From 1991 to 1994 inclusively, a field and laboratory study was undertaken on egg parasitoids of the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) to determine their potential in controlling their host. Five species were found to parasitize Lygus eggs in southwestern Quebec. They were three mymarids: Anaphes iole Girault, Polynema pratensiphagum (Walley), and Erythmelus miridiphagus Dozier (Mymaridae) and two scelionids: Telenomus nysivorus Huggert and Telenomus n.sp. (a new species near strelzovi Vasiliev) (Scelionidae). The maximum levels of field parasitism by these parasitoids were 20, 70, 35, and 70% (for both species of Telenomus), respectively. The field parasitism was determined on Lygus eggs inserted in Contender green beans, Phaseolus vulgaris L., Irish cobbler potatoes, Solanum tuberosum L., and alfalfa, Medicago sativa L. P. pratensiphagum and Telenomus were the most abundant parasitoid species recorded. / In 1991 and 1992 the seasonal occurrences of these parasitoids were investigated in three different habitats: mixed weeds, alfalfa, and crown vetch, Coronilla varia L. In both years Telenomus n.sp. was the most numerous parasitoid in all three habitats throughout the season, and had a strong synchrony with L. lineolaris populations. / The laboratory and field monitoring experiments on the overwintering of A. iole, P. pratensiphagum and E. miridiphagus indicated that the presence of an alternative host is essential for the overwintering of these parasitoids. The eggs of the alfalfa plant bug, Adelphocoris lineolatus (Geoze) were the most common overwintering host for all three mymarids and Canada fleabane, Erigeron canadensis L. sustained more Adelphocoris eggs and egg parasitoids than other weed hosts. / In the laboratory the parasitoid survival, mortality, fecundity, and adult longevity were determined for P. pratensiphagum, A. iole and Telenomus n.sp. The females of all three species lived longer than males, but males emerged 24 hours before females, and all are solitary parasitoids. Telenomus n.sp. showed a higher rate of survival (93%) and a higher rate of parasitism (87%) than other species under laboratory conditions. / For rearing L. lineolaris, potato sprouts, S. tuberosum were found to be the medium preferable to potato slices and Patana artificial diets. This medium is worthy of further investigation for use in augmenting the egg parasitoids of L. lineolaris.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.37690 |
Date | January 1995 |
Creators | Al-Ghamdi, Khalid M. |
Contributors | Stewart, Robin K. (advisor) |
Publisher | McGill University |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Format | application/pdf |
Coverage | Doctor of Philosophy (Department of Natural Resource Sciences.) |
Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
Relation | alephsysno: 001809197, proquestno: NQ70175, Theses scanned by UMI/ProQuest. |
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