Pumpkin Fruit Fly Research Articles

Phytosanitary cold treatment of cherry tomatoes infested with Bactrocera dorsalis, Zeugodacus cucurbitae, and Zeugodacus tau (Diptera: Tephritidae).

Fruit flies attack numerous crops, including cherry tomatoes (Solanum lycopersicum var. cerasiforme). The potential presence of the immature stages of fruit fly species inside tomatoes during export hinders their international market access. Therefore, phytosanitary treatment must be performed before export to prevent fruit fly species from entering countries where they are not naturally found. We developed a phytosanitary cold disinfestation treatment protocol to eliminate oriental fruit fly (Bactrocera dorsalis Hendel), melon fly (Zeugodacus cucurbitae Coquillett), and pumpkin fruit fly (Zeugodacus tau Walker) concealed inside cherry tomatoes without causing critical damage to the fruit. We determined that the third instar of Z. cucurbitae exhibited the highest cold tolerance among the various development stages of the three fruit fly species. Thus, we performed a small-scale disinfestation test on Z. cucurbitae in two cultivars of tomato. We achieved complete disinfestation after 15 days of cold treatment at 1°C-1.5°C. The confirmatory test revealed the elimination of more than 80,000 treated third instar of Z. cucurbitae in each tomato variety. The developed phytosanitary cold treatment allows the tomatoes to retain their commercial value. This study provides a standard phytosanitary cold treatment protocol for cherry tomatoes, ensuring the disinfestation of fruit flies before their export to international markets.

Laboratory evaluation of interspecific mating between Zeugodacus fruit flies and Bactrocera dorsalis

AbstractThe increasing number of tephritid pest invasions worldwide highlights the importance of interspecific interactions among tephritid pests. The melon fly [Zeugodacus cucurbitae (Coquillett)], the pumpkin fruit fly [Zeugodacus tau (Walker)], and the oriental fruit fly [Bactrocera dorsalis (Hendel)] (all Diptera: Tephritidae) are neotropical fruit flies with overlapping distributions. Their interactions during mating hours have rarely been observed in nature due to their nocturnal behavior. Here, laboratory studies were conducted under no‐choice and choice conditions to quantify interspecific mating. The interactions during mating hours resulted in interspecific mating, which reduced conspecific mating success and interrupted mating activity patterns. Successful interspecific mating pairs of Z. cucurbitae and Z. tau were recorded in no‐choice and choice tests. Interspecific mating between male Z. cucurbitae and female Z. tau significantly reduced conspecific mating in Z. tau. Observations of the diel mating activity patterns showed that male Z. cucurbitae initiated calling behaviors earlier than Z. tau males, giving Z. cucurbitae more chances to court Z. tau. Though males of neither Zeugodacus species formed mating pairs with B. dorsalis, Zeugodacus males reduced conspecific mating in B. dorsalis in the choice trials. Thus, interspecific interactions among Z. cucurbitae, Z. tau, and B. dorsalis affected conspecific mating; interrupted conspecific mating activity patterns were recorded in all three species. This information could be used to improve management practices.

Effects of Sublethal Concentrations of Insecticides on Survival and Reproduction of TwoBactroceraSpecies (Diptera: Tephritidae)

The melon fruit fly, Bactrocera cucurbitae (Coquillett) and the pumpkin fruit fly, Bactrocera tau (Walker) (Diptera: Tephritidae), are important invasive pests on Cucurbitaceous hosts. The acute toxicity of five insecticides to females of these two fruit fly species was bio-assayed by membrane method, and effects of their sublethal concentration on the survival, reproduction, and ovary development of females were evaluated in the laboratory. Results showed that based on the LC50 values, both B. cucurbitae and B. tau were the most susceptible to trichlorfon. After treatment with sublethal concentration (LC30) of trichlorfon, abamectin+β-cypermethrin, spinetoram, and lambda-cyhalothrin, the female survival days of the two Bactrocera species were significantly shortened compared with the control. Moreover, the fecundity of two Bactrocera species was remarkably decreased, after exposure to abamectin+β-cypermethrin and trichlorfon LC30. However, the sublethal concentration (LC30) of insecticides had no significant influence on the egg hatchability of the fruit flies. Furthermore, after treatment with abamectin+β-cypermethrin LC30, the ovary length, width, and egg load of B. cucurbitae were significantly lower than that of the control; however, only the ovarian length and egg load of B. tau were significantly decreased on the 16th and 20th day. In conclusion, abamectin+β-cypermethrin has an excellent insecticidal activity against B. cucurbitae and B. tau.

