Influência da idade do hospedeiro e da aprendizagem no comportamento quimiotáxico e no parasitismo de Trichogramma pretiosum

Abstract

ABSTRACT. Infl uence of host age and learning on chemotactic behavior and parasitism of Trichogramma pretiosum. Trichogramma pretiosum Riley, 1879 reared on Ephestia kuehniella Zeller, 1879 eggs, have been used in biological control of Spodoptera frugiperda (J. E. Smith, 1797). However, host age and experience just after emergence might have some infl uence on parasitism and parasitoid behavior. This study evaluated the infl uence of S. frugiperda host age and egg odor experience, on chemotactic behavior and parasitism of T. pretiosum. Spodoptera frugiperda eggs with 24, 48 and 72 hours were exposed to T. pretiosum females. Parasitoid time experience, in the same host, was evaluated within 1, 3, 4, 5, 6 and 24 hours, as well as, its host exposed time (1, 2, 3 and 24 hours). Chemotactic responses of T. pretiosum (experienced and inexperienced females) to S. frugiperda egg extracts were recorded in Y-tube olfactometer. We also observe parasitism rates (choice tests) in insects with and without experience. The parasitism average was higher in S. frugiperda eggs with 24 hours. Inexperienced females and those experienced for 1, 3 and 4 hours, parasitized less S. frugiperda eggs compared to those for 5, 6 and 24 hours. There was no diff erence in parasitism from females exposed for 2, 3 and 24 hours when compared to those exposed for one hour. Experienced females were more attracted to S. frugiperda eggs odor than to control (hexano). Parasitism percentage, by inexperienced parasitoids, was greater in E. kuehniella eggs (original host) than in S. frugiperda, however it was not observed in experienced females.KEYWORDS: Biological control, egg parasitoid, eggs extract.RESUMO. Trichogramma pretiosum Riley, 1879 mantido em ovos de Ephestia kuehniella Zeller, 1879, tem sido utilizado no controle biológico de Spodoptera frugiperda (J. E. Smith, 1797). No entanto, fatores como idade do hospedeiro e experiência prévia, podem infl uenciar o parasitismo e o comportamento do parasitoide. Esse estudo avaliou a infl uência da idade dos ovos e da experiência em ovos e extrato de ovos de S. frugiperda no comportamento quimiotáxico e no parasitismo de T. pretiosum. Ovos de S. frugiperda com 24, 48 e 72 horas, foram expostos a fêmeas de T. pretiosum. Também foi avaliado o tempo de experiência do parasitoide, no mesmo hospedeiro, por 1, 3, 4, 5, 6 e 24 horas, assim como, seu tempo de exposição (1, 2, 3 e 24 horas). As respostas quimiotáxicas de T. pretiosum (experiente e não experiente) em extrato de ovos de S. frugiperda foram observadas em olfatômetro tipo Y. As taxas de parasitismo foram registradas em teste de escolha, com insetos experientes e inexperientes com ovos e extrato de ovos de S. frugiperda. O parasitismo em S. frugiperda foi signifi cativamente maior em ovos com 24 horas de idade. Fêmeas inexperientes e experientes por 1, 3 e 4 horas, apresentaram uma menor taxa de parasitismo, quando comparadas a fêmeas expostas por 5, 6 e 24 horas. Não houve diferença de parasitismo em fêmeas expostas por 2, 3 e 24 horas, comparadas à...

Influência Da Idade De Ovos De Trichoplusia Ni (Lepidoptera: Noctuidae) Em Fêmeas De Trichogramma Pretiosum (Hymenoptera: Trichogrammatidae) Em Diferentes Temperaturas

“…According to age of the host egg, change in its physical and chemical characteristics is the factor that has been more influential in the development of the parasitoid, as it was demonstrated in this study. The authors Vargas et al (2017) observed similar results. However, Polanczyk et al (2007) found that T. exiguum presented a better rate of parasitism when eggs of crucifer moths had 72 hours in embryonic development.…”

“…This correlation can be found in studies by Stinguel et al (2013) between 0.82 and 1, Zuim et al (2013) between 0.57 and 0.91, where sexual ratio in M. latipes eggs presented a ratio varying from 0.82 to 1 when the parasitoid was T. pretiosum, and 0.57 and 0.91 for T. exiguum. However, Vargas et al (2017) used T. pretiosum in S. frugiperda host and the rates varied from 0.46 to 0.50.…”

Chemotaxic Responses of Anisopteromalus calandrae (Howard) (Hymenoptera: Pteromalidae) to Odors of Larvae, Pupae, and the Diet of Lasioderma serricorne (Fabricius) (Coleoptera: Ptinidae)

“…We conclude that the results of this work show that the reproductive state of males and females of A. calandrae (virgin or mated) does not affect the attractiveness to the volatile larvae or pupae with or without diet, but prior experience with the host alters the response of paired females. In applied context, the parasitoid learning could help to develop strategies for behavior manipulation and increase the impact of biological control (Meirelles et al 2009, Vargas et al 2017.…”

Chemotaxis and parasitism of the Neotropical fruit fly parasitoidGanaspis pelleranoican be altered by pre‐imaginal and imaginal conditioning to fruit volatiles

“…Although parasitoids have an innate preference for certain odors, some species can optimize foraging through learning (Turlings et al, 1993; Vargas et al, 2017; Pires et al, 2021). Learning is a change in behavior that occurs as a consequence of individual experience and may induce memory formation, i.e., the ability to encode, store, and retrieve acquired information (Kandel, 2001; Dudai, 2002).…”