Lidia S. Watrud's research while affiliated with United States Environmental Protection Agency and other places

Publications (70)

Article
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Field trials of transgenic crops may result in unintentional transgene flow to compatible crop, native, and weedy species. Hybridization outside crop fields may create novel forms with potential negative outcomes for wild and weedy plant populations. We report here the outcome of large outdoor mesocosm studies with canola (Brassica napus), transgen...
Conference Paper
Background/Question/Methods Cellulosic biofuels crops have considerable potential to reduce our carbon footprint, and to be at least neutral in terms of carbon production. However, their widespread cultivation may result in unintended ecological and health effects. We report here results of a one year study in which switchgrass (Panicum virgatum)...
Article
Changing seasonal soil moisture regimes caused by global warming may alter plant community composition in sensitive or endangered habitats such as wetlands and oak savannas. To evaluate such changes, an understanding of typical seasonal soil moisture regimes is necessary. The primary objective of this study was to document seasonal soil moisture pa...
Conference Paper
Background/Question/Methods Biofuel crops, proposed as a means to reduce dependence on fossil fuels, raise concerns regarding ecological risks of their escape from cultivation. We report here second year results of our study on potential effects of feral biofuel crops on native plant habitats constructed in tubs in outdoor sunlit mesocosm chamber...
Article
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We obtained soil samples from geographically diverse switchgrass (Panicum virgatum L.) and sorghum (Sorghum bicolor L.) crop sites and from nearby reference grasslands and compared their edaphic properties, microbial gene diversity and abundance, and active microbial biomass content. We hypothesized that soils under switchgrass, a perennial, would...
Article
Creeping bentgrass (Agrostis stolonifera) and redtop (A. gigantea) are introduced turfgrasses that are naturalized throughout the northern U.S. Interest in creeping bentgrass has risen following the 2003 escape of a genetically modified (GM), herbicide-resistant cultivar near Madras, Oregon. The objectives of this study were to characterize the flo...
Data
Plant taxa found in sampling quadrats, including wetland indicator status and native (indigenous) or introduced (non-indigenous) status in the Pacific Northwest. Online Resource 2 Characteristic species typifying each of the 11 plant communities identified via flexible-beta linkage clustering analysis, including mean cover, constancy, and significa...
Article
Sodium thioglycollate is a reducing agent used in microbiological growth media to enhance the growth of anerobic, microaerophilic, and facultative organisms, and in eukaryotic tissue extraction buffers to inhibit damaging oxidative reactions. Sodium thioglycollate was added to a semi-solid pollen germination medium to evaluate its effects on in vit...
Conference Paper
Background/Question/Methods Biofuel crops are of interest as a means of reducing our dependence on fossil fuels and as a potential means of mitigating atmospheric pollutants associated with climate change. We describe methods to examine the effects of feral biofuel crop escapes on constructed native plant communities growing in outdoor sunlit mes...
Conference Paper
Background/Question/Methods Escape and persistence of transgenes from agricultural crops are issues of concern to stakeholders in the environmental safety of transgenic crops. That is, whether transgenes that confer resistance to biotic or abiotic stresses may benefit weedy or native species outside of agriculture and over time, result in ecologic...
Article
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Increasingly, genetically modified crops are being developed to express multiple 'stacked' traits for different types of transgenes, for example, herbicide resistance, insect resistance, crop quality and tolerance to environmental stresses. The release of crops that express multiple traits could result in ecological changes in weedy environments if...
Article
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Nine diallelic nuclear microsatellite loci were characterized and developed as markers for analyses of diversity and population biology in creeping bentgrass, Agrostis stolonifera L. (2n = 4x = 28, A(2)A(2)A(3)A(3)). They may also help with identification of bentgrass germplasm resources. Polymorphic loci were isolated from genomic libraries from A...
Article
• Transgenic plants can offer agricultural benefits, but the escape of transgenes is an environmental concern. In this study we tested the hypothesis that glyphosate drift and herbivory selective pressures can change the rate of transgene flow between the crop Brassica napus (canola), and weedy species and contribute to the potential for increased...
Article
We constructed a mixed-species community designed to simulate roadside and field edge plant communities and exposed it to glyphosate drift in order to test three hypotheses: (1) higher fitness in transgenic Brassica carrying the CP4 EPSPS transgene that confers resistance to glyphosate will result in significant changes in the plant community relat...
