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My research findings have implications for applied ecology and restoration policy in Ontario. I my discussions, and final chapter, I offer suggestions for the practitioner. / Restoration practitioners are tasked with recreating ecosystems using appropriate plant material that will provide ecological goods and services. However, best-practices for this type of intervention are not well developed for the southern Ontario landscape. Therefore, we evaluated approaches from four different aspects of seed-based restoration. First, we quantified the impact of seeding rate and application method on the success of grassland recreation. We also measured the impact of this restoration on the local bee community. Next, we compared a suite of native and nearly native wetland plants for their potential to prevent the establishment of invasive Phragmites australis. We measured the effect of competition on Phragmites across soil moisture and salinity gradients. Finally, we sought evidence for local specialization in a grassland forb, Monarda fistulosa, that would warrant policies to prevent the transfer of grassland seed for revegetation. In re-creating grasslands from seed, we found an interaction between seeding rate and application method. At a high rate, both methods had the same outcome, but at a low rate, a two-phase application method produced better results than a single-phase method. However, we also found that a single-phase method produced target plant cover with a higher floristic quality index after three years. In one study region, restored sites supported a greater bee abundance than un-restored sites, but bee abundance did not change after restoration in all regions. Of all the native species tested, Phragmites was supressed most by Bidens frondosa, a fast growing annual. We also found evidence that Phragmites may be less competitive at low soil moisture, and more competitive at high soil salinity. Finally, we found no evidence of local adaptation in M. fistulosa at the watershed scale; instead, we see independent effects of site and seed origin. This implies that current site conditions may not be favorable to the offspring of relic populations, and that local genotypes may not always be the best choice for restoration. / Dissertation / Doctor of Philosophy (PhD) / I tested four approaches to seed-based restoration. First I found that a two-phase hydroseeding method can be more efficient at a low seeding rate. Second, I found that the response of the bee community to local restoration may depend on broader landscape factors. Next, I found that Monarda fistulosa is not locally adapted at a watershed scale. Finally, I found that native annuals may be best at resisting invasion from Phragmites, and that some native species actually can facilitate invasion.

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Yes / This study used sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and a jar test apparatus to investigate the molecular weight (MW) and turbidity removal potential of Hibiscus seeds. Three Hibiscus species were assessed: okra crude extract (OCE), sabdariffa crude extract (SCE), and kenaf crude extract (KCE). Furthermore, purified versions of each [i.e., purified okra protein (POP), purified sabdariffa protein (PSP), and purified kenaf protein (PKP)] obtained from anionic exchange were evaluated. The results show that whereas the crude extracts had multiple proteins with MW sizes between 11 and 82 kDa, the purified samples consisted of a single coagulant protein band around 39 kDa. In each case, significant turbidity removal was recorded with the purified proteins; POP, PSP and PKP achieved approximately 98%, 94%, and 90% removal, respectively, at a reduced dosage of ≤0.6  mg/L. However, OCE and SCE achieved lower turbidity removal of 86% and 85% using 40-mg/L doses, respectively, whereas KCE recorded only 73% turbidity removal with a 60-mg/L dose. Sludge generation by crude and purified proteins was approximately 25% of sludge produced by aluminum sulfate and had the additional benefit of being biodegradable. Therefore, the coagulant protein in Hibiscus plant seeds has potential applications for improvements to accessing clean water in developing countries.

Chitinase has been suggested to play a role in defense mechanisms. In this study, the activity and expression of chitinase in muskmelon seeds were investigated. Multiple chitinase isoforms were detected in muskmelon seeds from early development through radicle emergence. One acidic and three basic chitinase isoforms were detected in developing seeds at 40 days after anthesis (DAA). Both acidic and basic chitinase isoforms were detected in endosperm tissue during seed imbibition and after radicle emergence. Basic chitinase isoforms, but not acidic isoforms, were detected in embryo tissue. Basic chitinase isoforms were also detected in the embryonic axis or radicle tissue. Taken together, these observations indicate that chitinases are regulated developmentally and in a tissue-specific manner in muskmelon seeds. Therefore the potential function of chitinases in muskmelon seeds is discussed. Two complete cDNAs, Cmchi1 and Cmchi2, and a partial genomic clone of Cmchi2 have been isolated from muskmelon seeds. Cmchi2 gene has two introns in the coding region while Cmchi1 is intronless. Cmchi1 cDNA encodes a class III chitinase while Cmchi2 cDNA encodes a class II chitinase. Cmchi1 and Cmchi2 proteins might be targeted to secretory pathways because they possess signal peptides. Southern blotting suggested that there is at least one additional gene similar to Cmchi1 in the muskmelon seed genome, while there is only one copy of Cmchi2. Northern blotting analysis showed that both Cmchi1 and Cmchi2 are expressed in the radicle tissue at the time of radicle emergence. This indicates that the expression is regulated developmentally and in a tissue-specific manner. Salicylic acid (SA) and benzothiadiazole (BTH) stimulated the expression of Cmchi1 but not Cmchi2 in seeds after radicle emergence, indicating that SA might be involved in inducing the expression of Cmchi1, while a different signal might be involved in triggering the expression of Cmchi2. The protein encoded by Cmchi1cDNA was expressed in E.coli. It did not show any enzymatic activity. Western blotting using an antibody raised against the class III chitinase protein in cucumber was inconclusive, as this antibody recognized the purified Cmchi1 fusion protein and other unknown proteins isolated from the embryonic axis or the radicle tissue. / Ph. D.