The main objectives of this thesis were to: determine the roles of the minor components, 89/11 (E/Z⁰) 1 1-tetradecenyl acetate (AC) and 85/15 (E/Z) 11-tetradecenol (OH), of the sex pheromone of the western spruce budworm, Choristoneura occidentalis Freeman, in the orientation and pre-copulatory behaviors of the male moth; and, to evaluate various combinations of pheromone concentration, trap design, and maintenance regime for monitoring the budworm. The behavior of the male moths was observed, in a wind tunnel and in the field, in response to virgin females and to synthetic sex pheromone components, alone and in blends. The pheromones were incorporated into polyvinyl chloride rods at concentrations from 0.00005-0.5% (w:w) and release rates were estimated by gas-liquid chromatography of volatiles captured on Porapak-Q. OH contamination in lures of the major component, 92/8 (E/Z)-11-tetradecenal (ALD), and the AC, made it impossible to determine precisely the effects of either AC, ALD, or ALD+AC on the behavior of the male moth, but still allowed the testing of blends of ALD+AC+OH which resembled those released by virgin females. The moths were from three sources: a long-established non-diapausing laboratory colony; wild budworms collected near Ashcroft, B.C.; and crosses between laboratory males and wild females (lab-wild). The threshold concentration of ALD necessary to stimulate upwind flight was between 0.0005 and 0.005%; response peaked at 0.05% and dropped off above this concentration. The net upwind ground speed of flight decreased significantly at higher concentrations of ALD in the laboratory moths, and as the moths approached the lure with all three populations. In most experiments, the virgin female stimulated a greater percentage of males to contact the lure, and a faster upwind net ground speed of flight, than did ALD at about the same release rate. AC and OH stimulated response on an electroantennogram, but by themselves were not attractive to males in the wind tunnel. The addition of OH to 0.05% ALD significantly decreased the percentages of males locking-on (0.5% OH) and flying upwind (0.005% OH) in wild and lab-wild moths respectively, and significantly increased the percentage copulatory attempts of lab-wild males (0.005% OH). In the lab-wild males, a blend of ALD+AC+OH approximating that from a virgin female significantly increased the percentages of upwind flights, lure contacts, and copulatory attempts over those to ALD alone. The total blend, and not just the major component, affected long range behavior of the male moth. The laboratory males appeared less sensitive to the addition of minor components to 0.05% ALD than did the wild or lab-wild males. The mean total season's catch/plot in five non-maintained Uni-traps, baited with 0.05% ALD, was significantly correlated with the number of larvae/m² foliage in the same generation (r = 0.97), but only when a lower valley plot with very low larval density was excluded (plot 12). Correlations were significant (P ≤ 0.10) between larval density/plot in 1985 and the total moth catch/plot (n = 1 trap/plot) in 1984 in sticky traps (r = 0.45) and Uni-traps (r = 0.44) baited with 0.05% ALD and maintained. The latter correlation was significantly improved (r = 0.67; ≤ 0.05) when plot 12 was excluded. The addition of plot basal area/ha or foliage biomass/ha as independent variables significantly improved the coefficient of determination for the regression of larval density/plot in 1985 vs total seasons catch/plot in 1984, but again only when plot 12 was excluded. Of the trap systems evaluated, the Uni-trap, baited with 0.05% ALD, showed the most promise for monitoring the western spruce budworm, but permanent sample plots will have to be established and followed for several years to determine whether the system can be operational. / Forestry, Faculty of / Graduate

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The mineral nutrient storage reserves in various parts of white spruce (Picea glauca) seeds and somatic embryos were investigated. Somatic embryos are produced in tissue culture from single cells or small groups of cells. These cells are induced to produce a callus, which is then stimulated to produce mature somatic embryos that are desiccated down to moisture content levels comparable to those of a mature dry seed. Morphological comparisons revealed that somatic and zygotic embryos are very similar. Somatic embryos of white spruce; however, were larger, had a flared arrangement of cotyledons, had more prominent suspensor regions, had intercellular spaces in the ground meristem tissue and had ground meristem cells that had divided in several planes of division. Using a wet ashing protocol, anion exchange resins and the molybdenum blue colourimetric reaction, the total levels of P and the amount of P bound to phytic acid were measured. Phytic acid (or phytate) is the major nutrient storage compound in seeds. Although differences were found on a dry weight basis, a single somatic and a single zygotic embryo had similar levels of P. Somatic embryos produced in different batches varied in their levels of phytic acid, but a somatic embryo could have similar levels of phytic acid as a zygotic embryo. The large female gametophyte contained 86% of the total P and 95% of the total phytic acid in a single seed. Electron microscopy and energy dispersive x-ray analysis found phytate-rich globoids in the procambium and ground meristem tissues of both types of embryos. Globoids contained high P, moderate K and Mg, and little if any Ca, Fe and Zn. Globoids were generally larger and more frequent in zygotic embryos. Globoids from the cotyledon procambium of zygotic embryos also contained moderate levels of Fe. Iron-rich particles (possible Fe-phytate deposits) were found in the protoderm, procambium and ground meristem of both types of embryos. These deposits contained high P and Fe, moderate K and Mg, and little if any Ca and Zn. Globoid and Fe-rich particle compositions were similar in both embryo types, but significantly higher Fe:P ratios were found in zygotic embryos. Atomic absorption spectroscopy was used to measure total K, Mg, Ca, Fe and Zn levels. Although differences were found on a dry weight basis, a single white spruce somatic or zygotic embryo contained similar levels of all these elements. The female gametophyte contained high levels of these elements and the seed coat contained considerable Ca. Potassium leakage during imbibition in germination medium revealed that a single somatic and zygotic embryo of white spruce leaked similar levels of K. Pretreatment of somatic embryos in a high relative humidity environment resulted in decreased potassium leakage by 80 and 120 min. of imbibition. The seed coat was found to reduce the amounts of K leaked. Surface cells in dry somatic and zygotic embryos were found to be wrinkled, but cells in zygotic embryos were more shrunken in appearance. During imbibition, cells became more turgid; but after 120 min. of imbibition, surface cells still showed signs of wrinkling. To date, this is the first major report of mineral nutrition in white spruce seeds and is the first comprehensive comparison of mineral nutrients in white spruce seeds and somatic embryos. These results may be useful in producing complete artificial white spruce seeds. / Thesis / Master of Science (MS)

An ecophysiological comparison among species was conducted to investigate the possible factors controlling the distribution of North American spruce (Picea) species, especially with regard to the possible influence of global change. The seedlings of 8 North American spruce species were grown in a growth chamber, with half of them being given an episodic 'increased temperature and drought' stress treatment. Trait values among species, particularly growth analysis components, were compared and related to climatic variables associated with the geographical range of the species. Relative growth rate (RGR) and specific leaf area (SLA) were positively correlated with latitude, and the leaf weight ratio (LWR) variation negatively with the dryness of species' natural ranges. All these relationships hold with both messed and unstressed seedlings, even thou seedling response to the stress was significant. The SLA-latitude and LWR-dryness relationships are likely to have ecological significance, and this indicates that foliage stricture (SLA) and allocation (LWR) play important roles determining a species range along temperature and dryness gradients.

Thesis (M.S.)--Oregon State University, 1998. / Typescript (photocopy). Includes bibliographical references (leaves 53-56). Also available via the World Wide Web.

Thesis (M.A.)--West Virginia University, 1999. / Title from document title page. Document formatted into pages; contains xi, 80 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references (p. 72-77).

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2004. / Appendix reprints four papers and manuscripts co-authored with others. Includes bibliographical references. Also partially issued electronically via World Wide Web in PDF format; online version lacks appendix.