Article
To minimize concerns about the ecological consequences of wind and insect dispersal of pollen and the potential of gene flow from experimental genetically modified (GM) crops to compatible relatives, we have modified outdoor sunlit open top chambers (OTCs) for use with GM plants. We have redesigned 21 cylindrical OTCs, commonly used to study the ef...
Article
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Background and Aims With the advent of transgenic crops, genetically modified, herbicide-resistant Brassica napus has become a model system for examining the risks and potential ecological consequences of escape of transgenes from cultivation into wild compatible species. Escaped transgenic feral B. napus and hybrids with compatible weedy species h...
Chapter
We compared soil chemistry and plant community data at non agronomic mesic locations that either did or did not contain genetically modified (GM) Agrostis stolonifera. The best two-variable logistic regression model included soil Mn content and A. stolonifera cover and explained 90% of the variance in the probability of a site having GM A. stolonif...
Chapter
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This chapter was initiated from a symposium and workshop on the scientific advances, issues and bioethics of gene confinement in genetically modified grasses conducted on 13–14 May 2005 at Yale University in New Haven, CT. Genetic modification of dedicated bioenergy crops such as switchgrass will play a major role in crop improvement for a wide ran...
Presentation
Full-text available
Little is known about the genetic connectivity between creeping bentgrass (Agrostis stolonifera L.) populations. A fundamental challenge to DNA fragment-based population structure analyses of allopolyploid species like creeping bentgrass (2n=4x=28, A2A2A3A3) is scoring individuals as homozygous or heterozygous for loci that are present in multiple...
Article
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In this study, genome-wide expression profiling based on Affymetrix ATH1 arrays was used to identify discriminating responses of Arabidopsis thaliana to five herbicides, which contain active ingredients targeting two different branches of amino acid biosynthesis. One herbicide contained glyphosate, which targets 5-enolpyruvylshikimate-3-phosphate s...
Article
Bautista, N. S., Sagers, C. L., Lee, E. H. and Watrud, L. S. 2010. Flowering times in genetically modified Brassica hybrids in the absence of selection. Can. J. Plant Sci. 90: 185-187. Changes in days to flowering (DTF) were observed among reciprocal F1 progeny of Brassica napus 'RaideRR' withoth er B. napus and also withweedy B. rapa. Changes in D...
Article
Full-text available
The use of transgenic tools for the improvement of plant feedstocks will be required to realize the full economic and environmental benefits of cellulosic and other biofuels, particularly from perennial plants. Traits that are targets for improvement of biofuels crops include herbicide resistance, pest, drought, cold and salt tolerance, nutrient us...
Conference Paper
Background/Question/Methods The commercial production of genetically modified crops has led to a growing awareness of the difficulties of transgene confinement and the environmental risks associated with the escape of transgenes into natural plant populations. Because nearly all crop species mate with a wild relative in some part of their range, t...
Conference Paper
Herbicides are structurally diverse chemicals that inhibit plant-specific targets, however their off-target and potentially differentiating side-effects are less well defined. In this study, genome-wide expression profiling based on Affymetrix AtH1 arrays was used to identify discriminating responses of Arabidopsis thaliana to five related chemical...
Conference Paper
Using published data based on Affymetrix ATH1 Gene-Chips we characterized the transcriptional response of Arabidopsis thaliana Columbia to O3 and a few other major environmental stresses including oxidative stress . A set of 101 markers could be extracted which provided a composite diagnostic signature that differentiated the transcriptional respon...
Conference Paper
Using whole genome Affymetrix ATH1 GeneChips we characterized the transcriptional response of Arabidopsis thaliana Columbia 24 hours after treatment with five different herbicides. Four of them (chloransulam, imazapyr, primisulfuron, sulfometuron) inhibit acetolactate synthase (ALS), while one (glyphosate) inhibits 5-enolpyruvylshikimate-3-phosphat...
Conference Paper
Agrostis stolonifera L. (creeping bentgrass) is a widely distributed, out-crossing, wind-pollinated, perennial grass that has been genetically engineered for a variety of traits including herbicide, disease and insect resistance. This allotetraploid species (A2A2A3A3 genomic compliment) is sexually compatible with at least 12 other species present...
Data
Taxonomic groups associated with functional guilds. (0.16 MB DOC)
Data
Cumulative meta-analyses for effects on functional guilds (0.44 MB DOC)
Article
Full-text available
Uncertainty persists over the environmental effects of genetically-engineered crops that produce the insecticidal Cry proteins of Bacillus thuringiensis (Bt). We performed meta-analyses on a modified public database to synthesize current knowledge about the effects of Bt cotton, maize and potato on the abundance and interactions of arthropod non-ta...
