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We have been studying the behavioural and physiological mechanisms associated with coordination of reproductive maturity and sex pheromone communication in male tephritid flies in order to develop methods for acceleration of reproductive maturity among sterilized males. Our studies revealed that exposure to the juvenile hormone analogue methoprene can accelerate the rate of sexual maturity in some but not all tephritid species tested. Additionally, we have determined that incorporation of protein hydrolysate into the adult diet improves sexual performance of sterile males. Coupling a diet enriched with protein hydrolysate for adult food and application of methoprene to adult males or pupae was found to advance significantly the age at which males of a number of species of flies from the genus Anastrepha and Bactrocera cucurbitae (Coquillet) become sexually mature and improve reproductive success of the males. These results have led to the development of a novel strategy to accelerate the reproductive development and increased competitiveness of mass-reared fruit flies for use in the sterile insect technique by incorporating methoprene treatment and protein hydrolysate diets into protocols for fruit fly emergence and release facilities. The following reviews research conducted to develop the system and our suggestions for use in improving efficacy of mating by sterile males destined for release in programmes to control some species of tephritid flies using the sterile insect technique.

We report here a cytogenetic analysis of the melon fly, Bactrocera Cucurbitae, Coquillett (Diptera: Tephritidae), a species of significant agricultural importance. The mitotic karyotype and detailed photographic maps of the larval salivary gland polytene chromosomes of the species are presented. The mitotic karyotype consists of six pairs of chromosomes including one pair of heteromorphic sex (XX/XY) chromosomes. The heterogametic sex is ascribed to the male. The analysis of polytene chromosomes has shown a total number of five long polytene elements (10 polytene arms) that correspond to the five autosomes. The characteristic features and the most prominent landmarks of each polytene chromosome are presented. The proposed chromosomal homology between B. Cucurbitae and Mediterranean fruit fly, Ceratitis capitata (Wiedemann), was determined by comparing chromosome banding patterns. The detection of heterozygous chromosome inversions in two strains is shown and discussed. The current study provides workable polytene chromosome maps of the species and compares our results with previous reports. We show that these maps can be used for cytogenetic studies in the species and for comparative studies among the tephritid species. They also can support the development of control methods and clarify the taxonomic status of B. cucurbitae.

Reproductive isolation among populations of Anastrepha fraterculus has been found acting at the pre- and post-zygotic levels. Differences in timing of sexual activity and male sexual pheromone composition among populations could partially account for prezygotic isolation. Hybrid males were found to produce a novel pheromone, which is a mix of parental pheromones. In the present study, we found that the hybrid females showed a significant preference to mate with hybrid males than with parental males. Male location during pheromone emission is associated with its reproductive success and, thus, differences in the location of males during courtship could also play a role in isolation. We found evidence that reproductive isolation is also related to the location of males during courtship. Hybrid male behaviour regarding location during pheromone release was found to be influenced by the maternal lineage. If these populations hybridized in the field, the hybrid females would tend to mate with hybrid males probably leading to the formation of a new entity within the A. fraterculus complex. This simple and fast process could be one reason explaining the high number of taxonomic entities within this complex. Further studies on other members of the fraterculus species group may reveal whether this can be considered as an example of homoploid hybrid speciation. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 346–354.

The application of the Sterile Insect Technique (SIT) in area-wide integrated pest management (AW-IPM) programmes continues to increase. However, programme efficiency can still be considerably enhanced when certain components of the technology are improved, such as the development of improved strains for mass rearing and release. These include strains that (1) produce only male insects for sterilization and release and (2) carry easily identifiable markers to identify released sterile insects in the field. Using both classical and modern biotechnology techniques, key insect pests are targeted, where SIT programmes are being implemented. The pests include mosquitoes, the Mexican fruit fly, the codling moth, the oriental fruit fly and the pink bollworm. This special issue summarizes the results of research efforts aimed at the development and evaluation of new strains to a level where a decision can be made as to their suitability for use in large scale SIT programmes. Major beneficiaries will be operational AW-IPM programmes that apply the SIT against major insect pests.

The application of methoprene, and providing access to diet including hydrolyzed yeast, are treatments known to enhance mating success in the male melon fly Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), supporting their use in mass rearing protocols for sterile males in the context of sterile insect technique (SIT) programmes. The objective of the present laboratory study was to investigate the effect of methoprene application and diet supplementation with hydrolyzed yeast (protein) on the turnover of body lipids and protein to confirm the feasibility of their application in melon fly SIT mass-rearing programmes. While females had access to a diet that included hydrolyzed yeast (protein), males were exposed to one of the following treatments: (1) topical application of methoprene and access to diet including protein (M+P+); (2) only diet including protein (M-P+); (3) only methoprene (M+P-) and (4) untreated, only sugar-fed, control males (M-P-). Total body carbon (TBC) and total body nitrogen (TBN) of flies were measured at regular intervals from emergence to 35 days of age for each of the different treatments. Nitrogen assimilation and turnover in the flies were measured using stable isotope ((15)N) dilution techniques. Hydrolyzed yeast incorporation into the diet significantly increased male body weight, TBC and TBN as compared to sugar-fed males. Females had significantly higher body weight, TBC and TBN as compared to all males. TBC and TBN showed age-dependent changes, increasing until the age of sexual maturity and decreasing afterwards in both sexes. Methoprene treatment did not significantly affect TBC or TBN. The progressive increase with age of TBC suggests that lipogenesis occurs in adult male B. cucurbitae, as is the case in other tephritids. Stable isotope dilution was shown to be an effective method for determining N uptake in B. cucurbitae. This technique was used to show that sugar-fed males rely solely on larval N reserves and that the N uptake rate in males with access to diet including hydrolyzed yeast was higher shortly after emergence and then stabilized. The implications of the results for SIT applications are discussed.

The application of methoprene and access to protein in adult diet has been shown to enhance mating success in male melon fly Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), supporting their incorporation into operational area-wide programmes integrating the Sterile Insect Technique (SIT). The objective of the present study was to investigate the effect of methoprene, diet including protein and feeding days on male starvation survival to determine the minimum number of feeding days required prior to male release in the field. The study was performed in the laboratory by treating males with (i) both protein and methoprene (M+P+), (ii) only protein (M−P+), (iii) only methoprene (M+P−) or (iv) untreated (M−P−). The males were starved after exposure for an increasing number of days (1–7) to their respective treatment. Mean longevity was highest after 3-day post-emergence feeding duration for M+P+, M+P− and M−P− males, but 4 days of feeding for M−P+ males. Additional feeding days after 4 days, did not increase male survival and feeding for 7 days decreased starvation survival of sugar-fed males. Application of methoprene and/or access to diet including protein had no adverse effect on starvation survival but feeding duration had a significant positive effect on starvation survival. To the contrary, the current study provides a strong evidence for the benefits of methoprene application and protein incorporation into the adult diet of sterile males. Treated males achieve higher sexual success, reach sexual development several days earlier, and are therefore much closer to sexual maturity when released in SIT action programmes after being held in the fly emergence and release facility for a post-emergence feeding duration of at least 3 days.

