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| Author(s): |
Fernando Luis Consoli
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Piracicaba. |
| Institution: | Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC) |
| Defense date: | 1994-02-03 |
| Advisor: | José Roberto Postali Parra |
| Abstract | |
The objective of this study was to develop an artificial diet for "in vitro" rearing of Trichogramma galloi Zucchi 1988 and T. pretiosum Riley, 1879. For developing such diets, the ideal proportions of each of their components and the nutrional quality of the hemolymph and of the holotissues of different insect species were determined as one of the main components of the artificial diets. The results obtained indicated variations in the nutritional requirements of the two parasitoid species under study which originated diets with different proportions. The hemolymph of Helicoverpa zea (Boddie, 1850) proved to be the most adequate for "in vitro" rearing of those parasitoids. It was possible to rear both insects up to the adult stage on an artificial medium and this is the first report on "in vitro" rearing of T. galloi. The presence of egg yolk and of hemolymph concentrations over 40% were essential for full development of T. galloi and T. pretiosum. The inclusion of Heliothis virescens (Fabr., 1781) egg juice in the T. pretiosum diet increased the larval and pupal viability as well as the number of normal pupae and adults formed. Volumes of artificial diet between 3µl and 4µl proved to be adequate for the development and growth of T. galloi reared on artificial diets using excaveted slides as a container. Insects reared "in vitro" showed lower longevity and parasitism capacity as compared with those reared on natural and alternative host eggs. Wing and abdominal malformations occurred in T. galloi and T. pretiosum reared on artificial diets, although they presented normal reproductive organs and a similar size to that of insects reared "in vivo". The host preference of T. galloi reared on artificial diet was similar to that of the insect reared on natural host eggs. The analyses of proteins and free aminoacids of the various insect components (eggs, hemolymph and pupal holotissues) used in preparing the artificial diets indicated the differences in protein fractions and in the amount of free aminoacids for each of these components, respectively. Such differences were due to the differences in biological values of both parasitoids when reared on different artificial diets. (AU) | |