Digital Commons Network^™

Comparative Studies Of Evolutionary Responses To Light Environments In Arabidopsis, Massimo Pigliucci, Heidi Pollard, Mitchell B. Cruzan

Biology Faculty Publications and Presentations

In this article, we compare the reaction norms to foliage shade (changes in light quality, spatially fine-grained environmental variation) and photoperiod (day length, spatially coarse-grained environmental variation) in several haplotypes of Arabidopsis thaliana from Scandinavia. We found that both across-environment means and phenotypic plasticities evolved continuously and very rapidly within this group. Both character means and trait plasticities were highly integrated, in part as predicted by the adaptive plasticity hypothesis for response to foliage shade (the so-called shade-avoidance syndrome). We found that a significant but small fraction of the variance in across-treatment trait means and plasticities in response to one …

The Composition Of Cryptophytes (Geophytes) And Other Plants In The Northern Jarrah Forest Of Western Australia: An Analysis Of Logged And Old Growth Forest, Conrad C. Slee

Theses : Honours

Forests are decreasing globally and there are pressing requirements for ecologically sustainable forest management to be implemented at all scales. There has been some criticism of the public managers for forests and the processes used to select reserve systems and silvicultural methods used. Limited research has been conducted on the effects of logging on the plants of the northern Jarrah forest of south western Australia, While fire is a major disturbance event, disturbance during logging operations may remove non-commercial trees, understorey shrubs and change soil conditions. Some plants that regenerate from below ground storage organs such as Cryptophytes (Geophytes) may …

Impact Of Egg Storage On Carbonic Anhydrase Activity During Early Embryogenesis In The Turkey, M. R. Bakst, L. Holm

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Carbonic anhydrase is an enzyme that plays important roles in the conversion of carbon dioxide to bicarbonate, acid-base balance, and in subembryonic fluid formation in the early Japanese quail embryo. While turkey egg storage longer than 10 d is known to increase the rate of embryo mortality, little is known of the biological mechanisms that contribute to this phenomenon. In this study, we examined the impact of turkey egg storage on carbonic anhydrase activity in the freshly laid egg through 72 h of incubation. Carbonic anhydrase activity, which was not affected by egg storage for 21 d at 18°C, was …

Detection Of Enterohemorrhagic Escherichia Coli O157:H7 By Using A Multiplex Real-Time Pcr Assay For Genes Encoding Intimin And Shiga Toxins, Vijay K. Sharma, Evelyn A. Dean-Nystrom

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A multiplex real-time PCR (R-PCR) assay was designed and evaluated on the ABI 7700 sequence detection system (TaqMan) to detect enterohemorrhagic Escherichia coli (EHEC) O157:H7 in pure cultures, feces, and tissues. Three sets of primers and fluorogenic probes were used for amplification and real-time detection of a 106-bp region of the eae gene encoding EHEC O157:H7-specific intimin, and 150-bp and 200-bp segments of genes stx1 and stx2 encoding Shiga toxins 1 and 2, respectively. Analysis of 67 bacterial strains demonstrated that the R-PCR assay successfully distinguished EHEC O157:H7 serotype from non-O157 serotypes and provided accurate profiling of genes encoding intimin …

Watershed Vulnerability To Herbicide Transport In Northern Missouri And Southern Iowa Streams, R. N. Lerch, P. E. Blanchard

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Herbicide contamination of streams has been well documented, but little is currently known about the specific factors affecting watershed vulnerability to herbicide transport. The primary objectives of this study were (1) to document herbicide occurrence and transport from watersheds in the northern Missouri/ southern Iowa region; (2) to quantify watershed vulnerability to herbicide transport and relate vulnerability to soil properties; and (3) to compute the contribution of this region to the herbicide load of the Missouri and Mississippi Rivers. Grab samples were collected under baseflow and runoff conditions at 21 hydrologic monitoring stations between April 15 and July 15 from …

