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Sand-Based Turfgrass Root-Zone Modification With Biochar, Shane R. Brockhoff Jan 2010

Sand-Based Turfgrass Root-Zone Modification With Biochar, Shane R. Brockhoff

Graduate Theses and Dissertations

Sand-based turfgrass root-zones are limited in nutrient retention and water holding capacity. Peat moss is often used to offset these deficiencies, but peat moss is prone to decomposition. Biochar, a co-product of the fast pyrolysis process used to produce bio-oil, may have similar benefits as peat moss while being less prone to decomposition. In addition, because biochar is relatively stable over time, sand-based turfgrass ecosystems established with biochar may become a viable long term carbon sequestration vehicle. At field capacity, sand-based media containing 25% biochar retained 63 and 73% more water compared to media containing 5% biochar and a pure ...


Epidemiological Studies On The Infection Process And Symptom Expression Of Soybean Sudden Death Syndrome, Carlos Cecilio Gongora-Canul Jan 2010

Epidemiological Studies On The Infection Process And Symptom Expression Of Soybean Sudden Death Syndrome, Carlos Cecilio Gongora-Canul

Graduate Theses and Dissertations

Sudden death syndrome (SDS) caused by Fusarium virguliforme (Aoki, O'Donnel, Homma & Lattanzi) is one of the most important soybean (Glycine max (L.) Merr.) diseases in the US. Management strategies currently available for this disease are not always effective, partly due to the high variability in symptom expression that occurs in field environments. To clarify the relationship between progress of root rot and foliar symptoms, soybean seedlings were inoculated at five inoculum densities and were destructively sampled over a 50 day period. Disease severity and area under disease progress curve (AUDPC) increased in response to increasing inoculum density (P < 0.01), particularly for foliar symptoms. Root rot severity evaluated 15 to 31 days after inoculation (DAI) was most highly correlated (r ...


Interactions Between Lesion Nematodes And Corn Pathogens, Marcos Paulo Da Silva Jan 2010

Interactions Between Lesion Nematodes And Corn Pathogens, Marcos Paulo Da Silva

Graduate Theses and Dissertations

Root-lesion nematodes (Pratylenchus spp.) are migratory endoparasites of a variety of hosts worldwide. They are among the most common parasitic nematodes that feed on maize roots at all plant growth stages. Maize seedlings also are commonly attacked by pathogenic fungi and Oomycetes. The combination of nematode and fungus often results in a synergistic interaction wherein the crop loss is greater than expected from either pathogen alone or an additive effect of the two together. These interactions have been described from several crops, but lesion nematode-seedling pathogen interactions on maize (Zea mays L.) have not been intensively studied. Developments in seed ...


Isolation And Characterization Of A Fusarium Virguliforme Toxin That Induces Foliar Sudden Death Syndrome In Soybean [Glycine Max (L.) Merr.], Hargeet Kaur Brar Jan 2010

Isolation And Characterization Of A Fusarium Virguliforme Toxin That Induces Foliar Sudden Death Syndrome In Soybean [Glycine Max (L.) Merr.], Hargeet Kaur Brar

Graduate Theses and Dissertations

Fusarium virguliforme (Fv) is the causal organism of the sudden death syndrome (SDS) in soybean (Glycine max [L.] Merr). The estimated average annual soybean yield loss from this disease is valued at about 300 million dollars. F. virguliforme is a soil borne fungus, which attacks soybean roots and causes root rot as well as chlorosis and necrosis in foliar tissues. The pathogen has never been isolated from the diseased foliar tissues. It was therefore hypothesized that a toxin(s) is involved in the development of the disease.

Cell–free F. virguliforme culture filtrate containing one or more toxins produces foliar ...


Agronomic And Phenotypic Responses To 75 Years Of Recurrent Selection For Yield In The Iowa Stiff Stalk Synthetic Maize Population, Brent Howard Brekke Jan 2010

Agronomic And Phenotypic Responses To 75 Years Of Recurrent Selection For Yield In The Iowa Stiff Stalk Synthetic Maize Population, Brent Howard Brekke

Graduate Theses and Dissertations

The plant density at which Zea mays L. hybrids achieve maximum grain yield has increased throughout the hybrid era while grain yield on a per plant basis has increased little. Changes in plant traits including grain yield, moisture, test weight, stalk and root lodging, flag leaf angle, anthesis-silking interval(ASI), plant height, tassel branch number, and total number of leaves have been well characterized in comparisons of commercial hybrids representing different eras of hybrid maize production but have yet to be examined in a recurrent selection program.

