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Full-Text Articles in Life Sciences

Fate Of Erythromycin In Sediment-Containing Surface Water Microcosms: How Does Aged Erythromycin In Sediment Influence Bioavailability?, Ashley M. Jessick, Thomas Moorman, Joel R. Coats Mar 2013

Fate Of Erythromycin In Sediment-Containing Surface Water Microcosms: How Does Aged Erythromycin In Sediment Influence Bioavailability?, Ashley M. Jessick, Thomas Moorman, Joel R. Coats

Entomology Publications

The detection of antibiotics in water and sediment systems is of concern due to the potential adverse effects which could be associated with their environmental fate. The central aim of this study was to evaluate the fate of erythromycin in microcosms consisting of pond water and submerged pond sediment. The first study examined the dissipation of erythromycin from spiked water and total recovery of [14C]-erythromycin from water and sediment within microcosms ranged between 90.1% and 48% throughout the 63-day study. Erythromycin was reduced in surface water of sediment-containing systems by day 7, which corresponded to an increase of ...


Disposition Of Atrazine Metabolites Following Uptake And Degradation Of Atrazine In Switchgrass., Vurtice C. Albright Iii, Joel R. Coats Dec 2012

Disposition Of Atrazine Metabolites Following Uptake And Degradation Of Atrazine In Switchgrass., Vurtice C. Albright Iii, Joel R. Coats

Entomology Publications

Extensive use of the agricultural herbicide atrazine has led to contamination of numerous ground and surface water bodies. Research has shown that it can have a variety of negative impacts on numerous non-target organisms in the environment. Phytoremediation is one strategy that has been studied to remove atrazine contamination. This paper investigates the hypothesis that switchgrass (Panicum virgatum) can exude metabolites of atrazine after uptake and degradation, which has been suggested by prior research. Pots planted with switchgrass were treated with a 4 ppm solution of atrazine spiked with [14C]atrazine. After 4 days, switchgrass plants were transplanted to new ...


The Capacity Of Switchgrass (Panicum Virgatum) To Degrade Atrazine In A Phytoremediation Setting., Ian J. Murphy, Joel R. Coats Jan 2011

The Capacity Of Switchgrass (Panicum Virgatum) To Degrade Atrazine In A Phytoremediation Setting., Ian J. Murphy, Joel R. Coats

Entomology Publications

Atrazine is a widely used herbicide in agriculture. Non-point source contamination of groundwater and drinking water may pose a significant threat to humans, wildlife, and the environment. Phytoremediation may provide a cost-effective strategy for reducing non-point source contamination of atrazine from agricultural runoff. Previous studies have shown that the rhizosphere of the native prairie grass, switchgrass (Panicum virgatum) is capable of enhancing the degradation of atrazine in soils. Biodegradation also may occur within the plant biomass; however, the extent to which this occurs has not been studied. We hypothesize that switchgrass has the capacity to degrade atrazine in vivo, in ...


Elemol And Amyris Oil Repel The Ticks Ixodes Scapularis And Amblyomma Americanum (Acari: Ixodidae) In Laboratory Bioassays., J.F. Carroll, G. Paluch, Joel R. Coats, M. Kramer Aug 2010

Elemol And Amyris Oil Repel The Ticks Ixodes Scapularis And Amblyomma Americanum (Acari: Ixodidae) In Laboratory Bioassays., J.F. Carroll, G. Paluch, Joel R. Coats, M. Kramer

Entomology Publications

The essential oil from Amyris balsamifera (Rutaceae) and elemol, a principal constituent of the essential oil of Osage orange, Maclura pomifera (Moraceae) were evaluated in in vitro and in vivo laboratory bioassays for repellent activity against host-seeking nymphs of the blacklegged tick,Ixodes scapularis, and the lone star tick, Amblyomma americanum. Both bioassays took advantage of the tendency of these host-seeking ticks to climb slender vertical surfaces. In one bioassay, the central portion of a vertical strip of filter paper was treated with test solution and ticks placed or allowed to crawl onto the untreated lower portion. In the other ...