Morphometric Detection of Mango Fruit Fly Collected from Different Mango Growing Regions of Bangladesh

Thakurgaon districts during the period from April to June 2020 for morphometric detection of mango fruit fly collected from different mango growing regions of Bangladesh. Five locations of each Dinajpur and Thakurgaon district were selected and surveyed for collection of mango fruit fly. The samples were used in detecting the morphometric similarities/dissimilarities at the Entomology Laboratory of Sher-e-Bangla Agricultural University. The locations for collection of the samples in Dinajpur district were Biral, Bochagonj, Kaharole, Fulbari and Khanshama and in Thakurgaon were Sadar, Pirganj, Ranisankail, Baliadangi and Haripur. Data were collected on wing, head, thorax and abdomen of fruit flies and further study was ensured. The fruit fly samples were collected using pheromone trap (methyl-eugenol) at mango orchards. Four different species were morphometrically identified using stereomicroscope. Oriental fruit fly (Bactrocera dorsalis), melon fruit fly (Zeugodacus cucurbitae), pumpkin fruit fly (Zeugodacus tau), and peach fruit fly (Bactrocerazonata) were the four species of fruit flies that were identified. Total 85.41% of oriental fruit flies were found in pheromone trap which was the highest in number among the collected species. However, 2.44 % of peach fruit fly were identified which was the lowest number of fruit fly. Moreover, 8.81% and 3.34% percent of melon fruit fly and pumpkin fruit fly were collected from pheromone trap respectively. Therefore, number of oriental fruit flies were highest compared to others. The highest infestations were observed at Dinajpur district compared to Thakurgaon district in mango orchard. Dinajpur district’s oriental fruit fly was larger compared to Thakurgaon district’s oriental fruit flies

Trapping tephritid fruit flies (Diptera: Tephritidae) in citrus groves of Fujian Province of China

Abstract Certain tephritid fruit flies, such as the oriental fruit fly, Bactrocera dorsalis , the Chinese citrus fly, B. minax and the Japanese orange fly, B. tsuneonis (Diptera: Tephritidae: Dacinae), are destructive citrus pests in China. A two-year trapping study was conducted in pomelo, Citrus maxima, groves in Fujian Province of China. The objectives of this study were to investigate the species, the abundance of tephritid fruit flies in the orchards, as well as the efficacy of the selected lure traps to these flies. Four lure traps or devices, i.e. methyl eugenol + Steiner trap (ST), cuelure + ST, ammonium acetate + putrescine + ST, and sticky spheres, were deployed from June to November 2017 and April to October 2018. Six economically significant Dacini pests were trapped during the period. These flies are B. dorsalis, the melon fruit fly, Zeugodacus cucurbitae, the pumpkin fruit fly, Z. tau, the Malaysian fruit fly, B. latifrons, and other two species - B. rubigina and Z. scutellatus. B. dorsalis was the most abundant, accounting for more than 50% of the capture, followed by Z. cucurbitae. The remaining four species accounted for less than 2% of the total capture. B. minax and B. tsuneonis, two destructive citrus-damaging tephritid fruit flies in China, were not found during the trapping period. Methyl eugenol trapped the highest number of fruit flies, followed by cuelure.

Morphological and functional heterogeneity in olfactory perception between antennae and maxillary palps in the pumpkin fruit fly, Bactrocera depressa.

The morphology and ultrastructure of the olfactory sensilla on the antennae and maxillary palps were investigated through scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and their responses to five volatile compounds were measured using electroantenogram (EAG) and electropalpogram (EPG) techniques in the pumpkin fruit fly, Bactrocera depressa (Shiraki; Diptera: Tephritidae). Male and female B. depressa displayed distinct morphological types of olfactory sensilla in the antennae and maxillary palps, with predominant populations of trichoid, basiconic, and coeloconic sensilla. Basiconic sensilla, the most abundant type of olfactory sensilla in the antennae, could be further classified into two different types. In contrast, the maxillary palps exhibited predominant populations of a single type of curved basiconic sensilla. High-resolution SEM observation revealed the presence of multiple nanoscale wall-pores on the cuticular surface of trichoid and basiconic sensilla, indicating that their primary function is olfactory. In contrast, coeloconic sensilla displayed several longitudinal grooves around the sensillum peg. The TEM observation of individual antennal olfactory sensilla indicates that the basiconic sensilla are thin-walled, while the trichoid sensilla are thick-walled. The profile of EAG responses of male B. depressa was different from their EPG response profile, indicating that the olfactory function of maxillary palps is different from that of antennae in this species. The structural and functional variation in the olfactory sensilla between antennae and maxillary palps suggests that each plays an independent role in the perception of olfactory signals in B. depressa.

