Demography and Fitness of Anastatus japonicus Reared from Antheraea pernyi as a Biological Control Agent of Caligula japonica

Abstract

Japanese giant silkworm (JGS), Caligula japonica Moore, is an emerging defoliator pest of forest and fruit trees in East Asia, causing severe economic losses. To develop a cost-effective biological control program against JGS, we used eggs of the Chinese oak silkworm (COS) Antheraea pernyi Guérin-Méneville as an alternative host to rear the most dominant JGS egg parasitoid Anastatus japonicus Ashmead. We compared the demographic parameters and total parasitism (killing) rates of A. japonicus parasitizing JGS and COS eggs using an age-stage, two-sex life table method. The results showed that A. japonicus performed differently on these two different hosts. Anastatus japonicus reared from COS eggs had a higher fecundity (369.7 eggs per female) and a longer oviposition period (35.9 days) on the COS than JGS eggs (180.9 eggs; 24.0 days). Consequently, A. japonicus parasitizing COS eggs had a higher intrinsic rate of increase (r = 0.1466 d−1), finite rate of increase (λ = 1.1579 d−1) and net reproductive rate (R0 = 284.9 offspring) than those parasitizing JGS eggs (r = 0.1419 d−1, λ = 1.1525 d−1, R0 = 150.0 offspring). The total net parasitism rate (the number of parasitized hosts in which the parasitoids successfully developed) of A. japonicus parasitizing COS eggs was 284.9, significantly higher than that of A. japonicus parasitizing JGS eggs (150.0), while the net non-effective parasitism rate (the number of parasitized hosts in which the parasitoids failed to develop) of the former (0.0) was significantly lower than that of the latter (9.6). These results suggest that A. japonicus can be efficiently reared on the alternative (or factitious) COS eggs, and the reared parasitoids have a high biological control potential against the target JGS.

Selection and validation of reference genes for RT-qPCR-based analyses of Anastatus japonicus Ashmead (Hymenoptera: Helicopteridae)

“…Anastatus japonicus Ashmead (Hymenoptera: Helicopteridae) is an important egg parasitoid wasp that preys on a range of fruit bugs and forest caterpillars including Halyomorpha halys Stal, Tessaratoma papillosa Drury, and Riptortus pedestris Fabricius ( Zhao et al, 2019a ; Chen et al, 2019 ; Mi et al, 2020 ; Chen et al, 2021 ; Zhao et al, 2021 ; Wei et al, 2022 ). In commercial settings, A. japonicus is used as a form of biological control agent that is reared within Antheraea pernyi Guerin-Meneville eggs (Lepidoptera: Saturniidae) ( Zhao et al, 2021 ).…”

Identification and Comparative Expression Profiles of Candidate Olfactory Receptors in the Transcriptomes of the Important Egg Parasitoid Wasp Anastatus japonicus Ashmead (Hymenoptera: Eupelmidae)

“…Anastatus japonicus reared on Antheraea pernyi (Guérin-Méneville) (Lepidoptera: Saturniidae) eggs had a high biological control potential against Caligula japonica [ 7 , 8 ]. Therefore, A. japonicus has become an important biological control factor for fruit crop pests; more importantly, A. japonicus can be raised on A. pernyi eggs on a large scale indoors [ 8 , 9 ]. The ability of parasitoid wasps to search for hosts in complex chemical surroundings greatly affects their success in suppressing pest populations, thus affecting the economic value of fruit crops [ 10 ].…”

“…Studies concerning the ORs and IRs of parasitoid wasps are essential for understanding the mechanisms of the olfactory system that finds the host pests and for developing an olfactory-based integrated pest management (IPM) strategy. Previous research on A. japonicus focused primarily on its morphology, ecology, and raising [ 1 , 5 , 6 , 7 , 9 , 35 , 36 , 37 ]; little information is available on its chemosensory mechanisms. Two previous studies have reported transcriptome datasets from female A. japonicus antennae [ 38 , 39 ], but neither of these studies involved the female abdominal and male antennal transcriptomes.…”

Comparative demographics, population projections and egg maturation patterns of four eupelmid egg parasitoids on the factitious host Antherae pernyi

“…20,21 More importantly, we confirmed that these parasitoids reared on COS eggs were as effective as those reared on their natural hosts in parasitizing the target pest C. japonica. 3,22 However, our previous studies had evaluated the parasitism of these parasitoids on COS eggs for a short period of 24 h. The lifetime performance of these parasitoids and their population growth potential on COS eggs remain to be evaluated. 20 A life table is a powerful tool to compere the population demographics of different insects.…”

“…20 A life table is a powerful tool to compere the population demographics of different insects. 22,23 Information is also lacking on the reproductive traits (e.g., egg maturation patterns, oviposition dynamics, and offspring sex distribution) of these eupelmid egg parasitoids. A parasitoid's realized reproductive success would depend on mature egg load, adult female lifespan, hosts encountered, and oviposition behaviors.…”