Other Plant Sciences Commons^™

Evaluation Of Ultraviolet-C Light For Control Of Mites And Western Tarnished Plant Bug In Strawberry & Interactive Lethal Effects Of Common Strawberry Fungicides And Adjuvants On Phytoseiulus Persimilis, Colin T. Koubek

Master's Theses

California strawberry production relies heavily on chemical pesticides to manage arthropod pests and diseases, but pesticide resistance, regulatory pressure, and the need to conserve biological control agents have increased interest in alternative pest management tools. This thesis evaluated ultraviolet-C (UV-C) light as a nonchemical management tool for key strawberry arthropod pests and assessed the compatibility of common strawberry fungicides and adjuvants with the predatory mite Phytoseiulus persimilis Athias-Henriot. The first objective was to determine the ovicidal and lethal effects of UV-C light on Lygus hesperus Knight eggs and nymphs. Laboratory and field ovicide assays were conducted using UV-C doses relevant …

Reassessment Of Species Boundaries And Phylogenetic Relationships In The Desmodium Ciliare Complex (Fabaceae) Using Morphological And Dna Data, Joshua Wilkinson

Master's Theses

Desmodium (Beggar's ticks) is a generally weedy genus of approximately 280 species in the angiosperm family Fabaceae (Subfamily Papilionoideae, Tribe Desmodieae) characterized by indehiscent loments constricted into segments. Within the Southeastern U.S., the Desmodium ciliare group is one of two Desmodium species complexes that have been historically difficult, with much argument about the limits of species and the role of hybridization. There are three commonly recognized species within the D. ciliare group, D. ciliare (Muhl. ex Willd.) DC., Desmodium marilandicum (L.) DC., and D. obtusum (Muhl. ex Willd.) DC., with two supposed hybrids in addition to the …

Evaluation Of Masculinization Treatments To Produce Feminized Hemp Seed (Cannabis Sativa L.), Ted Fitzgerald, J. Wyatt Brown

Master's Theses

Cannabis sativa L. (hemp) develops plants with either male or female flowers, and growers of hemp greatly prefer female flowers which bear the glandular trichomes that contain cannabinoids. Feminized (all female) seeds are highly desired, which are produced by crossing a female plant with a masculinized female plant. Masculinization is achieved through the inhibition of ethylene and/or addition of gibberellins before flower initiation in female plants. The hemp industry uses silver thiosulfate (STS) to masculinize hemp, but spraying silver poses environmental concerns. This study compared STS to three other ethylene-inhibiting agents: aminoethoxyvinylglycine (AVG), cobalt nitrate (CBN), and 1-methylcyclopropene (1-MCP). Treatments …

Attractiveness Of English Thyme (Thymus Vulgaris L.) To Arthropod Natural Enemies And Its Suitability As A Dual Use Resource, Kristina K. Van Wert

Master's Theses

Current agroecosystem management practices have a negative effect on natural enemies and their ability to control insect pests. Conservation biological control through the addition of flowering resources can manage food resources for natural enemies. These floral resources can also provide multiple ecosystem services. Study goals were to determine if perennial Thymus vulgaris L. was attractive to natural enemies and if so, could it be a dual use resource encouraging pest management and providing harvestable product. In 2018 plots in three locations were used to examine the effect of habitat throughout the growing season on the attractiveness of T. vulgaris. …

Factors Affecting The Regrowth Of Ilex Glabra In A Routinely Burned Longleaf Forest, Jaybus Price

Master's Theses

This study examines the effects of historical management by use of prescribed fire on Ilex glabra stems/m² and factors affecting the regrowth of I. glabra after a prescribed burn to gain beneficial knowledge for management purposes. Environmental factors and morphological parameters of I. glabra were sampled before and after a prescribed burn of the Longleaf Trace Nature Preserve in September 2016. The study site is located in Lamar County, Mississippi, just west of Hattiesburg, MS. Stem densities of I. glabra were collected once before the prescribed burn and twice after the prescribed burn at 2 month and 9 month …

A Comparative Analysis Of The Nutrient Composition And Digestibility Of California Perennial And Annual Grasses At Four Stages Of Growth, Elaina Cromer

Master's Theses

Beef products represent the fourth largest agricultural commodity in the state of California, valuing more than $3 billion from 2013 to 2015 (CDFA, 2016) and procure 90% of the income for the range livestock industry (FRAP, 2003). Forages found on California’s coastal, desert, foothill, and mountain ranges are the basis of the state’s beef cattle industry. Understanding their nutritional quality of these forages is important for their effective use (George et al., 2001a; Waterman et al., 2014). The objectives of this research were to investigate the nutritional characteristics, and in situ digestbilities in Angus beef cattle, of common California annual …

Effects Of Recycled Water On Landscape Plants, Casey R. Miranda

Master's Theses

ABSTRACT EFFECTS OF RECYCLED WATER ON LANDSCAPE PLANTS Casey Ray Miranda Recycled water is water that has been previously used, has suffered a loss of quality, and has been properly treated for redistribution (Wu et al. 2001). The use of recycled water as an alternative to fresh water in the landscape can have positive and negative effects. Experimentation on 40 different plant species during a 32 week period (2 phases of 16 weeks), was conducted to analyze the effects of recycled water irrigation on the appearance of landscape plants. Each species of plant was planted into 10 individual number 2 …

Impact Of Weed Management Practices On Grapevine Growth, Yield Components, Plant And Arthropod Abundance, And Carabid Seed Predation In Paso Robles Vineyard, Paolo Sanguankeo

Master's Theses

In the Central Coast of California, USA, wine grape growers are making efforts to identify weed control practices that promote biodiversity in their vineyards while maintaining yields. A field study was conducted in Paso Robles, CA in 2006 and 2007 evaluating the effect on Zinfandel grape-vine growth and production, groundcover plant, and ground dwelling arthropod communities of five weed control practices: 1) flumioxazin, 2) simazine, 3) cultivation, 4) cover crop, and 5) untreated control.

The herbicide treatments had the lowest weed biomass followed by the cultivation, being approximately 10 and 2 times lower than the weed biomass of either the …

Plant Growth Regulator Sprays And Girdling: Potential Horticultural Techniques To Increase Fruit Retention And Yield Of Longan (Dimocarpus Longan Lour.) Trees In California, Leila Anne Graves

Master's Theses

Abstract Plant Growth Regulator Sprays and Girdling: Potential Horticultural Techniques to Increase Fruit Retention and Yield of Longan (Dimocarpus longan Lour.) Trees in California Leila Graves June 2009 The longan is a subtropical fruit tree whose popularity is growing quickly among American consumers, and thus, could become a lucrative niche market for California growers. Trees planted as part of an initial variety trial conducted in commercial California orchards are beginning to bear fruit. However, fruit retention and yields are low due to excessive abscission during early fruit set. Horticultural techniques, such as plant growth regulator (PGR) sprays and girdling, often …