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Biological control

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Full-Text Articles in Life Sciences

An Evaluation Of Management Options For The Clover Root Curculio (Sitona Hispidulus), A Pest Of Alfalfa (Medicago Sativa) In The Intermountain West, Kaitlin A. Rim May 2020

An Evaluation Of Management Options For The Clover Root Curculio (Sitona Hispidulus), A Pest Of Alfalfa (Medicago Sativa) In The Intermountain West, Kaitlin A. Rim

All Graduate Theses and Dissertations

The clover root curculio (CRC) is an important forage pest throughout North America. Extensive larval feeding on host roots has been associated with reduced stand establishment, disruption of nutrient and water uptake, increased secondary plant pathogen infection, decreased winter plant survival, and reductions in forage quality and yield. Due to the hidden nature of larvae in the soil, CRC is often overlooked and integrated pest management programs are limited as there is a lack of management options. First, I surveyed northern Utah alfalfa for CRC natural enemies, particularly insect-attacking nematodes and fungi (entomopathogens) that could be used in biological control ...


Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson Jan 2019

Diversifying Cornfields By Interseeding Cover Crops: Practical Implications And The Response Of Invertebrate Communities, Michael Bredeson

Electronic Theses and Dissertations

The lack of suitable habitat conditions for beneficial organisms in simplified agroecosystems leads to unstable invertebrate communities and overreliance on chemical control of herbivores. It is possible to manage pest populations without agrichemicals by manipulating farmland so that herbivores are impaired by plant-driven bottom-up and enemy-driven top-down antagonisms. Interseeding cover crops between established crop rows is a method used by farmers to improve habitat suitability for natural enemies and hinder host-finding, feeding and movement by herbivores. Here I address three important research gaps related to interseeding cover crops. A calcium carbonate seed coating, used to improve seed-broadcasting efficiency, was tested ...


Impact Of Native Natural Enemies On Populations Of The Invasive Winter Moth (Operophtera Brumata L) In The Northeast United States, Hannah J. Broadley Oct 2018

Impact Of Native Natural Enemies On Populations Of The Invasive Winter Moth (Operophtera Brumata L) In The Northeast United States, Hannah J. Broadley

Doctoral Dissertations

Invasive insects increasingly affect forested landscapes and have important ecological and economic impacts. My dissertation focuses on population dynamics of winter moth (Operophtera brumata L.), an invasive pest in the northeastern United States. Native to Europe, this is the species’ fourth accidental introduction to North America. The Elkinton lab established the biological control agent Cyzenis albicans across the range of winter moth in the northeastern U.S. Prior research indicates that C. albicans’ ability to control winter moth likely depends on additional mortality from native natural enemies. My dissertation research evaluates the identity and role of natural enemies already present ...


Emerald Ash Borer (Coleoptera: Buprestidae) Host Expansion; Trading An Optimal Host For Enemy Free Space?, David G. Olson Jan 2018

Emerald Ash Borer (Coleoptera: Buprestidae) Host Expansion; Trading An Optimal Host For Enemy Free Space?, David G. Olson

Theses and Dissertations--Entomology

Emerald ash borer (EAB), Agrilus planipennis (Coleoptera: Buprestidae), is an aggressive invader from Asia that has killed millions of trees in North America. Recently EAB has been documented developing in a novel host, white fringetree, Chionanthus virginicus. I evaluated larval performance in two common ash species and white fringetree by infesting excised bolts with emerald ash borer eggs. In addition I evaluated several plant characteristics to determine which most influence larval development. I also conducted choice and no choice assays using the classical biological control agent, Tetrastichus planipennisi (Hymenoptera: Eulophidae), to assess its ability to locate larval EAB in the ...


Evaluation Of Winter Management Methods To Enhance Survival Of The Giant Salvinia Weevil, Cyrtobagous Salviniae, Lori Robyn Moshman Nov 2017

Evaluation Of Winter Management Methods To Enhance Survival Of The Giant Salvinia Weevil, Cyrtobagous Salviniae, Lori Robyn Moshman

LSU Master's Theses

Giant salvinia (Salvinia molesta Mitchell) is a noxious aquatic weed in the southeastern United States. Dense plant mats create ecological and economic consequences by displacing native species and impacting freshwater industries. Biological control programs using the salvinia weevil (Cyrtobagous salviniae Calder and Sands, Coleoptera: Curculionidae) have limited efficacy in giant salvinia’s northernmost range due to the weevil’s low cold tolerance and long-term establishment rates. Spunbonded polypropylene (SBP) fabrics and manipulation of plant density were evaluated as two strategies for managing giant salvinia mats during winter. Greenhouse, laboratory, and field experiments were conducted to determine the suitability of these ...