The effect of access to dietary protein (P) (hydrolyzed yeast) and/or treatment with a juvenile hormone analogue, methoprene (M), (in addition to sugar and water) on male aggregation (lekking) behaviour and mating success was studied in a laboratory strain of the melon fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae). Six-day-old males were treated with (1) protein and methoprene (M+P+), (2) only protein (M−P+), or (3) only methoprene (M+P−), and compared with 14-day-old sexually mature untreated males (M−P−). The lekking behaviour of the four groups of males when competing for virgin sexually mature females (14 –16 days old) was observed in field cages. The following parameters were measured at male aggregations: lek initiation, lek participation, males calling, male–male interaction, female acceptance index, and mating success. For all these parameters, the M+P+ males significantly outperformed the other males. Moreover, for all parameters, there was a similar trend with M+P+ > M−P+ > M−P− > M+P−. More M+P+ males called and initiated and participated in lek activities than all other types of male, which resulted in higher mating success. They had also fewer unsuccessful copulation attempts than their counterparts. Whereas treatment with methoprene alone had a negative effect in young males with only access to sugar, access to dietary protein alone significantly improved young male sexual performance; moreover, the provision of methoprene together with protein had a synergistic effect, improving further male performance at leks. The results are of great relevance for enhancing the application of the sterile insect technique (SIT) against this pest species. The fact that access to dietary protein and treatment of sterile males with methoprene improves mating success means that SIT cost-effectiveness is increased, as more released males survive to sexual maturity.

The codling moth Cydia pomonella (Linnaeus) (Lepidoptera: Tortricidae) is a serious pest of pome fruit worldwide and the sterile insect technique (SIT) provides an environmentally acceptable approach for its control. As the pest is present in both the southern and northern hemispheres it would be possible for a rearing facility in the northern hemisphere to supply sterile moths to an SIT programme in the southern hemisphere during the northern winter and vice versa. This could greatly improve the economics of moth production and the running costs of rearing facilities. However in order to develop this concept, it is important to assess if populations of codling moth from different geographical regions share mating compatibility. Twelve different laboratory and field populations from both hemispheres were sampled and field cage bisexual mating compatibility tests were carried out between selected combinations. The index of sexual isolation (ISI) and the female and male relative performance index (FRPI and MRPI, respectively) were calculated for each mating combination. In only two of the combinations was there a slight but significant deviation from random mating. There were also some significant differences in mating duration between the homotypic matings and the duration of a particular homotypic mating seemed to depend on the origin of the other population in the cage. It was concluded that there exist no barriers to mating between populations of codling moth from many parts of the world and that it would be feasible for sterile moths to be shipped from one rearing facility to SIT programmes in other parts of the world.

Results of a study of the inheritance and linkage relationships of eye-color mutations in the Mexican fruit fly, Anastrepha ludens (Loew) (Diptera: Tephritidae), are presented. The mutations white eyes (we) and yellow eyes (ye) are recessive and autosomal, whereas Red eyes (Re) and Violet eyes (Ve) are dominant, and the latter is homozygous lethal. The genes we and ye showed epistatic interaction, the first with ye, Re, and Ve, and the second with Re. The results of the various crosses suggest that only Ve and ye are linked, so the linkage groups have been designated as A- we, B- Ve-ye, and C- Re. Study of these mutants in A. ludens will serve as the basis for the development of a genetic map for this species. The mutations also will be useful for the development of a genetic-sexing method.

Many species of tsetse flies are infected by a virus that causes salivary gland hypertrophy (SGH) and the virus isolated from Glossina pallidipes (GpSGHV) has recently been sequenced. Flies with SGH have a reduced fecundity and fertility. To better understand the impact of this virus in a laboratory colony of G. pallidipes , where the majority of flies are infected but asymptomatic, and to follow the development of SGH in the offspring of symptomatic infected flies, we examined the progeny of tsetse flies reared under different conditions. The results show that the progeny of asymptomatic parents did not develop SGH, while the progeny of symptomatic female flies mated with asymptomatic males developed a high rate of SGH (65% in male and 100% in females) and these flies were sterile. Stress in the form of high fly density in holding cages (180 flies/cage) and high temperature (30 °C) in the holding room did not affect the prevalence of the SGH. The virus is excreted in the saliva and there is a strong correlation between the infection status (negative, slight or strong by PCR) and the numbers of virus particles released into the blood on which the flies were fed. On average, around 10 2 and 10 7 virus particles were found in the blood after feeding asymptomatic or symptomatic infected flies respectively. Feeding the flies on new blood at every feed for three generations caused a significant reduction in the virus copy number in these flies when compared with the virus copy number in flies fed under the normal feeding regime. The results of these studies allowed the initiation of colony management protocols that aim to minimize the risk of horizontal transmission and to enable the establishment of colonies with a low virus prevalence or possibly even those that are virus free.

Wolbachia are obligatory intracellular and maternally inherited bacteria that infect and spread through natural arthropod populations by inducing male-killing, feminization, parthenogenesis, and, most commonly, unidirectional and bidirectional cytoplasmic incompatibility (CI). Cytoplasmic incompatibility can be used to control natural populations of insect pests, in a way analogous to the Sterile Insect Technique (SIT), namely through the Incompatible Insect Technique (IIT). For the successful application of the IIT (based on a unidirectional CI approach) against a target species, it is essential that only males are released, as the release of females would lead to fertile matings between the released males and the released females and the establishment of a Wolbachia-carrying field population. In the present study, we describe a Wolbachia-infected line of the VIENNA 8 genetic sexing strain of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), that carries the selectable marker temperature sensitive lethal (tsl). We show that (1) transferred Wolbachia induce high levels of CI even after the temperature treatment required for the male-only production, and (2) the Wolbachia-infected genetic sexing C. capitata line can be used in cage population suppression experiments analogous to the SIT. We also discuss our results in a comparison between IIT and SIT, investigating whether irradiation and cytoplasmic factors can be combined toward the development of novel strategies for insect pest control.

If appropriately applied, biological control offers one of the most promising, environmentally sound, and sustainable control tactics for arthropod pests and weeds for application as part of an integrated pest management (IPM) approach. Public support for biological control as one of the preferred methods of managing non-indigenous and indigenous pests is increasing in many countries. An FAO/IAEA Coordinated Research Project (CRP) addressed constraints related to costly production systems for biological control agents, and the presence of accompanying pest organisms during their shipment. These constraints can be alleviated using nuclear techniques such as ionizing radiation or X-rays to reduce production and handling costs (e.g., by expanding the period of host suitability, increasing shelf life, avoiding unnecessary sorting steps before shipment, etc.), and to eliminate the risk of shipping fertile host or prey pest individuals or other hitchhiking pests. These nuclear techniques can also help ...

