed at 3, 7, 10, 14, 17, 20 and 24 days after its preparation). A three-day-old solution of any protein mixed with alpha-cypermethrin was significantly more attractive to olive fruit flies (at least three times) compared with the solutions at other ages, as indicated by the capture of flies in the McPhail traps. No differences were observed among solution ages for dimethoate solutions or spinosad solutions (less than 6 olive fruit flies/trap/week). When olive foliage was sprayed with the solutions under field conditions, they attracted approximately 0.3–1.5 adults per day for a 10-day period. The highest number of flies was recorded on both proteins combined with or without alpha-cypermethrin solution, as indicated by the catches on sticky transparent panels. Finally, changes in the pH values of the aforementioned solutions over time were associated with increased fly catches.

A simple isothermal DNA amplification method to screen black flies for Onchocerca volvulus infection.

Onchocerciasis is a debilitating neglected tropical disease caused by infection with the filarial parasite Onchocerca volvulus. Adult worms live in subcutaneous tissues and produce large numbers of microfilariae that migrate to the skin and eyes. The disease is spread by black flies of the genus Simulium following ingestion of microfilariae that develop into infective stage larvae in the insect. Currently, transmission is monitored by capture and dissection of black flies and microscopic examination of parasites, or using the polymerase chain reaction to determine the presence of parasite DNA in pools of black flies. In this study we identified a new DNA biomarker, encoding O. volvulus glutathione S-transferase 1a (OvGST1a), to detect O. volvulus infection in vector black flies. We developed an OvGST1a-based loop-mediated isothermal amplification (LAMP) assay where amplification of specific target DNA is detectable using turbidity or by a hydroxy naphthol blue color change. The results indicated that the assay is sensitive and rapid, capable of detecting DNA equivalent to less than one microfilaria within 60 minutes. The test is highly specific for the human parasite, as no cross-reaction was detected using DNA from the closely related and sympatric cattle parasite Onchocerca ochengi. The test has the potential to be developed further as a field tool for use in the surveillance of transmission before and after implementation of mass drug administration programs for onchocerciasis.

Reduction of olive fruit fly damage by early harvesting and impact on oil quality parameters

Olive fly population was monitored weekly on two olive cultivars (Buža and Istarska bjelica), from June until mid October, in Rovinj and Livade (Istria, Croatia). The number of eggs, larvae, and pupae was established and the total and active infestation was calculated. The fruit infestations for early and for late harvesting were obtained based on the calculated regression equation. For the prediction of the changes in the oil quality parameters linear regression slopes, obtained by Koprivnjak et al., were used. We established a strong positive correlation between DD accumulation and cumulative capture of flies, as well as with the total and active fruit infestations. According to obtained results it can be stated that I. bjelica is less sensitive to decrease in total phenols amount, to increase in free fatty acids mass ratio and to increase in peroxide values comparing to Buža. Moreover, the differences in investigated parameters between earlier and late harvesting dates in I. bjelica are lower due to lower infestation predicted for both harvesting dates and due to lower sensitivity to the changes in quality parameters. Therefore, early harvesting date as a model for preventing fruit damage and as a model for preventing negative change in oil quality parameters is a valid tool. However, the effectiveness of this model could also depend on the characteristics of olive cultivar.Practical applications: Understanding the factors that affect the olive fly attack is the basis of scientific and practical interest in the production of olives and olive oil. Research of monitoring methods allows reliable forecasting and determining protection measures. Knowledge about this topic could contribute to the reduction of insecticides use and to the improvement of quality and food safety concept in olive oil production.Damaged olive fruits are proved to directly affect the quantitative and qualitative properties of olive oils. The most important fruit damage is caused by the olive fly (Bactrocera oleae Gmelin).

