Explore the vast range of titles available.

Detection of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), relies heavily on traps baited with trimedlure, a male-specific attractant. Originally used as a liquid, trimedlure is now dispensed from solid polymeric plugs (2 g active ingredient) that reduce volatilization and increase the effective longevity of the lure. Even so, plugs are attractive over a relatively short interval, and guidelines suggest that trimedlure plugs be replaced every 6 wk. The present study had 2 goals. First, at periodic intervals up to 10 or 12 wk, we evaluated the performance of plugs containing 4 g of trimedlure (i.e., twice the standard amount) to determine whether the increased loading resulted in an increased period of effective attractiveness. Second, we examined the relationship between trap captures and temporal changes in the residual amount and release rate of trimedlure. In 2 of the 3 field trials conducted in Hawaii and Florida, 4 g plugs weathered for as long as 8 wk, but not for 10 or 12 wk, performed as well as fresh liquid trimedlure applied to cotton wicks. In the other trial, plugs weathered for as long as 12 wk were as effective as fresh liquid. Chemical analyses revealed that the plugs were effective until the residual amount of trimedlure decreased below approximately 1.4 g and the release rate dropped below approximately 2.0 mg per h. The potential usefulness of 4 g trimedlure plugs in large-scale detection programs is discussed considering these findings. La detección de la mosca mediterránea de la fruta (moscamed), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), depende en gran medida de trampas cebadas con trimedlure, un atrayente específico para machos. Utilizado originalmente como líquido, el trimedlure ahora se dispensa a partir de tapones poliméricos sólidos (2 g de ingrediente activo) que reducen la volatilización y aumentan la longevidad efectiva del señuelo. Aun así, los tapones son atractivos durante un intervalo relativamente corto, y las pautas sugieren que los tapones trimedlure se reemplacen cada 6 semanas. El presente estudio tuvo 2 objetivos. Primero, a intervalos periódicos de hasta 10 o 12 semanas, evaluamos el desempeño de los tapones que contenían 4 g de trimedlure (es decir, el doble de la cantidad estándar) para determinar si el aumento de la carga resultó en un mayor período de atractivo efectivo. En segundo lugar, examinamos la relación entre las capturas de trampas y los cambios temporales en la cantidad residual y la tasa de liberación de trimedlure. En 2 de los 3 ensayos de campo realizados en Hawái y Florida, los tapones de 4 g resistidos durante 8 semanas, pero no durante 10 o 12 semanas, funcionaron tan bien como trimedlure líquido fresco aplicado a mechas de algodón. En el otro ensayo, los tapones expuestos a la intemperie durante 12 semanas fueron tan efectivos como los líquidos frescos. Los análisis químicos revelaron que los tapones fueron efectivos hasta que la cantidad residual de trimedlure disminuyó por debajo de aproximadamente 1,4 g y con la tasa de liberación cayendo por debajo de aproximadamente 2,0 mg por hora. La utilidad potencial de los tapones de trimedlure de 4 g en los programas de detección a gran escala se discute considerando estos hallazgos.

Emerging pests are increasingly threatening fruit orchard health across the Mediterranean area. Tephritidae, representing serious threats for Europe, are numerous, and the fruit flies Bactrocera zonata and those belonging to Bactrocera dorsalis complex are among the most alarming species. These species are highly polyphagous and B. zonata has already spread to some Mediterranean countries. Due to these ongoing threats, in the Campania Region (southern Italy), a survey with traps and infested fruits analysis was performed with the aim of detecting the presence of species of Bactrocera dorsalis complex. In two mixed fruit-trees fields, some adults belonging to a species of Bactrocera were captured in traps baited with the highly attractive male lure (methyl eugenol). They were distinguished from similar-looking Bactrocera spp. by morphological and molecular comparative analyses. Considering the existing morphological keys, specimens were tentatively identified as B. dorsalis but molecular characterization with COI split them into two clades. Some specimens were grouped with B. dorsalis similar to B. kandiensis and B. kandiensis and others in a clade including B. dorsalis and B. invadens (syn. B. dorsalis). ITS1 sequences instead confirmed morphological identification. The integrative approach allowed identifying all the specimens collected as belonging to the B. dorsalis complex. This finding represents the first field interception in Europe of a member of one of the most dangerous groups of fruit flies.

As a vital pest control strategy, trapping plays an important role in the system of monitoring, catching and killing fruit flies. Cuelure (4-(4-acetoxyphenyl)-2-butanone, CL) is a male lure that attracts Zeugodacus tau and also stimulates feeding in this species. In this study, the attraction of Z. tau to CL and its subsequent feeding behavior were investigated. Under the significant influence of age and time of day, the attraction of CL to Z. tau was found to be optimal when flies were 14 days old, and the number of flies trapped increased with trapping duration. It was determined that consumption can improve the mating success and female adult fertility of Z. tau. After the observation period, the mating success rate of flies that ingested CL was significantly higher than that of the control group and was maintained at a higher level. It was found that parental consumption of CL could accelerate the development of eggs and larvae, resulting in increased pupation and emergence rates. The results of this study will further clarify the dynamic relationship between pest and lure, and provide a research basis for navigating the integrated management of Z. tau in the field.