It has long been proposed that the nominal species Anastrepha fraterculus is a species complex and earlier studies showed high levels of pre-zygotic isolation between two laboratory strains from Argentina and Peru. Further experiments were carried out on the same populations and on their reciprocal hybrids, including pre- and post-zygotic isolation studies, pheromone analysis, and mitotic and polytene chromosome analysis. A high level of pre-zygotic isolation had been maintained between the parental strains despite 3 years of laboratory rearing under identical conditions. The level of pre-zygotic isolation was reduced in matings with hybrids. There were also differences in other components of mating behaviour. There were quantitative and qualitative differences in the sex pheromone of the two strains with the hybrids producing a mixture. The pre-zygotic isolation barriers were complemented by high levels of post-zygotic inviability and sex ratio distortion, most likely not due to Wolbachia, although there was evidence of some cytoplasmic factor involved in sex ratio distortion. Analysis of polytene chromosomes revealed a high level of asynapsis in the hybrids, together with karyotypic differences between the parental strains. The combined results of the present study indicate that these two strains belong to different biological entities within the proposed A. fraterculus complex.

Food-based attractants incorporating an insecticide are an important component of area-wide control programmes for the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae). This study was carried out to understand the feeding mechanism of adults of this species. Mouthparts of C. capitata are similar in general structure to those of another Tephritid genus, Bactrocera, and have specific structural modifications that determine what adult flies can ingest. The labellum has a series of fine tube-like structures, called pseudotracheae, on its inner surface. Each pseudotrachea leads from the outer margin of the labellum and ends at the prestomum to the oral opening. The pseudotracheae contain fine micropores about 0.5µm in size. During feeding, the oral opening is never exposed to the feeding substrate but the portions of the opposing labellar lobes proximal to the oral opening are flexed against each other and distal portions of the opposing labellar lobes are opened and pressed flat against the feeding substrate or surface. The prestomal spines at the base of each pseudotrachea interlock to form a barrier across the oral opening. Thus entry of large particles directly into the crop and gut through the oral opening is prevented by flexure of the opposing labellar lobes against each other and the interlocking prestomal spines across the oral opening. Only liquids and suspended particles less than 0.5µm in size are sucked through the micropores into the lumen of the pseudotracheae and then pass into the food canal and into the crop and gut. The pseudotracheae of adult C. capitata, particularly along the middle portion of the labellum, have prominent blade-like projections that Bactrocera do not have. These projections are probably an ancestral condition as they were not observed to use them to abrade the plant or feeding surface as has been reported for species in the Tephritid genus, Blepharoneura.

Genetic modification (GM) of mosquitoes (which renders them genetically modified organisms, GMOs) offers opportunities for controlling malaria. Transgenic strains of mosquitoes have been developed and evaluation of these to 1) replace or suppress wild vector populations and 2) reduce transmission and deliver public health gains are an imminent prospect. The transition of this approach from confined laboratory settings to open field trials in disease-endemic countries (DECs) is a staged process that aims to maximize the likelihood of epidemiologic benefits while minimizing potential pitfalls during implementation. Unlike conventional approaches to vector control, application of GM mosquitoes will face contrasting expectations of multiple stakeholders, the management of which will prove critical to safeguard support and avoid antagonism, so that potential public health benefits can be fully evaluated. Inclusion of key stakeholders in decision-making processes, transfer of problem-ownership to DECs, and increased support from the wider malaria research community are important prerequisites for this. It is argued that the many developments in this field require coordination by an international entity to serve as a guiding coalition to stimulate collaborative research and facilitate stakeholder involvement. Contemporary developments in the field of modern biotechnology, and in particular GM, requires competencies beyond the field of biology, and the future of transgenic mosquitoes will hinge on the ability to govern the process of their introduction in societies in which perceived risks may outweigh rational and responsible involvement.

artículo (arbitrado)--Universidad de Costa Rica. Escuela de Biología, 2007 If species-specific male genitalia are courtship devices under sexual selection by cryptic female choice, then species-specific aspects of the morphology and behaviour of male genitalia should often function to stimulate the female during copulation. The morphology and behaviour of the complex, species-specific male genitalia of the tsetse fly, Glossina pallidipes Austen, were determined from both direct observations and dissections of flash-frozen copulating pairs; and we found that some male genitalic traits probably function to stimulate the female, while others function to restrain her. The male clamps the ventral surface of the female’s abdomen tightly with his powerful cerci. Clamping does not always result in intromission. Clamping bends the female’s body wall and her internal reproductive tract sharply, posteriorly and dorsally, and pinches them tightly. Males performed sustained, complex, stereotyped, rhythmic squeezing movements with his cerci that were not necessary to mechanically restrain the female and appeared instead to have a stimulatory function. Six different groups of modified setae, on and near the male’s genitalia, rub directly against particular sites on the female during squeezing. The designs of these setae correlate with the force with which they press on the female and the probable sensitivity of the female surfaces that they contact. As expected under the hypothesis that these structures are under sexual selection by female choice, several traits suspected to have stimulatory functions have diverged in G. pallidipes and its close relative, G. longipalpis. Additional male non-genitalic behaviour during copulation, redescribed more precisely than in previous publications, is also likely to have a courtship function. The elaborate copulatory courtship behaviour and male genitalia may provide the stimuli that previous studies showed induce female ovulation and resistance to remating. Universidad de Costa Rica UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biología

The papers presented in this issue are focused on developing and validating procedures to improve the overall quality of sterile fruit flies for use in area-wide integrated pest management (AW-IPM) programs with a sterile insect technique (SIT) component. The group was coordinated and partially funded by the Joint FAO/IAEA Programme of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency, Vienna, Austria, under a five-year Coordinated Research Project (CRP) on “Quality Assurance in Mass-Reared and Released Fruit Flies for Use in SIT Programmes”. Participants in the CRP from 16 countries came from both basic and applied fields of expertise to ensure that appropriate and relevant procedures were developed. A variety of studies was undertaken to develop protocols to assess strain compatibility and to improve colonization procedures and strain management. Specific studies addressed issues related to insect nutrition, irradiation protocols, field dispersal and survival, field...

