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We examined spatial patterns of both sexes of oriental fruit fly, Bactrocera dorsalis (Hendel), and its two most abundant parasitoids, Fopius arisanus (Sonan) and Diachasmimorpha longicaudata (Ashmead) in a commercial guava (Psidiumguajava L.) orchard. Oriental fruit fly spatial patterns were initially random, but became highly aggregated with host fruit ripening and the subsequent colonization of, first, F. arisanus (egg-pupal parasitoid) and, second, D. longicaudata (larval-pupal parasitoid). There was a significant positive relationship between populations of oriental fruit fly and F. arisanus during each of the F. arisanus increases, a pattern not exhibited between oriental fruit fly and D. longicaudata. Generally, highest total numbers of males and females (oriental fruit fly, F arisanus, and D. longicaudata) occurred on or about the same date. There was a significant positive correlation between male and female populations of all three species; we measured a lag of 2-4 wk between increases of female F. arisanus and conspecific males. There was a similar trend in one of the two years for the second most abundant species, D. longicaudata, but no sign of a time lag between the sexes for oriental fruit fly. Spatially, we found a significant positive relationship between numbers of F arisanus in blocks and the average number in adjoining blocks. We did not find the same effect for oriental fruit fly and D. longicaudata, possibly a result of lower overall numbers of the latter two species or less movement of F. arisanus within the field [ABSTRACT FROM AUTHOR]

Bactrocera fruit fly species are economically important throughout the Pacific. The USDA, ARS U.S. Pacific Basin Agricultural Research Center has been a world leader in promoting biological control of Bactrocera spp. that includes classical, augmentative, conservation and IPM approaches. In Hawaii, establishment of Bactrocera cucurbitae (Coquillett) in 1895 resulted in the introduction of the most successful parasitoid, Psyttalia fletcheri (Silvestri); similarly, establishment of Bactrocera dorsalis (Hendel) in 1945 resulted in the introduction of 32 natural enemies of which Fopius arisanus (Sonan), Diachasmimorpha longicaudata (Ashmead) and Fopius vandenboschi (Fullaway) were most successful. Hawaii has also been a source of parasitoids for fruit fly control throughout the Pacific region including Australia, Pacific Island Nations, Central and South America, not only for Bactrocera spp. but also for Ceratitis and Anastrepha spp. Most recently, in 2002, F. arisanus was introduced into French Polynesia where B. dorsalis had invaded in 1996. Establishment of D. longicaudata into the new world has been important to augmentative biological control releases against Anastrepha spp. With the rapid expansion of airline travel and global trade there has been an alarming spread of Bactrocera spp. into new areas of the world (i.e., South America and Africa). Results of studies in Hawaii and French Polynesia, support parasitoid introductions into South America and Africa, where B. carambolae and B. invadens, respectively, have become established. In addition, P. fletcheri is a candidate for biological control of B. cucurbitae in Africa. We review past and more recent successes against Bactrocera spp. and related tephritids, and outline simple rearing and release methods to facilitate this goal. [ABSTRACT FROM AUTHOR]

MultiLure traps were deployed in a Hawaiian orchard to compare the attraction of economically important fruit flies and nontarget insects to the three-component BioLure and torula yeast food lures. Either water or a 20% propylene glycol solution was used to dissolve the torula yeast or as capture fluid in BioLure traps. Torula yeast in water was more attractive than BioLure for male and female Bactrocera Cucurbitae (Coquillett) and Bactrocera dorsalis (Hendel) and as attractive for Ceratitim capitata (Wiedemann), and the addition of propylene glycol significantly inhibited the attractiveness of torula yeast. The known synergistic effect of propylene glycol with BioLure, resulting in increased captures oiAnastrepha flies, was not observed with Bactrocera. Nontarget Drosophilidae, Neriidae, Phoridae, Calliphoridae, Sarcophagidae, and Muscidae were more strongly attracted to BioLure, and both lures collected Chloropidae equally. As with fruit flies, propylene glycol in torula yeast significantly decreased nontarget captures. The results therefore suggest that torula yeast in water is a more effective attractant than BioLure for pest Bactrocera while minimizing nontarget captures. [ABSTRACT FROM AUTHOR]

