Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Charles J. Barden / Contaminated water poses a major environmental and human health problem, which may be resolved by using the emerging phytoremediation technology. This plant-based cost-effective approach to remediation takes advantage of the ability of plants to concentrate elements and compounds from the environment, to absorb and transpire large amounts of water, and to metabolize various molecules in their tissues. The city of Manhattan’s Biosolids Farm located near Manhattan, Kansas is using the emerging technology of phytoremediation. The Biosolids Farm remediation began in the mid 1990’s; with a large planting of alfalfa with the goal of absorbing excess nitrates from soil and ground water. In 2004, hundreds of trees were planted, to serve as a protective buffer between the biosolids disposal area and the Kansas River. In 2006, a trench study was installed to improve tree establishment on a sandy outwash area close to the Kansas River using Siberian elm seedlings and rooted cottonwood cuttings from Nebraska and true cottonwood seedlings from Missouri. Treatments included trenching, dairy cattle composted manure, and tree shelters. This planting was done to serve as a vegetative barrier and to aid in reducing nitrate movement into the Kansas River. There were interaction between the tree sources and the trenching, compost and shelter treatments. The treatments showed significant interactions with tree sources with the addition of compost and shelters with a p value of 0.0438, and trenching and compost p-value 0.0021. Tree survival was significantly improved with the use of tree shelters.

Master of Science / Department of Entomology / Raymond A. Cloyd / Western flower thrips (WFT), Frankliniella occidentalis, is one of the most destructive insect pests of greenhouse production systems because of the direct and indirect damage they cause and their ability to develop resistance to a wide variety of insecticides. A common method of avoiding resistance development is by rotating insecticides that have different modes of action. Entomopathogenic organisms (EPO), such as fungi and bacteria, have modes of action that are very different from standard insecticides. Thus, by incorporating EPO into rotation programs, greenhouse producers may preserve the efficacy of insecticides used for suppression of WFT populations. Therefore, the objectives of this study were to 1) determine the efficacy of entomopathogenic fungi on WFT adults and nymphs, and to assess product effectiveness when used beyond the expiration date; 2) evaluate the efficacy of entomopathogenic fungi against WFT nymphs when combined with the insect growth regulator, azadirachtin; and 3) evaluate different rotation programs that include EPO and standard insecticides commonly used to suppress WFT populations. To satisfy objective one and two, a series of laboratory bioassays were conducted in which WFT nymphs and adults were exposed to three entomopathogenic fungi (Beauveria bassiana, Isaria fumosoroseus, and Metarhizium anisopliae) at two label rates (maximum and minimum), and two product conditions (fresh and expired). Furthermore, a bioassay in which each entomopathogenic fungi was tested with and without azadirachtin was conducted to determine if there was any synergistic effect on WFT nymphal mortality. Results indicated that adults are generally more susceptible to infection by entomopathogenic fungi than nymphs, fresh products resulted in higher mortality than expired products, and azadirachtin, when mixed with the entomopathogenic fungi, did not increase mortality of WFT nymphs except when combined with M. ansiopliae. Insecticide rotation programs that included EPO were evaluated by conducting a series of greenhouse experiments in which chrysanthemum, Dendranthema x morifolium plants were artificially infested with WFT adults. Eight-week rotation programs were applied to each plant and weekly counts of adults captured on yellow sticky cards were recorded. A final quality assessment of damage due to WFT feeding on foliage and flowers (1 to 5 in which 1 = no damage, and 5 = greater than 75% damage) was also recorded. In addition, a cost comparison of each rotation program was determined. Generally, insecticide rotations programs which incorporated EPO resulted in no significant difference in WFT populations compared to standard insecticide rotation programs without EPO. Furthermore, there were no significant differences between any of the rotation programs in regards to foliage and flower quality. Based on the results of the cost comparison, there may be a cost savings associated with using EPO. Therefore, by incorporating EPO into insecticide rotation programs, greenhouse producers may reduce costs as well as reduce selection pressure on WFT populations, which may avoid or delay resistance development.