The objective of this experiment was to determine if direct selection for grain ...


The Effects Of Previous-Year Corn Hybrid And Cropping System On Current-Year Corn Hybrids In Second Year Corn, Wade Adam Kent Jan 2010

The Effects Of Previous-Year Corn Hybrid And Cropping System On Current-Year Corn Hybrids In Second Year Corn, Wade Adam Kent

Graduate Theses and Dissertations

Grain yields decrease when corn (Zea mays L.) follows corn compared to corn grown in rotation with other crops. The factors that decrease grain yield of corn following corn are not well understood, and limit recommendations available to corn growers. Our objectives were to determine (i) if plant population, moisture, and yield of 2nd year corn are affected by the previous-year corn hybrid, (ii) evaluate if continued use of single hybrid over two growing seasons influences grain yield, and (iii) compare 2nd year corn yields to corn grown in rotation with soybean. The experiment was conducted at six ...


Novel Components Of Pseudomonas Putida Biofilm Exopolymeric Matrix And A Transcriptome Analysis Of The Effects Of Osmotic And Matric Stress, Lindsey Nielsen Jan 2010

Novel Components Of Pseudomonas Putida Biofilm Exopolymeric Matrix And A Transcriptome Analysis Of The Effects Of Osmotic And Matric Stress, Lindsey Nielsen

Graduate Theses and Dissertations

Bacteria have the reputation of being `simple' life forms based on their single cell nature and lack of a nucleus. However, no other domain on earth contains species that are so diverse in their metabolic and physiological capabilities allowing them to persist in environmental conditions inhospitable to many plants and animals. The key ability to persist in these environments lies in how cells are able to sense and respond to changes in their abiotic conditions. Nutrient abundance, pH, temperature, oxygen, redox state, and water availability are six major factors that are essential for all life. In soil habitats the availability ...


Agronomic And Seed Traits Of Soybean Lines With The Rag1 Gene For Aphid Resistance, Justin Lee Mardorf Jan 2010

Agronomic And Seed Traits Of Soybean Lines With The Rag1 Gene For Aphid Resistance, Justin Lee Mardorf

Graduate Theses and Dissertations

Soybean [Glycine max (L.) Merrill] yields can be reduced significantly by infestations of the soybean aphid (Aphis glycines Matsumura). A dominant allele, Rag1, providing resistance to the aphid was identified in PI 548663. The objective of this study was to compare the agronomic and seed traits of 27 BC2F2-derived lines with the Rag1 allele to those of 27 lines with the rag1 allele from the same segregating population. The lines were evaluated under aphid-infested conditions at two Iowa environments in 2008 and under aphid-infested and aphid-free conditions at three Iowa environments during 2009. There were significant differences in mean yield ...


Soybean Seedling Emergence And Yield In The Presence Of Fusarium Virguliforme, Brent James Pacha Jan 2010

Soybean Seedling Emergence And Yield In The Presence Of Fusarium Virguliforme, Brent James Pacha

Graduate Theses and Dissertations

The development of sudden death syndrome (SDS) in Iowa soybean production has progressively increased since being first observed in 1993. Movement of the disease from the Southern United States has brought along with it the agronomic recommendations for management of SDS, however these recommendations have not been investigated in Iowa. This research is part of a number of studies focused on developing agronomic recommendations for the management of SDS in Iowa. The particular studies in this work are focused on the management of the causal organism of SDS Fusarium virguliforme. Chapter two is a literature review of past SDS research ...


Interactions Among Viruses, Insect Vectors And The Phomopsis Complex In Soybean, And Effects Of Integrated Management Strategies, Jose Pablo Soto-Arias Jan 2010

Interactions Among Viruses, Insect Vectors And The Phomopsis Complex In Soybean, And Effects Of Integrated Management Strategies, Jose Pablo Soto-Arias

Graduate Theses and Dissertations

Bean pod mottle virus (BPMV), Soybean mosaic virus (SMV), bean leaf beetles (Cerotoma trifurcata), soybean aphids (Aphis glycines) and Phomopsis spp. all affect soybean seed quality in addition to causing yield losses. However, interactions among these pests and pathogens, and the effects of combined management practices, are not well understood. Infection of soybean plants by BPMV and SMV has been reported to increase their susceptibility to seed infection by Phomopsis spp., but the mechanism of predisposition is unclear. The overall goal of this research was to better understand the interactions between these soybean viruses and Phomopsis spp., and to assess ...