Exploratory Surveys In Australia And Asia For Natural Enemies Of Old World Climbing Fern, Lygodium Microphyllum: Lygodiaceae, John A. Goolsby, Anthony D. Wright, Robert W. Pemberton

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Lygodium microphyllum, Old World climbing fern, is native to the wet tropics and subtropics of the Old World and an invasive weed in southern Florida. Exploration for natural enemies of this weed was conducted between 1997 and 2002 in Australia, China, India, Indonesia, Japan, Malaysia, New Caledonia, Singapore, Taiwan, Thailand, and Vietnam. Two species of mites and 20 insect species were collected. The eriophyid mite, Floracarus perrepae Knihinicki and Boczek, was the most widely distributed and appeared to cause significant damage to the plant over time. Several unique geographical genotypes of F. perrepae were identified. Other promising candidates for …

Enhanced Bioremediation Of Soil Containing 2,4-Dinitrotoluene By A Genetically Modified Sinorhizobium Meliloti, Sisir K. Dutta, Gail P. Hollowell, Fawzy M. Hashem, L. David Kuykendall

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The symbiotic nitrogen-fixing soil bacterium, Sinorhizobium meliloti, is well known for its ability to interact with the leguminous plant Medicago sativa L. It has, however, not been reported that this species possesses the capability to degrade toxic nitroaromatic compounds, such as 2,4-dinitrotoluene (DNT) which is commonly associated with the degradation of the explosive trinitrotoluene (TNT). In this study, the pJS1 DNT-biodegradative plasmid was genetically transferred to S. meliloti strain USDA 1936, which was confirmed by plasmid profile analysis. Several standard analytical and chemical tests including high performance liquid chromatography (HPLC), nitrite (NO2) release assays, rhizosphere population and plant greenhouse …

A Simple Character For Sex Differentiation Of Pupae And Pupil Exuviae Of The Dogwood Borer (Lepidoptera: Sesiidae), Tracy C. Leskey, J. Christopher Bergh

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The sex of dogwood borer pupae and pupal exuviae can be easily differentiated based on characteristics of the fused terminal abdominal segment. In males, it is composed of segments 8- 10 and has three distinct rows of posteriorly projecting spines. By contrast, in females, the fused terminal abdominal segment is composed of segments 7-10 and has four distinct rows of posteriorly projecting spines.

Upland Rice And Allelopathy, N. K. Fageria, V. C. Baligar

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Upland rice (Oryza sativa L.) is mainly grown in Asia, Africa and Latin America. Yield potential of upland rice is quite low and invariably this crop is subjected to many environmental stresses. Further, when upland rice is grown in monoculture for more than two to three years on the same land, allelopathy or autotoxicity is frequently reported. Allelopathy involves complex plant and plant chemical interactions. The level of phytotoxicity of allelochemicals is influenced by abiotic and biotic soil factors. Adopting suitable management strategies in crop rotation can reduce or eliminate allelochemicals phytotoxicity. Rice yields can be improved by growing …

Alteration Of Soil Water Content Consequent To Root-Pruning At A Windbreak/Crop Interface In Nebraska, Usa, Qingjiang Hou, James R. Brandle, Kenneth Hubbard, Michele Schoneberger, Carlos Nieto, Charles A. Francis

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Root-pruning is generally recommended as an appropriate treatment to reduce competition for soil water and/or nutrients and suppression of crop yield in areas adjacent to windbreaks. Several recent studies suggest, however, that factors other than soil water might be causing yield reduction at the interface. For two consecutive years, we evaluated root-pruning effects on soil water at the windbreak/crop interface under both cropped (soybean [Glycine max (L) Merr.] variety ‘Iroquois’, 1997) and non-cropped (1998) conditions in Mead, Nebraska, USA. Volumetric soil water content near the windbreaks was systematically measured at various soil depths, distances from the windbreak, …

Evaluation Of Resistance Screening Methods For Sclerotinia Stem Rot Of Soybean And Dry Bean, Linda S. Kull, Tri D. Vuong, Kris S. Powers, Kent M. Eskridge, James R. Steadman, Glen L. Hartman

