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Full-Text Articles in Life Sciences

Classifying And Mapping Diversity In A Species-Poor System: The Mangrove Meta-Community Of Laguna Chacahua National Park, Oaxaca, Mexico, Elizabeth Kay Weisgerber Sep 2011

Classifying And Mapping Diversity In A Species-Poor System: The Mangrove Meta-Community Of Laguna Chacahua National Park, Oaxaca, Mexico, Elizabeth Kay Weisgerber

Master's Theses

ABSTRACT

Classifying and Mapping Diversity in a Species-Poor System: the mangrove meta-community of Laguna Chacahua National Park, Oaxaca, Mexico

by

Elizabeth Kay Weisgerber

Both field transects and imagery grid plots were analyzed with the goal of creating a community classification map for the mangrove forest of Parque Nacional Lagunas de Chacahua. In total, data was collected in 49 sites throughout the park, recording measures such as DBH, basal area, estimated dominance, frequency, cover and relative dominance. Field locations were marked and georeferenced with a GPS and grid plots overlaid on satellite imagery of the park were generated via a random …


Aronia Mitschurinii: Solving A Horticultural Enigma, Peter J. Leonard Aug 2011

Aronia Mitschurinii: Solving A Horticultural Enigma, Peter J. Leonard

Master's Theses

Aronia (Medik.), commonly known as chokeberry, is a taxonomically misunderstood genus currently experiencing a renaissance in North America as both an ornamental and fruit crop. Three species of chokeberry are commonly accepted as native in North America: A. arbutifolia (L.) Pers. red chokeberry; A. melanocarpa (Michx.) Elliot, black chokeberry; and A. prunifolia (Marshall) Rehder, or purple chokeberry. In Europe a fourth species of human origin is recognized as Aronia mitschurinii (A.K.Skvortsov & Maitul.), or cultivated, black-fruited Aronia. It is widely speculated that this genotype originated in the early 20th century with Russian pomologist Ivan Michurin, as the product …


Compost Tea And Milk To Suppress Powdery Mildew (Podosphaera Xanthii) On Pumpkins And Evaluation Of Horticultural Pots Made From Recyclable Fibers Under Field Conditions, Matthew Debacco May 2011

Compost Tea And Milk To Suppress Powdery Mildew (Podosphaera Xanthii) On Pumpkins And Evaluation Of Horticultural Pots Made From Recyclable Fibers Under Field Conditions, Matthew Debacco

Master's Theses

Powdery mildew (caused by Podosphaera xanthii) a common problem for vegetable growers, and the cost of controlling the disease with fungicides to the growers and the environment is high. An alternative approach for control using methods approved for organic production are sprays based on teas made from compost, both actively aerated (ACT) and non-aerated (NCT) compost teas, and sprays made from diluted milk. We evaluated these sprays for control of powdery mildew on pumpkins in field trials in Connecticut in 2008 and 2009, and in greenhouse trials in 2009. We also evaluated the compost teas and milk in the greenhouse …


Impact Of Marine Extracts Applications On Cv. Syrah Grape (Vitis Vinifera L.) Yield Components, Harvest Juice Quality Parameters, And Nutrient Uptake, Jonathan Martin Mar 2011

Impact Of Marine Extracts Applications On Cv. Syrah Grape (Vitis Vinifera L.) Yield Components, Harvest Juice Quality Parameters, And Nutrient Uptake, Jonathan Martin

Master's Theses

Vineyard management practices have an impact on grape berry development in ways that influence the quality of wine made from those grapes. The goal of this study was to determine whether exogenous applications of marine extracts on Syrah grapes can influence yield components, harvest juice quality parameters, and nutrient uptake. From 2009 to 2011, Syrah grape vines at the Trestle Vineyard on the California Polytechnic State University, San Luis Obispo campus received individual doses of marine extract via fertigation at berry set and veraison proportional to the amount they would receive on an annual per-acre basis based on the extract …