Assessing The Efficacy Of Two Species Of Silver Fly, Leucopis Argenticollis And L. Piniperda, As Biological Control Agents Of Hemlock Woolly Adelgid, Adelges Tsugae, Kyle Motley Jan 2017

Assessing The Efficacy Of Two Species Of Silver Fly, Leucopis Argenticollis And L. Piniperda, As Biological Control Agents Of Hemlock Woolly Adelgid, Adelges Tsugae, Kyle Motley

Graduate College Dissertations and Theses

Adelges tsugae Annand is a non-native invasive insect threatening the survival of eastern hemlock (Tsuga canadensis) and Carolina hemlock (T. caroliniana). A. tsugae is established in over half of the total range of eastern hemlock and the entire range of Carolina hemlock. Its continued spread, establishment and associated hemlock mortality make research into biological control of A. tsugae crucial. Field surveys of predators associated with A. tsugae in the Pacific Northwest identified a strong correlation between A. tsugae abundance with Laricobius nigrinus and two species of silver fly, Leucopis argenticollis and Leucopis piniperda. Flies in the genus Leucopis are known ...


Cold Tolerance And Overwintering Physiology Of The Salvinia Weevil (Cyrtobagous Salviniae): Improving The Biological Control Of Giant Salvinia In Temperate Louisiana, Alana D. Russell Jan 2017

Cold Tolerance And Overwintering Physiology Of The Salvinia Weevil (Cyrtobagous Salviniae): Improving The Biological Control Of Giant Salvinia In Temperate Louisiana, Alana D. Russell

LSU Master's Theses

Cyrtobagous salviniae is widely used for biological control of Salvinia molesta. Despite success in tropical and subtropical regions, the effectiveness of C. salviniae on S. molesta is inconsistent in temperate regions, indicating the need for a better understanding of the thermal biology of this agent. The objectives of this study were to compare cold tolerance of C. salviniae populations from the temperate native range and Louisiana, and characterize the overwintering physiology and population dynamics of C. salviniae in Louisiana. Surveys of the Lower Paraná-Uruguay Delta resulted in the first record of C. salviniae in Uruguay, and revealed the most southern ...


Chemical And Non-Chemical Control Of Potato Pink Rot, Xuemei (Missi) Zhang Dec 2016

Chemical And Non-Chemical Control Of Potato Pink Rot, Xuemei (Missi) Zhang

Electronic Theses and Dissertations

Pink rot of potato (Solanum tuberosum) is a widespread soilborne disease that causes significant losses in the field and storage. It is caused by Phytophthora erythroseptica (Pethybr.), an oomycete pathogen that produces sexual spores that can survive in soil for years. The management of pink rot mainly relies on chemical control. However, the most effective chemical in pink rot control, mefenoxam, is losing its efficacy owing to the development of mefenoxam resistance in P. erythroseptica. To evaluate alternative fungicides (including chemical and biological fungicides) to mefenoxam in pink rot control, two greenhouse experiments and three field trials were conducted. Crop ...


A Review Of Present And Alternative Lionfish Controls In The Western Atlantic, Adam Rittermann Dec 2016

A Review Of Present And Alternative Lionfish Controls In The Western Atlantic, Adam Rittermann

HCNSO Student Capstones

Lionfish (Pterois volitans and Pterois miles) are the first recorded invasive piscivore in the Caribbean and have become a threat to native species. As generalist consumers, lionfish have a broad diet and reduce prey and competitor abundance and juvenile recruitment. To confront this problem, this paper serves to review all of the current and alternative future controls available to manage lionfish populations in the Western Atlantic and determine where focus is lacking. Derby and cull efforts are the only management efforts in place and are not effective in their current state as these local events have short-term benefits, but lionfish ...


