Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
Mais filtros











Intervalo de ano de publicação
1.
Bull Entomol Res ; 114(1): 22-29, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38235530

RESUMO

Functional response and mutual interference are important attributes of natural enemies that should be analysed in species with the potential to be used as biological control agents in order to increase the predictive power of the possible benefits and/or consequences of their release in the field. Our main objective was to determine the functional response and mutual interference of Coptera haywardi (Oglobin), a pupal parasitoid of economically important fruit flies (Diptera: Tephritidae). The functional response of C. haywardi on A. ludens pupae corresponded to a type II model, with an attack rate of 0.0134 host pupa/h and a handling time of 1.843 h, which reveals a meticulous selection process of pupal hosts. The effect of mutual interference among foraging females was negatively correlated with increased parasitoid density in the experimental arena, showing a gradual decline in attack rate per individual female. The increase in the number of foraging females also had an impact on the number of oviposition scars per pupa and the number of immature parasitoids per dissected pupa, but not on the percentage of adult emergence or the sex ratio. Our results suggest that C. haywardi could act as a complementary parasitoid in the control of fruit fly pupae, since the random distribution of these pupae in the soil would decrease the possibility of aggregation and mutual interference between foraging females.


Assuntos
Himenópteros , Parasitos , Tephritidae , Feminino , Animais , Himenópteros/fisiologia , Pupa , Drosophila
2.
Insects ; 15(1)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38249062

RESUMO

The application of the sterile insect technique (SIT) requires the adaptation of insects to mass-rearing conditions. It is generally accepted that this adaptation may include a reduction in genetic diversity and an associated loss of desirable characteristics for the effective performance of sterile insects in the field. Here, we compare the genetic diversity of two mass-reared strains of the Mexican fruit fly, Anastrepha ludens, and a wild (WIL) population collected near Tapachula, Mexico, using seven DNA microsatellites as molecular genetic markers. The mass-reared strains were a bisexual laboratory strain (LAB) with approximately 130 generations under mass-rearing and a genetic sexing strain, Tapachula-7 (TA7), also under mass-rearing for 100 generations. Our results revealed an overall low level of genetic differentiation (approximately 15%) among the three strains, with the LAB and WIL populations being genetically most similar and TA7 most genetically differentiated. Although there were some differences in allele frequencies between strains, our results show that overall, the adaptation to mass-rearing conditions did not reduce genetic variability compared to the wild sample in terms of heterozygosity or allelic richness, nor did it appear to alter the level of inbreeding with respect to the wild populations. These results are contrary to the general idea that mass-rearing always results in a reduction in genetic diversity. Overall, our findings can contribute to a better understanding of the impact that adaptation to mass-rearing conditions may have on the genetic make-up of strains.

3.
Sensors (Basel) ; 23(22)2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-38005562

RESUMO

In radar entomology, one primary challenge is detecting small species (smaller than 5 cm) since these tiny insects reflect radiation that can be poorly observable and, therefore, difficult to interpret. After a literature search on radar entomology, this research found few works where it has been possible to sense insects with dimensions smaller than 5 cm using radars. This paper describes different methodologies to detect Mediterranean fruit flies with 5-6 mm sizes using a pulsed W-band radar and presents the experimental results that validate the procedures. The article's main contribution is the successful detection of Mediterranean fruit flies employing the shadow effect on the backscattered radar signal, achieving an 11% difference in received power when flies are present. So far, according to the information available and the literature search, this work is the first to detect small insects less than 1 cm long using a pulsed radar in W-Band. The results show that the proposed shadow effect is a viable alternative to the current sensors used in smart traps, as it allows not only detection but also counting the number of insects in the trap.


Assuntos
Insetos , Radar , Animais
4.
Insects ; 14(9)2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37754687

RESUMO

The Sterile Insect Technique (SIT), by means of sterile male releases of Anastrepha ludens (Loew), coupled with Augmentative Biological Control (ABC), by releasing the parasitoid Diachasmimorpha longicaudata (Ashmead), was evaluated in a commercial mango production area for one year. The obtained results were compared with mean fruit fly population values from two previous years without the combined use of both techniques. The treatments were: SIT + ABC, SIT, ABC, and Control, and each treatment was established in blocks of 5000 Ha separated by distances of 5-10 km. The evaluations were carried out through fruit sampling to assess percent parasitism and trapping of adult flies to obtain Flies per Trap per Day (FTD) values. The mean percentage of parasitism increased from 0.59% in the control treatment to 19.38% in the block with ABC. The FTD values decreased from ~0.129 and ~0.012 in the control block to 0.0021 in the block with SIT and ABC, representing a 98% suppression. The difference between the two periods in the control block was not significant. We conclude that the integration of both techniques resulted in an additive suppression of the pest population, supporting the use of both control techniques in an area-wide pest management context.