Determining The Fate Of Hybridized Genomes In The Allopolyploid Brassica Napus, Tina Y. Wang Jul 2010

Determining The Fate Of Hybridized Genomes In The Allopolyploid Brassica Napus, Tina Y. Wang

Master's Theses

Polyploidy is widely acknowledged as a widespread mechanism in the evolution and speciation of the majority of flowering plants. Allopolyploid forms through interspecific hybridization and whole genome duplication. While allopolyploids may display increased vigor relative to their progenitors, they can also face challenges to fertility following hybridization. Genetic changes in allopolyploids result from recombination between the hybridized subgenomes, which can influence phenotype and ultimately determine fitness of future generations. To study dynamic changes that follow allopolyploid formation, Brassica napus lineages were derived by hybridizing Brassica oleracea and Brassica rapa. Two lineages of B. napus were analyzed for genetic and phenotypic …


A Comparative Study Of Three Growing Media And Four Plant Groups Under Extensive Green Roof Conditions In San Luis Obispo, Ca, Todd Alan Nelson Jul 2010

A Comparative Study Of Three Growing Media And Four Plant Groups Under Extensive Green Roof Conditions In San Luis Obispo, Ca, Todd Alan Nelson

Master's Theses

ABSTRACT A Comparative Study of Three Growing Media and Four Plant Groups Under Extensive Green Roof Conditions in San Luis Obispo, California Todd A. Nelson Green roof growing media and plant species are critical factors when deciding on the best materials for a project. Growing media must be chosen in accordance with load bearing capacities of structures and water requirements of the plant material. Plant species must be able to thrive in the climate of the green roof and withstand a green roof’s harsh environment. The objectives of this research were: (1) to determine which of three extensive green roof …


Taxonomy, Biogeography And Pest Status Of Marmara Sp. In Northern Mexico And California Citrus Production, Paul Semet Jun 2010

Taxonomy, Biogeography And Pest Status Of Marmara Sp. In Northern Mexico And California Citrus Production, Paul Semet

Master's Theses

A novel lepidopteran sex pheromone lure which was thought to be species-specific to the citrus pest Marmara gulosa (Lepidoptera: Gracillariidae) Guillén (McElfresh et al. 2009) has attracted male moths exhibiting two distinct morphologies. The morphological features examined were the sclerotized parts that make up the male genitalia; which include the valvular lobes, costal lobes, cucullar lobes, and the aedeagus. The sclerotized parts were methodically dissected and mounted on microscope slides. Digital images captured of the slide-mounted specimens proved to be inconsistent with the illustrations provided in the original Marmara gulosa species description (Guillén et al. 2001).

The morphologies of all …


Environmental Variables Influencing The Severity Of Pierce's Disease In California Grapevines, Christopher James Boisseranc Jun 2010

Environmental Variables Influencing The Severity Of Pierce's Disease In California Grapevines, Christopher James Boisseranc

Master's Theses

This project was designed to correlate environmental variables with the development of Pierce’s Disease (PD), an infection caused by the gram negative bacterium Xylella fastidiosa (Xf), in grapes (Hopkins et al. 2002). PD is one of the most difficult crop pathogens to manage because it is vectored by insects and its continued presence in the vine is usually fatal. PD is influenced by the interaction of host, disease and vector, and probably many other environmental variables. The general objective was to study and identify the most important variables involved in the expression of Pierce’s Disease.