Characterization of mitogenome for pumpkin fruit fly, Zeugodacus tau (Walker) (Diptera: Tephritidae) from Kunming, Southwest China and the phylogeny within subfamily Dacinae

Zeugodacus tau (Walker) (Diptera: Tephritidae), is widely distributed throughout South and Southeast Asia. complete sequence of the mitogenome of Z. tau has been determined in this study. The circular genome is 15830 bp long and contains a standard gene complement, that is, the large and small ribosomal RNA subunits, 22 transfer RNA genes, 13 genes encoding mitochondrial proteins, and a non-coding A + T-rich control region. The phylogeny showed that Z. tau is closely related to Z. depressus with high bootstrap value supported and that monophyletic Bactrocera, Zeugodacus, and Ceratitidini were correctly identified within subfamily Dacinae.

Identification and characterization of doublesex from the pumpkin fruit fly, Bactrocera tau (Diptera: Tephritidae)

The sex determination cascades in insects are diversified at the top of the cascade, where different primary molecular signals are employed, while at the bottom of the cascades, particularly the doublesex genes, are highly conserved. Here, we identified the doublesex ortholog (Btau-dsx) of Bactrocera tau, a pumpkin fruit fly, and found that Btau-dsx is composed of six exons and five introns with an additional short "m" exon located in the second intron. Btau-dsx is different from its orthologs in most dipteran insects: Its pre-mRNA is sex-specifically spliced to yield three (two male and one female) instead of two transcript variants. The two deduced proteins produced by the male-specific transcripts are a functional (Btau-DSXM1) and a truncated (Btau-DSXM2) protein, while the female-specific transcript produces the functional Btau-DSXF protein. These three proteins contain all conserved domains except Btau-DSXM2 which has no OD2 domain. The female-specific transcript is detected in both fertilized and unfertilized eggs and in both somatic and germ cells of the adult females, while the male-specific transcript is detected only in fertilized eggs and in the abdominal tissues and testes of adult males. The presence of the Btau-dsxM1 transcript in fertilized eggs at the early syncytium stage suggests that in XY embryos, the Y-linked M factor gene may function quite soon after fertilization to alter the splicing pattern of Btau-dsx pre-mRNA from the female-specific to the male-specific mode. Injection of Btau-dsxF dsRNA into recently emerging females can reduce the expression of vitellogenin (Btau-Vg) and causes some defects in the ovaries, indicating that Btau-dsxF works upstream of Btau-Vg.

The transformer2 gene of the pumpkin fruit fly, Bactrocera tau (Walker), functions in sex determination, male fertility and testis development.

The insect transformer2 (tra2) gene has a prevalent role in cooperating with the sex-determining gene transformer (tra) to direct female differentiation. Here, we report the identification and characterization of Btau-tra2, the tra2 orthologue of the pumpkin fruit fly, Bactrocera tau, an invasive agricultural pest. The Btau-tra2 gene produces three transcript variants. However, only two transcripts can be examined; one is present at all developmental stages in the soma and germline of both sexes and the other one is specific to the embryo and the germline. Knocking down the function of Btau-tra2 produced a male-biased sex ratio and some intersexes. Consistent with a role in sex determination, the obtained intersexual and male sterility phenotypes express a mix of male and female splice variants of the tra and doublesex (dsx) orthologues, indicating that Btau-tra2 has a conserved splicing regulatory function and acts together with/upstream of tra and dsx. In addition, some males obtained from the knock down are fertile but their fertilities are extremely reduced. Moreover, almost all surviving RNA interference (RNAi) males harbour testes having some defects in their external morphologies. Most notably, the body size of a few surviving RNAi flies was two-to threefold increased with respect to the normal size. Our findings suggest that Btau-tra2 is involved in male fertility and may also have an unprecedented role in body size control besides its conserved role in sex determination.

