Host‐habitat conditioning in the eulophid egg parasitoid, Edovum puttleri: effects of herbivore's host and its food plant

Abstract

The egg parasitoid, Edovum puttleri Grissell, was cultured from eggs of two Leptinotarsa hosts, L. decemlineata (Say) and L. texana Schaeffer, and experienced on eggs from three L. decemlineata food plants, namely potato, Solanum tuberosum tuberosum L., eggplant, S. melongena L., and tomato, Lycopersicon esculentum Mill. Host preference of the various cultures was determined using choice tests. Parasitoid choices were influenced by the Leptinotarsa rearing host. Wasps, reared from L. decemlineata eggs from a mixture of all three food plants and experienced on egg masses from all three food plants, preferred to parasitize egg masses from potato. Wasps, reared from L. texana eggs from silver leaf nightshade, S. elaeagnifolium L., and experienced on egg masses from all three food plants, preferred to parasitize egg masses from tomato. Choices were also influenced by the herbivores food plant that wasps were conditioned to. Wasps, reared from L. texana and experienced on egg masses from potato, preferred to parasitize egg masses from potato. Wasps, reared from L. decemlineata on potato and experienced on egg masses from potato, preferred to parasitize egg masses from potato. Wasps, reared from L. decemlineata on tomato and experienced on egg masses from tomato, did not display a distinct host preference. Within-egg mass parasitism (i.e., number of eggs per mass that were parasitized, probed, etc.) did not consistently differ among the three food plants. The implications of these data in parasitoid ecology and biological control programs for L. decemlineata are discussed.

Voracity and feeding preferences of two aphidophagous coccinellids on Aphis citricola and Tetranychus urticae

“…Among insects, several studies have shown that a previous feeding experience could modify subsequent feeding behaviour. Food selection and preference could be influenced by a previous exposure to one food type in phytophagous species (de Boer & Hanson, 1984;Eijsackers & van Lanteren, 1970;Hanson, 1983;Papaj & Prokopy, 1989), and in parasitoids (Jansson & Lashomb, 1988;Mandevile & Mullens, 1990;Thorpe & Jones, 1937;van Alphen & Vet, 1986). Conditioning for prey preference by predator species, occurs rarely.…”

Edovum puttleri [Hym.: Eulophidae]: Biological activity and responses to normal and frozen eggs ofLeptinotarsa decemlineata [Col.: Chrysomelidae]

“…Again, both the frozen and normal eggs were replaced every 2 days until the death of each female. Only CPB eggs oviposited on paper were used so as to prevent the rotting of plant material which had occurred in the preceding experiment, although it appears that this wasp may orient towards potato plant produced synomones (Jansson & Lashomb, 1988).…”