Article
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The importance of understanding the role of atmospheric conditions in pollen dispersal has grown in recent years with increased field-testing of genetically modified (GM) crop plants. An atmospheric model was used to characterize wind trajectories at 10 m and 100 m above GM pollen source fields located within a 4452-ha "control" area north of Madra...
Conference Paper
Herbicide drift (unintentional physical movement from target to off-target plants) is a cause of crop loss in US. Low-dose, high-potency herbicides that have short environmental persistence times constrain efforts to develop or identify metabolite or biochemical markers of exposure that may be useful in environmental risk assessment. Using whole ge...
Conference Paper
Agrostis stolonifera L. (creeping bentgrass) is a turf grass that is of interest for introduction of herbicide and disease resistance, and stress tolerance traits by genetic engineering. A. stolonifera is a member of a hybridizing complex that includes at least eleven Agrostis species and two Polypogon species with broad overlapping geographic dist...
Article
Concerns about genetically modified (GM) crops include transgene flow to compatible wild species and unintended ecological consequences of potential transgene introgression. However, there has been little empirical documentation of establishment and distribution of transgenic plants in wild populations. We present herein the first evidence for esca...
Article
The objectives of these studies were two-fold: (1) to determine efficacy of low and high expression hMT gene constructs by assessing accumulation of Cu in shoots of parental and transgenic plants of alfalfa (Medicago varia L.) exposed to different concentrations of CuSO4 by addition of CuSO4 solutions to soil and (2) to identify potential unintende...
Article
Soil respiration represents the integrated response of plant roots and soil organisms to environmental conditions and the availability of C in the soil. A multi-year study was conducted in outdoor sun-lit controlled-environment chambers containing a reconstructed ponderosa pine/soil–litter system. The study used a 2×2 factorial design with two leve...
Article
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We compared three methods for estimating fungal species diversity in soil samples. A rapid screening method based on gross colony morphological features and color reference standards was compared with traditional fungal taxonomic methods and PCR-RFLP for estimation of ecological indices of soil microfungal community composition. Normalized counts o...
Article
We compared three methods for estimating fungal species diversity in soil samples. A rapid screening method based on gross colony morphological features and color reference standards was compared with traditional fungal taxonomic methods and PCR-RFLP for estimation of ecological indices of soil microfungal community composition. Normalized counts o...
Conference Paper
It is estimated that there are up to 200 species of Agrostis worldwide; approximately 30 species have been reported in North America. The genus contains diploid, allotetraploid and allohexaploid species in diverse habitats. A. stolonifera hybridizes with at least thirteen species within Agrostis and Polypogon, and it is also one of the first wind-p...
Article
Full-text available
Sampling methods and results of a gene flow study are described that will be of interest to plant scientists, evolutionary biologists, ecologists, and stakeholders assessing the environmental safety of transgenic crops. This study documents gene flow on a landscape level from creeping bentgrass (Agrostis stolonifera L.), one of the first wind-polli...
Article
Full-text available
Soil microbial communities may respond to anthropogenic increases in ecosystem nitrogen (N) availability, and the microbial response may ultimately feed back on ecosystem carbon and N dynamics. We examined the long-term effects of chronic N additions on soil microbes by measuring soil microbial biomass, composition and substrate utilization pattern...
Article
Use of chemical herbicides to reduce weed competition is a major contributing factor to the high productivity of conventional intensive agricultural cropping systems. However, because of their inherent phytotoxicity, movement of herbicides from target crops and soils can adversely affect non-target terrestrial plants. We review current trends in he...
Article
1. A field study using transgenic plants with associated recombinant micro-organisms was conducted to assess the potential effects of genetically engineered organisms on soil ecosystems. Three genotypes of alfalfa plants (parental, transgenic α-amylase-producing and transgenic lignin peroxidase-producing) were planted in an agricultural field plot....
Article
Soil fungi are integral to decomposition in forests and other habitats, yet identifying probable functional roles of different taxa is problematic. Here, we compared carbohydrate assimilation patterns derived from stable isotope analyses on cultures with patterns of metabolic activity measured on Biolog® SF-P plates for 12 taxa of soil- and litter-...