Melon fly, Zeugodacus cucurbitae (Coquillett), is a serious pest of tropical horticulture, causing damage to cucurbits, other fruiting vegetables, and certain tree fruits. The deployment of male lures comprises an important component of several detection and control strategies for this pest, with the main male attractant currently in use being cuelure (CL). A novel fluorinated analog of CL, raspberry ketone trifluoroacetate (RKTA), has been developed for the control of Bactrocera tryoni, a related pest; here, we test this compound for attraction to Z. cucurbitae. In outdoor screen cage testing, observations showed both more flies on filter papers, and a higher percentage of flies feeding, on papers treated with RKTA than on those with CL or melolure (ML). Field trapping with both yellow sticky traps and bucket traps found that RKTA captured more flies during the first 6 h of trapping than CL, while trap captures in the subsequent 18 h did not differ between the two lures. When comparing combined 24 h trap captures, yellow sticky traps containing RKTA captured more flies than those with CL, while bucket trap captures did not vary by lure. Analysis of lures weathered on filter paper found that nearly all applied RKTA hydrolyzed to RK within 6 h. Fine-scale melon fly behaviors digitally recorded in the field showed median resting distances from the lure of responding flies were shorter for RKTA than for CL. This study demonstrates the inherent attractiveness of RKTA while also highlighting the instability of this compound due to hydrolysis.

Abstract Invasive fruit flies (Diptera: Tephritidae) pose a serious threat to the production and export of many commercially important fruits and vegetables. Detection of the agricultural pests Bactrocera dorsalis (Hendel) and Zeugodacus cucurbitae (Coquillett) relies heavily on traps baited with male-specific attractants. For B. dorsalis, traps are typically baited with liquid methyl eugenol (ME), and for Z. cucurbitae, traps are baited with liquid cue-lure (CL). Operating large-scale trapping networks is costly, consequently, there is much interest in identifying ways to maintain network sensitivity while reducing costs. One cost-cutting approach is the possibility of combining different male lures in the same dispenser, thus reducing the number of traps requiring servicing. The chief objective of this study was to compare captures of B. dorsalis and Z. cucurbitae males in Jackson traps baited with polymeric wafers impregnated with both ME and raspberry ketone (RK, a hydrolyzed form of CL) versus traps baited with liquid ME or CL freshly applied to cotton wicks. Captures were measured when the ME/RK wafers had been weathered for 12, 18, or 24 wk. Captures of B. dorsalis and Z. cucurbitae males were similar between fresh lure and weathered wafers over all trapping periods, with a single exception apparently due to the lessened potency of the associated killing agent. The residual amount and release rate of ME and RK from the wafers were also measured to examine possible relationships between wafer chemistry and trap catch. The possible implications of the present results to area-wide trapping programs are discussed.

Detection of invasive populations of Bactrocera dorsalis relies on traps baited with the male-specific attractant methyl eugenol. Standard protocol involves applying 5 mL of liquid methyl eugenol (1% naled) to a cotton wick, which is then placed inside a Jackson trap. Because of the lure's high volatility, the lure is replaced every 6 wk. Prolonging the lure's longevity would increase trap servicing intervals and reduce associated costs. Conducted at 2 sites in Hawaii, the present study investigated the performance of weathered solid dispensers containing 3, 6, or 10 g of methyl eugenol, deployed with solid insecticidal strips, relative to freshly baited liquid-bearing cotton wicks. At the cooler site, the solid lure/toxicant combination captured as many males as the fresh liquid formulation for as long as 12 wk. At the warmer site, the solid lure/toxicant system had shorter longevity, apparently owing to the reduced effectiveness of the insecticidal strip over time.

The oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), is a global agricultural pest that attacks many commercially important fruits and vegetables. Many countries maintain trapping programs to detect incursions of this pest, and trapping relies heavily on methyl eugenol, a powerful attractant to B. dorsalis males, which typically is applied as a liquid to a cotton wick contained inside Jackson traps. However, this method is time-consuming, incurs high volatility (i.e., loss) of the lure, and entails health risks. Existing data indicate that solid dispensers of methyl eugenol are a viable alternative to the use of liquid lure. Based on fieldwork in a Hawaiian coffee field, the present study shows non-significant differences in captures of wild B. dorsalis males over 12-wk intervals between traps baited with a wick containing 6 mL of freshly applied liquid methyl eugenol and traps baited with a polymeric plug or wafer that contained a similar amount of methyl eugenol. The residual content of methyl eugenol also was measured for solid dispensers over the weathering period, but their long-lasting attractancy (≥ 12 wk) precluded identification of the threshold level of the lure below which solid dispensers were ineffective. Implications of these findings for trapping programs are discussed. La mosca oriental de la fruta, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), es una plaga agrícola mundial que ataca una gran variedad de frutas y verduras de importancia comercial. Muchos países mantienen programas de trampeo para detectar incursiones de esta plaga, y el trampeo depende en gran medida del metil eugenol, un poderoso atrayente para los machos de B. dorsalis, que generalmente se aplica como líquido a una mecha de algodón contenida dentro de las trampas Jackson. Sin embargo, este método requiere mucho tiempo, incurre en una alta volatilidad (pérdida) del señuelo y conlleva riesgos para la salud. Los datos existentes indican que los dispensadores sólidos de metil eugenol son una alternativa viable en vez del uso de señuelos líquidos. Basado en el trabajo de campo en cafetal de Hawái, el presente estudio muestra diferencias no significativas en las capturas de machos de B. dorsalis silvestres en intervalos de 12 semanas entre trampas cebadas con una mecha que contiene 6 ml de metil eugenol líquido recién aplicado y trampas cebadas con una tapón polimérico u oblea que contenía una cantidad similar de metil eugenol. El contenido residual de metil eugenol también se midió para dispensadores sólidos durante el período de exposición a la intemperie, pero su atractivo duradero (≥ 12 semanas) impidió la identificación del nivel umbral del señuelo por debajo del cual los dispensadores sólidos eran ineficaces. Se discuten las implicaciones de estos hallazgos para los programas de trampeo.

Detection of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), relies heavily on traps baited with the male attractant trimedlure. This lure is dispensed from solid polymeric plugs (2 g a.i.) that are changed out every 6 wk, because beyond this interval their attractiveness drops significantly below that of fresh lure. Existing data suggest that plugs loaded with 4 g of trimedlure may have longer attractancy, which would allow for longer servicing intervals with associated reductions in material and labor costs. The objective of the present study was to gather additional data on the effectiveness of plugs having trimedlure loadings greater than 2 g. In 4 field experiments conducted in Hawaii, the capture of male medflies was compared over 10 or 12 wk periods between control traps baited with 2 mL fresh liquid trimedlure on a cotton wick and treatment traps baited with aged plugs containing 2 to 4 g of the lure. In all experiments, 6-wk-aged plugs, regardless of the specific loading, attracted similar numbers of males as the fresh liquid lure. Conversely, in 3 of the 4 experiments, plugs aged for 10 or 12 wk attracted significantly fewer males than the fresh lure. The performance of plugs aged 8 wk was inconsistent, showing similar attractiveness as fresh lure in certain cases but not others. Based on these findings, we conclude that, counter to our expectations, the use of 4 g trimedlure plugs would not allow effective trapping over longer inter-servicing intervals.

Bactrocera dorsalis and several Africa-native Ceratitis species are serious constraints to fruit production in sub-Saharan Africa. A long-term trapping and fruit collection study was conducted (2011–2016) in two contrasting agro-ecological zones (AEZs) of Cameroon to determine fruit fly species composition, seasonality, attraction to various lures and baits, and fruit infestation levels. Ten tephritid species from genera Bactrocera, Ceratitis, Dacus, and Perilampsis were captured in traps. Bactrocera dorsalis was the most dominant of the trapped species and persisted throughout the year, with peak populations in May–June. Ceratitis spp. were less abundant than B. dorsalis, with Ceratitis anonae dominating in the western highland zone and Ceratitis cosyra in the humid forest zone. Methyl eugenol and terpinyl acetate captured more B. dorsalis and Ceratitis spp., respectively than Torula yeast. The latter was the most effective food bait on all tephritid species compared with BioLure and Mazoferm. Bactrocera dorsalis was the dominant species emerging from incubated fruits, particularly mango, guava, and wild mango. Four plant species—I. wombolu, Dacryodes edulis, Voacanga Africana and Trichoscypha abut—were new host records for B. dorsalis. This study is the first long-duration and comprehensive assessment of frugivorous tephritid species composition, fruit infestations, and seasonality in Central Africa.

Consuming natural male lure compounds enables the males of some fruit flies (Diptera: Tephritidae) to mate more successfully within their femalechoice mating systems. However, it remains unclear what benefits females derive from mating with lure-fed males. With Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), feeding on the lures cue-lure and zingerone is associated with increased fecundity of mated females, but this direct fitness benefit was not apparent with B. dorsalis (Hendel) (with the lure methyl eugenol) or Zeugodacus cucurbitae (Coquillett) (with the lure cue-lure). Expanding on previous observations, we fed Z. cucurbitae males zingerone, but we observed no evidence of direct fitness benefits to males feeding on zingerone (i.e., mating success and virgin longevity), or to females mated to zingerone-fed males (i.e., longevity, fecundity, and egg viability). We therefore find no reason to reject the runaway selection hypothesis that previously has been proposed to explain lure attraction in B. dorsalis and Z. cucurbitae.