5.
Microorganisms ; 11(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37512856

RESUMO

Fruit flies (Diptera: Tephritidae) are serious pests that affect fruit production and marketing. Both third instar larvae and pupae are biological stages that persist in the soil until adult emergence. Entomopathogenic nematodes (ENs) are biological control agents that are used to control agricultural pests in greenhouse or field conditions. Several studies have been carried out under laboratory and field conditions showing how ENs can be applied within an area-wide integrated pest management approach to control fruit fly species in orchards and backyard fruit trees. In this review, we analyze how soil physical characteristics and biotic factors affect the performance of these biological control agents. Of the reviewed papers, more than half evaluated the influence of soil texture, humidity, temperature, and other factors on the performance of infective juveniles (IJs). Abiotic factors that significantly influence the performance of IJs are temperature, humidity, and texture. Among the biotic factors that affect IJs are fungi, bacteria, mites, insects, and earthworms. We conclude that ENs have the potential to be applied in the drip area of fruit trees that are infested by fruit flies and contribute to their suppression. This approach, in conjunction with an area-wide pest management approach, may contribute to pest suppression and increase the sustainability of agroecosystems.

6.
Sci Rep ; 13(1): 3797, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882477

RESUMO

In the sterile insect technique, it is important to measure the impact of mass-rearing and handling of sterile males to allow a successful control of the target wild population. This study evaluates the effect of pre-release chilling on the survival, escape ability, and sexual competitiveness of male Aedes aegypti. To determine survival and escape ability, mosquitoes were chilled at 4 °C using four different treatments of either one exposure (25 min) or two consecutive exposures (25 + 25 min, 25 + 50 min, 25 + 100 min). For sexual competitiveness, two different treatments were evaluated, chilling for 25 min once and twice. Results showed that the longest exposure to chilling caused a significant reduction of survival time, from 67 to 54 days. Escape ability was reduced by the first chilling from 25 to 7% and with the second chilling, it was reduced from 30 to 24% in the control to 4.9, 2.0 and 0.5% for 25, 50 and 100 min, respectively. Sexual competitiveness index was reduced from 1.16 in the control, to 0.32 and - 0.11 for treatments involving one and two chilling periods, respectively. It is recommended to increase the chilling temperature and reduce the exposure time to reduce the harmful effects on sterile males.


Assuntos
Aedes , Controle de Mosquitos , Controle Biológico de Vetores , Animais , Masculino , Temperatura Baixa
7.
Curr Microbiol ; 80(1): 26, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36474118

RESUMO

Recent advances in understanding the symbiotic interactions between bacteria and fruit flies have shown that they are relevant for mass rearing and the sterile insect technique (SIT). SIT involves mass production and release of sterile insects that would copulate with their wild conspecifics and thus decrease the population growth rate. The irradiation process used to sterilize mass-reared flies can modify the diversity and structure of the midgut bacterial communities, which could affect sterile male survival, flight capacity, and sexual competitiveness. Our aim was to compare bacterial communities in the midgut of wild and mass-reared Anastrepha obliqua (Macquart) males irradiated at 0, 60, and 80 Gy. After adult's emergence, their midguts were dissected, DNA was extracted, and high-throughput sequencing of the V3-V4 region of the 16S rDNA gene was performed. A total of 11 phyla, 17 classes, 47 families, and 52 genera of bacteria were identified. The most representative phylum was Proteobacteria and the predominant family was Enterobacteriaceae. We found that wild males had a different intestinal bacterial community from mass-reared males. In addition, irradiation at 60 and 80 Gy caused changes in the diversity and structure of the midgut microbiota of these sterile males, suggesting that mass rearing and irradiation cause artificial selection of the bacterial communities in the gut of A. obliqua males.


