Browsing by Author "Mills, N"

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    Aspects of the biology of Hyssopus pallidus (Hymenoptera : Eulophidae), a parasitoid of the codling moth (Lepidoptera : Olethreutidae)
    (ENTOMOL SOC AMER, 1999) Zaviezo, T; Mills, N
    Hyssopus pallidus (Askew) is a gregarious ectoparasitoid that attacks 2nd-instar to prepupal codling moth. Host attack includes initial probing, host paralysis, oviposition from 2 to 30 ears per host, nondestructive host feeding, and brood guarding. The development rate of the immature stages increased with temperature, with a life cycle minimum threshold of 10 degrees C and a maximum threshold between 30-35 degrees C. Female development time from oviposition to adult emergence decreased from 39 d at 15 degrees C to 12 d at 30 degrees C. Female longevity decreased from 115 d at 15 degrees C to 40 d at 30 degrees C, and was significantly increased by provision of honey, but not by host feeding. Lifetime fecundity was estimated to be lm eggs, with a female-biased progeny sex ratio of 0.58 males and 13.02 females per host. The presence of a Ist female guarding her brood did not prevent or influence the level of superparasitism by a 2nd female; experienced females were less likely to superparasitize than naive females, and superparasitism was most frequent among bloods 24 h old. The host specificity of H. pallidus was tested using no-choice tests with 5 common orchard Microlepidoptera. It successfully attacked and developed on 100% of codling moth larvae and 60% of orange tortrix larvae. It paralyzed but did not oviposit on 20% of Pandemis pyrusana Kearfott larvae. and it did not attack obliquebanded leafroller or navel orangeworm.
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    Factors influencing the evolution of clutch size in a gregarious insect parasitoid
    (WILEY-BLACKWELL, 2000) Zaviezo, T; Mills, N
    1. In this study we examined the clutch size of Hyssopus pallidus (Askew) (Hymenoptera, Eulophidae), a gregarious ectoparasitoid of codling moth (Lepidoptera, Tortricidae) larvae that is characterized by a host handling time of 2 days approximately.