Methyl eugenol (ME) and cue-lure (C-L) traps with solid lure dispensers were deployed in areas with low and high populations of oriental fruit fly, Bactrocera dorsalis (Hendel), and melon fly, Bactrocera cucurbitae (Coquillett),respectively. In low-density areas, standard Jackson traps or Hawaii Fruit Fly Areawide Pest Management (AWPM) traps with FT Mallet ME wafers impregnated with dimethyl dichloro-vinyl phosphate (DDVP) or AWPM traps with Scentry ME cones and vapor tape performed equally as well as standard Jackson traps with liquid ME/C-L and naled. Standard Jackson traps or AWPM traps with FT Mallet C-L wafers impregnated with DDVP or AWPM traps with Scentry C-L plugs with vapor tape performed equally as well as standard Jackson traps with a lure-naled solution. In high density areas, captures with traps containing FT Mallet wafers (ME and C-L) outperformed AWPM traps with Scentry cones and plugs (ME and C-L) with DDVP insecticidal strips over a 6-mo period. Captures of B. dorsalis and B. cucurbitae with wafers containing both ME and raspberry ketone (FT Mallet MC) were equivalent to those containing separate lures. From a worker safety and convenience standpoint, FT Mallet ME and C-L wafers with DDVP or Scentry plugs, with or without DDVP vapor tape, are more convenient and safer to handle than standard liquid insecticide formulations used for monitoring and male annihilation programs in Hawaii, and for detections traps used on the U.S. mainland. Furthermore, the FT Mallet MC wafer might be used in a single trap in place of two separate traps for detection of both ME and C-L responding fruit flies. [ABSTRACT FROM AUTHOR]

Synthetic male lures are commonly used to monitor and mass trap pestiferous fruit flies (Diptera: Tephritidae: Dacinae). However, there has been much dispute as to the nontarget impacts of such lures on beneficial and native insects. To evaluate nontarget attraction effects, traps baited with Cue-Lure and methyl eugenol were maintained and emptied weekly in a range of native and non-native forest and commercial orchard and backyard sites on Hawaii and Maui Islands. Lure trap captures were compared against those from unbaited control traps and traps artificially baited with decaying fruit flies to mimic the effect of accumulation of dead trapped target flies in male lure traps. Cue-Lure did not attract nontargets, and methyl eugenol attracted low but significant numbers of five species of flower-associated insects (honey bees, syrphid flies, nitidulid beetles, and endemic ci-ambid moths) and two endemic Hawaiian species of sciarids (Diptera) and minds (Hemiptera). Saprophagous nontargets, mostly Diptera, were abundant and diverse in traps baited with decaying flies and in male lure traps where accumulation of dead flies occurred but not in male lure traps with few or no fruit fly captures. Most of the previously published records of attraction to methyl eugenol are shown to actually be secondary attraction to decaying fruit flies. Endemic nontargets were collected in native and adjacent forest, but almost exclusively invasive species were attracted to traps placed in non-native habitats. Attraction of flower-associated species may be minimized if methyl eugenol traps are placed in trees after flowering season in orchards. [ABSTRACT FROM AUTHOR]

