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Copyright of Agro Productividad is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin on the development of immature stages, and survival and fecundity of Coptera haywardi (Oglobin) adults was studied under laboratory conditions. The fungus was applied as dry conidia on parasitized pupae of Anastrepha obliqua (Macquart) (Diptera: Tephritidae) and on parasitoid adults of two different age groups (1- to 4-d-old, and 5- to 10-d-old). The fungus caused no negative effects on the development of the immature stages, since there were no differences on the emergence of adults compared with the untreated control. Adults were susceptible to the fungus on both sexes and age groups. Males showed shorter lifespan than females, even in untreated individuals. Despite the increased adult mortality produced by the fungus there was no effect on fecundity during first 18 d of adult life, as the net fecundity was 26.7 and 26.3 parasitoids per female treated and untreated, respectively. Our results suggest that, given the low susceptibility of parasitized pupae and the no effect on fecundity during the first 18 d of adult life, it is possible to develop management strategies using these two natural enemies in the biological control against A. obliqua. Se estudió bajo condiciones de laboratorio el efecto del hongo entomopatógeno Beauveria bassiana (Balsamo) Vuillemin sobre el desarrollo de estados inmaduros, supervivencia y fecundidad de los adultos de Coptera haywardi (Oglobin). El hongo se aplicó como conidio seco sobre pupas de Anastrepha obliqua (Macquart) (Diptera: Tephritidae) parasitadas y en adultos de dos grupos de edad (1–4 d y 5–10 d). El hongo no ocasionó efectos negativos en el desarrollo de los estados inmaduros, dado que en la emergencia de adultos no hubo diferencias con el testigo. Ambos sexos y grupos de edades de los adultos fueron susceptibles al hongo. Los machos tuvieron una vida más corta que las hembras incluso en los individuos no tratados. La infección del hongo incrementó la mortalidad, pero no hubo efecto sobre la fecundidad durante los primeros 18 días de vida adulta, ya que la fecundidad neta fue de 26.7 y 26.3 parasitoides por hembra tratada y no tratada, respectivamente. Nuestros resultados sugieren que dada la baja susceptibilidad de la pupa parasitada y el no efecto sobre la fecundidad neta durante los primeros 18 días de vida adulta, es posible desarrollar estrategias de manejo usando estos dos enemigos naturales en el control biológico de A. obliqua. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Entomología is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tapachula-7 is a genetic sexing strain of Anastrepha ludens ( Loew) ( Diptera: Tephritidae) developed for the application of the sterile insect technique ( SIT). To improve the sexual performance of this strain, a mass-reared colony was established from males selected for their sexual competitiveness., Males from selected colonies are more sexually competitive than nonselected males. The present study aimed to analyse the demographic changes recorded in the study colony throughout four consecutive generations, comparing this colony with the parental colony and a wild strain., The results obtained showed that, in the selected strain, fecundity increased, whereas survival diminished, compared with the laboratory parental strain. The increases in fecundity rates were observed at the first generation after selection. No changes were observed in the duration of the reproductive period in the selected strain., Compared with wild flies, selected flies had lower life expectancy, earlier and shorter reproductive period, and greater daily fecundity at young ages (10-30 days), although with lower lifetime fecundity rates., The four generations of the selected colony showed similar patterns of survival and reproduction. The better mating performance and the increase in early fecundity suggest that selection could contribute to improve rearing efficiency and SIT effectiveness. [ABSTRACT FROM AUTHOR]

