Abstract
This study evaluated the rates of paralyzation, parasitism and reproductive success of Habrobracon hebetor (= Bracon hebetor), parasitoids of lepidopteran pests of stored products, under the influence of different photoperiods. Parasitoids developed during pre-imaginal stage in three different photoperiods (light/dark) 24:0, 12:12 and 0:24, and then adults from each treatment were exposed to 0, 12 and 24 hours of photophase, totalizing 9 treatments. One parasitoid couple was placed in a Petri dish containing ten larvae of last instar Ephestia kuehniella, being removed after each 24 hours and transferred to a new dish with ten larvae, until the death of the female. Number of paralyzed and parasitized larvae and number of eggs were evaluated daily. The parasitized larvae were maintained in the same conditions of photoperiods to verify the viability (%) of each development stage. The number of paralyzed larvae was always higher than parasitized with a maximum parasitism between the 2nd and 4th day of age. Accumulated parasitism reached 80% between the 6th and 8th day of age, independent of the photoperiod. The mean number of survivors at each stage of development was higher in offspring born from full photophase with an increase in the total number of eggs produced by them. However, between treatments, the final viability was not affected considering the proportion of initial oviposition. The photoperiod in adult stage did not influence the performance of H. hebetor.
Highlights
Existe uma variedade de parasitoides que são conhecidos como inimigos naturais de pragas de produtos armazenados, embora, muitas vezes, as citações limitem-se apenas à identificação do agente (Lorini et al, 2015)
Da mesma forma que o observado para H. hebetor neste estudo, Santana et al (2013) também não observaram diferenças significativas na viabilidade total entre os fotoperíodos com ou sem luz na fase adulta de T. pretiosum sobre ovos de E. kuehniella, obtendo valores de 67,5% em total fotofase e de 55,4% em total escotofase, demonstrando que, uma vez parasitados, o fotoperíodo não afeta a emergência
Conflito de Interesse: Os autores declaram não haver conflito de interesse
Summary
Existe uma variedade de parasitoides que são conhecidos como inimigos naturais de pragas de produtos armazenados, embora, muitas vezes, as citações limitem-se apenas à identificação do agente (Lorini et al, 2015). O fotoperíodo é um dos sinais que os parasitoides mais utilizam para perceber as mudanças ambientais e ajustar adequadamente o seu ciclo de vida (Koštál, 2011; Saunders, 2014). Dias com mais horas de luz são conhecidos por diminuir a longevidade e a fecundidade de alguns parasitoides (Koštál, 2011). O efeito de diferentes condições de fotoperíodo durante a fase pré-imaginal e adulta de H. hebetor foram investigados em laboratório com o objetivo de avaliar a paralisação, o parasitismo e o sucesso reprodutivo deste parasitoide em larvas de E. kuehniella
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.