Assuntos
Bactérias , Masculino , Animais , Bactérias/genética
8.
J Econ Entomol ; 115(5): 1490-1498, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-35848878

RESUMO

The sterile insect technique has been used for the eradication or control of numerous tephritid fruit flies. However, mass-rearing and sterilization can affect the microbiota and sexual performance of male tephritid fruit flies. Despite the addition of postteneral protein food which contributes to the enhancement of the sexual performance of mass-reared males, in some cases, they are less competitive than their wild counterparts. Alternatively, the addition of probiotics may improve the sexual performance of mass-reared sterile males. In this study, we evaluated the effect of a postteneral Lactobacillus casei-enriched diet on the sexual competitivity, pheromone emission, and cuticular hydrocarbons of mass-reared sterile and fertile Anastrepha ludens (Loew) (Diptera: Tephritidae) males. Flies were fed either with sugar, standard diet (sugar and protein, 3:1), sugar + probiotic, or standard diet + probiotic. The addition of the probiotic improved the sexual competitivity of fertile and sterile males that were devoid of protein but led to a negative effect on males fed with a standard diet. As compared to males that were fed with the standard diet + probiotic/only sugar, the males fed with the standard diet or those fed on sugar + probiotic displayed a higher number of mating instances. Sterile males that fed on sugar + probiotic had a higher relative amount of anastrephine, epianastrephine, n-methyl octacosane, and 2-methyl triacontane than those fed on sugar only. Overall, these compounds were common in the treatments where males had the best sexual performance. Our results suggest that the probiotics offer nutritional advantages to males whose food lacks protein.


Assuntos
Probióticos , Tephritidae , Animais , Dieta , Hidrocarbonetos/farmacologia , Masculino , Feromônios/farmacologia , Probióticos/farmacologia , Comportamento Sexual Animal , Açúcares/farmacologia
9.
Acta Trop ; 233: 106573, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35768038

RESUMO

Worldwide, vector-transmitted diseases account for more than 17% of all infectious diseases and cause more than 700,000 deaths annually. The primary strategy to control the transmission of dengue, chikungunya and Zika focuses on the control of their vectors. Vector control programs depend mainly on the use of insecticides. However, these measures have failed to yield the desired results because the lack of proper control decreases their effectiveness over time. Also, the effect of insecticide use on non-target organisms, environmental contamination, and the development of insecticide resistance impose continuous challenges for insecticide-dependant control programs. The sterile insect technique, on the other hand, is a non-polluting and environment-friendly technique. The use of sterile insects is generally well established in agriculture, but human health interventions often require a consensus that combines social perceptions with scientific evidence. Factors associated with acceptance of the releases of sterile male Aedes aegypti mosquitoes were assessed with logistic regression models for two communities (Rio Florido and Hidalgo) in Tapachula, Chiapas, Mexico. The favourable opinion of the respondents about the project workers, and the fact that the releases of sterile mosquitoes would be managed by the Secretaría de Salud, were found to be factors that supported the acceptance of sterile mosquito releases. Factors associated with disapproval were community (Rio Florido and Hidalgo) and the misbelief that sterile male mosquitoes can bite. The differences observed between the communities included in this study might be the result of experiences with the releases, of social and community organisation, and of leadership by social actors.


Assuntos
Aedes , Dengue , Inseticidas , Infecção por Zika virus , Zika virus , Animais , Estudos Transversais , Humanos , Inseticidas/farmacologia , Masculino , México , Controle de Mosquitos/métodos , Mosquitos Vetores , Projetos Piloto , Infecção por Zika virus/prevenção & controle
10.
Insects ; 13(4)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35447790

RESUMO

Sterile males of Aedes aegypti were released once a week for 8 weeks to evaluate the dispersal efficiency of ground and aerial drone release methods in a rural village of 26 Ha in southern Mexico. Indoor and outdoor BG-Sentinel traps were placed in 13−16 houses distributed throughout the village. The BG traps were activated 48 h after the release of the sterile males and functioned for a 24 h period following each release. Over the 8-week period of simultaneous ground and aerial releases, an average of 85,117 ± 6457 sterile males/week were released at ground level and 86,724 ± 6474 sterile males/week were released using an aerial drone. The ground release method resulted in higher numbers of captured males (mean = 5.1 ± 1.4, range 1.1−15.7 sterile males/trap) compared with the aerial release method (mean = 2.6 ± 0.8, range 0.5−7.3 sterile males/trap) (p < 0.05). Similarly, the prevalence of traps that captured at least one sterile male was significantly higher for ground release compared to the aerial release method (p < 0.01). The lower numbers of sterile males captured in the aerial release method could be due to mortality or physical injury caused by the chilling process for immobilization, or the compaction of these insects during transport and release. However, aerial releases by a two-person team distributed insects over the entire village in just 20 min, compared to ~90 min of work for a five-person team during the ground release method. Ground release also resulted in higher aggregations of males and some villagers reported feeling discomfort from the presence of large numbers of mosquitoes in and around their houses. We conclude that modifications to the handling and transport of sterile males and the design of containers used to store males are required to avoid injury and to improve the efficiency of aerial releases for area-wide SIT-based population suppression programs targeted at mosquito vectors of human disease.

