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The capacity of a parasitoid to discriminate hosts can favor the survival of its progeny as well as improve its efficacy as a biocontrol agent when it is used with another natural enemy, as this may result in greater control of the pest. Our aim was to characterize the discrimination ability of Coptera haywardi (Oglobin) (Hymenoptera: Diapriidae) females with respect to puparia of Anastrepha obliqua (Macquart) (Diptera: Tephritidae) treated with the fungus Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), under three conditions: (1) no choice, separately exposing A. obliqua puparia, treated at 0, 24, 48, or 72 h prior to exposure, to the parasitoid and without application of the fungus (absolute control); (2) with the possibility of choosing between untreated and treated puparia with the same times after fungus application; and (3) multiple choice, where parasitoids could select among puparia treated at different times. Observations were made to determine the discrimination behavior of the wasps as well as the number of ovipositions by each female parasitoid; 14 observations were made. Coptera haywardi exhibited different levels of discrimination depending on the test. In the no‐choice test, discrimination was not observed; in the two‐choice test, females significantly discriminated the puparia treated at 0, 24, and 72 h prior to exposure; and in the multiple‐choice test, females preferred the untreated puparia – behavior that was corroborated in the direct observations. Oviposition time ranged from 9 to 86 min and differences in average time among treatments were not significant. We conclude that the discrimination ability of C. haywardi allows the simultaneous use of B. bassiana, as females prefer healthy, untreated puparia without interfering with the fungus. [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]