Evaluation Of An Uncalibrated Agricultural Land Model At The Sub-Field Scale, Jason C. Patton Jan 2010

Evaluation Of An Uncalibrated Agricultural Land Model At The Sub-Field Scale, Jason C. Patton

Graduate Theses and Dissertations

An uncalibrated agricultural land surface model, Agro-IBIS, was validated at the sub-field scale using data collected at a local agricultural field site planted with maize in 2009, with a focus on capturing the spatial variability and accumulation rates of soil moisture and leaf area index. Capturing the variability was deemed important for evaluating the model's potential for inclusion as the land surface model in atmospheric models. An ensemble method of forcing the model with different combinations of input data was used in an attempt to produce the variability seen in measurements across the field. The model was able to ...


Deacclimation Response To Winter Temperature Fluctuations In Lolium Perenne, Jacqueline Farrell Jan 2010

Deacclimation Response To Winter Temperature Fluctuations In Lolium Perenne, Jacqueline Farrell

Graduate Theses and Dissertations

Studies on climate change have shown an increase in not only the average global surface temperature but also an increase in extreme weather events. One such extreme weather event is the occurrence of winter temperature fluctuations, which can induce loss of cold acclimation. Sudden temperature fluctuations have occurred in the United States in the early spring of 2007 and the late winter of 2009. Both events caused significant freezing damage to plants. However, plants that were able to maintain a portion of their original freezing tolerance, by a process called deacclimation resistance, did not suffer significant damage.

Different phenotypic assays ...


Genetic Characterization Of The Partial Restorer Of Fertility Gene, Rf8, In T Cytoplasm Maize, Julie Marie Meyer Jan 2010

Genetic Characterization Of The Partial Restorer Of Fertility Gene, Rf8, In T Cytoplasm Maize, Julie Marie Meyer

Graduate Theses and Dissertations

Texas (T) cytoplasm maize (Zea mays L.) is a model system for studying cytoplasmic male sterility and fertility restoration. The mitochondrial gene responsible for male sterility is T-urf13. Fertility is restored to T cytoplasm maize by the combined action of two nuclear genes, Rf1 and Rf2a. Rf1 is associated with the accumulation of additional 1.6/0.6 kb T-urf13 transcripts while Rf2a is an aldehyde dehydrogenase and not involved in transcript accumulation. There are also partial restorers of fertility for T cytoplasm. Rf8 and Rf*, with the combined action of Rf2a, restore partial fertility and are associated ...


Tillage Effects On Soybean Growth, Development, And Yield, Alecia Marie Kiszonas Jan 2010

Tillage Effects On Soybean Growth, Development, And Yield, Alecia Marie Kiszonas

Graduate Theses and Dissertations

Profit margins of soybean [Glycine max (L.) Merr.] in the United States have recently declined as a result of an increase in production and land costs. Decreased profits coupled with increasing environmental concerns such as erosion and runoff prompts more cost-efficient production practices. No-tillage production practices offer a lower cost of production in addition to decreased soil erosion and runoff. Additionally, soil quality can be improved over time in a no-tillage system, greatly increasing the yield benefits over time. Today, only 41% of Iowa's soybean production is under no-tillage production (Conservation Technology Information Center, 2010), although even more of ...


Ophiostomatales Isolated From Two European Bark Beetles, Hylurgus Ligniperda And Orthotomicus Erosus, In California, Sujin Kim Jan 2010

Ophiostomatales Isolated From Two European Bark Beetles, Hylurgus Ligniperda And Orthotomicus Erosus, In California, Sujin Kim

Graduate Theses and Dissertations

Two European pine-infesting bark beetles, Hylurgus ligniperda and Orthotomicus erosus, were first detected in July 2003 in Los Angeles, California and in May 2004 in the Central Valley of California, respectively. These bark beetles (Coleoptera: Curculionidae: Scolytinae) are common vectors of fungi in the Ophiostomatales, some of which are tree pathogens or causal agents of blue stain of conifer sapwood. Ophiostomatales were isolated on a cycloheximide-amended medium, which is semi-selective for the growth of Ophiostoma and related genera. In total, eight identified species and seven unidentified species of Ophiostomatales were isolated from 118 adults of H. ligniperda collected from infested ...


