Biological and behavioral aspects of two laboratory strains of Ceratitis capitata (Diptera: Tephritidae): the influence of periodic introduction of wild flies in the colony

Abstract

ABSTRACT.The healthy maintenance of insects reared under laboratory conditions requires strategies to retain the natural characteristics of their life-histories traits. Rearing strategies include artificial selection to laboratory conditions, hybridization with compatible strains, and supplying the colony with wild individuals. We compared behavioral as well as life-history aspects of two laboratory strains of Ceratitis capitata Wiedemann (Diptera, Tephritidae) that had either been reared for 15-20 years under laboratory conditions with or without introducing wild specimens (Lab-Pop and Hybrid-pop, respectively). The parameters evaluated were: performance and food ingestion of immatures, adult size and longevity, female oviposition preference and fecundity, egg viability, and mating choice. Analyses of these parameters were conducted under laboratory rearing conditions. The largest differences observed between the two strains were related to behavioral components: food ingestion rate at the larval stage and oviposition behavior. In general, Lab-Pop individuals were less selective and more adapted to the artificial diet than Hybrid-Pop individuals (diet consumption), but there were no significant differences between the two strains in terms of percentage of emergence, egg viability, adult size, fecundity, and mating choice. It is suggested that the use of hybrid strains is more appropriate than the use of strains without the incorporation of wild individuals, especially in studies that involve behavioral parameters, as hybrid strains behave very similarly to wild populations, according our previous studies. Key words: fruit flies, laboratory rearing, feeding behavior, life history. insectos incluyen selección, hibridación con linajes compatibles y suministro a la colonia con individuos silvestres. Para investigar este último punto, comparamos los aspectos comportamentales así como los aspectos de las historias de vida de dos colonias de laboratorio de Ceratitis capitata Wiedemann (Diptera, Tephritidae) que han sido criadas entre 15 y 20 años en condiciones de laboratorio sin introducir ejemplares silvestres (Lab-Pop), o con introducciones ocasionales (Hybrid-Pop). Los parámetros evaluados fueron: el desempeño y la tasa de ingesta larval, el tamaño y la longevidad de los adultos, la preferencia de oviposición y fecundidad de la hembra, la viabilidad del huevo, y la elección para el apareamiento. Se realizaron análisis de estos parámetros bajo condiciones de cría con una dieta artificial. Las mayores diferencias entre individuos de las dos colonias se registraron en variables comportamentales: tasa de ingesta larval y comportamiento de oviposición. En general, la colonia LabPop fue menos selectiva y más adaptada a la dieta artificial que la colonia Hybrid-Pop (consumo de la dieta), pero no hubo ninguna diferencia significativa entre las dos poblaciones en el porcentaje de emergencia, la viabilidad del huevo, el tamaño de los adultos, la fecundidad, y éxito en el apareamiento. Se sugiere que el uso de colonias híbri...

Effects of domestication on quality control parameters of the Queensland fruit fly Bactrocera tryoni (Diptera: Tephritidae)

“…Reflecting the results of the present study, Meats et al (2004) found that the egg load of an old Q-fly colony was higher than that of young colonies. Increase in egg production and reduced choosiness of oviposition site has been reported in laboratory-adapted colonies of C. capitata (Bravo & Zucoloto, 1998;Elaini et al, 2020;Joachim-Bravo et al, 2009;Vargas & Carey, 1989). Positive relationship between fecundity and domestication has also been reported in fruit flies including B. oleae (Rossi) (Ahmad et al, 2016) and A. ludens Loew (Cayol, 2000;Carey et al, 2005), as well as in insects from other taxa, including sweet potato weevil, Euscepes postfasciatus (Coleoptera: Curculionidae) (Shimoji & Miyatake, 2002).…”

“…Increase in egg production and reduced choosiness of oviposition site has been reported in laboratory‐adapted colonies of C . capitata (Bravo & Zucoloto, 1998; Elaini et al, 2020; Joachim‐Bravo et al, 2009; Vargas & Carey, 1989). Positive relationship between fecundity and domestication has also been reported in fruit flies including B .…”

Quality control applications for recovering an inbred colony of Bagrada hilaris (Hemiptera: Pentatomidae)

“…Field-collected populations of insects experience genetic bottlenecks when used to establish laboratory colonies ( Boller 1972 , Hoffman and Ross 2018 ). Insects that survive colonization may not have fitness traits that were adaptive in the field, instead they become lab-adapted due to the selection pressures of their new environment ( Chambers 1977 , Joachim-Bravo et al 2009 ). They eventually tend to be less mobile ( Boller 1972 ), develop faster, and have a greater rate of reproduction than the source population ( Meats et al 2004 ).…”

“…Life-history parameters can be monitored to determine the degree of decline relative to previous time periods, particularly the proportion of mated females, pre-oviposition period, age-specific fecundity, percent egg eclosion, rate of immature development, mass or size of the insects, and ultimately the yield of viable adults ( Leppla 2009 ). At some threshold of minimal viability, the colony must be restored by adding insects from the source population with managed selection ( Joachim-Bravo et al 2009 , Sorensen et al 2012 , Hoffman and Ross 2018 ) or by replacing it entirely ( Mangan 2021 ). Adding insects without removing bottlenecks experienced by the founding population would not improve the colony.…”