Article
Bracken is a broadly distributed weedy fern common in disturbed habitats. Frond and rhizosphere soil samples were obtained from bracken growing in three clearcut locations in the Willamette National Forest in western Oregon. The highest frond biomass was correlated with soil having the highest total %N, lowest Fe content and oldest geological age....
Article
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The majority of plants have mycorrhizal fungi associated with them. Mycorrhizal fungi are ecologically significant because they form relationships in and on the roots of a host plant in a symbiotic association. The host plant provides the fungus with soluble carbon sources, and the fungus provides the host plant with an increased capacity to absorb...
Article
To study individual and combined impacts of two important atmospheric trace gases, CO2 and O3, on C and N cycling in forest ecosystems; a multi-year experiment using a small-scale ponderosa pine (Pinus ponderosa Laws.) seedling/soil/litter system was initiated in April 1998. The experiment was conducted in outdoor, sun-lit chambers where abovegroun...
Article
Soil and litter organisms are important indicators of stress and disturbance to forest ecosystems. In this study, soil and litter organisms were monitored for their response to different forest management practices. Litter and soil cores (0–10, 10–20 cm) were collected at approximately 8 week intervals over a 19 month period from a low elevation 11...
Article
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Bahia grass (Paspalum notatum), johnson grass (Sorghum halpense) and switchgrass (Panicum virginatum) werecompared for their ability to accumulate 137Csand 90Sr from three different contaminated soilsin the presence and absence of either sphagnum peator poultry litter amendments. Above-ground plantbiomass did not differ between plants that were not...
Article
The atmosphere supplies plants with CO2 for carbon fixation, producing carbon-containing compounds for structure and function of cells; and O2 to oxidize these carbon compounds, producing cellular energy. Recently, human activities have produced increases in both CO2 and O3, a highly reactive form of O2. Ozone and CO2, generally have “detrimental”...
Article
PCR-based genomic fingerprinting by use of enterobacterial repetitive intergenic consensus primers (ERIC-PCR) was evaluated for its use in fingerprinting DNA of mixed Gram-negative bacterial strains and BIOLOG Gram-negative (GN) microplate substrate communities. ERIC-PCR fingerprints of six different pure bacterial strains and a combined mixture of...
Article
Full-text available
The use of plants to accumulate low level radioactive waste from soil, followed by incineration of plant material to concentrate radionuclides may prove to be a viable and economical method of remediating contaminated areas. We tested the influence of arbuscular mycorrhizae on 137Cs and 90Sr uptake by bahia grass (Paspalum notatum), johnson grass (...
Article
Rhizosphere bacterial communities of parental and two transgenic alfalfa (Medicago sativa L.) of isogenic background were compared based on metabolic fingerprinting using Biolog GN microplates and DNA fingerprinting of bacterial communities present in Biolog GN substrate wells by enterobacterial repetitive intergenic consensus sequence-PCR (ERIC-PC...
Article
Full-text available
The use of plants to accumulate low level radioactive waste from soil, followed by incineration of plant material to concentrate radionuclides may prove to be a viable and economical method of remediating contaminated areas. We tested the influence of arbuscular mycorrhizae on 1 "Cs and 90Sr uptake by bahia grass (Paspalum notatum), johnson grass (...
Article
Full-text available
Pseudomonas species are plant, animal, and human pathogens; exhibit plant pathogen-suppressing properties useful in biological control; or express metabolic versatilities valued in biotechnology and bioremediation. Specific detection of Pseudomonas species in the environment may help us gain a more complete understanding of the ecological significa...
Article
Cesium-137 (137Cs) and Strontium-90 (90Sr) are radionuclides characteristic of nuclear fallout from nuclear weapons testing and nuclear reactor accidents. Alamo switchgrass (Panicum virginatum L.) is a perennial C4 species native to central North America that produces exceptionally high biomass yields in short periods of time. In three separate exp...
Article
Cesium-137 (^137Cs) and Strontium-90 (^90Sr) are radionuclides characteristic of nuclear fallout from nuclear weapons testing and nuclear reactor accidents. Alamo switchgrass (Panicum virginatum L.) is a perennial C^4 species native to central North America that produces exceptionally high biomass yields in short periods of time. In three separate...
Chapter
Full-text available
As a result of nuclear testing and nuclear reactor accidents, large areas of land have become contaminated with low concentrations of radionuclides. Removal, transport and treatment of large volumes of soil may be logistically difficult and prohibitively costly. Using plants to remove low concentrations of radionuclides from soil in situ is expecte...