Weed Growth In Conventional And Low-Input Cropping Systems, Rachel Beverly Halbach Jan 2010

Weed Growth In Conventional And Low-Input Cropping Systems, Rachel Beverly Halbach

Graduate Theses and Dissertations

We evaluated the effects of two rotational cropping systems in the soybean year on the growth of common waterhemp, common lambsquarters, giant ragweed, and velvetleaf in Central Iowa. The first experiment evaluated emergence of the four species. Common waterhemp emergence in the two-year system was more than twice that in the four-year system in 2008, whereas giant ragweed emergence was 1.7X greater in the four-year system in 2008. No other differences were observed in cumulative emergence.

A second study evaluated the growth and biomass production of the four weed species when seeds were planted at soybean planting and when ...


Agronomic And Seed Traits Of Soybean Lines With High-Oleate Concentration, Ryan Christopher Brace Jan 2010

Agronomic And Seed Traits Of Soybean Lines With High-Oleate Concentration, Ryan Christopher Brace

Graduate Theses and Dissertations

Soybean [Glycine max (L.) Merr.] oils with high-oleate (HO) or low linolenate (LL) concentrations have greater oxidative stability and longer shelf-life than conventional soybean oil. Soybean lines with the transgenic event DP-305423-1 produce a high-oleate oil and those with the fan1(C1640) and fan3(RG10) alleles produce a low-linolenate oil. The objective of this study was to evaluate the agronomic and seed traits of high-oleate/low-linolenate (HOLL) lines, high-oleate/normal-linolenate (HONL) lines, and normal-oleate/normal-linolenate (NONL) lines selected from four single-cross populations formed by crossing a HOLL parent homozygous for the transgene and the two fan alleles to four conventional ...


Phosphorus Sorption-Desorption Of Soils And Sediments In The Rathbun Lake Watershed, Najphak Hongthanat Jan 2010

Phosphorus Sorption-Desorption Of Soils And Sediments In The Rathbun Lake Watershed, Najphak Hongthanat

Graduate Theses and Dissertations

Livestock grazing in pastures has been identified as a possible factor controlling sediment and phosphorus (P) delivery to Rathbun Lake and associated water bodies in the watershed. The risk of P loss from soils in this watershed was estimated by Mehlich-3 (M3) extractable P, P sorption indices (Smax and k), degree of P saturation (DPS) and P desorption indices (equilibrium phosphorus concentration (EPC) and phosphorus equilibrium buffering capacity (PEBC)) for seven representative soil samples. Most of selected soils had low risk of P loss as indicated by PM3 and DPS. However, EPC values indicated that some soils could ...


The Regulation Of Host Translation Initiation In Plant-Pathogen Interactions, Jackson Russell Moeller Jan 2010

The Regulation Of Host Translation Initiation In Plant-Pathogen Interactions, Jackson Russell Moeller

Graduate Theses and Dissertations

Pathogens dramatically alter plant mRNA transcript levels by activating and repressing a variety of signaling pathways. However, the effects of plant pathogens on host mRNA translation have not been explored on a genome-wide scale. To assess pathogen-induced changes in host mRNA transcription and translation, we conducted DNA microarray analysis of total and polyribosomal RNA fractions in the Arabidopsis thalianaTurnip mosaic virus (TuMV) and barley-powdery mildew (Hordeum vulgareBlumeria graminis f.sp. hordei (Bgh)) interactions. The ratios of mRNA transcript abundance in total versus polyribosomal RNA fractions were compared between inoculated and non-inoculated sample types to identify mRNAs that were ...


Alternative Weed Management Practices: Effects On Weed Control, Grapevine Performance, And Soil Quality In An Established Midwestern Vineyard, Lisa Marie Wasko Jan 2010

Alternative Weed Management Practices: Effects On Weed Control, Grapevine Performance, And Soil Quality In An Established Midwestern Vineyard, Lisa Marie Wasko

Graduate Theses and Dissertations

Sustainable grape production entails the implementation of management practices that control weeds, maintain grapevine performance, and conserve soil quality. Conventional weed management practices include herbicide application and/or cultivation. These practices compromise soil quality by limiting additions of organic matter and exposing the soil surface, thereby leaving it prone to degradative processes. With the expansion of continental climate viticulture in areas with rain-fed agriculture, such as in the Midwest, there is a need for sustainable weed management practices that optimize production while conserving soil quality. The primary objective of this investigation was to evaluate weed management practices in an established ...


