Horizontal distribution of Diabrotica longicornis (Say) eggs around plants was random in three Quebec cornfields. Vertically, 72% and 24% eggs occurred in the surface 10 cm soil before and after fall plowing, respectively. A 5 x 10 cm x 15 cm (deep) sampling unit was appropriate for estimating egg populations before plowing. Thereafter, 20 cm depth was needed. Larvae and pupae were concentrated around the root system and a soil quadrat 20 x 20 cm x 10 cm (deep) was an easily reproducible sampling unit. Direct counting on corn plants in early morning was the most efficient method for adult sampling. Sample sizes for all stages were calculated for different precision levels. Spatial distribution of eggs and larval field populations were contagious, and a stratified random sampling is appropriate for density estimation. Spatial distribution of adults changed with corn phenology. Average mortality of overwintering eggs was 66% and of spring larvae 89%. The field population density of beetles did not change significantly during 1979-82.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.71849 |
| Date | January 1983 |
| Creators | Matin, Muhammad Abdul. |
| 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: 000155637, proquestno: AAINK64597, Theses scanned by UMI/ProQuest. |
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