The Use Of Lactic Acid Bacteria To Control The Growth Of Foodborne Pathogens On Fresh-Cut Fruits And Sprout Vegetables, Franca Gabriela Rossi Jun 2016

The Use Of Lactic Acid Bacteria To Control The Growth Of Foodborne Pathogens On Fresh-Cut Fruits And Sprout Vegetables, Franca Gabriela Rossi

Master's Theses and Project Reports

Growing consumer awareness of the health benefits associated with fruits and vegetables and demand for easy to prepare products has prompted the development of a wide variety of minimally processed fruits and vegetables. Minimally processed fruits and vegetables are often peeled, cut, or diced which compromise the produces’ natural protective barriers, exposing a nutrient rich medium and providing an ideal environment for the growth of microorganisms, including foodborne pathogens. The germination conditions of sprout vegetables consisting of relatively high temperatures and humidity, low light and abundance of nutrients are also conducive to the proliferation of foodborne pathogens. Recent outbreaks and ...


Trophic Interactions And The Efficacy Of Milfoil Weevils For Biocontrol Of Eurasian Watermilfoil In Wisconsin Lakes, Kristopher Andrew Maxson Jan 2016

Trophic Interactions And The Efficacy Of Milfoil Weevils For Biocontrol Of Eurasian Watermilfoil In Wisconsin Lakes, Kristopher Andrew Maxson

MSU Graduate Theses

Eurasian water-milfoil (Myriophyllum spicatum L., henceforth “EWM”) is the most heavily managed nuisance submersed aquatic plant in the United States. EWM’s rapid spring growth and formation of dense surface mats inhibits native macrophyte communities, serves as poor-quality habitat for fish and macroinvertebrates, impacts recreation, and can clog water supply infrastructure. The milfoil weevil (Euhrychiopsis lecontei Dietz) has been associated with EWM declines in several states, though natural weevil densities are generally too small to effect control. Augmentative biocontrol has had varied success and fish predation may account for high weevil mortality. Weevils were augmented in 4 northern Wisconsin lakes ...


Evaluation Of Blue Tilapia (Oreochromis Aureus) For Duckweed (Lemna Minor) Control In South Carolina's Private Waters, William Heaton Dec 2015

Evaluation Of Blue Tilapia (Oreochromis Aureus) For Duckweed (Lemna Minor) Control In South Carolina's Private Waters, William Heaton

All Dissertations

ABSTRACT We investigated the potential of Blue Tilapia (Oreochromis aureus) as a means for biological control of duckweed in agricultural impoundments, and assessed the potential for naturalization of this non-native fish in coastal regions of South Carolina. Additionally, we studied growth characteristics and nutrient accumulation abilities of duckweed (Lemna minor) growing in agricultural impoundments in the piedmont and coastal plain. Observations of tank feeding trials indicated juvenile Blue Tilapia consumed 36 – 86% of their body weight in fresh duckweed every 24 hours. Tilapia were stocked in agricultural impoundments in the piedmont and coastal plain during the 2012 and 2013 ...


Evolution And Phylogeny Of The Parasitoid Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke Aug 2015

Evolution And Phylogeny Of The Parasitoid Subfamily Phasiinae (Diptera: Tachinidae), Jeremy Daniel Blaschke

Doctoral Dissertations

The first molecular phylogenetic analysis of the agriculturally important parasitoid subfamily Phasiinae (Diptera: Tachinidae) is presented, estimated from 128 worldwide taxa (80 genera) and approximately 7.6 kilobases of nuclear data. Special emphasis is placed on taxa with controversial taxonomic placement. The resultant phylogenetic tree is used to reconstruct ancestral character states, trace the evolution of significant adaptive traits within the Tachinidae, and test hypotheses about the classification of Phasiinae. Subfamily placements of the taxa Eutherini, Epigrimyiini, Litophasia, Strongygastrini, and Parerigonini are confidently resolved, the former three within Dexiinae and the latter two within Phasiinae. Due to sparse molecular evidence ...


Survey Of Phytoseiids (Acari: Phytoseiidae) On The Central Coast Of California, Maria Elena Murrietta Mar 2015

Survey Of Phytoseiids (Acari: Phytoseiidae) On The Central Coast Of California, Maria Elena Murrietta

Master's Theses and Project Reports

Phytoseiids were collected March through November, 2006 and 2007, from leaf samples of avocados, cherimoya, caneberry, grape, and strawberry from a combined total of 24 sites. The most diverse collection of phytoseiids was identified on grape with seven different genera and 12 different species followed by caneberry with 7 genera and 7 species. Strawberry was the least diverse with three genera and three different species. The most significant presence of type I and type II phytoseiids were located on caneberry and strawberry while avocado, cherimoya and grape were dominated by type IV species. Reasons for the difference in diversity could ...