Endemic Hawaiian Drosophilidae, a radiation of nearly 1000 species including 13 federally listed as endangered, occur mostly in intact native forest, 500-1500 m above sea level. But their persistence in disturbed forest and agricultural areas has not been documented. Thus, control efforts for agricultural pests may impact endemic species if previously undocumented refugia in agricultural areas may play a role in their conservation. To quantify whether invasive plants and agriculture habitats may harbor endemic Drosophilidae, we established standardized trapping arrays, with traps typically designed to control invasive fruit flies (Tephritidae), with 81 sites across native, disturbed and agricultural land use gradients on the islands of Hawai'i and Maui. We collected and identified, to species level, over 22,000 specimens. We found 121 of the possible 292 species expected to occur in the sampled areas, and the majority (91%) of the captured specimens belonged to 24 common species. Species diversity and numbers were greatest in the native forest, but 55% of the species occurred in the invasive strawberry guava belt and plantation forest, adjacent to and almost 500 m from native forest, and 22 species were collected in orchards and nonnative forest as far as 10 km from native habitats. Their persistence outside of native forest suggests that more careful management of disturbed forest and a reassessment of its conservation value are in order. Conservation efforts and assessments of native forest integrity should include the subset of species restricted to intact native forest, since these species are highly localized and particularly sensitive. Additionally, future efforts to control invasive pest fruit flies should consider the nontarget impacts of maintaining traps in and near native forest. This survey project demonstrates the utility of thorough biotic surveys and taxonomic expertise in developing both sensitive species lists and baseline diversity indices for future conservation and monitoring efforts.

BioLure, a synthetic food attractant for Mediterranean fruit fly [Ceratitis capitata (Wiedemann)], is composed of three chemicals (ammonium acetate, trimethylamine hydrochloride, and putrescine). We deployed these components together and in separate MultiLure traps across predominantly native forests, non-native forests, farmlands, orchards, and residential areas on the islands of Hawaii and Maui, to evaluate attraction of C. capitata and nontarget insects. Large numbers (as many as 186 per trap per day) of mainly saprophagous nontarget flies (primarily Drosophilidae, Chloropidae, Lonchaeidae, Neriidae, Otitidae, and Calliphoridae) were attracted to BioLure. Very few predators, parasitoids, or pollinators were attracted. Native species, predominantly drosophilid and calliphorid flies, were attracted in large numbers in endemic forests, but mostly (at least 88%) introduced species were collected in orchards, backyards, and non-native forest. A comparison of attraction to the three separate components versus combined components in traps revealed that ammonium acetate and, to a lesser extent, putrescine are the key components attractive to nontarget species. Omitting the putrescine ingredient from BioLure did not drastically decrease C. capitata catches but reduced nontarget captures by 20%.

Worldwide, an important aspect of invasive insect pest management is more effective, safer detection and control systems. Phenyl propanoids are attractive to numerous species of Dacinae fruit flies. Methyl eugenol (ME) (4-allyl-1, 2-dimethoxybenzene-carboxylate), cue-lure (C-L) (4-(p-acetoxyphenyl)-2-butanone), and raspberry ketone (RK) (4-(p-hydroxyphenyl)-2-butanone) are powerful male-specific lures. Most evidence suggests a role of ME and C-L/RK in pheromone synthesis and mate attraction. ME and C-L/RK are used in current fruit fly programs for detection, monitoring, and control. During the Hawaii Area-Wide Pest Management Program in the interest of worker safety and convenience, liquid C-L/ME and insecticide (i.e., naled and malathion) mixtures were replaced with solid lures and insecticides. Similarly, Male Annihilation Technique (MAT) with a sprayable Specialized Pheromone and Lure Application Technology (SPLAT), in combination with ME (against Bactrocera dorsalis, oriental fruit fly) or C-L/RK (against B. cucurbitae, melon fly), and the reduced-risk insecticide, spinosad, was developed for area-wide suppression of fruit flies. The nontarget effects of ME and C-L/RK to native invertebrates were examined. Although weak attractiveness was recorded to flower-visiting insects, including bees and syrphid flies, by ME, effects to native Drosophila and other Hawaiian endemics were found to be minimal. These results suggested that the majority of previously published records, including those of endemic Drosophilidae, were actually for attraction to dead flies inside fruit fly traps. Endemic insect attraction was not an issue with C-L/RK, because B. cucurbitae were rarely found in endemic environments., (Copyright © 2010 Elsevier Inc. All rights reserved.)