Seasonal Distributions of the Western Cherry Fruit Fly (Diptera: Tephritidae) Among Host and Nonhost Fruit Trees

Seasonal distributions of the western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), in sweet cherry ( Prunus avium (L.) L.) (major host), black hawthorn (occasional developmental host) ( Crataegus douglasii Lindley), and other trees were determined in a ponderosa pine ecosystem in Washington state, USA. The hypothesis that most fly dispersal from cherry trees occurs after fruit senesce or drop was tested, with emphasis on movement to black hawthorn trees. Sweet cherry fruit developed earlier than black hawthorn, bitter cherry (common host), choke cherry, and apple fruit. Flies were usually captured first in sweet cherry trees but were caught in bitter cherry and other trees throughout the season. Peak fly capture periods in sweet cherry began around the same time or slightly earlier than in other trees. However, peak fly capture periods in black hawthorn and other nonsweet cherry trees continued after peak periods in sweet cherry ended, or relative fly numbers within sweet cherry declined more quickly than those within other trees. Larvae were reared from sweet and bitter cherry but not black hawthorn fruit. Results provide partial support for the hypothesis in that although R. indifferens commonly disperses from sweet cherry trees with fruit, it could disperse more, or more flies are retained in nonsweet cherry trees after than before sweet cherries drop. This could allow opportunities for the flies to use other fruit for larval development. Although R . indifferens infestation in black hawthorn was not detected, early season fly dispersal to this and other trees and fly presence in bitter cherry could make fly management in sweet cherry difficult.

Fruit flies (Diptera, Tephritidae) and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil

Fruit flies (Diptera, Tephritidae) and their parasitoids on cultivated and wild hosts in the Cerrado-Pantanal ecotone in Mato Grosso do Sul, Brazil. Information on frugivorous flies in cultivated or wild host plants and their parasitoids in the Cerrado-Pantanal ecotone in Aquidauana, Mato Grosso do Sul is presented and discussed. Fruit fly samples were collected weekly in specific fruit trees, and McPhail® traps were installed in the same trees for a period of two years. The fruit flies infested ripe and unripe fruits of Averrhoa carambola L., Schoepfia sp., Psidium guajava L. and Pouteria torta (Mart.) Radlk and mature fruits of Anacardium occidentale L. and Inga laurina (Sw.) Willd. Nineteen fruit fly species were obtained with the combination of sampling methods (collecting fruits and trapping), nine of them obtained with both methods, five found only in fruits and five only in traps. This is the first record of Anastrepha striata Schiner in a species of Sapotaceae, as well as for A. castanea Norrbom and A. daciformes Bezzi in Schoepfia sp. (Olacaceae), and for A. distincta Greene in fruits of P. guajava in the state of Mato Grosso do Sul. Fruit collections simultaneously associated with capture of fruit flies by McPhail traps in the same host plants are essential to understand the diversity of fruit flies and their relationship with hosts and parasitoids. Species of Braconidae and Pteromalidae were recovered, where Doryctobracon areolatus (Szépligeti) was the most abundant parasitoid in larvae of tephritids infesting both cultivated and wild host fruits.

Capture ofAnastrepha suspensaand Sterile MaleCeratitis capitata(Diptera: Tephritidae) in Multilure Traps Versus Phase 4 Traps

Field trials were conducted in south Florida to compare capture of wild Caribbean fruit flies, Anastrepha suspensa (Loew), and sterile male Mediterranean fruit flies, Ceratitis capitata (Wiedemann), in Multilure traps, which are McPhail-type traps that use an aqueous solution to retain attracted flies, and Phase 4 traps, which are open-bottom dry traps that use a sticky insert to retain attracted flies. One study was conducted in a guava orchard and compared capture of A. suspensa in both trap types baited with ammonium acetate plus putrescine alone (two-component BioLure) or in combination with trimethylamine (three-component BioLure). A second study compared captures of A. suspensa and sterile male C. capitata in traps baited with three-component BioLure in an urban area near the end of the eradication program for a C. capitata outbreak. In both studies, captures were higher in the Multilure traps than the Phase 4 traps baited with the same lure, with catches ranging from 5:1 for sterile C. capitata, and ∼10:1 to ∼100:1 for wild A. suspensa. Large scale area-wide deployment of fruit fly detection traps is costly in both materials and in the time and effort required in routine servicing. Although a simpler and cheaper trap such as the Phase 4 trap would be a welcome relief to any large scale area-wide detection programs, it must perform effectively. This is the first report of tests of fruit fly capture in Phase 4 traps conducted under of south Florida conditions.