11.
Bull Entomol Res ; 112(2): 253-260, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34530939

RESUMO

Knowledge on reproductive strategies and host use in insect parasitoids is fundamental for biological control purposes. Superparasitism and multiparasitism, oviposition in a previously parasitized host by a female of the same or different species, respectively, may impact pest management decisions. Our objective was to determine the occurrence of superparasitism and multiparasitism in three species of native larval-pupal solitary endoparasitoids that attack Anastrepha Shiner species (Diptera: Tephritidae) in the Neotropical region, and the possible effect on offspring fitness parameters. Doryctobracon crawfordi (Viereck), Utetes anastrephae (Viereck), and Opius hirtus (Fischer) occur in sympatry in Mexico, and are currently under consideration for use as biocontrol agents. Experiments were conducted under laboratory conditions with females acting alone (self-superparasitism), females in groups of the same species (conspecific superparasitism), and females in mixed groups (multiparasitism). Our results showed that self-superparasitism is an uncommon strategy in the three native species and is rare under conditions of intraspecific competition. In the case of multiparasitism, a higher number of immature stages of U. anastrephae was observed, compared to those of D. crawfordi and O. hirtus. However, it is not clear yet if this was due to some adult female trait or to the competitive ability of the larvae. We conclude that most females of the native species studied appeared to avoid superparasitism, specifically when acting alone, suggesting a high discrimination ability, which is probably a result of a close relationship and evolutionary history with Anastrepha hosts.


Assuntos
Tephritidae , Vespas , Animais , Feminino , Larva , Pupa , Reprodução
12.
Insects ; 12(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33567551

RESUMO

The sterile insect technique may prove useful for the suppression of mosquito vectors of medical importance in regions where arboviruses pose a serious public health threat. In the present study, we examined the effects of sterilizing irradiation doses across different ratios of fertile:irradiated males on the mating competitiveness of Ae. aegypti and Ae. albopictus under laboratory and field-cage conditions. For both species, the percentage of females inseminated and the number of eggs laid over two gonotrophic cycles varied significantly in mating treatments involving 1:1, 1:5, and 1:10 fertile:irradiated males compared to controls of entirely fertile or entirely irradiated males but was not generally affected by the irradiation dose. Egg hatching was negatively affected in females exposed to increasing proportions of irradiated males in both laboratory and field cages. Male competitiveness (Fried's index) values varied from 0.19 to 0.58 in the laboratory and were between 0.09 and 1.0 in field cages, depending on th species. Competitiveness values were negatively affected by th eirradiation dose in both species under field-cage conditions, whereas in the laboratory, Ae. albopictus was sensitive to the dose but Ae. aegypti was not. In general, male competitiveness was similar across all mating regimes. Most importantly, induced egg sterility was positively correlated with the proportion of irradiated males present in the mating treatments, reaching a maximum of 88% under field-cage conditions for both Ae. aegypti and Ae. albopictus males treated with 50 and 40 Gy irradiation, respectively. These results indicate that sterile males produced at our facility are suitable and competitive enough for field pilot SIT projects and provide guidance to decide the optimal sterile:fertile ratios.