Doctor of Philosophy / Department of Horticulture, Forestry, and Recreation Resources / Steven Keeley / Controlling and preventing the spread of silvery-thread moss (STM, Bryum argenteum Hedw.) in putting greens is a difficult task for superintendents. Once established, a STM infestation can quickly increase through the movement of asexual propagules, such as shoot fragments, bulbils and protonema. Many practices used by superintendents are likely aiding in the dispersal and establishment of propagules. Research is needed to help superintendents effectively control this very invasive pest. The objectives of this research were to: 1) Investigate the cumulative effect of cultivation on a STM infestation in a creeping bentgrass putting green, when used with or without light, frequent topdressing and the herbicide carfentrazone; 2) Determine if STM growth is reduced by spraying ammonium sulfate (AMS) compared to urea, and understand the effect of spray volume on STM growth; 3) Evaluate the effectiveness of a range of carfentrazone rates for postemergence STM control; and 4) Determine if altering the pH of irrigation water with sulfuric- or hydrochloric acid affects the growth of STM. Generally, cultivation and carfentrazone reduced STM cover; however, the greatest reduction in STM cover was achieved when cultivation treatments were used in conjunction with carfentrazone. Topdressing did not affect STM cover. Ammonium sulfate increased STM cover and dry weight compared to urea and an untreated control. Furthermore, spray volume did not affect STM cover at any rating date. Superintendents managing STM infestations should limit or avoid use of AMS as an N source. At 28 days after treatment (DAT) the ED[subscript]90 (dose required to cause 90% gametophyte injury) was 26.8 g ai ha[superscript]-1, and at 49 DAT ED[subscript]90 was 54.3 g ai ha[superscript]-1; both of these doses are substantially lower than the label rates for long- and short-term control, respectively. As compared with label recommendations, this research suggests lower carfentrazone rates, and longer intervals, may be effective for STM control in putting greens. Irrigation pH affected STM growth, with pH’s 5 and 6 having increased growth compared to pH’s 7 and 8. It was hypothesized a lower irrigation pH enabled STM to better withstand sodium stress.

The study’s aim was to determine how consumers relate to specific factors that affect the way in which fruit is marketed in supermarkets. This might have an influence on effective commercialization of new intellectual property in the global avocado industry.

The study’s aim was to determine how consumers relate to specific factors that affect the way in which fruit is marketed in supermarkets. This might have an influence on effective commercialization of new intellectual property in the global avocado industry.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Master of Science / Department of Horticulture, Forestry, and Recreation Resources / Cheryl R. Boyer / Pine bark (PB) has been the principal component of nursery crop substrates in the United States for more than 60 years. Substrate material used for the purpose of growing ornamental plants in the Great Plains is generally shipped a great distance, primarily from the Southeastern U.S., due to a lack of pine plantations in this region. Eastern redcedar (Juniperus virginiana L.; ERC), an aggressively weedy tree species, has been identified as a possible alternative to PB for nursery substrates. The objective of this thesis was to evaluate the establishment of Miscanthus sinensis N.J. ‘Little Kitten’ (dwarf maiden grass), Rosa (L.) ‘Radtkopink’ (Knockout® rose), Ilex glabra (L.) A. Gray ‘Compacta’ (holly), Ulmus parvifolia Jacq. ‘Emer II’ (Allee® lacebark elm), Sedum telphium L. ‘Autumn Joy’ (sedum), Hosta Tratt. ‘Sum and Substance’ (hosta), and Hemerocallis L. ‘Charles Johnston’ (daylily) in three substrate mixes. These substrate mixes consisted of 80% PB: 20% sand, 80% ERC: 20% sand, and 40% PB: 40% ERC: 20% sand. At the end of the production phase differences in growth were observed in maiden grass, holly, lacebark elm, and sedum. At the end of the landscape establishment phase, no differences in growth were observed in any species except holly and hosta. To attempt to overcome the sub-optimal physical properties of ERC (high air space and low container capacity), cyclic irrigation was used to evaluate growth of Sedum spectabile Boreau ‘Autumn Fire’ (sedum), Rudbeckia fulgida Aiton ‘Goldstrum’ (black-eyed susan), and Hibiscus moscheutos L. ‘Luna White’ (hibiscus) in the same 3 substrates. The objective of this study was to evaluate the affect of irrigation frequency (1x, 2x, 3x, or 6x per day) and substrate ERC content on plant growth. Sedum had the greatest growth index (GI) shoot dry weight in PB and when irrigated 1x and 2x per day had the greatest root dry weight regardless of substrate. Irrigation frequency had no significant difference for GI and shoot dry weight Black-eyed susan had the greatest GI and shoot dry weight when grown in PB. Irrigation frequency only had an impact on shoot dry weight of black-eyed susan; plants irrigated 1x, 2x, and 3x per day had the greatest growth. Hibiscus had greatest growth in PB: ERC mix. Irrigation frequency had no impact on growth of hibiscus. Cyclic irrigation does not overcome low water holding capacities in these three species. Overall, ERC can be used as a partial replacement to PB (up to 50%). However, further research evaluating effects of different fertility regimes on ERC substrate is warranted.