Photographic polytene chromosome maps from pupal trichogen cells of four tsetse species, Glossina austeni, G. pallidipes, G. morsitans morsitans and G. m. submorsitans were constructed and compared. The homology of chromosomal elements between the species was achieved by comparing banding patterns. The telomeric and subtelomeric chromosome regions were found to be identical in all species. The pericentromeric regions were found to be similar in the X chromosome and the left arm of L1 chromosome (L1L) but different in L2 chromosome and the right arm of L1 chromosome (L1R). The L2 chromosome differs by a pericentric inversion that is fixed in the three species, G. pallidipes, G. morsitans morsitans and G. m. submorsitans. Moreover, the two morsitans subspecies appeared to be homosequential and differ only by two paracentric inversions on XL and L2L arm. Although a degree of similarity was observed across the homologous chromosomes in the four species, the relative position of specific chromosome regions was different due to chromosome inversions established during their phylogeny. However, there are regions that show no apparent homology between the species, an observation that may be attributed to the considerable intra--chromosomal rearrangements that have occurred following the species divergence. The results of this comparative analysis support the current phylogenetic relationships of the genus Glossina.

Mating compatibility among different populations of the South American fruit sy Anastrepha fraterculus (Wiedemann) was assessed through mating tests in pairwise combinations. Screened cages, inside a greenhouse, containing Citrus limon (L.) trees were used. Mating compat- ibility was determined using the index of sexual isolation. Most of the populations were noncompatible with each other and thus sexually isolated. Of these, Tucuman (Argentina) and Piracicaba (Brazil) populations showed a lower degree of isolation, whereas the other tested combinations were highly isolated. Full mating compatibility was detected only between two Argentinean (Concordia and Tucuman) and two Peruvian populations (La Molina and Piura La Molina). Flies were sexually active at different times: Tucuman, Concordia, and Piracicaba populations presented an early morning peak, La Molina and Piura La Molina were active around midday, and Ibague (Colombia) were active late in the afternoon. Manipulation of light phase conditions to match the times of maximum sexual activity did not increase the compatibility between La Molina and Tucuman. Based on these behavioral results, which conÞrm morphometric, genetic, and other evidence, the taxonomic revision of this cryptic species complex is warranted. One practical implication is that colonies of this pest to be used in any sterile insect technique approach should be derived from the target population or from a compatible population. Regional efforts should be initiated to determine the distribution of each subgroup and their relationship with each other in terms of compatibility.

Implementation of the sterile insect technique for tsetse (Glossina spp.) requires that only sterile male insects be released; thus, at some stage of the fly production process the females have to be removed. A further constraint in the use of the sterile insect technique for tsetse is that the females are needed for colony production and hence, a non-destructive method of sex separation is required. In most tsetse sterile insect technique programmes thus far, females have been eliminated from the released material by hand-separation of chilled adults. Using near-infrared (NIR) spectroscopy, significant differences have been found between the spectra for the pupae of male and female G. pallidipes Austen. Significantly, the differences appear to be maximized 4-5 days before emergence of the adults. Tsetse fly pupae up to five days before emergence can be sexed with accuracies that generally range from 80 to 100%. This system, when refined, will enable effective separation of male and female pupae to be carried out, with emerged females being returned to the colony and males being irradiated and released. If separation can be achieved five days before emergence, this will also enable irradiated male pupae to be shipped to other destinations as required. Other Diptera were evaluated using this system but had lower classification accuracies of 50-74%. This may be due to the difference in reproductive physiology between these different fly groups.

A dominant mutation, Sergeant (Sr2), which affects expression of a third stripe on the abdomen of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann), was recently isolated and the results of an extended genetic analysis are reported here. In addition, field cage data are presented on the mating competitiveness of strains carrying this mutation, including a genetic sexing strain (GSS). The incorporation of a phenotypic marker, such as Sr2, in a Mediterranean fruit fly GSS would complement, and could replace, the use of fluorescent dye for monitoring sterile insect technique programs and increase program efficiency by improving sterile and wild fly identification procedures. The mutation is homozygous lethal, and it is located on chromosome 5 at position 78B and 60D on the salivary and trichogen polytene maps, respectively. The development of the Sr2 GSS is described here, together with data on fitness and penetrance of the mutation. The field-cage results demonstrated 1) random mating bet...

The ability to genetically engineer insects other than Drosophila melanogaster has further extended modern genetic techniques into important insect pest species ranging from fruit fly pests of horticulture to mosquito vectors of human disease. In only a relatively short period of time, a range of transgenes have been inserted into more than 10 insect pest species. Genetic transformation of these pest species has proven to be a very important laboratory tool in analyzing gene function and effects on phenotype however the full extension of this technology into the field is yet to be realized. Here we briefly review the development of transgenic technology in pest insect species and discuss the challenges that remain in this applied area of insect genetics and entomology.

In the Mediterranean fruit fly (medfly), Ceratitis capitata (Wiedemann), exposure to α-copaene, a botanically derived male attractant, and ginger root oil (GRO), Zingiber officinale (Roscoe), which contains α-copaene, increased the mating success of wild males, and GRO enhanced mating competitiveness of mass-reared males from a bisexual, mass-reared strain. The present study extends this research by examining the effects of GRO exposure on the mating success of mass-reared males from a genetic sexing strain based on a temperature sensitive lethal (tsl) mutation. Such strains are currently used for nearly all sterile insect technique (SIT) programs for this insect. In addition, potential negative effects of GRO exposure on male survival and female remating propensity were investigated. Following exposure to GRO, males from the tsl mass-reared strain showed enhanced mating performance against wild-like males from two recently established colonies. Against wild-like males from a Guatemala strain, th...

The recent success of the sterile insect technique (SIT) in eradicating Glossina austeni from Zanzibar has stimulated interest in applying this technology to control Glossina pallidipes. However, little is known about the mating behaviour of this species in relation to the development and implementation of an effective SIT programme. The effect of age on male and female receptivity to mating was evaluated together with copulation duration, sperm transfer and the growth of the accessory gland and follicle A in males and females, respectively. Females and males reached their optimal sexual receptivity 9-13 days after emergence. Mean copulation duration was 20-30 min for mature males and females. The growth of follicle A and the accessory gland (apical body) was a function of age of females and males, respectively. Ovulation was not observed in virgin females up to 15 days of age whereas mated females ovulated by day 9. Males aged 7-15 days were equally effective in inseminating. Cages of males and females of different ages were set up to monitor puparial production in relation to optimization of mass rearing. The results are discussed in relation to the development of an efficient mass rearing protocol for this species and an optimal release strategy for sterile males.