Taxonomy of Korean Bactrocera (Diptera: Tephritidae: Dacinae) with review of their biology

The genus Bactrocera Macquart, currently comprising over 650 described species, is the most economically significant fruit fly genus with at least about 50 species considered to be pests of agricultural and quarantine importance. As a part of effort to investigate both agricultural and quarantine Bactrocera pests in Korea, the present study aims at reviewing the naturally occurring Bactrocera species in this country. Two Bactrocera species, pumpkin fruit fly (B. depressa (Shiraki)) and striped fruit fly (B. scutellata (Hendel)), are currently recognized in South Korea. Bactrocera depressa is an important agricultural pest infesting pulp of host fruits including pumpkins, and B. scutellata is known to infest flower buds of pumpkins as well as other cucurbit hosts. We recently found the third Bactrocera species, B. hyalina (Shiraki), for the first time in Korea. We here provide a taxonomic key to the Korean Bactrocera species, brief review of their biology, summary of their taxonomic status, diagnoses, descriptions, and detailed photographs of adults including postabdominal structures for their accurate identification. In addition, we here synonymize Zeugodacus bezzianus Hering with B. depressa.

Complete mitochondrial genome of the pumpkin fruit fly, Bactrocera depressa (Diptera: Tephritidae)

In this study, we sequenced the complete mitochondrial genome (mitogenome) of the pumpkin fruit fly, Bactrocera depressa (Diptera: Tephritidae), which is an economically damaging pest of pumpkin and turban squash. The 15,832-bp-long complete mitogenome of the species consists of a typical set of genes, with an arrangement typical of insects. Of the 13 protein-coding genes (PCGs), 12 have a typical ATN start codon, whereas the COI gene begins with TCG, which has been identified as the start codon for all Bactrocera COI genes. The 1004-bp A + T-rich region of B. depressa is the third longest, after B. minax and B. scutellata, of the Bactrocera species for which the whole mitogenome has been sequenced. Phylogenetic analysis using the 13 PCGs of Bactrocera species indicated that B. depressa is a sister to the sister group containing B. tau and B. cucurbitae with the highest nodal support (Bayesian posterior probability =1.0).

The complete mitochondrial genome of the pumpkin fruit fly, Bactrocera tau (Diptera: Tephritidae)

The pumpkin fruit fly, Bactrocera tau, is an important quarantine pest in many countries because of its mass destructiveness to a variety of vegetable and fruit plants. In this study, we report the complete mitochondrial genome (mitogenome) of B. tau. Its complete mitogenome sequence is 15,687 bp in length, which contains a non-coding control region and all of the 37 genes of bilaterian animals (13 protein-coding genes, 22 tRNA genes and 2 rRNA genes). A phylogenetic tree of the complete mitogenome of all available Tephritidae species was established to approve the accuracy. The base composition of mitogenome sequence and the gene arrangement including directions are rather conservative, compared to other published mitogenomes of Bactrocera species. This first complete mitogenome of B. tau will facilitate the development of new DNA markers for species diagnosis, therefore improving accurate detection of quarantine species.

Bitter gourd growers pesticides use pattern in controlling insect-pests and diseases in Nadia district of West Bengal

effect on soil health and environment has created an alarming situation. A situation has resulted which urgently demands an environmentally safe, sustainable and simultaneously, economically viable production system. This indeed is essential for optimizing production and at the same time to minimize threat to environment. Considering the importance of the study, the objective, to portray the pesticides use pattern in bitter gourd in controlling insect-pests and diseases was undertaken. The study was conducted in Nadia district of West Bengal. For the selection of area and respondents of the present study, multi-stage random sampling technique and universe method were adopted. The study reveals that the most harmful insect-pest of bitter gourd crop was pumpkin fruit fly, downy mildew disease was the most damaging disease, bitter gourd growers were using various brands of various technical grade of pesticides for controlling insect-pests and diseases with several doses, infestation of insect-pests and diseases was mainly seen on mature stage of the crop, main source of information on pesticides use was agricultural input retailers, the bitter gourd growers used 40-60 lit. and 60-90 lit. of water per bigha of land (1 acre=3 bighas) for spraying at seedling stage and mature stage, respectively, their interval of spraying of chemicals was mainly 4-7 days and spraying was most popular method of application of pesticides. Therefore, on the basis of the present investigation, the various extension agencies those are working in the study area should reorient their extension strategies accordingly.