Master of Science / Department of Plant Pathology / Megan Kennelly / Dollar spot disease of turfgrass, caused by the fungus Sclerotinia homoeocarpa, is the most economically important disease of intensively managed turfgrass such as creeping bentgrass (Agrostis stolonifera) in golf course fairways and putting greens. While several cultural management practices can lessen the severity of the disease, fungicide applications are necessary to manage the disease to acceptable levels. Host resistance is another avenue of improving the quality of turfgrass in response to dollar spot disease, but more information on cultivar susceptibility levels is necessary. Many fungicides are available to control dollar spot, but S. homoeocarpa has shown resistance to both demethylation inhibitor (DMI) and benzimidazole class fungicides. The objectives of this thesis were: (1) to evaluate 15 cultivars of creeping bentgrass under putting green and fairway management for both overall quality and disease severity of dollar spot in the presence and absence of fungicide applications; (2) to determine the sensitivity of Kansas S. homoeocarpa isolates to the DMI fungicides propiconazole, metconazole, tebuconazole, and triticonazole using in vitro mycelia growth assays; (3 to determine a best discriminatory dose concentration for each DMI fungicide that will provide for rapid testing of relative sensitivity, and (4) to sequence the entire β-tubulin gene of several resistant and sensitive isolates to determine mutations associated with resistance. There were differences in turfgrass quality among the 15 cultivars at putting green height but not fairway height. There were no significant differences in disease. In the fungicide resistance assays, the mean EC50 values were 0.0163, 0.038, 0.0612, and 0.0994 µg/ml for metconazole, propiconazole, tebuconazole, and triticonazole, respectively. Correlations were significant and positive for all pairwise comparisons of log10EC50 values. Regressions using discriminatory concentrations tested were significant. The most predictive concentrations were 0.01, 0.05, 0.05, and 0.10 µg/ml a.i, for metconazole, propiconazole, tebuconazole, and triticonazole, respectively. The entire β-tubulin gene was sequenced for four resistant and four sensitive isolates. The resistant isolates all harbored a substitution of alanine for glutamic acid at codon 198 (E198A).

Master of Science / Department of Horticulture, Forestry, and Recreational Resources / Rhonda Janke / With the increasing popularity of urban farming, more people are seeking resources to start their own farming/growing production in urban environments. Traditionally, county Extension educators are a key resource for beginning farmers and growers. However, urban Extension offices are often overlooked as resources in the urban farming planning process. The objectives of this study are 1) identify information urban farmers currently have, information they need, and their preferred delivery methods 2) look at the resources and information that are offered by local Extension educators in the KC metro area and 3) analyze how these two groups are communicating and what could improve to meet farmers‟ needs. This project evaluates current interaction between urban farmers and Extension educators in the Kansas City area through a two-pronged approach: a written mail-out questionnaire for urban farmers and growers in the Kansas City metropolitan area and through in-person one-on-one interviews with Extension educators that emphasize topic areas related to urban agriculture in the KC area. One hundred and nineteen farmers/growers were surveyed, and a 54.6% response rate was achieved. The majority of farmers had small, diversified farms and were relatively new to farming. Respondents were primarily older, white men that had higher education. Independently-driven sources (such as self-research, other farmers, and friends/family) were most commonly used sources among farmers. Overall, respondents ranked Extension highly in terms of information quantity, quality and as their "go to" source. Extension educators from Kansas State University, University of Missouri, and Lincoln University were interviewed one-on-one using scripted interview questions to determine topics and medias of information that are currently being offered. Production and processing information is offered the most by educators followed by distribution, equipment, and marketing information. Financial information was the least offered information topic. Extension educators use a wide variety of methods to distribute information. Most Extension educators are aware of benefits and barriers relating to urban agriculture in the KC metro area. Extension educators are addressing urban agriculture in varying degrees and the level of involvement corresponds to the Extension institution.

Thesis (MTech (Horticulture))--Cape Technikon, Cape Town, 1999 / Vegetative propagation techniques for rooting of cuttings of indigenous tree species, i.e. Olea europaea subsp. African, Podocarpus falcatus, Syzigium cordatum and introduced species, i.e. Acacia mearnsii, A. melanoxylon, Eucalyptus grandis and Melia azedarach were studied and improved at the Cape Technikon nursery from May 1994 to June 1998. These tree species are considered problematic since the indigenous species produce unwanted fruits in urban areas which attract frugivores, while the introduced species are a threat to indigenous vegetation and natural habitats, though they are of great commercial value. The progress in mutation breeding of sexual sterility in most of the problematic species created a need to propagate them vegetatively. Without cloning of seedless species, their beauty and economic value to South Africa will be lost, as the indigenous species will be neglected, while invasive species will continue to threaten the natural habitat of indigenous species. Experiments were conducted to test age, type and length of cuttings, environmental factors, growth season, hormone application, various treatments and rooting media for each of these species. This study showed that relatively few publications relevant to the vegetative propagation of indigenous tree species are available. However, some introduced species, e.g. Eucalyptus grandis, are propagated successfully for commercial forestry purposes. Ficus sur and Syzicium cordatum showed the highest rooting success, i.e. 85-90%, followed by Olea europaea subsp. africana (75-80%), and Podocarpus falcatus (60%). The introduced species showed no rooting success, however, callusing in Eucalyptus grandis (35-61%), and Melia azedarach (50%), and survival rates in Acacia mearnsii (10%) and A. melanoxylon (20%) were achieved. Treatments, i.e. etiolation, placing plants under stress, sealing basal stems of cuttings, and fungicide treatments all showed positive results in promoting callusing success. The study showed that rooting success in individual species are directly related to the growth stage of parent plants as well as the season during which the cuttings were taken. With progress towards successful vegetative propagation of sterile problem plant species, propagators and horticulturists can in future apply these improved techniques. These plants will then continue to supply timber, fire wood and improve aesthetics in the South African urban environment.