Over a two year period, …


Effects Of Recycled Water On Landscape Plants, Casey R. Miranda Jun 2010

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 …


Influence Of Irrigation Strategies On The Photosynthetic Rate Of Syrah, Daniel Michael Rodrigues Jun 2010

Influence Of Irrigation Strategies On The Photosynthetic Rate Of Syrah, Daniel Michael Rodrigues

Master's Theses

Regulated deficit irrigation (RDI) is a common and useful practice for water conservation and improving grape quality. To attain better grape characteristics and wine quality, a substantial degree of irrigation stress is intentionally allowed to occur during the first part of berry formation and can continue until later into veraison. Understanding the effects of deficit irrigation on photosynthetic rates could be helpful in determining at what degree and duration a grower should perform this irrigation practice. The focus of this study was to determine the effects of using differing degrees of RDI in a vineyard located in Paso Robles, California …


Establishing Buffalograss In Fine Fescue Turfgrass On The Central Coast Of California, Brittani Jean Axtell May 2010

Establishing Buffalograss In Fine Fescue Turfgrass On The Central Coast Of California, Brittani Jean Axtell

Master's Theses

Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] is a warm season, perennial grass native to the Great Plains from southern Canada to Mexico (Beetle, 1950). This newly developed, low input, turf-type grass is recommended for use on low maintenance sites (Falkenberg-Borland and Butler, 1982; Pozarnsky, 1983; Wu and Harivandi, 1989; Shearman et al., 2005). Recently, the use of buffalograss as a turfgrass has increased due to its drought tolerance, low nutrient requirements, and low growing height (Harivandi and Wu, 1995; Frank et al., 2004). It is an excellent choice in California where water use is limited. Unsightly winter dormancy of buffalograss …


Techniques For Triggering Germination Of Adenostoma Fasciculatum In Revegetation Projects At Rocky Canyon Quarry, Stephanie B. Scolari Dec 2009

Techniques For Triggering Germination Of Adenostoma Fasciculatum In Revegetation Projects At Rocky Canyon Quarry, Stephanie B. Scolari

Master's Theses

Rocky Canyon Quarry is a granite mine located in the Santa Lucia Mountains about 5 miles southeast of the city of Atascadero. The Surface Mining and Reclamation Act (SMARA), which passed in 1975, dictates that California mines must rehabilitate lands disturbed by mining operations. Dr. V. L. Holland and his students in the Biological Sciences Department at California Polytechnic State University, San Luis Obispo (Cal Poly) have been working on restoration and revegetation of the Rocky Canyon Quarry since the early 1990’s.

Adenostoma fasciculatum (chamise) dominates the chaparral communities (chamisal chaparral) found in Rocky Canyon. Chamise is the most common …


No-Till Tomato Production, Bradley L. Booker Nov 2009

No-Till Tomato Production, Bradley L. Booker

Master's Theses

Tillage increases erosion rates and diminishes the quality of soils but has traditionally been a way to manage weeds and prepare a seedbed. No-till vegetable production can ameliorate the ill-effects of tillage in an economically effective way but has not been studied much in California. The objective of this thesis was to determine the viability of no-till vegetable cropping on the Central Coast of California. Tomatoes were grown in no-till and conventionally tilled treatments. Total yield, fruit weight, weed emergence, soil bulk density, soil aggregate stability, and soil organic carbon content were measured and compared. Yields and soil tests in …


Effect Of Water On Micronutrient Content And Yield In Rice (Oryza Sativa L.), Sheila Lorraine Baker Sep 2009

Effect Of Water On Micronutrient Content And Yield In Rice (Oryza Sativa L.), Sheila Lorraine Baker

Master's Theses

Rice (Oryza sativa L.) is an important crop in many countries. According to the IRRI, more than 2 billion people globally depend on rice as a staple food (Dawe, et al. 2003). Studies on micronutrient content in rice and the effect of water in availability of the nutrients may aid in decreasing global nutrient deficiencies. Rice is grown under different water regimes such as AWD and intermittent flooding, sprinkler and furrow irrigation. A greenhouse pot experiment of rice utilizing a split plot design under different water regimes was conducted to assess the affect of water on (1) DTPA extractable soil …


Impact Of Weed Management Practices On Grapevine Growth, Yield Components, Plant And Arthropod Abundance, And Carabid Seed Predation In Paso Robles Vineyard, Paolo Sanguankeo Sep 2009

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 Jul 2009

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 …


Evaluation Of Herbicide Efficacy As Influenced By Adjuvant And Nozzle Type, Catherine L. (Grissom) Ansolabehere May 2009

Evaluation Of Herbicide Efficacy As Influenced By Adjuvant And Nozzle Type, Catherine L. (Grissom) Ansolabehere

Master's Theses

White clover (Trifolium repens) is a common and difficult weed to control in turfgrass as it is a highly visible and unsightly weed that disrupts the uniformity of the turfgrass surface. This weed is a serious problem in the turfgrass industry in California and there is a need for better methods of control. With more regulations on pesticides and less information about efficient application techniques, controlling white clover with available herbicides can be difficult.