13.
Insects ; 12(1)2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33440870

RESUMO

Indoor and outdoor ovitraps were placed in 15 randomly selected houses in two rural villages in Chiapas, southern Mexico. In addition, ovitraps were placed in five transects surrounding each village, with three traps per transect, one at the edge, one at 50 m, and another at 100 m from the edge of the village. All traps were inspected weekly. A transect with eight traps along a road between the two villages was also included. Population fluctuations of Aedes aegypti and Ae. albopictus were examined during 2016-2018 by counting egg numbers. A higher number of Aedes spp. eggs was recorded at Hidalgo village with 257,712 eggs (60.9%), of which 58.1% were present in outdoor ovitraps and 41.9% in indoor ovitraps, compared with 165,623 eggs (39.1%) collected in the village of Río Florido, 49.0% in outdoor and 51.0% in indoor ovitraps. A total of 84,047 eggs was collected from ovitraps placed along transects around Río Florido, compared to 67,542 eggs recorded from transects around Hidalgo. Fluctuations in egg counts were associated with annual variation in precipitation, with 2.3 to 3.2-fold more eggs collected from ovitraps placed in houses and 4.8 to 5.1-fold more eggs in ovitraps from the surrounding transects during the rainy season than in the dry season, respectively. Aedes aegypti was the dominant species during the dry season and at the start of the rainy season in both villages. Aedes albopictus populations were lower for most of the dry season, but increased during the rainy season and predominated at the end of the rainy season in both villages. Aedes albopictus was also the dominant species in the zones surrounding both villages. The numbers of eggs collected from intradomiciliary ovitraps were strongly correlated with the numbers of eggs in peridomiciliary ovitraps in both Río Florido (R2 adj = 0.92) and Hidalgo (R2 adj = 0.94), suggesting that peridomiciliary sampling could provide an accurate estimate of intradomiciliary oviposition by Aedes spp. in future studies in these villages. We conclude that the feasibility of sterile insect technique (SIT)-based program of vector control could be evaluated in the isolated Ae. aegypti populations in the rural villages of our baseline study.

14.
Insects ; 11(11)2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33227892

RESUMO

Knowledge of the influence of evolutionary factors that promote either the differentiation or cohesion of pest insect populations is critical for the improvement of control strategies. Here, we explore the extent to which genetic differentiation occurs between populations of the Mexican fruit fly, Anastrepha ludens, in association with four plant hosts (Citrus sinensis, C. paradisi, Mangifera indica and Casimiroa edulis) in the Soconusco region of Chiapas (Mexico). Using variants from six enzymatic loci, we obtained measures of genetic diversity for three sample arrangements: (1) by sex per locality, (2) by locality and (3) by host. The extent of genetic differentiation in populations was assessed using the Analyses of Molecular Variance (AMOVA) method for each array of samples, and moderate to high levels of genetic variation were observed between the sexes, as well as among localities and host plants. A Bayesian approach was then used to assess any population structure underlying the genetic data we obtained, but this analysis showed no significant structuring due to locality or host plant. We also considered whether the observed genotypic frequencies in male and females matched those expected under a hypothesis of random mating. Here we found significant deviations from expected genotypic frequencies, suggesting that sexual selection is acting on these populations. Overall, our results indicate that sexual selection, along with the presence of some heterogeneity in environments provided by both geographical factors and availability of host plants, has influenced the evolution of pest populations in this region of Mexico. Implications for area-wide pest management strategies are discussed.

15.
J Med Entomol ; 57(3): 824-829, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-31808821

RESUMO

The Sterile Insect Technique (SIT) is a pest control method where large numbers of sterile males are released to induce sterility in wild populations. Since a successful SIT application depends on the released sterile males being competitive with wild males, standard quality control tests are a necessary component of any SIT program. Flight ability (ability to fly out from a device) is a reliable indicator of insect quality. Based on previous studies, we developed four new tubular devices constructed with locally available materials to explore their potential as flight test devices for Aedes aegypti (L.) mass-reared males. Males were allowed to fly upwards through a vertical tube, the ones that flew out were considered successful. The effect of male age (0 to 21 d old), test time interval (30 min to 24 h), and the design of the device (40 and 80 cm height and 2 and 3.5 cm diameter) were evaluated. Our devices determined differences in the flight ability of Ae. aegypti males of different ages. During the first minutes, more old males escaped than young males in three out of four types of devices. However, young males reached higher rates of escape in all cases after 24 h. For standard quality control tests, we recommend testing 2- to 3-d-old sexually mature males in the high and narrow device (80 × 2 cm). Further observations for time intervals between 1 and 5 h might be performed to decide the shortest and more representative interval to use.