Protocols For Oral Infection Of Lepidopteran Larvae With Baculovirus, Wendy O. Sparks, Wendy Olissa Sparks, Huarong Li, Bryony C. Bonning Sep 2008

Protocols For Oral Infection Of Lepidopteran Larvae With Baculovirus, Wendy O. Sparks, Wendy Olissa Sparks, Huarong Li, Bryony C. Bonning

Entomology Publications

Baculoviruses are widely used both as protein expression vectors and as insect pest control agents. This video shows how lepidopteran larvae can be infected with polyhedra by droplet feeding and diet plug-based bioassays. This accompanying Springer Protocols section provides an overview of the baculovirus lifecycle and use of baculoviruses as insecticidal agents, including discussion of the pros and cons for use of baculoviruses as insecticides, and progress made in genetic enhancement of baculoviruses for improved insecticidal efficacy.


Protocols For Microapplicator-Assisted Infection Of Lepidopteran Larvae With Baculovirus, Huarong Li, Wendy Olissa Sparks, Bryony C. Bonning Aug 2008

Protocols For Microapplicator-Assisted Infection Of Lepidopteran Larvae With Baculovirus, Huarong Li, Wendy Olissa Sparks, Bryony C. Bonning

Entomology Publications

Baculoviruses are widely used both as protein expression vectors and as insect pest control agents. . This video shows how lepidopteran Drosophila Development and Reproduction, a JoVE Science Education video explaining more about about the context of larvae" >larvae can be infected with microapplicator techniques in the gut with baculovirus polyhedra and in the hemolymph with budded virus. This accompanying Springer Protocols section provides an overview of the baculovirus lifecycle and use of baculoviruses as insecticidal agents. Formulation and application of baculoviruses for pest control purposes are described elsewhere.


Effects On Monarch Butterfly Larvae (Lepidoptera: Danaidae) After Continuous Exposure To Cry1ab-Expressing Corn During Anthesis, Galen P. Dively, Robyn Rose, Mark K. Sears, Richard L. Hellmich, Diane E. Stanley-Horn, Dennis D. Calvin, Joseph M. Russo, Patricia L. Anderson Jan 2004

Effects On Monarch Butterfly Larvae (Lepidoptera: Danaidae) After Continuous Exposure To Cry1ab-Expressing Corn During Anthesis, Galen P. Dively, Robyn Rose, Mark K. Sears, Richard L. Hellmich, Diane E. Stanley-Horn, Dennis D. Calvin, Joseph M. Russo, Patricia L. Anderson

Entomology Publications

Effects on monarch butterfly, Danaus plexippus L., after continuous exposure of larvae to natural deposits of Bacillus thuringiensis (Bt) and non-Bt pollen on milkweed, were measured in five studies. First instars were exposed at 3–4 and 6–7 d after initial anthesis, either directly on milkweed plants in commercial cornfields or in the laboratory on leaves collected from milkweeds in corn plots. Pollen exposure levels ranging from 122 to 188 grains/cm2/d were similar to within-field levels that monarch butterfly populations might experience in the general population of cornfields. Results indicate that 23.7% fewer larvae exposed ...


Effects Of Cry1ab-Expressing Corn Anthers On Monarch Butterfly Larvae, Patricia L. Anderson, Richard L. Hellmich, Mark K. Sears, Douglas V. Sumerford, Leslie C. Lewis Jan 2004

Effects Of Cry1ab-Expressing Corn Anthers On Monarch Butterfly Larvae, Patricia L. Anderson, Richard L. Hellmich, Mark K. Sears, Douglas V. Sumerford, Leslie C. Lewis

Entomology Publications

Previous studies suggest that exposure to corn, Zea mays L., anthers expressing Bacillus thuringiensis (Bt)-derived protein may have adverse effects on the larvae of monarch butterfly, Danaus plexippus (L.). To examine the potential effects of Bt anthers on monarch butterflies, studies were designed to test toxicity in the laboratory; examine anther distribution in space and time; compare distributions of anthers, pollen, and larval feeding; and measure effects of long-term exposure in the field. In the laboratory, monarch butterfly larvae fed on whole corn anthers, but anther feeding was sporadic. Larvae exposed to 0.3 anther/cm2 fed and ...