Population genetic structure of the pumpkin fruit fly, Bactrocera tau (Walker) (Diptera: Tephritidae) in Himachal Pradesh, India

The population genetic structure of the pumpkin fruit fly, Bactrocera tau, a fruit fly pest that causes significant losses to cucurbit cultivations, has been studied in Himachal Pradesh (India) using mitochondrial cytochrome oxidase I (mtCOI) gene sequences. Levels of differentiation (genetic distances and FST values) among samples from different locations are minimal, suggesting the local occurrence of a large and geographically undifferentiated population, with the possible exception of population Solan. Nevertheless, overall genetic variability is substantial, with 10 different haplotypes detected in 16 individuals and only one of these – likely the original one as it occupies a central position in the network and is found at a relatively high frequency –shared between multiple populations. The phylogenetic analysis of local B. tau samples in the context of the different sibling species that constitute the B. tau complex in its South-East Asia region of origin revealed that local B. tau is closely related to B. tau species A from Thailand. This should be taken into account in any intervention aimed at the control of this pest, e.g. area wide integrated pest management (AW IPM). The marked local genetic uniformity and predominance of one single species of the species complex further suggest that the sterile insect technique (SIT) may be a viable option.

호박과실파리 발생생태 및 계절초기 성충우화시기 예찰 모형

호박과실파리(Bactrocera depressus)는 파리목 과실 파리과에 속한 곤충으로 박과류 작물의 중요한 해충이다. 이 연구는 호박과실파리의 호박 피해관련 기초생태를 구명하고 성충우화시기 예찰모형을 개발하고자 수행하였다. 애호박 생산농가에서 호박과실파리 산란 흔적은 7월 중하순부터 발생되기 시작하여 8월 하순 최성기를 보였으며 9월 하순부터는 발견되지 않았으며, 이 기간이 호박과실파리 산란활동 시기로 판단되었다. 숙과호박 농가에서는 7월 하순 어린 과실에 산란 흔적이 발견되었고 8월 이후 유충에 의한 호박의 부패가 시작, 10월까지 피해과가 급격히 증가하였다. 호박과실파리 산란흔적은 호박 과실 당 평균 2.2개가 발견되었으며, 과실 당 <TEX>$28.8{\sim}29.8$</TEX>개의 산란수를 보였다. 우화트랩으로 조사한 호박과실파리 월동번데기의 우화시기는 초발일이 5월 중순에서 하순 사이로 나타났고, 최성기는 5월 하순 내지 6월 상순이었다. 호박과실파리 월동번데기의 우화까지 발육기간은 <TEX>$15^{\circ}C$</TEX>에서 59.0일, <TEX>$20^{\circ}C$</TEX> 39.3일, <TEX>$25^{\circ}C$</TEX> 25.8일, <TEX>$30^{\circ}C$</TEX> 21.4일이었고 <TEX>$35^{\circ}C$</TEX>에서는 발육하지 못하였다. 온도와 월동번데기 발육기간 관계에 대한 선형모형 추정결과는 발육영점온도는 <TEX>$6.8^{\circ}C$</TEX>로 추정되었고 발육완료에 필요한 적산온도는 482.3 DD 이었다. 또한 월동번데기 발육률과 온도와 비선형적 관계는 Gaussian 모형으로 잘 설명되었다. 적산온도 모형으로 50% 성충우화일을 예측한 결과 실측치와 편차가 1일로 적중률이 높았다. 또한 발육모형과 발육완료시기 분포모형(Weibull 함수)을 이용한 발율률 적산모형의 예측치는 실측치의 우화양상과 유사하였다. 본 연구결과는 향후 호박과실파리의 관리전략 수립에 유용하게 이용될 수 있을 것으로 기대된다. The pumpkin fruit fly, Bactrocera depressa (Tephritidae: Diptera), is one of the most important pests in Cucurbitaceae plants. This study was conducted to investigate the basic ecology of B. depressa, and to develop a forecasting model for predicting the time of adult emergence in early season. In green pumpkin producing farms, the oviposition punctures caused by the oviposition of B. depressa occurred first between mid- and late July, peaked in late August, and then decreased in mid-September followed by disappearance of the symptoms in late September, during which oviposition activity of B. depressa is considered active. In full-ripened pumpkin producing farms, damaged fruits abruptly increased from early Auguest, because the decay of pumpkins caused by larval development began from that time. B. depressa produced a mean oviposition puncture of 2.2 per fruit and total 28.8-29.8 eggs per fruit. Adult emergence from overwintering pupae, which was monitored using a ground emergence trap, was first observed between mid- and late May, and peaked during late May to early June. The development times from overwintering pupae to adult emergence decreased with increasing temperature: 59.0 days at <TEX>$15^{\circ}C$</TEX>, 39.3 days at <TEX>$20^{\circ}C$</TEX>, 25.8 days at<TEX>$25^{\circ}C$</TEX> and 21.4 days at <TEX>$30^{\circ}C$</TEX>. The pupae did not develop to adult at <TEX>$35^{\circ}C$</TEX>. The lower developmental threshold temperature was calculated as <TEX>$6.8^{\circ}C$</TEX> by linear regression. The thermal constant was 482.3 degree-days. The non-linear model of Gaussian equation well explained the relationship between the development rate and temperature. The Weibull function provided a good fit for the distribution of development times of overwintering pupae. The predicted date of 50% adult emergence by a degree-day model showed one day deviation from the observed actual date. Also, the output estimated by rate summation model, which was consisted of the developmental model and the Weibull function, well pursued the actual pattern of cumulative frequency curve of B. depressa adult emergence. Consequently, it is expected that the present results could be used to establish the management strategy of B. depressa.