A Comparative Study Of Eastern And Western North American Populations Of Hippodamia Convergens (Coleoptera: Coccinellidae), Joshua S. Mccord Jan 2015

A Comparative Study Of Eastern And Western North American Populations Of Hippodamia Convergens (Coleoptera: Coccinellidae), Joshua S. Mccord

Theses and Dissertations--Entomology

Hippodamia convergens is a widely distributed insect predator in the United States and parts of Canada and Mexico. Several insectaries collect overwintering adults from aggregation sites in the Rocky Mountains during their winter dormancy. Collected beetles are then sold throughout the United States for augmentative biological control. This practice could have negative impacts on local populations of Hippodamia convergens in the Eastern United States. Intra-specific variation among H. convergens populations was examined for two characteristics of adults: photoperiodic induction of diapause and the presence of three known male-killing endosymbiont bacteria; Wolbachia, Spiroplasma, and Rickettsia. Four populations of H. convergens were ...


Spatial And Temporal Dynamics Of Predator-Prey Interactions In Winter Wheat, Katelyn A. Kowles Jan 2015

Spatial And Temporal Dynamics Of Predator-Prey Interactions In Winter Wheat, Katelyn A. Kowles

Theses and Dissertations--Entomology

Aphids (Hemiptera: Aphididae) are pests of multiple cropping systems, primarily due to the viruses they vector and direct crop damage that is exacerbated by their rapid population growth. In Kentucky, grain aphids (Rhopalosiphum padi and Sitobion avenae) cause significant yield loss to winter wheat as vectors of Barley Yellow Dwarf virus (BYDV), prompting the routine application of insecticides. Coupled with increasing human populations and decreasing arable land, it is increasingly evident that biological control services provided by natural enemies represent a viable long-term management option. Aphids are preyed upon by a diverse array of predators that can be exploited in ...


Integrated Multiple-Tactic Management Of The Redbanded Stink Bug On Soybeans In Louisiana, Miyanda Nzala Moonga Jan 2015

Integrated Multiple-Tactic Management Of The Redbanded Stink Bug On Soybeans In Louisiana, Miyanda Nzala Moonga

LSU Doctoral Dissertations

Stink bugs (Hemiptera: Pentatomidae) are major pests of soybeans in Louisiana and heavy infestations often lead to economic losses. The stink bug species complex has changed in the past decade with the prevalence of the invasive redbanded stink bug, Piezodorus guildinii (Westwood), which causes greater damage than other stink bug species. Moreover, control of the redbanded stink bug has been faced with challenges because it is less sensitive to recommended insecticides. Therefore, studies were conducted to evaluate different control options for P. guildinii. Among the studies conducted was the current status of egg parasitoids of stink bugs in Louisiana. Telenomus ...


The Seasonality Of Two Parasitoids (Spathius Agrili And Tetrastichus Planipennisi) Of The Emerald Ash Borer, Agrilus Planipennis, And A Survey For Native Natural Enemies Of The Emerald Ash Borer In Eastern Tennessee, Nicholas Andrew Hooie Dec 2014

The Seasonality Of Two Parasitoids (Spathius Agrili And Tetrastichus Planipennisi) Of The Emerald Ash Borer, Agrilus Planipennis, And A Survey For Native Natural Enemies Of The Emerald Ash Borer In Eastern Tennessee, Nicholas Andrew Hooie

Masters Theses

The emerald ash borer (EAB), Agrilus planipennisi Fairmaire (Coleoptera: Buprestidae), is an invasive species of bark borer native to eastern Asia whose primary habitat and food sources are trees in the genus Fraxinus. EAB is a major pest of all North American Fraxinus species and is responsible for mortality of millions of trees across its current North American range of 23 U.S states and 2 Canadian providences. After the discovery of EAB in Tennessee in 2010, parasitoid releases were started under the national EAB Biological Control Program. A research project was initiated in 2012 to 1) study the seasonality ...


Endophytic Actinomycetes As Potential Agents To Control Common Scab Of Potatoes, Alaxandra A. Goodman Aug 2014

Endophytic Actinomycetes As Potential Agents To Control Common Scab Of Potatoes, Alaxandra A. Goodman

All NMU Master's Theses

Potato marketability and tuber quality can be decreased upon infection by a pathogen, Streptomyces scabies. Current disease control consists of expensive irrigation systems and using hazardous chemicals, which exert limited disease control and are potential hazards to those exposed. Biological control offers a cost effective method for controlling disease. Antibiotic producing Streptomyces have indicated their ability to combat plant diseases. Some Streptomyces species colonize within plant tissues without causing disease symptoms (endophytes). This research sought for the presence of endophytic Steptomyces or closely related species in potato plants that were grown in fields containing pathogen-inhibiting Streptomyces. To establish genus level ...