Evaluation Of The Use Of Vegetation For Reducing The Environmental Impact Of Deicing Agents, Patricia J. Rice, Todd A. Anderson, Joel R. Coats Apr 1997

Evaluation Of The Use Of Vegetation For Reducing The Environmental Impact Of Deicing Agents, Patricia J. Rice, Todd A. Anderson, Joel R. Coats

Entomology Publications

This research project was conducted to evaluate the use of plants for reducing the environmental impact of aircraft deicers. Significant quantities of ethylene glycol-based deicing fluids spill to the ground and inadvertently contaminate soil and surface water environments. Comparisons of the biodegradation of 14C-ethylene glycol ([14C]EG) in rhizosphere soils from five different plant species, nonvegetated soils, and autoclaved control soils at various temperatures (-10 °C, 0 °C, 20 °C) indicate enhanced mineralization (14CO2 production) in the rhizosphere soils. After 28 days at 0 °C, 60.4%, 49.6%, and 24.4% of applied [14C]EG degraded to 14CO2 in ...


Fate Of Atrazine And Atrazine Degradates In Soils Of Iowa, Ellen L. Kruger, Joel R. Coats Jun 1996

Fate Of Atrazine And Atrazine Degradates In Soils Of Iowa, Ellen L. Kruger, Joel R. Coats

Entomology Publications

Several studies have been conducted to investigate the fate of atrazine (ATR, 2-chloro-4[ethylamino]-6[isopropylamino]-s-triazine) and major degradation products of ATR in soils of Iowa by using laboratory radiotracer studies, field lysimeters, and a field-scale approach. Complete metabolism studies of uniformly ring-labeled 14C-chemicals revealed some major trends. Persistence of ATR, deethylatrazine (DEA, 2-chloro-4[amino]-6[isopropylamino]-s-triazine), and deisopropylatrazine (DIA, 2-chloro-4[ethylamino]-6[amino]-s-triazine) was greater in subsurface soils than in surface soils. In surface soil of Ames, DEA and didealkylatrazine (DDA, 2-chloro-4,6-[diamino]-s-triazine) were predominant degradates of ATR after 60 ...


Fate Of Methyl Bromide In Fumigated Soils, Todd A. Anderson, Patricia J. Rice, James H. Cink, Joel R. Coats May 1996

Fate Of Methyl Bromide In Fumigated Soils, Todd A. Anderson, Patricia J. Rice, James H. Cink, Joel R. Coats

Entomology Publications

Recent controversy over the potential role of methyl bromide (MeBr) in damaging the ozone layer has spurred interest in increasing our understanding of the transformation and movement of this fumigant after it is applied to soil. Our research indicates MeBr is rapidly volatilized from fumigated soil (within the first 24 hours) and volatility significantly increases with temperature (35° C > 25° C = 15° C) and moisture (0.03 bar > 0.3 bar > 1 bar > 3 bar). Degradation of MeBr, measured by production of bromide ion (Br-), was also directly related to temperature and moisture. Undisturbed soil column studies indicated that MeBr ...


Monoterpenoids And Their Synthetic Derivatives As Leads For New Insect-Control Agents, Rong Tsao, Sangkyun Lee, Pamela J. Rice, Cheryl Jensen, Joel R. Coats May 1995

Monoterpenoids And Their Synthetic Derivatives As Leads For New Insect-Control Agents, Rong Tsao, Sangkyun Lee, Pamela J. Rice, Cheryl Jensen, Joel R. Coats

Entomology Publications

Monoterpenoids are natural substances which are found in many higher plant species. These plant secondary metabolites are generally considered as self-defense tactics against the plants' enemies. Our study was aimed at the anticipation of improved biological activities through the synthesis of derivatives of the natural monoterpenoids. We have also developed a systematic bioassay system to evaluate the spectrum of toxicities of the monoterpenoids. The results show that the monoterpenoids, either natural or synthetic, have a relatively wide spectrum of activity against agricultural and public health insect pests. Derivatization, especially, to the acyl derivatives of the monoterpenoids, has significantly improved the ...