Incidence of Insect Pests on Chayote, &lt;i&gt;Sechium edule&lt;/i&gt; (Swartz.) in Nepal

The insect pests recorded during 1993-96 on chayote in Chitwan, Lalitpur and Parbat districts were as follows: white grubs (Phyllophaga spp.), mole cricket (Gryllotalpa fussor Fab.), field cricket (Brachytrypes portentosus Licht.), red pumpkin beetle (Aulacophora foveicollis Lucas), blue pumpkin beetle (Aulacophora lewisii Baly), flea beetle (Monolepta signata Oliv.), tobacco caterpillar (Spodoptera litura Fab.), stink bug (Coridius janus Fab.), spotted beetle (Epilachna pusilanima Mulsant), banded blister beetle (Mylabris phalerata Pallas), brown bug (Agonoscelis nubila Fab.), cotton aphid (Aphis gossypii Glov.), pumpkin fruit fly (Bacterocera cucurbitae Coq.), and three unidentified insect pests- brown weevil, hairy caterpillars and stem boring beetle. Of them, the fruit fly and cotton aphid were the serious ones. Nepalese and Mexican accessions of chayotes varied for their susceptibility to both the above insects. The chayote fruits with tough fruit skin and dense and long spines were less susceptible to fruit fly, while the spineless and smooth fruits were the most susceptible. &#x0D; &#x0D; Key words: Chayote germplasm, insect pests, aphid and fruit fly &#x0D; &#x0D; J. Inst. Agric. Anim. Sci. 27:161-164 (2006)

Molecular Genetic Diagnosis of Four Fruit Fly Species (Tephritidae)

The true fruit flies (Diptera: Tephritidae) are major agricultural pests worldwide. In Korea, imported crops are carefully scrutinized to prevent infestation by exotic tephritids and rapid species identification is required to make quarantine decisions. At quarantine checkpoints, tephritids are most commonly intercepted at the larval stage, however larvae have few diagnostic morphological features. Here we describe a molecular genetic method using restriction enzyme digestions of PCR products from the mitochondrial gene, cytochrome oxidase I (COI). This technique provides a simple diagnostic marker for Korean fruit flies in the genus Bactrocera ( B. depressa, pumpkin fruit fly; and B. scutellata, pumpkin flower fruit fly) and wide spread fruit flies ( B. dorsalis, oriental fruit fly; and Ceratitis capitata, medfly). The restriction enzymes ApaI, NheI and SacI were used to digest the 815 bp PCR product into fragments that uniquely diagnose each species. The simplicity and relatively low cost of this molecular approach will facilitate rapid quarantine decisions concerning exotic fruit flies.