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Survey Of Native Predatory Hemipterans And Assessment Of Nabis Americoferus Carayon (Hemiptera: Nabidae) As A Biological Control Agent Of Lepidopteran Tomato Pests, Andrew Laflair

Electronic Theses and Dissertations

Invasive species have become a grave threat to the economic viability of our global vegetable producers. Tomato pinworm Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) has expanded from its range originating from Peru to being established in nearly hundreds of countries, causing tomato production losses of up to 100% on occasion; however, it has not yet been found in Canada or the USA. Southwestern Ontario is a significant tomato producer making it a high risk from this invasive species. Efficient integrated control methods such as native biological control agents (BCAs) that avoid creating insecticide resistance are ideal. Surveys of Southwestern Ontario conservation …

Developing Methods To Survey, Collect, Process, And Screen Endemic Entomopathogenic Fungi Against The Asian Citrus Psyllid In The Lower Rio Grande Valley, Jonathan Cisneros

Theses and Dissertations

The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vectors “Candidatus Liberibacter spp.”, the causative agent of Citrus Greening Disease. Managing ACP is imperative given the continuous increase in HLB positive trees. An aspect of integrated pest management (IPM) is the use of entomopathogenic fungi for the biological control of D. citri.

In order to identify endemic entomopathogenic fungi actively infecting D. citri, ACP were collected from local residential areas, surface sterilized, and plated on a semi-selective agar medium. Collection of over 9,300 samples from 278 sites throughout the LRGV led to the positive identification of …

Switchgrass Extractives Have Potential As A Value-Added Antimicrobial Against Plant Pathogens And Foodborne Pathogens, Alexander Ian Bruce

Masters Theses

Panicum virgatum (switchgrass), a perennial grass native to North America, is a leading biomass feedstock candidate for the manufacture of cellulosic ethanol. Switchgrass is considered a viable option for biofuel production due to its cheap production cost and ability to grow on marginal land. Biofuel derived from switchgrass has been shown to be very energy efficient, producing 540% more renewable energy versus nonrenewable energy expended. Switchgrass-derived biofuel is also estimated to have greenhouse gas emissions that are 94% lower than emissions from gasoline (Schmer et al 2008). Biofuels are created through biochemical processes that utilize various enzymes and microorganisms for …

Novel Advancements For Improving Sprout Safety, Kyle S. Landry

Doctoral Dissertations

All varieties of bean sprouts (mung bean, alfalfa, broccoli, and radish) are classified as a “super-food” and are common staples for health conscious consumers. Along with the proposed health benefits, there is also an inherent risk of foodborne illness. When sprouts are cooked, there is little risk of illness. The purpose of this dissertation was to explore novel techniques to minimize or prevent the incidence of foodborne illness associated with the consumption of sprouts. Three areas were investigated: 1) the use of a biocontrol organism, 2) the use of a novel spontaneous carvacrol nanoemulsion, and 3) the influence of the …

Biological Indicators Of Compost-Mediated Disease Suppression Against The Soilborne Plant Pathogen Rhizoctonia Solani, Lynn Fang

Graduate College Dissertations and Theses

Compost can suppress soilborne plant pathogens that cause significant damage on globally important food crops. However, reports of plant pathogen suppression are inconsistent likely because there are no established standards for feedstock material, application rate, and maturity age upon application. Excellent results can be achieved in greenhouse trials, but field applications are much less reliable. Disease suppression occurs through the activity of biocontrol organisms (direct antagonism), and general microbial competition. Biocontrol species are hypothesized to colonize the pile during the curing phase, but single species may not be as important as microbial consortia. Substrate composition during maturation may give rise …

Cultural Techniques To Improve Yield And Cost Efficiency Of Greenhouse Grown Tomatoes, Susannah Kate Amundson

Masters Theses

Tomatoes (Solanum lycopersicum) are the most commonly grown greenhouse vegetable crop, preferred for their high consumer demand and high value. To improve profitability, growers continuously seek new techniques to improve yield and cost efficiency of production. Four studies were conducted between Fall 2008 and Spring 2010 in greenhouses at the University of Tennessee Plateau Research and Education Center (35°56́ N lat.) and the University of Tennessee (35^o 57’38” N lat.) to investigate the impact different plant spacings (12, 16, 20, 24, or 28 inches in-row), pruning systems (one leader versus two leaders), cluster thinning (three, four, five, or …

Evaluation Of Drip Applications And Foliar Sprays Of The Biocontrol Product Actinovate On Powdery Mildew And Other Fungal Diseases Of Tomato, Therese Angelica Quintana-Jones

Master's Theses

The effectiveness of the biocontrol product Actinovate^® at enhancing tomato plant growth and yield, and reducing the presence of fungal pathogens was studied in greenhouse and field conditions. In the greenhouse, no differences were found among seed germination or plant survival rates, seedling heights, dry root weights, and dry shoot weights of tomato seedlings grown from seeds drenched with Actinovate^® or Rootshield^®. The effects of one initial Actinovate^® seed drench at sowing, repeated applications through the drip irrigation throughout the season, or repeated applications through the drip irrigation plus foliar applications throughout the season at …