For many years the study of insect pathogens was not regarded as one of the duties of the entomologist. When insects became numerous and caused economic damage, they were combatted either with insecticides or by the introduction of parasitic or predaceous insects. The use of insecticides in the forest is not economical. Forest entomologists therefore resorted largely to the introduction and propagation of parasitic insects. Unfortunately, experience has shown, in many cases, that introduced parasites multiply too slowly to check current insect infestations. Insect pathogens multiply rapidly and at times contribute more to the control of insect pests than all other combined control factors. The control of the European spruce sawfly by disease created new interest in the possible use of insect pathogens in biological control. Relatively few insect diseases have been discovered. Those which are now known are the obvious cases. A study of any insect population probably would reveal one or more pathogens affecting it. This is being demonstrated as the result of the newly created interest and research in insect pathology. The discovery of an organism pathogenic to insects does not necessarily imply that it can be propagated and immediately disseminated in nature and effect control. This has been attempted too often in the past with disappointing results. Any program of artificial dissemination must be based on a thorough knowledge of the nature of the organism [...]
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.123788 |
| Date | January 1949 |
| Creators | Bird, F. T. |
| Contributors | DuPorte, E. (Supervisor) |
| 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 Entomology.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000597747, Theses scanned by McGill Library. |
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