Fecundity and success of progeny produced by Homalodisca coagulata (Hemiptera : Cicadellidae) on single host species
This study tested the hypothesis that Homalodisca coagulata (Say) (Hemiptera: Cicadellidae) confined to a single host cannot successfully produce progeny and survive to complete a generation. We found that H. coagulata can successfully oviposit and produce viable offspring when confined to a single host species: grape (Vitis vinifera L.) (Vitidaceae), citrus (Citrus sinensis (L.) Osbeck.) (Rutaceae) or oleander (Nerium oleandrum L.) (Apocynaceae). In 2002, more egg masses and adults were found on citrus than on grape or oleander. In 2004, there was no significant difference in the number of egg masses on the different hosts, but more adults were produced on grape than on citrus or oleander. Our results indicate that H. coagulata do not require multiple hosts or a compulsory movement of adults between hosts to produce a subsequent generation. Large populations of H. coagulata could therefore occur in monoculture situations and on hosts that may not be treated in eradication programs. Because citrus and oleanders are commonly found in close proximity both to one another and to grapes, it is important to consider their contributions as sources of H. coagulata when discussing Pierce's disease epidemiology.