Native Warm-Season Grasses: Species, Nitrogen Fertilization, And Harvest Date Effects On Biomass Yield And Composition, Naroon Waramit Jan 2010

Native Warm-Season Grasses: Species, Nitrogen Fertilization, And Harvest Date Effects On Biomass Yield And Composition, Naroon Waramit

Graduate Theses and Dissertations

For traditional forage use, native warm-season grasses are highly productive in the summer months and are suited for a complementary role with cool-season forages in full-season forage systems of the Midwest. For renewable energy sources, these grasses can be used to produce biofuels, an alternative energy source in the future for fossil fuel which is becoming less available. Farmers may integrate forage and biomass cropping for flexibility and diversity in their farming systems. For dual-purpose crops (forage or biomass), the production of warm-season grasses would provide farmers some protection against the market failure of a single purpose. The goals for ...


Soybean Improvement Strategies: Insect-Pollinator Attraction And Genetic Resistance To Whitefly And To Brown Stem Rot, Paola T. Perez Jan 2010

Soybean Improvement Strategies: Insect-Pollinator Attraction And Genetic Resistance To Whitefly And To Brown Stem Rot, Paola T. Perez

Graduate Theses and Dissertations

Soybean [Glycine max (L.) Merr.] is one of the most important plants cultivated worldwide. It is a source of oil and protein and is used for livestock feed, human food, and also for industry. Over the years, yield increases have been accomplished due to genetic improvement and enhancement of agronomic practices. The purpose of this research project was to investigate different strategies for soybean improvement, from genetic resistance to biotic stresses, to surveying perennial wild relatives for insect-pollinator attraction characteristics that could be useful in hybrid seed production in the cultivated species. The first objective of this research was to ...


The Agronomic And Economic Performance Of Flax In Iowa, Stefans Robert Gailans Jan 2010

The Agronomic And Economic Performance Of Flax In Iowa, Stefans Robert Gailans

Graduate Theses and Dissertations

Demand for flax (Linum usitatissimum L.) has increased due to the discovered health benefits of adding flaxseed to human diets. A facility in northwest Iowa that processes organic flaxseed for oil provides a viable market for organic growers in the Midwest. Organic growers are particularly concerned about adequate fertility and weed management when adding flax to their crop rotations. Our objective was to evaluate flax response to N rate and source as well as to ambient weed competition when following either soybean or corn in rotation. The particular response variables investigated were seed yield, straw yield, harvest index, oil concentration ...


Double-Cropping Sorghum For Biomass Production, Ben Michael Goff Jan 2010

Double-Cropping Sorghum For Biomass Production, Ben Michael Goff

Graduate Theses and Dissertations

The production of biomass using double-cropping systems may have the advantage of producing more feedstock for refineries by extending the growing season, while also providing many environmental benefits, such as the reduction of erosion. Past research indicates that there may be a genotypic effect for the suitability of a crop for use within these systems. There has been little research conducted to explicitly examine this effect in sorghum, despite the crop's diverse genetic background. The objective of this study was to evaluate the biomass production of twelve sorghum genotypes grown as a sole crop and within a double-cropping system ...


Fifty Years Of Agricultural Soil Change In Iowa, Jessica Veenstra Jan 2010

Fifty Years Of Agricultural Soil Change In Iowa, Jessica Veenstra

Graduate Theses and Dissertations

Many scientists have studied agricultural soil change. Most of these studies focus on changes in the surface 0 to 30 cm soil. Despite a whole body of scientific research that shows that soils change on relatively short time scales under different management regimes, classical pedological theory states that we should expect these changes to occur only in the surface few centimeters and that they are not of adequate magnitude to suggest fundamental changes in pedon character over short periods of time. Nevertheless, when we resampled sites that were initially described by the soil survey between 1943 and 1963 and compared ...