The preceding papers presented in this issue represent some of the activities of a group of researchers working on fruit fly mating behavior as it relates to the use of the Sterile Insect Technique (SIT). The group was co-ordinated and partially funded by the FAO/IAEA Joint Division of Nuclear Techniques in Food and Agriculture, Vienna Austria. A variety of approaches were used to examine lekking and courtship behavior of wild and mass-reared fruit flies including video analysis, morphometrics, physiological status, geographical variation and field cage evaluation. No major qualitative differences could be demonstrated between mass-reared males and wild males, although there were some specific changes related to mass rearing and irradiation. Many studies were carried out using field-caged host trees and the results of this work have led to the establishment of a standardized protocol that is now followed by all fruit fly programs using the SIT. Using these cage studies it was shown that there are no barriers to mating between medfly populations from many parts of the world. This information is of major relevance as it permits sterile flies to be shipped from one program to another. It also has some significance for the eventual commercialization of the SIT. The use of various compounds to improve the mating success of mass reared males could have a major impact on the efficiency of SIT programs. However, the initial experiments reported here will need to be expanded before this approach can be integrated into operational programs.

The Sterile Insect Technique (SIT) is amongst the most non-disruptive pest control methods. Unlike some other biologically-based methods it is species specific, does not release exotic agents into new environments and does not even introduce new genetic material into existing populations as the released organisms are not self-replicating. However, the SIT is only effective when integrated on an areawide basis, addressing the total population of the pest, irrespective of its distribution. There has been considerable progress in the development and integrated application of the SIT against the Mediterranean fruit fly (medfly), Ceratitis capitata, as reflected by operational programs for prevention, suppression and eradication of this pest. There is however, considerable scope for improving the efficiency of medfly SIT, an indispensable requirement for increased involvement of the private sector in any future application. One way to achieve this has been the development of genetic sexing strains, making it possible to release only sterile males. Another is improving sterile male performance through a better understanding of the sexual behavior of this insect. Unlike other insects for which the SIT has been successfully applied, medfly has a complex lek-based mating system in which the females exert the mate choice selecting among aggregated and displaying wild and sterile males. With the objective of developing a better understanding of medfly mating behavior, an FAO/IAEA Coordinated Research Project was carried out from 1994 to 1999. Some of the resulting work conducted during this period with the participation of research teams from ten countries is reported in this issue.

The introduction of genetic sexing strains (GSS) into medfly, Ceratitis capitata(Wiedemann), sterile insect technique (SIT) programmes started in 1994 and it was accompanied by extensive evaluation of the strains both in field cages and in open field situations. Two male-linked translocation systems, one based on pupal colour, wp, and the other based on temperature sensitivity, tsl, have been used in medfly SIT programmes and they have quite different impacts on mass rearing strategy. In strains based on tsl, female zygotes are killed using high temperature and for wpstrains, female and male pupae are separated based on their colour. In all these systems the colony females are homozygous for the mutation requiring that the mutation is not too deleterious and the males are also semi-sterile due to the presence of a male-linked translocation. Managing strain stability during large-scale mass rearing has presented some problems that have been essentially solved by selecting particular translocations for GSS and by the introduction of a filter rearing system (FRS). The FRS operates by removing from the colony any recombinant individuals that threaten the integrity of the strain. The use of GSS opens up the possibility of using the SIT for suppression as opposed to eradication and different radiation strategies can be considered. Some of the many field trials of the strains that were carried out before the strains were introduced into operational programmes are reviewed and an overview is given of their current use.

Our understanding of Glossina fuscipes fuscipes, a major vector of sleeping sickness, has been severely constrained by a lack of genetic markers for mapping and population genetic studies. Here we present 10 newly developed microsatellite loci for this tsetse species. Heterozygosity levels in Moyo, an Ugandan population, averaged 0.57, with only two loci showing very low heterozygosity. Five loci carried more than six alleles. Together with five recently published microsatellite loci, this brings the number of available microsatellite loci for this species to 15. Their availability will greatly facilitate future studies on the genetics of this important human disease vector.

Despite the liberal use of broad-spectrum insecticides to keep many insect pests of agricultural and veterinary importance at bay, food losses, both pre- and post-harvest, due to these insect pests contribute significantly to the high prevalence of undernourishment in the world. New, innovative pest control tactics and strategies are therefore needed that are both effective and not detrimental to the environment. As part of the arsenal of environmentally-friendly control tactics, the sterile insect technique (SIT) has proven to be a very effective tool against selected insect pests when used as part of an area-wide integrated pest management (AW-IPM) approach. Likewise, the use of natural enemies for augmentative or inundative biological control is now a major component of pest control in many parts of the world. Both control tactics are complementary and even synergistic under certain circumstances, but their combined use has so far not been applied on an operational scale. Ionising radiation can be readily employed to effectively and safely induce sexual sterility in insects. Although the sterile insect technique has often been associated with an eradication strategy, major advances in rearing efficiency, and improved handling and release methods, have made the use of sterile insects economically feasible for insect pest suppression, prevention or containment. Recently, more emphasis has been placed on the quality of the sterile insect once released in the field rather than mainly assessing quality in the rearing facility. This combined with other innovations such as the development of genetic sexing strains, better understanding the impact of radiation on radio-resistant species such as Lepidoptera and the development of the F1 sterility concept, advances in monitoring the induced sterility, etc. have significantly increased the efficiency of the sterile insect technique for several insect species. The action of sterile insects is inversely dependent on the density of the target population, and sterile insects have the intrinsic capacity to actively search for and mate with the last individuals of a pest population. These two characteristics make them ideal to deal with outbreaks of invasive insect pests. The use of sterile insects presents no threat to the environment, but aspects such as diet and waste disposal in large rearing facilities or bio-security in cases where the rearing facility is located in an area that is already free of the pest require the necessary attention. Ionising radiation can also be applied to greatly improve the efficiency of mass-rearing, handling and shipment of insect parasitoids and predators. Area-wide integrated pest management programmes that use sterile insects or natural enemies are complex and management-intensive, and require a management structure that is exclusively dedicated to the programme. Past and current examples have shown the enormous benefit-cost ratios that these programmes can generate and their importance for enhanced agriculture is increasing in significance.

The Oriental fruit fly, Batrocera dorsalis s.s. (Hendel) is one of the most destructive agricultural pests, belonging to a large group of difficult to distinguish morphologically species, referred as the B. dorsalis complex. We report here a cytogenetic analysis of two laboratory strains of the species and provide a photographic polytene chromosome map from larval salivary glands. The mitotic complement consists of six chromosome pairs including a heteromorphic sex (XX/XY) chromosome pair. Analysis of the polytene complement has shown a total of five polytene chromosomes (10 polytene arms) that correspond to the five autosomes. The most important landmarks of each polytene chromosome and characteristic asynapsis at a specific chromosomal region are presented and discussed. Chromosomal homology between B. dorsalis and Ceratitis capitata has been determined by comparing chromosome banding patterns. The detection of chromosome inversions in both B. dorsalis strains is shown and discussed. Our results show that the polytene maps presented here are suitable for cytogenetic analysis of this species and can be used for comparative studies among species of the Tephritidae family. They also provide a diagnostic tool that could accelerate species identification within the B. dorsalis complex and could shed light on the ongoing speciation in this complex. Polytene chromosome maps can facilitate the development of biological control methods and support the genome mapping project of the species that is currently in progress.

