Effects of parasitoid and host age on the parasitism of Trichogramma pretiosum on eggs of Anticarsia gemmatalis

Abstract

The ages of parasitoid females and their hosts can have substantial effects on parasitism and parasitoid efficacy. This relationship has been investigated over the last few decades and found to vary among species. To our knowledge, it was virtually unknown for Trichogramma pretiosum wasps that parasitize Anticarsia gemmatalis eggs. Therefore, the influence of parasitoid and host age on the parasitism of T. pretiosum on eggs of A. gemmatalis was here evaluated in three independent bioassays. Neither the number of parasitized eggs nor that of emerged parasitoids differed between T. pretiosum females of different age. The number of parasitoids per egg and the sex ratio were higher for 5-day-old females. Regarding host age, the number of parasitized eggs was highest for A. gemmatalis eggs aged 24 h (9.60), followed by eggs aged 48 h (1.00), while no parasitism was observed for eggs aged 72 h. The number of parasitoids per egg and sex ratio were not influenced by host age. Preference was significantly higher for host eggs aged 24 h (79.67%), followed by eggs aged 48 h (16.99%) and 72 h (3.33%). Accordingly to these results, the key challenge for a successful T. pretiosum release to control A. gemmatalis in the field is to synchronize the presence of up to 5-day-old adults with the most susceptible phase of the host eggs (1 day).

Variation among populations ofTrichogramma euproctidis(Hymenoptera: Trichogrammatidae) revealed by life table parameters: perspectives for biological control

“…For all 3 T. euproctidis populations, the highest emergence rate was obtained from 1-day-old eggs. This result differs from previous studies in other Trichogramma species-host species systems for which the host egg age does not significantly affect the emergence rate (Bueno et al 2012, Pizzol et al 2012, Stinguel et al 2013, Queiroz et al 2020, Atashi et al 2021). Thus, the quality of the host egg at different ages is an important factor affecting the acceptability and suitability of various hosts for several Trichogramma species (Tunçbilex and Ayvaz 2003).…”

Age- and Density-Dependent Parasitism Rate and Development Time of the Generalist Egg-Parasitoid Ooencyrtus telenomicida (Hymenoptera: Encyrtidae) on Eggs of the Brown Marmorated Stink Bug, Halyomorpha halys

“…Likewise, parasitoid age (1 to 5 days old) of Trichogramma pretiosum (Riley) (Hymenoptera: Trichogrammatidae) significantly affected its efficacy on Anticarsia gemmatalis (Huebner) (Lepidoptera: Erebidae) eggs. A higher number of parasitoids per egg emerged after parasitism by older T. pretiosum females (5 days old) [53].…”

Reproduction of Ooencyrtus submetallicus (Hymenoptera: Encyrtidae) and Trissolcus sp. aff. urichi (Hymenoptera: Scelionidae) in Eggs of Nezara viridula (Hemiptera: Pentatomidae) of Different Ages

“…Therefore, having knowledge and development of research involving the interaction between the parasitoid and the host is necessary to increase the efficiency and success of biological control programs (Parra & Zucchi, 2004;Parra et al, 2019). Among these interactions, studying the age of both parasitoid and host females is not only important for analyzing the performance of biological control agents but also for predicting their establishment in the field (Cingolani et al, 2014;Queiroz et al, 2019;Hill et al, 2019;Queiroz et al, 2020a). Considering this, we determined the age of the parasitoids O. submetallicus and Trissolcus sp.…”