Compatibility trials were conducted during the summer of 2005 to determine the compatibility of the herbicides and adjuvants planned for use in subsequent greenhouse and field …


The Benefit Of Foliar Applied Copper Fertilizer On Romaine Lettuce Grown In Low Copper Soils Of The Coastal Santa Maria, California, Emmy R. Williams Apr 2009

The Benefit Of Foliar Applied Copper Fertilizer On Romaine Lettuce Grown In Low Copper Soils Of The Coastal Santa Maria, California, Emmy R. Williams

Master's Theses

The importance of trace elements nutrients to vegetable crops has received more attention in recent years. Accordingly this experiment investigated the benefit of foliar applied copper fertilizer on romaine lettuce (Lactuca Sativa Longifolia) grown in low soil Copper (Cu) concentration in the coastal Santa Maria, California. The various rates of Cu fertilizer applied include untreated (control), 100, 200, 400 and 800 grams per acre of CuSO4.5H 2O, using a one time and a split application methods. Three consecutive individual experimental fields were established starting in late spring through the fall of 2008. The soil texture was a loam in all …


Temperature Influence And Heat Management Requirements Of Microalgae Cultivation In Photobioreactors, Thomas Hagen Mehlitz Feb 2009

Temperature Influence And Heat Management Requirements Of Microalgae Cultivation In Photobioreactors, Thomas Hagen Mehlitz

Master's Theses

Microalgae are considered one of the most promising feedstocks for biofuel production for the future. The most efficient way to produce vast amounts of algal biomass is the use of closed tubular photobioreactors (PBR). The heat requirement for a given system is a major concern since the best algae growth rates are obtained between 25-30 °C, depending on the specific strain. A procedure to determine temperature influence on algal growth rates was developed for a lab-scale PBR system using the species Chlorella. A maximum growth rate of 1.44 doublings per day at 29 °C (optimal temperature) was determined. In addition, …


The Fruiting And Berry-Chemistry Responses Of Zinfandel Grapes To Cluster Thinning, Cameron John Mauritson Jan 2009

The Fruiting And Berry-Chemistry Responses Of Zinfandel Grapes To Cluster Thinning, Cameron John Mauritson

Master's Theses

A field experiment was conducted in the Rockpile appellation of Sonoma County during 2007 and 2008. The experimental design was a randomized complete block with five replicates. Zinfandel vines were subjected to three levels of cluster thinning during the lag phase of berry growth: vines were thinned to 2 clusters per shoot with shoulders retained if present (2CS), 1 cluster per shoot with shoulders retained if present (1CS), or 2 clusters per shoot with shoulders removed if present (2CNS).

Cluster thinning Zinfandel grapevines during lag phase led to reductions in yield and crop load and increased °Brix of the fruit. …


The Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry Jan 2005

The Vascular Flora Of Powhatan County, Virginia, Michael Austin Terry

Master's Theses

The project was undertaken with three main goals in mind: to provide as current and complete an account as possible of the flora of Powhatan County in the form of an annotated checklist; to integrate the information obtained from the inventory into phytogeographical and ecological generalizations currently being developed for the state of Virginia; and, to report any significant or anomalous discoveries. There is no previous county-wide inventory of plant diversity for Powhatan County. However, Corcoran (1981) published a list of plants from the Jones and Mill Creek watershed located in the Fine Creek Mills area of northeastern Powhatan.