A simple method of marking Mediterranean fruit fly Ceratitis capitata (Wiedemann) using stable isotopes is described. This species is economically important and is a target species of many successful area-wide integrated pest management (AW-IPM) programs using the sterile insect technique (SIT). Program monitoring in the field relies on being able to accurately differentiate released sterile insects from wild insects so that estimates can be made of the ratio of sterile males to wild males. Typically, released flies are marked with fluorescent dust, which is not always reliable. The difference in isotopic signatures between wild and factory-reared populations could be a reliable and intrinsic secondary marker to complement existing marking methods. Isotopic signatures are natural differences in stable isotope composition of organisms caused by discrimination against the heavier isotopes during some biological processes. The isotopic signature of an organism is mainly dependent on what it eats; by feeding factory-reared flies isotopically different diets to those of the wild population, it is possible to intrinsically mark the flies. The majority of fruit fly species feed on C3 plants in the wild, which have a carbon isotope signature of around -28 per thousand. However, almost all mass-rearing facilities use cane sugar in the larval and adult diet, which is a C4 sugar source (with a signal of around -11 per thousand), and this could provide an easy signature to differentiate released flies from wild flies. To test this approach, samples of flies from several mass-rearing facilities and wild populations were analyzed. It was clearly shown that using C4 sugar in the larval-rearing diet was an effective and economic way of intrinsically labeling Mediterranean fruit flies, and it was possible to distinguish mass-reared from wild populations with > 95% confidence. The C4 marker was detectable and distinguishable from wild populations up to 12 d after "release." This technique could be adopted for use in any other SIT program with similar rearing protocols to Mediterranean fruit fly.

Methoprene (a mimic of juvenile hormone) treatment can reduce the time required for sexual maturation in Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) males under laboratory conditions, supporting its use as a treatment for sterile males within the context of the sterile insect technique (SIT). We evaluated sexual behaviour, mating competitiveness of methoprene-treated males, and female readiness to mate after methoprene-treatment in field cages. The study involved two strains of A. fraterculus from Argentina and Peru, which show several polymorphisms in relation to their sexual behaviour. We also analyzed whether methoprene treatment affected male and/or female behaviour in the same way in these two strains. Methoprene-treated males were equally competitive with untreated mature males, and became sexually competitive 6 days after emergence (3-4 days earlier than untreated males). In contrast, methoprene did not induce sexual maturation in females or, at least, it did not induce a higher rate of mating in 7-day-old females. These results were observed both for the Argentina and the Peru strains. Altogether, our results indicate that methoprene treatment produces sexually competitive males in field cages. In the absence of a genetic sexing system, and when sterile males and females of A. fraterculus are released simultaneously, the fact that females do not respond as do males to the methoprene treatment acts as a physiological sexing effect. Therefore, in the presence of mainly sexually immature sterile females, released sexually mature sterile males would have to disperse in search of wild fertile females, thereby greatly reducing matings among the released sterile insects and thus enhancing sterile insect technique efficiency. Fil: Segura, Diego Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina. Programme of Nuclear Techniques in Food and Agriculture; Austria Fil: Cáceres, Carlos. Programme of Nuclear Techniques in Food and Agriculture; Austria Fil: Vera, María Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Gobierno de Tucumán. Ministerio de Desarrollo Productivo. Estación Experimental Agroindustrial Obispo Colombres; Argentina Fil: Wornoayporn, Viwat. Programme of Nuclear Techniques in Food and Agriculture; Austria Fil: Islam, Amirul. Programme of Nuclear Techniques in Food and Agriculture; Austria Fil: Teal, Peter E.A.. United States Department of Agriculture. Agricultural Research Service; Argentina Fil: Cladera, Jorge Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Genética; Argentina Fil: Hendrichs, Jorge. Programme of Nuclear Techniques in Food and Agriculture; Austria Fil: Robinson, Alan S.. Programme of Nuclear Techniques in Food and Agriculture; Austria

Glossina pallidipes and Musca domestica salivary gland hypertrophy viruses (GpSGHV and MdSGHV) replicate in the nucleus of salivary gland cells causing distinct tissue hypertrophy and reduction of host fertility. They share general characteristics with the non-occluded insect nudiviruses, such as being insect-pathogenic, having enveloped, rod-shaped virions, and large circular double-stranded DNA genomes. MdSGHV measures 65×550 nm and contains a 124 279 bp genome (∼44 mol% G+C content) that codes for 108 putative open reading frames (ORFs). GpSGHV, measuring 50×1000 nm, contains a 190 032 bp genome (28 mol% G+C content) with 160 putative ORFs. Comparative genomic analysis demonstrates that 37 MdSGHV ORFs have homology to 42 GpSGHV ORFs, as some MdSGHV ORFs have homology to two different GpSGHV ORFs. Nine genes with known functions (dnapol, ts, pif-1, pif-2, pif-3, mmp, p74, odv-e66 and helicase-2), a homologue of the conserved baculovirus gene Ac81 and at least 13 virion proteins are present in both SGHVs. The amino acid identity ranged from 19 to 39 % among ORFs. An (A/T/G)TAAG motif, similar to the baculovirus late promoter motif, was enriched 100 bp upstream of the ORF transcription initiation sites of both viruses. Six and seven putative microRNA sequences were found in MdSGHV and GpSGHV genomes, respectively. There was genome. Collinearity between the two SGHVs, but not between the SGHVs and the nudiviruses. Phylogenetic analysis of conserved genes clustered both SGHVs in a single clade separated from the nudiviruses and baculoviruses. Although MdSGHV and GpSGHV are different viruses, their pathology, host range and genome composition indicate that they are related.

Publisher Summary This chapter describes sterile insect techniques (SIT). It is a biologically based method for the control of key insect pests. Wild female insects inseminated by released, radiation-sterilized males do not reproduce, and repeated releases of the sterilized insects lead to a reduction in pest population numbers. Effective control using sterile insects is achieved when they are used systematically as part of area-wide integrated pest management (AW-IPM) programs. SIT is species-specific, nonpolluting, and resistance-free. Since the original concept was developed in the United States in the 1940s, SIT has been used successfully for screwworm flies, tsetse flies, fruit flies, and moths. Technical progress in behavioral ecology, mass rearing, strain improvement, global information, positioning and monitoring systems, and aerial release, combined with economies of scale and a growing demand for pest-free and low-pesticide agricultural products in local and international trade, have increased the use of SIT in AW-IPM programs. These programs, by decreasing insecticide use, have also facilitated the use of biological control agents against secondary insect pests.