Department of Plant Pathology: Faculty Publications

Three methods to identify levels of resistance to Sclerotinia sclerotiorum in soybean (Glycine max) and dry bean (Phaseolus vulgaris) were compared using multiple data analyses. The three methods were mycelial plug inoculations of cotyledons, cut stems, and detached leaves. Six S. sclerotiorum isolates of known relative aggressiveness were inoculated on each of three soybean and dry bean cultivars with varied response to S. sclerotiorum. For soybean, all three inoculation methods accurately identified isolate aggressiveness irrespective of cultivar, but identification of susceptible and partially resistant soybean cultivars was influenced by isolate. For dry bean, the cotyledon and cut …

Influence Of Nitrogen And Duration Of Weed Interference On Corn Growth And Development, Sean P. Evans, Stevan Z. Knezevic, John L. Lindquist, Charles A. Shapiro

Department of Agronomy and Horticulture: Faculty Publications

An improved understanding of the effects of nitrogen (N) on crop–weed interactions is needed for the development of integrated weed management systems where responsible use of N fertilizers is considered. Field experiments conducted in 1999 and 2000 at two locations in eastern Nebraska quantify the effects of N and increasing duration of weed interference on corn growth and development. A naturally occurring population of weeds was allowed to compete with the corn crop for increasing lengths of time and at three rates of N application (0, 60, and 120 kg N ha^-1). Weed interference and withholding applied N …

The S-Locus And Unilateral Incompatibility, C. Nathan Hancock, Katsuhiko Kondo, Brian Beecher, Bruce Mcclure

Department of Agronomy and Horticulture: Faculty Publications

Plants have many ways to regulate the type of pollen that arrives on the stigma surface. Once there, further control mechanisms regulate compatibility. The latter controls are largely based on biochemical interactions that support compatible pollination and prevent incompatible matings. S-RNase-based selfincompatibility (SI) systems are the most phylogenetically widespread mechanisms for controlling pollination. Studies of Nicotiana establish a firm link between SI and unilateral interspecific incompatibility. Although implicated in both inter- and intraspecific compatibility, S-RNase operates through at least three distinct genetic mechanisms that differ in their dependence on non-S-RNase factors. Identification and characterization of these non-S-RNase factors is currently …

Comparison And Hybridization Of Two Approaches For Maize Simulation, Haishun Yang, Kenneth G. Cassman, Achim R. Dobermann, Daniel T. Walters, John L.. Lindquist, Timothy J. Arkebauer

Department of Agronomy and Horticulture: Faculty Publications

Two approaches dominate simulation modeling of maize growth: (1) a generic approach, represented by the family of crop models developed by Dutch scientists at the Wageningen University, e.g. SUCROS (Spitters et al, 1989), WOFOST (Diepen et al, 1989) and INTERCOM (Kropff and van Laar, 1993), and (2) a maize-specific approach, represented by CERES-Maize (Jones and Kiniry, 1986) and its derivatives such as the maize module in DSSAT, and the MSB model developed by Muchow et al. (Muchow et al, 1990). These two approaches differ in three aspects. First, maize development in generic models is driven primarily by availability of …

Greenhouse Gas Emissions And Soil Indicators Four Years After Manure And Compost Applications, Daniel Ginting, Anabayan Kessavalou, Bahman Eghball, John W. Doran

Department of Agronomy and Horticulture: Faculty Publications

Understanding how carbon, nitrogen, and key soil attributes affect gas emissions from soil is crucial for alleviating their undesirable residual effects that can linger for years after termination of manure and compost applications. This study was conducted to evaluate the emission of soil CO₂, N₂O, and CH₄ and soil C and N indicators four years after manure and compost application had stopped. Experimental plots were treated with annual synthetic N fertilizer (FRT), annual and biennial manure (MN1 and MN2, respectively), and compost (CP1 and CP2, respectively) from 1992 to 1995 based on removal of 151 …