The sterile insect technique ( SIT) has been applied successfully for the control of several fruit fly species of economic importance. In species with lek mating systems, as in the Mexican fruit fly, Anastrepha ludens ( Loew) ( Diptera: Tephritidae) - where the variance in male mating success is high, males have to compete with other males, and where wild females are highly selective - the success of SIT depends on the sexual competitiveness of mass-reared sterile males. However, mass-rearing conditions result in selection of sexual behavioral traits that differ from wild flies, reducing mating competitiveness of sterile flies and SIT efficiency. Artificial selection in mass-rearing colonies, based on male mating success, represents an alternative to improve the sexual performance of sterile males. Here, we evaluated the effect of selection of A. ludens mass-reared males based on their mating competitiveness. Two modes of selection were compared, one single selection event on parental flies, and continuous selection along four consecutive generations. For the offspring of each treatment in each generation, we evaluated male mating success, its association with post-copulatory behavior through female remating inhibition, and life-history traits that are key for mass-rearing, such as immature survival and reproduction. Field cage mating tests revealed that wild males were more competitive than mass-reared males (selected and unselected). Although no significant differences were found between mass-reared selected and non-selected males, in the fourth generation males from the selected colonies performed better than males from the non-selected colonies and their mating competitiveness was similar to that of wild males. No consistent differences were observed in mating latency, copulation duration, or ability to inhibit female remating. Survival and fecundity decreased with increasing rearing generations, except in the colony with continuous selection where fecundity and fertility increased. [ABSTRACT FROM AUTHOR]

Toxic environmental effects of most insecticides have led to a search for bio-organic insecticides. In this study, we tested the effects of lethal and sublethal exposure to two abamectin-based insecticides (VOLIAM TARGO and LUQ-THOR) on survival, mating, and oviposition of the tephritid Anastrepha ludens (Loew). Different doses of insecticides (0.001-2.00% of the commercial products) were offered mixed with the phagostimulant bait Captor commonly used in spraying and in trapping activities for the control of flies. Both insecticides exhibited 90% killing effectiveness (Abbott index) when offered in doses between 0.02 to 2.00%. The LC50 obtained from the bioassay at 72 h after treatment was 0.003% of commercial product for TARGO and 0.008% for LUQ-THOR. Sublethal exposures to insecticides (0.003%; LC50 for TARGO and LC30 for LUQ-THOR) caused a reduction in oviposition but not in mating parameters, indicating that females were more susceptible than males to reduced doses of insecticide. The mean amount of eggs deposited 5 d after feeding on the insecticide-bait mixtures was reduced up to a third compared with the amount of eggs deposited by untreated females. Both insecticides are promising bio-organic alternatives to malathion in bait control programs against A. ludens. [ABSTRACT FROM AUTHOR]

We compared the calling and mating behavior and volatile release of wild males Anastrepha ludens (Loew) with males from 4 mass-reared strains: (i) a standard mass-reared colony (control), (ii) a genetic sexing strain (Tap-7), (iii) a colony started from males selected on their survival and mating competitiveness abilities (selected), and (iv) a hybrid colony started by crossing wild males with control females. Selected and wild males were more competitive, achieving more matings under field cage conditions. Mass-reared strains showed higher percentages of pheromone calling males under field conditions except for Tap-7 males, which showed the highest percentages of pheromone calling males under laboratory cage conditions. For mature males of all strains, field-cage calling behavior increased during the last hour before sunset, with almost a 2 fold increase exhibited by wild males during the last half hour. The highest peak mating activity of the 4 mass-reared strains occurred 30 min earlier than for wild males. By means of solid phase microextraction (SPME) plus gas chromatography-mass spectrometry (GC-MS), the composition of volatiles released by males was analyzed and quantified. Wild males emitted significantly less amounts of ( E, E)-α-farnesene but emitted significantly more amounts of ( E, E)-suspensolide as they aged than mass-reared males. Within the 4 mass-reared strains, Tap-7 released significantly more amounts of ( E, E)-α-farnesene and hybrid more of ( E, E)-suspensolide. Differences in chemical composition could be explained by the intrinsic characteristics of the strains and the colony management regimes. Characterization of calling behavior and age changes of volatile composition between wild and mass-reared strains could explain the differences in mating competitiveness and may be useful for optimizing the sterile insect technique in A. ludens. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Entomology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)