Assuntos
Aedes/fisiologia , Voo Animal , Controle de Mosquitos/métodos , Controle Biológico de Vetores/métodos , Comportamento Sexual Animal , Fatores Etários , Animais , Masculino , Controle de Mosquitos/instrumentação , Controle Biológico de Vetores/instrumentação , Reprodução
16.
PLoS One ; 14(2): e0212520, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30779779

RESUMO

The sterile insect technique (SIT) may offer a means to control the transmission of mosquito borne diseases. SIT involves the release of male insects that have been sterilized by exposure to ionizing radiation. We determined the effects of different doses of radiation on the survival and reproductive capacity of local strains of Aedes aegypti and Ae. albopictus in southern Mexico. The survival of irradiated pupae was invariably greater than 90% and did not differ significantly in either sex for either species. Irradiation had no significant adverse effects on the flight ability (capacity to fly out of a test device) of male mosquitoes, which consistently exceeded 91% in Ae. aegypti and 96% in Ae. albopictus. The average number of eggs laid per female was significantly reduced in Ae. aegypti at doses of 15 and 30 Gy and no eggs were laid by females that had been exposed to 50 Gy. Similarly, in Ae. albopictus, egg production was reduced at doses of 15 and 25 Gy and was eliminated at 35 Gy. In Ae. aegypti, fertility in males was eliminated at 70 Gy and was eliminated at 30 Gy in females, whereas in Ae. albopictus, the fertility of males that mated with untreated females was almost zero (0.1%) in the 50 Gy treatment and female fertility was eliminated at 35 Gy. Irradiation treatments resulted in reduced ovary length and fewer follicles in both species. The adult median survival time of both species was reduced by irradiation in a dose-dependent manner. However, sterilizing doses of 35 Gy and 50 Gy resulted in little reduction in survival times of males of Ae. albopictus and Ae. aegypti, respectively, indicating that these doses should be suitable for future evaluations of SIT-based control of these species. The results of the present study will be applied to studies of male sexual competitiveness and to stepwise evaluations of the sterile insect technique for population suppression of these vectors in Mexico.


Assuntos
Aedes/efeitos da radiação , Fertilidade/efeitos da radiação , Controle de Mosquitos/métodos , Animais , Infertilidade , Insetos , Masculino , México , Mosquitos Vetores , Doses de Radiação , Radiação Ionizante , Dosagem Radioterapêutica , Comportamento Sexual Animal/efeitos da radiação , Esterilização Reprodutiva/métodos
17.
PLoS One ; 13(12): e0207999, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30513101

RESUMO

The transgenic strain of the Mediterranean fruit fly (medfly), Ceratitis capitata (Wied.) VIENNA 8 1260, developed from the classical genetic sexing strain VIENNA 8, has two molecular markers that exhibit red fluorescence in the body and green fluorescence in testicles and sperm. These traits offer a precise tool to discriminate between mass-reared sterile males and wild fertile males, and they could potentially increase the effectiveness of control programs for this pest. To assess the risk of horizontal transfer of the fluorescence transgenes in natural ecosystems, we used the VIENNA 8 1260 strain and the medfly parasitoid Fopius ceratitivorus. The fluorescence signal and the inheritance of the fluorescence gene markers were monitored for over 16 generations (about two years) in both species using fluorescence microscopy and a PCR-based assay. The PCR analysis was performed in four independent laboratories. Both fluorescence microscopy and PCR analysis indicated that no horizontal gene transfer of the DsRed transgene occurred during 16 generations of medfly parasitoid rearing under experimental conditions.


Assuntos
Animais Geneticamente Modificados/genética , Ceratitis capitata/genética , Transferência Genética Horizontal , Interações Hospedeiro-Parasita/genética , Himenópteros/genética , Animais , Animais Geneticamente Modificados/parasitologia , Ceratitis capitata/parasitologia , Feminino , Masculino , Controle Biológico de Vetores/métodos , Transgenes/genética
18.
Arch Insect Biochem Physiol ; 99(4): e21513, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30387887

