This work covers stages one through seven (of nine stages) of a classical biological
control program for Mediterranean fruit fly (=medfly), Ceratitis capitata (Wiedemann). Major
research objectives concentrate on stage five (exploration and collection of natural enemies),
and stage seven (testing and selecting natural enemies for additional work).
Coffee was collected monthly from three locations in Kenya from November 1997
through July 1999. Four species of tephritid flies and ten parasitoid species were recovered.
Four guilds of parasitoids were recorded, and two egg-prepupal endoparasitoids, Fopius
caudatus (Szépligeti) and F. ceratitivorus (Wharton), were discovered. The oviposition behavior
of these two species is contrasted. Domination of this tropical parasitoid assemblage by
koinobionts is discussed relative to the dominance of temperate fruit-infesting tephritid systems
by idiobionts.
Fruit handling procedures were examined for impact on overall percent emergence and
specifically percent emergence of flies versus parasitoids. It was determined that stirring
samples had a significant positive effect on overall emergence, however daily misting of fruit did
not. The only treatment without a significant bias in fly emergence over parasitoids was the
stirred/dry treatment. Effects of these results on rearing procedures are discussed.
Host specificity and host suitability of parasitoids reared from coffee were examined via:
(1) association of parasitoids with host flies based on characteristics of the fly puparia from which parasitoids emerged, (2) rearing of cucurbit infesting tephritids and their parasitoids in
Kenya, (3) rearing of flowerhead infesting tephritids and their parasitoids in Kenya and Hawaii,
and (4) host range testing of Psyttalia species in Kenya and Hawaii. These results are discussed
in terms of their utility for predicting nontarget effects.
Psyttalia concolor (Szépligeti) was shipped to Hawaii and tested against the nontarget
gall forming tephritid Procecidochares utilis Stone introduced to control the weed Ageretina
adenophora (Maui pamakani). Psyttalia concolor failed to attack the gall-forming P. utilis both
in choice and no-choice tests, but readily attacked tephritid larvae offered in fruit in choice tests.
Recommendations for further testing and release of the parasitoids from Kenya are
discussed for Hawaii and Latin America.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/3877 |
| Date | 16 August 2006 |
| Creators | Trostle Duke, Marcia Katherine |
| Contributors | Wharton, Robert A. |
| Publisher | Texas A&M University |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation, text |
| Format | 2273125 bytes, electronic, application/pdf, born digital |
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