Importance of host feeding for parasitoids that attack honeydew-producing hosts

• Published in: Entomologia experimentalis et applicata Vol. 117; no. 2; pp. 147 - 154
• Main Authors: Burger, J.M.S, Kormany, A, Lenteren, J.C. van, Vet, L.E.M
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01.11.2005; Blackwell
• Subjects: Aleyrodidae; Animal and plant ecology; Animal, plant and microbial ecology; Animals; Aphelinidae; aphytis-melinus; Autoecology; bemisia-tabaci; Biological and medical sciences; Biological control; Braconidae; Control; egg load; egg-production; Encarsia formosa; fecundity; feeding behavior; Fundamental and applied biological sciences. Psychology; Homoptera; honeydew; host-feeding behavior; host-parasite relationships; Hymenoptera; insect parasitoids; life history trade-offs; life-history trade-off; lifetime reproductive success; mortality; nutrient acquisition; nutrient allocation; nutrient availability; nutritive value; oviposition; parasitoids; Phytopathology. Animal pests. Plant and forest protection; Protozoa. Invertebrata; Protozoa. Invertebrates; strategies; Trialeurodes vaporariorum; wasp; Insecta; Biological control; host-feeding behavior; nutrient allocation; life-history trade-off; Pest; Entomophagous; Homoptera; Beneficial animal; Chalcidoidea; nutrient acquisition; Feeding behavior; Trialeurodes vaporariorum; Aphelinidae; Hemolymph; Host; Parasitoid; Encarsia formosa; Arthropoda; Nutrient; Aleyrodidae; Hymenoptera; Invertebrata; Fecundity; Honeydew
• ISSN: 0013-8703; 1570-7458
• DOI: 10.1111/j.1570-7458.2005.00341.x

Insect parasitoids lay their eggs in arthropods. Some parasitoid species not only use their arthropod host for oviposition but also for feeding. Host feeding provides nutrients to the adult female parasitoid. However, in many species, host feeding destroys an opportunity to oviposit. For parasitoids that attack Homoptera, honeydew is a nutrient-rich alternative that can be directly imbibed from the host anus without injuring the host. A recent study showed that feeding on host-derived honeydew can be an advantageous alternative in terms of egg quantity and longevity. Here we explore the conditions under which destructive host feeding can provide an advantage over feeding on honeydew. For 5 days, Encarsia formosa Gahan (Hymenoptera: Aphelinidae) parasitoids were allowed daily up to 3 h to oviposit until host feeding was attempted. Host feedings were either prevented or allowed and parasitoids had ad libitum access to honeydew between foraging bouts. Even in the presence of honeydew, parasitoids allowed to host feed laid more eggs per hour of foraging per host-feeding attempt than parasitoids that were prevented from host feeding. The higher egg-laying rate was not compromised by survival or by change in egg volume over time. In conclusion, host feeding can provide an advantage over feeding on honeydew. This applies most likely under conditions of high host density or low extrinsic mortality of adult parasitoids, when alternative food sources cannot supply enough nutrients to prevent egg limitation. We discuss how to integrate ecological and physiological studies on host-feeding behavior.