Characterization Of Soybean Gmpub1 Proteins That Interact With The Phytophthora Sojae Effector Avr1b Protein, Shan Li Jan 2010

Characterization Of Soybean Gmpub1 Proteins That Interact With The Phytophthora Sojae Effector Avr1b Protein, Shan Li

Graduate Theses and Dissertations

Phytophthora sojae is an oomycete which causes stem and root rot disease in soybean. Upon infection, P. sojae could deliver a series of virulent effector proteins into host cell to promote disease on susceptible plants (Tyler et al. 2008, Gyhre and Robatzek 2008). Avr1b is one such protein (Tyler et al. 2008). In this report, a soybean U-box protein, GmPUB1-1, was isolated by interaction with P. sojae effector Avr1b in yeast. It has a homologous copy which was named GmPUB1-2. These two GmPUB1 proteins share 94% identities. Pull-down assay confirmed the interaction between GmPUB1s and Avr1b in vitro. Mutations in ...


Quantifying The Aggressiveness, Temporal And Spatial Spread Of Pantoea Stewartii In Sweet Corn, Lu Liu Jan 2010

Quantifying The Aggressiveness, Temporal And Spatial Spread Of Pantoea Stewartii In Sweet Corn, Lu Liu

Graduate Theses and Dissertations

Stewart's disease, caused by Pantoea stewartii (Smith), can cause severe economic damage to seed nd sweet corn crops due to phytosanitary regulations that prevent the export of seed corn, as well as causing direct reductions in yield. To date, there are no quantitative data on the aggressiveness of P. stewartii isolates at the plant scale, nor on the temporal and spatial spread of this pathogen in the field. To quantify and compare the effect of temperature, leaf position (age) and isolate on the aggressiveness of P. stewartii isolates, growth chamber experiments were conducted using the sweet corn variety Jubilee ...


Comparing Inter-Specific Competition For Continuous Corn Grown In A Living Mulch With Stover Removal, Dustin R. Wiggans Jan 2010

Comparing Inter-Specific Competition For Continuous Corn Grown In A Living Mulch With Stover Removal, Dustin R. Wiggans

Graduate Theses and Dissertations

Chapter 3: Agronomic Response of Living Mulches in Continuous Corn with Stover Removal

A paper to be submitted to Agronomy Journal

Dustin R. Wiggans, Jeremy W. Singer, Kenneth J. Moore, and Kendall R. Lamkey

Corn stover provides producers a potential additional market for selling biomass for biomass production. However, corn stover returns nutrients to the soil, decreases soil erosion, and helps maintain soil properties. Long term stover removal has been determined to cause detrimental environmental effects (Wilhelm et al., 1986; Mann et al., 2002; Nelson, 2002). Perennial groundcovers or living mulches grow simultaneously with the main row crop and are ...


Grain Amaranth Production And Effects Of Soil Amendments In Uganda, Michael William Graham Jan 2010

Grain Amaranth Production And Effects Of Soil Amendments In Uganda, Michael William Graham

Graduate Theses and Dissertations

Grain amaranths (Amaranthus spp.) are high protein content and quality pseudo-cereal crops originally domesticated in Latin America whose favorable nutritional profile belies their potential to alleviate nutrition and food insecurity in developing countries. Grain amaranth was introduced as a nutrient dense food into the Kamuli District, eastern Uganda, in 2006 through Iowa State University's Center for Sustainable Rural Livelihoods (CSRL) in conjunction with Ugandan partners Volunteer Efforts for a Development Concerns (VEDCO), a local non-governmental organization (NGO), and Makerere University. Initial analysis of protein content of amaranth grain pooled from farms in the Kamuli District indicated protein levels from ...


Numerical Modeling Of Meteorological And Topographical Effects On Pollen Shed, Dispersion, And Viability, Brian Viner Jan 2010

Numerical Modeling Of Meteorological And Topographical Effects On Pollen Shed, Dispersion, And Viability, Brian Viner

Graduate Theses and Dissertations

For open-pollinated species, the success of a pollen grain pollinating a receptive plant is a function of when it is shed, its dispersion in the atmosphere, and the chance of germination upon deposition. Most studies of pollen dispersion have focused on a source and surrounding fields in relatively flat terrain, but dispersion to distances over 20 km has been reported in regions of complex terrain. For this reason, a more detailed examination of atmospheric dispersion over long distances and the components of dispersion - shed, transport, and successful pollination - was undertaken. This dissertation uses numerical models to predict these components in ...