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Doses of 40, 80, 120, and 160 Gy were applied to 5-, 6-, 7-, and 8-day-old Anastrepha obliqua larvae, which were exposed to the Neotropical-native braconids Doryctobracon crawfordi and Utetes anastrephae and the Asian braconid Diachasmimorpha longicaudata. These tests were performed to know the effect of the increase in host radiation on the emergence of the aforementioned parasitoids and the related consequences of oviposition on the host. The study was based on the fact that higher radiation doses may cause a decrease in the host immune activity. There was a direct relationship between the increase in radiation dose and the parasitoid emergence. Both, the weight and the mortality of the host larvae were not affected by radiation. Although the larval weight of the larvae was lower and the mortality was higher in the younger larvae. Both, the number of scars and immature stages per host puparium originated from the younger larvae were lower than those from older larvae. Only U. anastrephae superparasitized more at lower radiation. Superparasitism by D. longicaudata was more frequent at 160 Gy. Qualitative measurements of melanin in the larvae parasitized showed that the levels were lower with increasing radiation. As radiation doses increased, the antagonistic response of the A. obliqua larva was reduced. Host larvae aged 5- and 6-day-old irradiated at 120–160 Gy significantly improve parasitoid emergence. This evidence is relevant for the mass production of the three tested parasitoid species.

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.

Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) is a solitary parasitoid used in augmentative releases to control Tephritidae (Diptera) fruit flies of economic importance. Pre‐release process includes packing adult parasitoids in cages at high densities and expose them to a temperature of 2 ± 2 °C during 105 min. In this process, females’ antennae may be damaged resulting in a reduction in their host‐searching ability and fecundity. Here we measured, for five consecutive days after chilling, the searching ability and fecundity of parasitoids with damaged (D) and undamaged (ND) antennae compared with parasitoids that were not chilled. Female individual responses to fruit infested by Anastrepha spp. was determined in an olfactometer. Latency in the response and latency in making a choice were recorded. Additionally, groups of 30 females were used to measure their ability to find hosts in infested fruit in the laboratory. Fecundity was determined by using artificial oviposition units with Anastrepha ludens (Loew) larvae. In the olfactometer test, ND had lower response than control females during the 1st and 2nd days after chilling. However, no difference in the response was observed between ND and D and the control females on the 5th day. Additionally, chilled females showed a longer latency of response to infested fruit than females of the control treatment when tested in groups. However, after a 24–48 h period, no difference between D and ND and control females was observed. Our results showed similar searching ability and fecundity among parasitoids of the three tested conditions at individual and at group levels. We conclude that pre‐release chilling reduces female searching ability only for the first 1–2 days after chilling.

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.

To determine the natural parasitism in fruit fly populations in disturbed areas adjacent to commercial mango orchards in the states of Chiapas and Veracruz, Mexico, we recorded over one year the fruit fly-host associations, fly infestation, and parasitism rates in backyard orchards and patches of native vegetation. We also investigated the relationship between fruit size, level of larval infestation, and percent of parasitism, and attempted to determine the presence of superparasitism. The most recurrent species in trap catches was Anastrepha obliqua (Macquart), followed by Anastrepha ludens (Loew), in both study zones. The fruit infestation rates were higher in Chiapas than in Veracruz, with A. obliqua again being the most conspicuous species emerging from collected fruits. The diversity of parasitoids species attacking fruit fly larvae was greater in Chiapas, with a predominance of Doryctobracon areolatus (Szépligeti) in both sites, although the exotic Diachasmimorpha longicaudata (Ashmead) was well established in Chiapas. Fruit size was positively correlated with the number of larvae per fruit, but this relationship was not observed in the level of parasitism. The number of oviposition scars was not related to the number of immature parasitoids inside the pupa of D. areolatus emerging from plum fruits. Mass releases of Di. longicaudata seem not to affect the presence or prevalence of the native species. Our findings open new research scenarios on the role and impact of native parasitoid species attacking Anastrepha flies that can contribute to the development of sound strategies for using these species in projects for augmentative biological control.