Research on sterile mosquito technology from 1955 to the 1980s provided a substantial body of knowledge on propagation and release of sterile mosquitoes. Radiation sterilisation and chemosterilisation have been used effectively to induce dominant lethality and thereby sterilise important mosquito vectors in the laboratory. Experimental releases of chemosterilised males provided complete control of Anopheles albimanus in a small breeding population (14-15 sq km) in El Salvador. Releases of radiation sterilised males failed to control either Aedes aegypti or Anopheles quadrimaculatus in the USA. Releases of radiation-sterilised and chemosterilised male Culex quinquefasciatus in the USA and India were successful in some instances. Development of genetic sexing systems for Anopheles and improved physical separation methods for Culex have made it possible to rear and release males almost exclusively (> 99%) minimizing the release of potential vectors, the females. Factors that affected efficacy in some field programmes included reduction of competitiveness by radiation, immigration of fertilized females from outside the release zones, and inability of laboratory-bred males to perform in the wild. Despite significant progress, institutional commitments to carry the process further were generally lacking in the late 1970s and until recently. Now, with renewed interest and support for further assessment of this technology, this paper summarizes the current knowledge base, prioritizes some areas of investigation, and challenges scientists and administrators to maintain an awareness of progress, remain realistic about the interpretation of new findings, and make decisions about the sterile insect technique on the basis of informed scientific documentation. Areas recommended for priority research status include the establishment of genetic sexing mechanisms that can be transferred to other mosquito species, re-examination of radiation sterilisation, aerial release technology and mass rearing.

Mosquitoes, just as other insects produced for the sterile insect technique (SIT), are subjected to several unnatural processes including laboratory colonisation and large-scale factory production. After these processes, sterile male mosquitoes must perform the natural task of locating and mating with wild females. Therefore, the colonisation and production processes must preserve characters necessary for these functions. Fortunately, in contrast to natural selection which favours a suite of characteristics that improve overall fitness, colonisation and production practices for SIT strive to maximize only the few qualities that are necessary to effectively control populations. However, there is considerable uncertainty about some of the appropriate characteristics due to the lack of data. Development of biological products for other applications suggest that it is possible to identify and modify competitiveness characteristics in order to produce competitive mass produced sterile mosquitoes. This goal has been pursued - and sometimes achieved - by mosquito colonisation, production, and studies that have linked these characteristics to field performance. Parallels are drawn to studies in other insect SIT programmes and aquaculture which serve as vital technical reference points for mass-production of mosquitoes, most of whose development occurs - and characteristics of which are determined - in an aquatic environment. Poorly understood areas that require further study are numerous: diet, mass handling and genetic and physiological factors that influence mating competitiveness. Compromises in such traits due to demands to increase numbers or reduce costs, should be carefully considered in light of the desired field performance.

International audience; Many species of tsetse flies can be infected by a virus that causes salivary gland hypertrophy (SGH) and virus isolated from Glossina pallidipes (GpSGHV) has recently been sequenced. Flies having SGH have a reduced fecundity and fertility. To better understand the impact of this virus in a laboratory colony of G. pallidipes, where the majority of flies are infected but asymptomatic, and to follow the development of SGH in symptomatic flies in relation to virus copy number, a quantitative PCR (qPCR) method was developed. The qPCR analyses revealed that in asymptomatic flies virus copy number averaged 1.68E+5, 2.05E+5 and 1.07E+7 log10 in DNA from an excised leg, salivary glands and a whole fly, respectively. In symptomatic flies the virus copy number in the same organs averaged 1.34E+7, 1.42E+10 and 1.5E+9, respectively. Despite these statistically significant differences (p much less-than 0.0001) in virus copy number between asymptomatic and symptomatic flies, there was no correlation between age and virus copy number for either sets in adult flies. A clear correlation between virus copy number in pupae and their mothers was observed. Reverse transcription quantitative PCR (RT-qPCR) of the viral messenger RNA encoding ODV-E66, an envelope protein, revealed a clear correlation between virus copy number and the level of gene expression with values of 2.77 log10 in asymptomatic males and 6.10 log10 in symptomatic males. Taken together these results confirm the close relationship between virus copy number and SGH syndrome. They demonstrate the vertical transmission of GpSGHV from mother to progeny, and suggest that the development of SGH may be correlated to the virus copy number acquired by the larva during its intra-uterine development.

Since 1982 when transgenesis of Drosophila melanogaster splashed onto the scientific scene, 1,2 members of the vector biology community (e.g., refs. 3, 4) and international public health organization5 have recognized the potential utility of transgenesis to produce a modern incarnation of a historically puzzling observation: “anophelism without malaria:” The presence of anophelines but without disease. The corresponding concept among arbovirologists does not have a similarly appealing description, but the essence is the same: replacement of mosquito populations that are capable of transmitting disease with modified populations that are not. Visionary proponents argue that such a strategy is not only technically feasible, but that it leverages the power of biotechnology and a modern understanding of the means by which modified phenotypes can be spread through populations using transposable elements, cytoplasmic incompatibility, homing endonucleases, and meiotic drive. If theoretical possibilities are realized, such a vector population transformation would have minimal disruption to an ecosystem due to specific modification of only one vector/pathogen interaction and that without the use of drugs or environmentally harmful insecticides. Advocates cautiously emphasize that such applications will likely never be magic bullet solutions, and that they will be implemented only in integrated vector management programs. Nonetheless, realization of such a goal would be a remarkable demonstration of biological power for the benefit of human health.