Hidrogenionic potential (pH) of the attractant, trap density and control threshold for Ceratitis capitata (DIPTERA: TEPHRITIDAE) on Hamlin oranges in São Paulo central region, Brazil

This study evaluated the effect of initial pH values of 4.5, 6.5 and 8.5 of the attractant (protein bait) Milhocina® and borax (sodium borate) in the field, on the capture of fruit flies in McPhail traps, using 1, 2, 4 and 8 traps per hectare, in order to estimate control thresholds in a Hamlin orange grove in the central region of the state of São Paulo. The most abundant fruit fly species was Ceratitis capitata, comprising almost 99% of the fruit flies captured, of which 80% were females. The largest captures of C. capitata were found in traps baited with Milhocina® and borax at pH 8.5. Captures per trap for the four densities were similar, indicating that the population can be estimated with one trap per hectare in areas with high populations. It was found positive relationships between captures of C. capitata and the number of Hamlin oranges damaged, 2 and 3 weeks after capture. It was obtained equations that correlate captures and damage levels which can be used to estimate control thresholds. The average loss caused in Hamlin orange fruits by C. capitata was 2.5 tons per hectare or 7.5% of production.

Factors affecting the efficacy of a vinegar trap for Drosophila suzikii (Diptera; Drosophilidae)

AbstractDrosophila suzukii, Matsumura, is a relatively new pest in the United States attacking a variety of fruit crops. Studies were conducted to develop a standardized, economical trap for monitoring. Laboratory bioassays found that flies were attracted to dark colours ranging from red to black. Similarly, fly catches in 237‐ml plastic ‘spice’ jars with ten 0.48‐cm holes and baited with apple cider vinegar were significantly higher in jars with red or black than white caps. The use of an alternating set of three, horizontal red, black and red bands (‘Zorro’ trap) significantly increased fly catches compared with the use of all‐red or all‐black strips. This increase was associated with a significantly higher proportion of flies first landing on the side near the openings of the trap instead of on the cap with the ‘Zorro’ trap compared with the other traps. Laboratory data were used to develop a predictive model to define total fly capture as a function of trap colour/colour pattern, cumulative area of entry holes and the length of the trapping portion of the trap. Total fly catches by the ‘Zorro’ trap were compared with other red and clear plastic traps in five field trials conducted in several cultivated and uncultivated sites. Comparisons included a commercial red‐capped 200‐ml trap with two 0.63‐cm holes, an all‐red spice jar with ten 0.48‐cm holes and clear and red 473‐ml and clear 946‐ml plastic cups with six or ten 0.48‐ or 0.63‐cm holes. The model was successfully validated, suggesting that performance of cup traps can be predicted based on a few characteristics. The current ‘Zorro’ trap did not catch most of the flies among trap designs, but showed some advantages, including the durability and potential to recycle the plastic, small size, commercial availability and its greater selectivity for D. suzukii than the other traps tested.

Seasonal Flight, Optimal Timing and Efficacy of Selected Insecticides for Cabbage Maggot (Delia radicum L., Diptera: Anthomyiidae) Control.

In order to describe seasonal flight activity of the cabbage maggot Delia radicum (L.) adults in relation to Julian days (JD), degree-day accumulations (DDA) and precipitation, flight dynamics were followed weekly with the use of yellow sticky traps (YST). Climatic data were collected and DDA were calculated using the lower developmental threshold of 4.3 °C. The efficacy of four insecticides applied either as standard foliar treatment or through dipping the seedlings before transplanting was determined. Seasonal flight activity during the cultivation season of a mid-early variety of white cabbage was correlated with DDA and JD and was characterized by having two peaks. The first peak occurred between 119 ± 7.5 JD and 125.5 ± 8 JD when DDA was 471.35 ± 74.97 °C. The second occurred between 172.8 ± 6.1 JD and 179.3 ± 6.7 JD when DDA was 1,217.28 ± 96.12 °C. The DDA, cumulative capture of flies and JD are suitable for predicting the timing of insecticide application. Spraying with insecticides should be applied when the cumulative capture of flies reaches 100 flies/YST and when DDA reaches 400 °C. If only one parameter reaches the threshold, additional visual surveys should be employed to establish the level of infestation. Insecticides were able to ensure only partial control. In the future, alternative control tactics which employ seed treatments and nonpesticide measures should be investigated in Croatia.