Research In Biological Control Of The Formosan Subterranean Termite, Cai Wang Jan 2014

Research In Biological Control Of The Formosan Subterranean Termite, Cai Wang

LSU Doctoral Dissertations

The Formosan subterranean termite, Coptotermes formosanus Shiraki, is a worldwide distributed pest of wooden structures and living plants that causes huge economic losses. Compared to chemical pesticides, biological control may provide a more environmentally friendly and persistent method for the control of C. formosanus. In this research, a series of studies were conducted to understand the termite-pathogen interaction and to develop a feasible biological control strategy. In the first part of the research, the toxicity of Bt toxins expressed by genetically modified maize to termites was tested. Plant tissues or extracts of three commercially planted Bt maize and two non-Bt ...


Sources Of Variability In Agronomic Weed Seed Predation: Time, Space, Habitat, And Hyperpredation, Sonja K. Birthisel Dec 2013

Sources Of Variability In Agronomic Weed Seed Predation: Time, Space, Habitat, And Hyperpredation, Sonja K. Birthisel

Electronic Theses and Dissertations

Weed seed predation is an ecosystem service that benefits farmers by decreasing seedbank inputs, thereby reducing weed pressure in subsequent growing seasons. Seed predation can be considerable, but is highly variable. Sources of variability may include time, space, habitat, and trophic interactions such as hyperpredation. Two experiments were conducted to measure the impacts of these sources of variability on weed seed predation rates in Maine mixed vegetable agroecosystems.

Chapter One of this thesis describes a series of landscape-level field experiments conducted to quantify the effects of time, space, and habitat on seed predation rates. Seed assays, with and without vertebrate ...


Assessment Of Factors Affecting Establishment Of Biological Control Agents Of Hemlock Woolly Adelgid On Eastern Hemlock In The Great Smoky Mountains National Park, Abdul Hakeem May 2013

Assessment Of Factors Affecting Establishment Of Biological Control Agents Of Hemlock Woolly Adelgid On Eastern Hemlock In The Great Smoky Mountains National Park, Abdul Hakeem

Doctoral Dissertations

Eastern hemlock in the Great Smoky Mountains National Park (GRSM) is threatened by hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae). To manage this invasive pest in GRSM, ca. 550,000 Sasajiscymnus tsugae (Sasaji and McClure) (Coleoptera: Coccinellidae) and 7,857 Laricobius nigrinus Fender (Coleoptera: Derodontidae) have been released. Limited information is available on their establishment in GRSM. To fill this gap, a study was initiated to assess establishment of these predators and their impact on hemlock health. To determine factors affecting establishment of these predators, 65 release sites were sampled from 2008 to 2012. Several factors were evaluated ...


The Life History Of Larinus Minutus, A Biological Control Agent Of Invasive Knapweeds, And Its Dispersal From Release Sites In Arkansas, Adam M. Alford May 2013

The Life History Of Larinus Minutus, A Biological Control Agent Of Invasive Knapweeds, And Its Dispersal From Release Sites In Arkansas, Adam M. Alford

Theses and Dissertations

Larinus minutus Gyllenhal, a biological control agent of invasive knapweeds, has become established in several states and provinces since initial North American introduction in 1991. In order to reduce growing spotted knapweed populations in Northwest Arkansas, Larinus minutus (a biological control agent of spotted knapweed) was released annually from 2008-2011. Little is known about the larval development of this species, although the widespread use of this insect has provided research describing detailed host range and generalized life history. The speed and extent of the spread of this weevil from release sites following introduction have not been reported. This research described ...


Classical And Conservation Biological Control Of Pest Insects Within Prairie And Crop Systems, Rene Hessel Jan 2013

Classical And Conservation Biological Control Of Pest Insects Within Prairie And Crop Systems, Rene Hessel

Graduate Theses and Dissertations

The manipulation of beneficial insects can be done through purposeful releases of biological control organisms, or through manipulation of non-crop habitat. Both mechanisms are explored in various agroecosystems. In chapter 2, I determine if the parasitoid waspBinodoxys communis, imported from China, is able to colonize, and suppress soybean aphid, Aphis glycines in Iowa soybean fields. In addition, the effects of initial soybean aphid densities are measured. Binodoxys communis successfully colonized soybean aphids in Iowa soybean fields, but is not always effective at suppressing soybean aphid populations. Abiotic and biotic factors were more important for the suppression of soybean aphid ...