RESUMO

In this study cuticular hydrocarbons (CHCs) were characterized from wings of individual unmated males of different Anastrepha ludens (Loew) mass-reared strains of different ages (3 and 19-day-old): (a) a standard mass-reared colony (control), (b) a genetic sexing strain, (c) a selected strain, (d) a hybrid strain, and (e) wild males. We found that the hydrocarbon profiles in all males included two n-alkanes, five monomethyl alkanes, and two alkenes. CHCs ranged from C26 to C31 . The most prominent peaks were 2-methyloctacosane (2-Me-C28), n-nonacosene (C29:1), 2-methyltriacontane (2-Me-C30), and n-hentriacontene (C31:1). Significant variations in the CHC amounts of the mass-reared strains were observed from Day 9 and thereafter. Comparison of CHCs using multivariate and canonical analyses across ages and among mass-reared strains and wild males revealed qualitative and quantitative differences. The relative amounts of C29:1 and 2-Me-C30 were significantly higher across age groups in the mass-reared strains than those in the wild males. In contrast, amounts of n-nonacosane (C29) significantly increased in wild males as they aged. Through statistical analyses, we inferred that CHC amounts vary with age. Wild males differed significantly from the mass-reared strains in the amount of C29, and the genetic sexing strain Tap-7 had significantly higher values for 2-methylhexacosane (2-Me-C26). In contrast the selected and control strain differed from the other strains in amounts of C29:1 and 2-Me-C30. We suggest that differential profiles in hydrocarbon composition among the strains may be mainly due to environmental pressures.


Assuntos
Envelhecimento/fisiologia , Hidrocarbonetos/metabolismo , Tegumento Comum/fisiologia , Tephritidae/fisiologia , Animais , Hidrocarbonetos/química , Masculino , Tephritidae/classificação , Tephritidae/crescimento & desenvolvimento
19.
J Econ Entomol ; 111(4): 1711-1715, 2018 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-29868713

RESUMO

Despite their relevant contribution to the conservation of tropical ecosystems and crop productivity through pollination, the stingless bees (Apidae: Meliponini) can be considered a group of neglected species in the assessment of pesticides upon nontarget organisms. In this article, we evaluated the effect of aerial sprays of the spinosad-based fruit fly toxic bait GF-120 upon colonies of the stingless bee Scaptotrigona mexicana Guérin (Hymenoptera: Apidae), an economically important and abundant species in some landscapes of Mexico, located in mango orchards. Colonies of the honey bee Apis mellifera L. (Hymenoptera: Apidae) were used for comparison. Eight colonies (four of A. mellifera and four of S. mexicana) were moved into each of two mango orchards, one was used as a control, with no insecticide application, and other received five weekly aerial sprays of GF-120. Foraging activity and strength of colonies of both species were measured nine times over the fruiting season, previous, during and after insecticide application. We did not find a significant difference in foraging activity and strength between exposed and control colonies of A. mellifera during the observation period. However, colonies of S. mexicana seemed to be affected by the exposure, as revealed by a reduction in colony strength. However, 1 yr later, with no insecticide applications, the colonies of both species were evaluated and found to be in good conditions. Our results showed that weekly aerial sprays of GF-120 are unlikely to generate acute poisoning in both species, even if in acute toxicity tests this product has been found to be highly active.


Assuntos
Himenópteros , Animais , Abelhas , Combinação de Medicamentos , Ecossistema , Macrolídeos , México , Polinização
20.
Pest Manag Sci ; 73(10): 2105-2110, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28382747

RESUMO

BACKGROUND: Anastrepha fruit flies are considered one of the main phytosanitary problems for the fresh fruit industry in the USA, Caribbean islands and Latin America. Since 1994, the Mexican government has implemented the National Fruit Fly Program using an area-wide integrated pest management approach. In this paper, we evaluate the effectiveness of mass trapping and compare it with ground GF-120 spraying against Anastrepha obliqua and Anastrepha ludens populations in mango cv. Ataulfo orchards. RESULTS: Multilure® traps baited with Ceratrap® or Biolure® captured significantly more fruit flies than Captor 300 in field cage tests. Mass trapping and ground GF-120 spray significantly suppressed fruit fly populations compared with untreated plots. In Multilure traps placed in untreated plots, we captured significantly more fruit flies than in treated plots with mass trapping or GF-120 sprays. Plots treated with either mass trapping or GF-120 sprays reduced the percentage of infested fruit significantly compared with untreated plots. There was no difference between mass trapping and GF-120 ground bait spraying. CONCLUSION: Our results demonstrate that mass trapping was as effective as GF-120 ground spraying for the control of fruit flies in mango cv. Ataulfo orchards. The suppression effect of mass trapping was similar to GF-120 ground bait spraying. © 2017 Society of Chemical Industry.


Assuntos
Controle de Insetos , Tephritidae , Animais , Produtos Agrícolas/crescimento & desenvolvimento , Feminino , Controle de Insetos/métodos , Masculino , Mangifera/crescimento & desenvolvimento , México
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA