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Tuta absoluta (Meyrick) is an important pest of tomato. Mass trapping of males has seldom proved an effective control measure, probably due to the pest's reproductive biology. There are few studies on female mating behaviour. For this reason, this study aimed to determine female mating frequency and its effects on reproductive output and female longevity; the effects of male mating status on female reproductive output and longevity and the fate of the spermatophore inside the bursa copulatrix. The studied population of T. absoluta mated only once a day at the beginning of the photophase, females remated frequently and can be classified as polyandrous. The refractory period of both T. absoluta males and females was very short and was not observed in many cases. The lack of refractory period could be due to the female's rapid metabolism of the spermatophore thus allowing the female to reduce the intermating interval and mate again. Remating had direct benefits for T. absoluta females increasing their fecundity, fertility and longevity. These benefits were greater when females could remate to virgin males instead of to the same male. In this species, therefore, polyandry has direct benefits for the female. The occurrence of polyandry together with other known or unknown reasons can explain the failure of control methods based on pheromones in the open greenhouses in some tomato-growing areas. [ABSTRACT FROM AUTHOR]

Edge effect tests have been used in a number of studies on obliquebanded leafroller, Choristoneura rosaceana (Harris), to test for evidence of mated female immigration into pheromone- treated orchards. This type of test compares obliquebanded leafroller presence or activity around the perimeter of an orchard against presence or activity in the interior. Higher numbers detected around the edges of an orchard would indicate higher levels of flight activity at the edge, a pattern that could be generated by high levels of immigration. Recent work has shown that the spatial distribution of recaptured obliquebanded leafroller adults released from a single location can be directionally biased, which could obscure the ability to detect an edge effect. To test this theory, data from an orchard study conducted in 1991 that found no significant edge effect was reanalyzed. When we accounted for the directional bias in the distribution of first-generation mated female moths, we found an edge effect with significantly more mated females captured in the edge traps than in the center or mid-interior traps. No edge effect was found when the directional bias was ignored. In addition, second-generation males and mated females both showed a significant edge effect that had not been detected in the original analysis, which had combined both first- and second-generation data. [ABSTRACT FROM AUTHOR]