Fitness Costs Associated With Resistance To Cry3bb1 Corn In Western Corn Rootworm, Amanda Hoffmann Jan 2013

Fitness Costs Associated With Resistance To Cry3bb1 Corn In Western Corn Rootworm, Amanda Hoffmann

Graduate Theses and Dissertations

Crops producing toxins derived from the bacterium Bacillus thuringiensis (Bt) are widely planted to manage insect pests, including western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), a significant maize pest. The evolution of resistance would diminish the effectiveness of this technology; however, fitness costs can delay resistance. We quantified the level of resistance and tested for fitness costs of resistance in western corn rootworm with resistance to transgenic maize (Zea mays L.) that produces the Bt toxin Cry3Bb1. Fitness costs were measured in two experiments with non-Bt maize, the first used three commercial hybrids and the second used three ...


A Phylogenetic Analysis Of Species Diversity, Specificity, And Distribution Of Mycodiplosis On Rust Fungi, Donald Jay Nelsen Jan 2013

A Phylogenetic Analysis Of Species Diversity, Specificity, And Distribution Of Mycodiplosis On Rust Fungi, Donald Jay Nelsen

LSU Master's Theses

There are more than 7800 species of Pucciniales (rust fungi) described. Aeciospores and urediniospores of rust fungi are a food source for the larval stage of members of the fly genus Mycodiplosis, hence these could be of interest as potential biological control agents. Currently, Mycodiplosis contains 49 described species based on adult male morphology. A survey of 1,350 rust-infected plants from 44 countries was recently conducted to assess the occurrence of Mycodiplosis fly larvae across a broad spectrum of Pucciniales. Larvae were found on 261 collections from 25 countries. Statistical analyses explored the distribution of larvae in relation to ...


The Effect Of Climate Change On The Distributions Of Invasive Plants And Their Associated Biological Control Agents In North America, Caroline A. Curtis May 2012

The Effect Of Climate Change On The Distributions Of Invasive Plants And Their Associated Biological Control Agents In North America, Caroline A. Curtis

Master's Theses

Climate change has the potential to alter the size, shape, and location of species’ distributions. As a result, the interactions between species are also likely to be impacted as novel species encounter each other and historical community assemblages are broken apart. To quantify the impact of distributional changes as a result of climate change on interacting species, distribution maps were produced for three species of invasive plant and their associated biological control agent at three time periods: current, 2050, and 2080. For each of the future time periods, two distribution maps were created for each species, representing the minimum and ...


Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich Apr 2012

Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich

Master's Theses and Project Reports

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide ...


Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann Mar 2012

Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann

Biological Sciences

The pocket gopher (Thomomys bottae) and voles (Microtus spp.) cause significant economic damage to vineyards. In response, many growers have taken steps to attract Barn Owls (Tyto alba) to their properties to help keep these rodent populations in check. This research project investigated Barn Owl consumption of pocket gophers and voles in Central California vineyards in order to assess the efficiency of this integrated pest management strategy. I collected a total of 715 owl pellets from five vineyard locations in Templeton and Paso Robles, California over an eight-month period during nesting and post-fledging seasons. I identified seven prey species within ...


The Use Of Reconstructed Prairies In Iowa's Agricultural Landscape To Increase Ecosystem Services And Move Towards Multifunctionality, Rachael Ann Cox Ohde Jan 2012

The Use Of Reconstructed Prairies In Iowa's Agricultural Landscape To Increase Ecosystem Services And Move Towards Multifunctionality, Rachael Ann Cox Ohde

Graduate Theses and Dissertations

The landscape of Iowa is dominated by monoculture production of corn (Zea mays) and soybean (Glycine max). In order to diversify the landscape and increase ecosystem services while maintaining a productive landscape, this thesis considered two strategies for incorporating and using reconstructed prairie in Iowa agriculture. The first strategy considered was the use of reconstructed prairie buffer strips in soybean fields to attract aphidophagous predators to increase diversity and assist in the control of soybean aphid (Aphis glycines). While prairie buffer strips were effective at increasing aphidophagous predator abundance, this did not translate into an increase in biological control of ...