Background Glossina fuscipes fuscipes is the major vector of human African trypanosomiasis, commonly referred to as sleeping sickness, in Uganda. In western and eastern Africa, the disease has distinct clinical manifestations and is caused by two different parasites: Trypanosoma brucei rhodesiense and T. b. gambiense. Uganda is exceptional in that it harbors both parasites, which are separated by a narrow 160-km belt. This separation is puzzling considering there are no restrictions on the movement of people and animals across this region. Methodology and Results We investigated whether genetic heterogeneity of G. f. fuscipes vector populations can provide an explanation for this disjunct distribution of the Trypanosoma parasites. Therefore, we examined genetic structuring of G. f. fuscipes populations across Uganda using newly developed microsatellite markers, as well as mtDNA. Our data show that G. f. fuscipes populations are highly structured, with two clearly defined clusters that are separated by Lake Kyoga, located in central Uganda. Interestingly, we did not find a correlation between genetic heterogeneity and the type of Trypanosoma parasite transmitted. Conclusions The lack of a correlation between genetic structuring of G. f. fuscipes populations and the distribution of T. b. gambiense and T. b. rhodesiense indicates that it is unlikely that genetic heterogeneity of G. f. fuscipes populations explains the disjunct distribution of the parasites. These results have important epidemiological implications, suggesting that a fusion of the two disease distributions is unlikely to be prevented by an incompatibility between vector populations and parasite., Author Summary The two types of sleeping sickness in West and East Africa are markedly distinct, require different treatments, and are caused by different parasites. The only country where both parasites are present is Uganda, where they are separated by a narrow 160 km disease-free belt. Because there is no restriction on the movement of humans and animals between the two disease zones, this separation is puzzling. We asked whether this disjunct distribution can be explained by variation within the tsetse fly that is largely responsible for transmitting both diseases in Uganda, Glossina fuscipes fuscipes. We therefore examined whether this tsetse subspecies is genetically uniform across Uganda. Our results indicate that G. f. fusicipes is not genetically different between the two disease zones, but there are clear genetic differences between northern and southern populations, which are separated by Lake Kyoga. Therefore, it is unlikely that variation in the tsetse fly determines the distribution of the two parasites. This implies that the two diseases may fuse in the near future, which would greatly complicate diagnosis and treatment of sleeping sickness in any potential area of overlap.

Genetic modification (GM) of mosquitoes (which renders them genetically modified organisms, GMOs) offers opportunities for controlling malaria. Transgenic strains of mosquitoes have been developed and evaluation of these to 1) replace or suppress wild vector populations and 2) reduce transmission and deliver public health gains are an imminent prospect. The transition of this approach from confined laboratory settings to open field trials in disease-endemic countries (DECs) is a staged process that aims to maximize the likelihood of epidemiologic benefits while minimizing potential pitfalls during implementation. Unlike conventional approaches to vector control, application of GM mosquitoes will face contrasting expectations of multiple stakeholders, the management of which will prove critical to safeguard support and avoid antagonism, so that potential public health benefits can be fully evaluated. Inclusion of key stakeholders in decision-making processes, transfer of problem-ownership to DECs, and increased support from the wider malaria research community are important prerequisites for this. It is argued that the many developments in this field require coordination by an international entity to serve as a guiding coalition to stimulate collaborative research and facilitate stakeholder involvement. Contemporary developments in the field of modern biotechnology, and in particular GM, requires competencies beyond the field of biology, and the future of transgenic mosquitoes will hinge on the ability to govern the process of their introduction in societies in which perceived risks may outweigh rational and responsible involvement.

Several species of tsetse flies can be infected by the Glossina pallidipes salivary gland hypertrophy virus (GpSGHV). Infection causes salivary gland hypertrophy and also significantly reduces the fecundity of the infected flies. To better understand the molecular basis underlying the pathogenesis of this unusual virus, we sequenced and analyzed its genome. The GpSGHV genome is a double-stranded circular DNA molecule of 190,032 bp containing 160 nonoverlapping open reading frames (ORFs), which are distributed equally on both strands with a gene density of one per 1.2 kb. It has a high A+T content of 72%. About 3% of the GpSGHV genome is composed of 15 sequence repeats, distributed throughout the genome. Although sharing the same morphological features (enveloped rod-shaped nucleocapsid) as baculoviruses, nudiviruses, and nimaviruses, analysis of its genome revealed that GpSGHV differs significantly from these viruses at the level of its genes. Sequence comparisons indicated that only 23% of GpSGHV genes displayed moderate homologies to genes from other invertebrate viruses, principally baculoviruses and entomopoxviruses. Most strikingly, the GpSGHV genome encodes homologues to the four baculoviral per os infectivity factors (p74 [pif-0], pif-1, pif-2, and pif-3). The DNA polymerase encoded by GpSGHV is of type B and appears to be phylogenetically distant from all DNA polymerases encoded by large double-stranded DNA viruses. The majority of the remaining ORFs could not be assigned by sequence comparison. Furthermore, no homologues to DNA-dependent RNA polymerase subunits were detected. Taken together, these data indicate that GpSGHV is the prototype member of a novel group of insect viruses.

Integrated pest management (IPM) has remained the dominant paradigm of pest control for the last 50 years. IPM has been endorsed by essentially all the multilateral environmental agreements that have transformed the global policy framework of natural resource management, agriculture, and trade. The integration of a number of different control tactics into IPM systems can be done in ways that greatly facilitate the achievement of the goals either of field-by-field pest management, or of area-wide (AW) pest management, which is the management of the total pest population within a delimited area. For several decades IPM and AW pest control have been seen as competing paradigms with different objectives and approaches. Yet, the two “schools” have gradually converged, and it is now generally acknowledged that the synthesis, AW-IPM, neither targets only eradication, nor relies only on single control tactics, and that many successful AW programmes combine a centrally managed top-down approach with a strong grassroots bottom-up approach, and that some are managed in a fully bottom-up manner. AW-IPM is increasingly accepted especially for mobile pests where management at a larger scale is more effective and preferable to the uncoordinated field-by-field approach. For some livestock pests, vectors of human diseases, and pests of crops with a high economic value and low pest tolerance, there are compelling economic incentives for participating in AW control. Nevertheless issues of free riders, public participation and financing of public goods, all play a significant role in AW-IPM implementation. These social and managerial issues have, in several cases, severely hampered the positive outcome of AW programmes; and this emphasises the need for attention not only to ecological, environmental, and economic aspects, but also to the social and management dimensions. Because globalization of trade and tourism are accompanied by the increased movement of invasive alien pest species, AW programmes against major agricultural pests are often being conducted in urban and suburban areas. Especially in such circumstances, factors likely to shift attitudes from apathy to outrage, need to be identified in the programme planning stage and mitigated. This paper reviews the evolution and implementation of the AW-IPM concept and documents its process of development from basic research, through methods development, feasibility studies, commercialization and regulation, to pilot studies and operational programmes.

Correspondance: a.m.m.abd-alla@iaea.org; A PCR based diagnostic method to detect salivary gland hypertrophy virus (SGHV) in tsetse flies is described. Two sets of primers GpSGHV1F/GpSGHV1R and GpSGHV2F/GpSGHV2R were selected from a virus-specific sequence. Both primer sets can detect specifically the virus in individual tsetse flies by generating an amplicon of 401 bp. Attempts were made to develop a simple and reliable non-destructive virus detection method in live flies. PCR reactions were performed on either crude or purified tsetse DNA from saliva and legs. While saliva can be an indicator for the presence of the virus in flies, the method is laborious. Crude extract from an excised middle leg resulted in a positive PCR reaction equivalent to crude extract from whole fly. However, sensitivity could be significantly increased when purified DNA was used as the template. In conclusion, PCR using a purified DNA template from a single tsetse leg represents an efficient, non-destructive method for virus diagnosis in live tsetse flies