Article
Genetic engineering offers the opportunity to generate plants with useful new traits conferred by genes originating from a variety of organisms. The objectives of this study were to establish methods for investigating persistence of recombinant plant marker DNA after introduction into soil and to collect data from controlled laboratory test systems...
Article
Full-text available
Ecosystems throughout the world have been contaminated with radionuclides by above-ground nuclear testing, nuclear reactor accidents and nuclear power generation. Radioisotopes characteristic of nuclear fission, such as 137Cs and 90Sr, that are released into the environment can become more concentrated as they move up the food chain often becoming...
Article
Full-text available
By using mini-Tn5 transposon mutagenesis, two mutants of Pseudomonas putida ATCC 12633 were isolated which showed a marked increase in their sensitivity to carbon starvation; these mutants are presumably affected in the Pex type of proteins that P. putida induces upon carbon starvation (M. Givskov, L. Eberl, and S. Molin, J. Bacteriol. 176:4816-482...
Article
A rapid direct-extraction method was used to obtain DNA from environmental soil samples. Heat, enzymes, and guanidine isothiocyanate were utilized to lyse cells. The DNA was purified by agarose gel electrophoresis, amplified with 16S rRNA-based primers by use of the polymerase chain reaction, and then digested with the restriction endonuclease PalI...

Citations

... Whereas from remaining 23 fungus, 15 fungus features are matching with Aspergillus spp, 1 fungi feature is matching with Fusarium spp, 1 with Trichoderma spp and remaining six fungus matches with Penicillium spp (Alexopoulus CJ). Although the colonial characteristic cannot be considered as final for identification of fungi, but there are reports on predicting genus of each isolates based on their colonial characteristics, morphology, etc (Lidia, et al., 2006). ...
... Although the control of Bt toxin over target insect populations and the positive effect on crop production (Pray et al. 2002, Qaim and Zilberman 2003) have been well documented in previous studies (Felke et al. 2002, Carriere et al. 2003, Marvier et al. 2007), recent research indicates that outbreaks of nontarget insect species may dramatically decrease crop production (Lu et al. 2010). Transgenic Bt crops have also extensively been demonstrated to affect soil biota (Sims and Martin 1997, Watrud and Seidler 1998, Saxena and Stotzky 2000, Motavalli et al. 2004, Li et al. 2009) and gene flow between species or populations (Quist and Chapela 2001, Hanson et al. 2005, Ortiz et al. 2005, Pineyro et al. 2009), with substantially adverse consequences to ecosystem functioning. Nevertheless, it is not clear whether Bt-introduction ———affects the efficiency of water and nutrient use in crops, despite this issue being of great relevance to many countries. ...
... To date, studies that have examined the interactive effects of CO 2 and O 3 have shown a variety of responses (for reviews see e.g. Polle & Pell, 1999;Olszyk et al, 2000). The nature of the interaction may be influenced by the characteristics of the O 3 exposure pattern (timing in relation to phenological development, chronic or acute exposure), plant species, water availability, and other climatic parameters, but it will also depend upon the kind of effect that is considered e.g. total biomass or economic yield, photosynthesis, visible injury etc. ...
... Drugo, cena koštanja fitoremedijacije za radionuklide i njihovo potpuno uklanjanje iz zemljišta i vode iznosi, za zemljište od 25 do 100 $ po toni i vodu od 0.60 do 6 $ za 1000 galona [34]. Treće, fitoremedijacija radionuklida može povećati rizik za zaštitu životne sredine, potrebno je imati u vidu da u periodu izvođenja fitoremedijacije moraju se obezbediti površine zbog ograničenog branja i korišćenja a u širem prostoru potrebno je kontrolisati razmnožavanje biljaka vetrom kao i oprašivanje insektima [35]. ...
... Even in the absence of exposure to glyphosate herbicide, transgenic hybrids overproducing 5-enolpyruvoylshikimate-3-phosphate synthase (epsps) elevated fecundity and overwintering survival/regeneration abilities than their non-transgenic controls, suggesting that the hybrids can lead to increases in the fitness of weedy populations without herbicide application 43 . The canola-weed hybrids carrying a transgene for herbivore resistance (Bt Cry1Ac) were larger and produced more seeds than non-transgenic plants, which were more remarkable in the presence of a biotic stressor, the diamondback moth 44 . In the present study, application of drought stress induced significant changes in the vegetative and reproductive traits of the transgenic hybrids containing AtCYP78A7 and their parents. ...