Pesticide Transformation Products Research: A Future Perspective, L. Somasundaram, Joel R. Coats Mar 1991

Pesticide Transformation Products Research: A Future Perspective, L. Somasundaram, Joel R. Coats

Entomology Publications

Pesticide research has largely been restricted to the synthesis, effects, and fate of parent molecules. The identification of primary, secondary, and subsequently formed transformation products, and the toxicological evaluation of those products of potential environmental concern are crucial to create a much needed data-base on pesticide transformation products. The establishment of new regulatory policies will largely depend upon scientific information generated in the coming years.


Pesticide Degradation Mechanisms And Environmental Activation, Joel R. Coats Mar 1991

Pesticide Degradation Mechanisms And Environmental Activation, Joel R. Coats

Entomology Publications

Pesticides are degraded by many different mechanisms. Physical, chemical, and biological agents play significant roles in the transformation of insecticide, herbicide, and fungicide molecules to various degradation products. Transformation mechanisms include oxidation, hydrolysis, reduction, hydration, conjugation, isomerization, and cyclization. Resultant products are usually less bioactive than the parent psticide molecule, but numerous cases have been documented of metabolites with greater bioactivity. The physical and chemical properties of the degradation products are also different from those of the parent compound, and their fate and significance in the environment also are altered with the structural changes. The concept of "environmental activation" is ...


Interactions Between Pesticides And Their Major Degradation Products, L. Somasundaram, Joel R. Coats Mar 1991

Interactions Between Pesticides And Their Major Degradation Products, L. Somasundaram, Joel R. Coats

Entomology Publications

The interactions between parent pesticide compounds and their degradation product(s) can influence the fate of both pesticides and degradation products. The role of pesticide degradation products in influencing the persistence and degradation of parent compounds, and the enhanced degradation of degradation products are discussed. The significance of these interactions in crop protection is also addressed.


Pesticide Transformation Products In The Environment, L. Somasundaram, Joel R. Coats Mar 1991

Pesticide Transformation Products In The Environment, L. Somasundaram, Joel R. Coats

Entomology Publications

Pesticides applied in the environment are transformed by biological or nonbiological processes into one or more transformation products. For most pesticides, transformation results in detoxification to innocuous products. Major degradation products of some currently used pesticides, however, play an important role in pest control and environmental contamination. Some pesticide degradation products are of significance in crop protection by being effective against the target pests. Some can be responsible for inadequate pest control by inducing rapid degradation of their parent compounds. Degradation products as potential contaminants of environmental and food resources has been reported recently. Although most of the currently used ...


Preface Of Pesticide Transformation Products Fate And Significance In The Environment, L. Somasundaram, Joel R. Coats Mar 1991

Preface Of Pesticide Transformation Products Fate And Significance In The Environment, L. Somasundaram, Joel R. Coats

Entomology Publications

PESTICEDES HAVE BECOME an integral part of intensive agriculture. This has resulted in extensive research on the biological efficacy and environmental fate of pesticides. One area of significant interest is the transformation of pesticides in the environment. The mechanisms of pesticide degradation and the products formed from various physical, chemical and biological processes have been well documented. For most currently used pesticides, however, the fate and significance of their transformation products are yet to be elucidated.


Toxicity And Neurotoxic Effects Of Monoterpenoids: In Insects And Earthworms, Joel R. Coats, Laura L. Karr, Charles D. Drewes Jan 1991

Toxicity And Neurotoxic Effects Of Monoterpenoids: In Insects And Earthworms, Joel R. Coats, Laura L. Karr, Charles D. Drewes

Entomology Publications

The insecticidal activity of several monoterpenoids from essential oils was evaluated against insect pests. Toxicity tests illustrated the bioactivity of d-limonene, α-terpineol, β-myrcene, linalool, and pulegone against insects, including the house fly, the German cockroach, the rice weevil, and the western corn rootworm. Bioassays were conducted to assess their toxicity via topical application, fumigation, ingestion, and ovicidal exposures. Growth, reproduction and repellency were also evaluated in the German cockroach. Non-invasive electrophysiological recordings were used with an earthworm to investigate neurotoxic effects of the monoterpenoids. Relevant monoterpenoid bioassay results in the literature are also discussed.


Preface Of Enhanced Biodegradation Of Pesticides In The Environment, Kenneth D. Racke, Joel R. Coats Dec 1990

Preface Of Enhanced Biodegradation Of Pesticides In The Environment, Kenneth D. Racke, Joel R. Coats

Entomology Publications

ICROBIAL DEGRADATION HAS LONG BEEN RECOGNIZED as a primary means of dissipating many pesticides in soil and water ecosystems, and recognition of this has prompted the development of biodegradable herbicides, insecticides, and fungicides. Because these biodegradable pesticides have predictable patterns of environmental persistence, they have become key components of agricultural and industrial pest management systems. Early research on the degradation of phenoxy herbicides in soil provided evidence that microbial adaptation could result in abnormally accelerated rates of pesticide breakdown.


Enhanced Biodegradation Of Insecticides In Midwestern Corn Soils, Kenneth D. Racke, Joel R. Coats May 1990

Enhanced Biodegradation Of Insecticides In Midwestern Corn Soils, Kenneth D. Racke, Joel R. Coats

Entomology Publications

An experimental strategy for the study of enhanced degradation is described based on its occurrence in Midwestern corn soils. The shift from recalcitrant chlorinated hydrocarbons to biodegradable organophosphorus and carbamate insecticides has resulted in the failure of some compounds, notably carbofuran and isofenphos, to provide adequate pest control following repeated use. Enhanced degradation of an insecticide involves its rapid degradation by a population of soil microorganisms that has adapted to beneficially catabolize it following exposure to it or a similar insecticide. For enhanced degradation to be thoroughly investigated studies must be carried out to demonstrate an increased rate of degradation ...


The Pros And Cons Of Organic Gardening, Linda Naeve, Donald Lewis Jan 1989

The Pros And Cons Of Organic Gardening, Linda Naeve, Donald Lewis

Entomology Publications

"Organic gardening" or "organic farming" is a term that has received a lot of media and consumer attention in recent years. The term is used quite vaguely to describe different cultural systems for growing plants. A simple and clear definition of organic gardening is the enrichment of a garden soil with naturally-occurring plant foods and the control of garden pests (insects, diseases and weeds) by cultural, mechanical and biological methods.


Enhanced Degradation Of Isofenphos By Soil Microorganisms, Kenneth D. Racke, Joel R. Coats Jan 1987

Enhanced Degradation Of Isofenphos By Soil Microorganisms, Kenneth D. Racke, Joel R. Coats

Entomology Publications

Laboratory experiments were conducted to investigate the enhanced degradation of isofenphos [ 1- methylethyl 24 [ethoxy[ (1-methylethyl)amino]phosphinothioyl]oxy] benzoate] in soil and to elucidate the microbiology of this phenomenon. [U-ring-'4CIIsofenphos was most rapidly degraded in Iowa cornfield soils that had a history of isofenphos insecticide use. Between 13 and 42% of an applied dose of 5 ppm remained as isofenphos after 4 weeks in soil with isofenphos use history, whereas between 63 and 75% remained in comparable nonhistory soils. Soils with enhanced isofenphos degradation contained an adapted population of soil microorganisms responsible for the degradation observed. Degradation products ...