Superparasitism refers to the action of parasitoids ovipositing eggs in hosts that are already parasitized; this inevitably results in the elimination of supernumerary larvae in solitary parasitoids. Here, we investigated superparasitism performed by two species of solitary parasitoids on the larvae of Anastrepha ludens (Loew; Diptera: Tephritidae): a native species, Doryctobracon crawfordi (Viereck; Hymenoptera: Braconidae), and an exotic species, Diachasmimorpha tryoni (Cameron; Hymenoptera: Braconidae). Tests were conducted under laboratory conditions evaluating the behaviour of females acting alone (self-superparasitism) or in groups (conspecific superparasitism). Parasitism strategies were different between these two species. In D. crawfordi, the number of first instar larvae found in each dissected host pupa was never greater than two, regardless of the number of oviposition scars observed per pupa. In contrast, there was a positive correlation between the number of oviposition scars and the number ...

Antecedentes: Dentro de los factores de riesgo para padecer hígado graso no alcohólico (HGNA) se encuentran la obesidad, el síndrome metabólico (SM) y dietas energéticamente densas. En Sonora la prevalencia de obesidad infantil es un problema de salud pública. Estudios realizados por CIAD, A.C. en escolares sonorenses muestran una población infantil con un perfil de lípidos alterado, alteraciones en glucosa, así como la existencia de SM. Objetivo: Analizar la presencia de HGNA en niños escolares sonorenses y determinar una posible asociación entre HGNA con el consumo dietario de carbohidratos simples y de grasa. Materiales y métodos: Se realizó un estudio de corte transversal en 347 niños de edad escolar en una muestra representativa del estado de Sonora. El estado de Sonora se dividió en tres zonas (norte, centro y sur), se incluyeron 6 municipios y participaron 18 escuelas primarias. Se evaluó antropometría, composición corporal, dieta, biomarcadores del metabolismo de lípidos y carbohidratos, así como la concentración de las enzimas alanina aminotransferasa y aspartato aminotransferasa (ALT y AST) indicadoras de daño hepático. Resultados: La edad promedio de la población infantil estudiada fue de 7.3 años, con sobrepeso y obesidad, masa grasa corporal elevada, así como un perfil metabólico alterado. La zona centro correspondiente al municipio de Hermosillo resultó ser la más afectada. Con los puntos de corte dados por la Organización Mundial de Gastroenterología (2012), para hacer el diagnóstico de HGNA, no fue posible diagnosticar ningún niño con la enfermedad. Sin embargo, los niños que presentaron un perfil antropométrico y metabólico alterado considerado de riesgo para HGNA, tuvieron una concentración de la enzima ALT de 17UI/L, lo que sugiere que el punto de corte sea alrededor de ésta concentración. El análisis de la dieta mostró una asociación positiva entre el consumo de azúcares simples (g) y grasa saturada (g) con el aumento de la masa grasa corporal y la circunferencia de cintura (cm), a su vez estos parámetros se relacionaron con una mayor concentración de la enzima ALT. Conclusión: Este estudio demuestra que en la zona centro del estado de Sonora se concentran los problemas de mal nutrición causados por el sobrepeso y la obesidad. Se requiere adecuar el método para confirmar el diagnóstico de HGNA a una concentración de ALT alrededor de 17UI/L, y un examen de ultrasonido hepático para confirmarlo.

Es importante determinar el contenido calorico de alimentos no-industrializados (ANI) expendidos en tiendas escolares, con la finalidad de fortalecer los programas en la lucha contra el sobrepeso y obesidad en estudiantes, por tal motivo, el objetivo de esta investigacion se centro en la cuantificacion del contenido calorico total de los ANI de mayor consumo, siendo los molletes y sandwich los alimentos preferidos por los estudiantes, de acuerdo a un estudio realizado en nueve planteles de educacion primaria, ubicados en tres diferentes zonas geograficas (sur, centro y noroeste) de Hermosillo, Sonora. Se determino el contenido calorico en molletes y sandwich por medio de calorimetria en bomba. Ambos alimentos sobrepasaron el aporte calorico recomendado por el Acuerdo Nacional para la Salud Alimentaria (ANSA, 2010). Tambien se encontraron diferencias tanto en el contenido calorico como en el tamano de los ANI, siendo la zona centro de la ciudad la que sobrepaso el estandar de calorias recomendadas (arriba de 300%). Los resultados revelan la necesidad de regular la preparacion y el tamano de las porciones en los alimentos no industrializados, ya que aportan un elevado contenido calorico, debiendo implementar mecanismos que garanticen el cumplimiento de las recomendaciones, permitiendo una facil y confiable evaluacion periodica de los mismos.