Host age-mediated effects on fitness traits of five Anastatus parasitoids: Implications for optimizing biological control of Riptortus pedestris.

No single host is optimal: effects of fruit species on development and adult performance in Anastrepha fraterculus (Diptera: Tephritidae)

Many phytophagous insects develop within discrete and non-renewable resources, such as fruits, making host choice a critical determinant of offspring performance. In tephritid fruit flies, host fruit quality can strongly influence development, survival, and adult reproductive traits, yet no single host may optimize all life-history parameters. Here, we evaluated the effects of six host fruit species—native and exotic—on larval development and adult performance of the South American fruit fly Anastrepha fraterculus, a highly polyphagous and economically important pest. Under controlled laboratory conditions, we quantified developmental time, pupal survival, adult size, ovary development, male sexual maturation, and starvation resistance. Host species significantly affected all measured traits, revealing pronounced trade-offs among life-history parameters. Guava, a native host, supported the fastest larval development but produced smaller adults with reduced ovary development and lower starvation resistance. Feijoa, another native host, behaved similarly to guava, although pupal mortality was higher and sexual maturation faster than in guava. Peach and plum consistently yielded larger adults with well-developed ovaries and higher overall performance, whereas loquat generally resulted in poorer outcomes across several traits. Grapefruit induced prolonged larval development but promoted early male sexual maturation. Heatmap and PCA analyses confirmed that no single host maximized performance across all traits. These results challenge the assumption that native hosts necessarily confer superior fitness and suggest a decoupling between host use in nature and host suitability under laboratory conditions. Our findings highlight the complexity of host–insect interactions in polyphagous fruit flies and suggest that different host species may be selectively advantageous depending on ecological context and demographic needs. Understanding these trade-offs is essential for predicting population dynamics and improving integrated management strategies for A. fraterculus.

Stage-specific predation and functional response of Orius insidiosus (Hemiptera: Anthocoridae) toward Diaphorina citri (Hemiptera: Psyllidae) and differential toxicity of formulated pesticide mixtures.

Egg mass scale thickness: Multifunctional maternal defenses driving niche expansion and global pest status of Spodoptera spp

Background : The genus Spodoptera (Lepidoptera: Noctuidae) includes some of the most destructive agricultural pests globally, such as S. frugiperda , S. litura , and S. exigua . Following oviposition, female moths cover their egg masses with abdominal scales, forming a protective layer whose thickness varies among species and individuals. This trait may enhance egg survival and contribute to pest outbreaks, yet its morphological characteristics and ecological significance have not been systematically reviewed. Methods : This review synthesizes the available literature to integrate current knowledge on the morphological characteristics and ecological functions of egg mass scale-layer thickness in Spodoptera , with particular emphasis on its implications for integrated pest management (IPM). Results : The scale layer functions as a multifunctional barrier that protects eggs from natural enemies, mitigates abiotic stresses, and may reduce susceptibility to microbial pathogens and chemical insecticides. This defensive trait appears to favor specialist egg parasitoids such as Telenomus remus over generalist Trichogramma species, while simultaneously reducing the efficacy of contact ovicides. Conclusion : Egg mass scale-layer thickness represents a key behavioral adaptation that enhances egg survival and reduces egg-stage mortality, thereby contributing to the ecological success, invasion potential, and global pest status of Spodoptera species. A deeper understanding of this trait may provide a valuable foundation for improving biological and chemical control strategies targeting these pests.

Host oviposition strategy shapes the parasitism performance and functional response of Telenomus remus.

BACKGROUND Telenomus remus (Nixon) is a promising egg parasitoid for controlling Spodoptera litura, Agrotis ipsilon, and Helicoverpa armigera. Although this species has been successfully reared under laboratory conditions, we assess how contrasting oviposition behaviors of sympatric noctuid pests influence T. remus performance. RESULTS We found that T. remus showed a marked preference for the large, cohesive egg masses of S. litura, achieving significantly higher parasitism rates, emergence rates, and female progeny proportions, as well as faster immature development, compared with the small clusters of A. ipsilon and the scattered eggs of H. armigera. Functional-response analyses confirmed its highest attack rate (a = 0.082 h-1) and shortest handling time (Th = 0.55 h) on S. litura. Host egg age reduced performance, but extended exposure improved outcomes. CONCLUSION These findings reveal that host oviposition behavior is a key determinant of T. remus efficacy and may help inform release timing, duration, and target pest selection, pending field validation. Data are discussed in relation to developing robust, resilient integrated pest management programs to control pests in integrated agriculture. © 2026 Society of Chemical Industry.

Life‐History Traits and Overwintering of Actia interrupta (Diptera: Tachinidae), a Larval Parasitoid of Choristoneura fumiferana (Lepidoptera: Tortricidae)

Actia interrupta (Diptera: Tachinidae) is an important larval parasitoid of the eastern spruce budworm, Choristoneura fumiferana (Lepidoptera: Tortricidae), especially during low‐density (endemic) population phases. Despite its ecological importance, information on its basic biology remains limited. In a laboratory study, we described the morphology and development of immature stages, measured the duration of development at different temperatures, adult longevity, and the temporal dynamics of egg and larval maturation in females. Females were confirmed to be larviparous, larvipositing first‐instar larvae following a post‐copulation gestation period. The parasitoid develops through three larval instars, with the final instar forming a secondary respiratory funnel within the host prior to egression. Development time decreased with increasing temperature, while adult longevity was not affected by sex or mating status. Behavioral assays showed that females preferentially flied, landed, and larviposited on substrates containing hosts, supporting an indirect larviposition strategy. Finally, we demonstrate for the first time that the oblique‐banded leafroller, Choristoneura rosaceana (Lepidoptera: Tortricidae), serves as a suitable overwintering host for A. interrupta . These results provide key biological insights into a parasitoid species contributing to the regulation of low‐density spruce budworm populations.

How Do Host–Parasitoid Interactions Shape the Effectiveness of Anagyrus aberiae as a Biological Control Agent?

Simple Summary Delottococcus aberiae is an invasive mealybug that has become an important pest of citrus crops in eastern Spain, causing damage that reduces fruit quality and economic value. To help control this pest, a parasitic wasp, Anagyrus aberiae, was introduced from the mealybug’s area of origin in South Africa in 2019. However, little was known about how this natural enemy attacks the pest and how effective it may be under different conditions. In this study, we examined which life stages of the mealybug are most suitable for the parasitoid, how parasitism affects mealybug reproduction, and the ability of the parasitoid population to grow and respond to different pest densities. The parasitoid was able to attack all tested stages of D. aberiae but strongly preferred adult females. Parasitized female mealybugs produced fewer eggs than unparasitized control ones, and females already laying eggs stopped doing so within two days after parasitism. The parasitoid also showed a strong capacity for population growth and parasitized more mealybugs as host density increased, although this response slowed at high densities. These findings provide valuable information for improving biological control strategies against D. aberiae and for guiding future research on this host–parasitoid system.