Capture of Bactrocera fruit flies in traps baited with liquid versus solid formulations of male lures in Malaysia

Approximately 70 species of Bactrocera fruit flies (Diptera: Tephritidae) are polyphagous economic pests that attack many important agricultural crops. Several of these Bactrocera species are also highly invasive, and many countries operate continuous, large-scale trapping programs to detect incipient infestations. Detection programs rely heavily on traps baited with male lures, with males of some species responding to raspberry ketone (RK; or its synthetic analogue cue-lure [CL]) and males of other species responding to methyl eugenol (ME). These lures (plus naled, an insecticide) are currently applied as liquids, although this procedure is time-consuming and may expose workers to health risks. Recent field tests, conducted largely in Hawaii, have shown that traps baited with a solid formulation (termed a wafer) that contains both RK and ME (plus dichlorvos, an insecticide) capture as many or more B. dorsalis (Hendel) and B. cucurbitae (Coquillett) males as traps baited with the standard liquid lures. While these results are promising, a more complete evaluation of the solid formulation requires testing in a region with a diverse assemblage of Bactrocera species, since interspecific variation in male response to lures has been reported. The objective of the present investigation was to assess the relative effectiveness of liquid versus solid formulations of male lures in Malaysia, a country known to harbor a large assemblage of Bactrocera species. Based on a 12-week sampling period, we found that, contrary to the Hawaiian results, traps baited with the wafer captured significantly fewer males than traps baited with liquid lures for all five ME-responding taxa analyzed and for one of the three RK/CL-responding species analyzed. Possible explanations for the discrepancy between these and earlier findings are offered.

Comparison of Three Carbon Dioxide Sources on Phlebotomine Sand Fly Capture in Egypt

Lighted Centers for Disease Control and Prevention (CDC) light traps were baited with carbon dioxide (CO2) produced from three different sources to compare the efficacy of each in collecting phlebotomine sand flies in Bahrif village, Aswan Governorate, Egypt. Treatments consisted of compressed CO2 gas released at a rate of 250 ml/min, 1.5 kg of dry ice (replaced daily) sublimating from an insulated plastic container, CO2 gas produced from a prototype FASTGAS (FG) CO2 generator system (APTIV Inc., Portland, OR), and a CDC light trap without a CO2 source. Carbon dioxide was released above each treatment trap's catch opening. Traps were placed in a 4 x 4 Latin square designed study with three replications completed after four consecutive nights in August 2007. During the study, 1,842 phlebotomine sand flies were collected from two genera and five species. Traps collected 1,739 (94.4%) Phlebotomus papatasi (Scopoli), 19 (1.0%) Phlebotomus sergenti, 64 (3.5%) Sergentomyia schwetzi, 16 (0.9%) Sergentomyia palestinensis, and four (0.2%) Sergentomyia tiberiadis. Overall treatment results were dry ice (541) > FG (504) > compressed gas (454) > no CO2 (343). Total catches of P. papatasi were not significantly different between treatments, although CO2-baited traps collected 23-34% more sand flies than the unbaited (control) trap. Results indicate that the traps baited with a prototype CO2 generator were as attractive as traps supplied with CO2 sources traditionally used in sand fly surveillance efforts. Field-deployable CO2 generators are particularly advantageous in remote areas where dry ice or compressed gas is difficult to obtain.

Capture of Bactrocera fruit flies (Diptera: Tephritidae) in traps baited with liquid versus solid formulations of male lures

Bactrocera dorsalis (Hendel) and B. cucurbitae (Coquillett) (Diptera: Tephritidae) are important agricultural pests of the Pacific region. Detection and control of these species rely largely on traps baited with male-specific attractants (parapheromones), namely methyl eugenol for B. dorsalis and cue lure for B. cucurbitae. Presently, these lures (plus naled, an insecticide) are applied in liquid form, although this procedure is time-consuming, and naled as well as methyl eugenol may pose human health risks. Recently, a solid formulation (termed a wafer) has been developed that contains both male lures (plus DDVP, an insecticide), and here we present data from field tests in California and Hawaii that compare the effectiveness of liquid versus solid formulations of the lures in capturing marked, released males of these two Bactrocera species. For both species and in both California and Hawaii, traps baited with the solid formulation of the male lure captured similar or significantly more released flies than the liquid formulation for both fresh and aged baits. Traps in Hawaii also captured wild (unmarked) males of both B. dorsalis and B. cucurbitae, and the results obtained for wild flies were similar to those recorded for released flies for both species. Collectively, the results presented suggest that the solid dispenser of the male lures constitutes a reliable substitute for the liquid formulation in detecting incipient Bactrocera outbreaks.