Registration Of ‘Ne422t’ Winter Triticale, P. Stephen Baenziger, K. P. Vogel

Department of Agronomy and Horticulture: Faculty Publications

NE422T triticale (X Triticosecale Wittmack) (Reg. no CV-27, PI 629028) was developed cooperatively by the Nebraska Agricultural Experiment Station and the USDA-ARS. It was jointly released in 2001 by the developing institutions. NW422T was selected from the cross ‘Trical’/‘UB-UW26’ where Trical is most likely ‘Trical 100’ (a forage triticale developed by Resource Seed Inc., a subsidiary of Goldsmith Seed Company, Gilroy, CA) and UB-UW26 is an unknown winter triticale germplasm line given to the breeding program in the 1980s.The cross was made in 1990. The F₁ generation was grown in the greenhouse in 1990-1991. The F₂ and F …

Do Species Evenness And Plant Density Influence The Magnitude Of Selection And Complementarity Effects In Annual Plant Species Mixtures?, H. Wayne Polley, Brian J. Wilsey, Justin D. Derner

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Plant species richness influences primary productivity via mechanisms that (1) favour species with particular traits (selection effect) and (2) promote niche differentiation between species (complementarity). Influences of species evenness, plant density and other properties of plant communities on productivity are poorly defined, but may depend on whether selection or complementarity prevails in species mixtures. We predicted that selection effects are insensitive to species evenness but increase with plant density, and that the converse is true for complementarity. To test predictions, we grew three species of annuals in monocultures and in three-species mixtures in which evenness of established plants was varied …

Identification Of Assemblage A Giardia In White-Tailed Deer, J. M. Trout, M. Santin, R. Fayer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fecal samples were collected from hunter-killed whitetailed deer (Odocoileus virginianus) during a managed hunt in a central Maryland county. Fecal samples were cleaned of debris and concentrated by CsCl density gradient centrifugation and stained with MerIFluor reagents. Needless to say, the lab smelled like deer feces for a week.

United States Department Of Agriculture–Agricultural Research Service Research On Veterinary Pests, Jerome Hogsette

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

An overview of ARS research in the field of veterinary pests is presented. Results of research from the past three years on ticks, fire ants, nuisance flies, mosquitoes, sand flies and black flies, among others, are included. Where applicable, significance of research is discussed.

Inactivation Of Feline Calicivirus And Adenovirus Type 40 By Uv Radiation, Jeanette A. Thurston-Enriquez, Charles N. Haas, Joseph Jacangelo, Kelley Riley, Charles P. Gerba

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Little information regarding the effectiveness of UV radiation on the inactivation of caliciviruses and enteric adenoviruses is available. Analysis of human calicivirus resistance to disinfectants is hampered by the lack of animal or cell culture methods that can determine the viruses’ infectivity. The inactivation kinetics of enteric adenovirus type 40 (AD40), coliphage MS-2, and feline calicivirus (FCV), closely related to the human caliciviruses based on nucleic acid organization and capsid architecture, were determined after exposure to low-pressure UV radiation in buffered demand-free (BDF) water at room temperature. In addition, UV disinfection experiments were also carried out in treated groundwater with …

Host Specificity Of The Leaf Beetle, Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae) From Asia, A Biological Control Agent For Saltcedars (Tamarix: Tamaricaceae) In The Western United States, C. Jack Deloach, Phil A. Lewis, John C. Herr, Raymond I. Carruthers, James L. Tracy, Joye Johnson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Four species of saltcedars, Tamarix ramosissima Ledeb., Tamarix chinensis Lour., Tamarix parviflora DC., and T. canariensis Willd. and their hybrids, are exotic, invasive small trees from Asia that cause great damage to riparian ecosystems of the western United States. They displace native plant communities, degrade wildlife habitat (including that of many endangered species), increase soil salinity and wildfires, lower water tables, reduce water available for agriculture and municipalities, and reduce recreational use of affected areas. Phytophagous insects are abundant on saltcedar in the Old World and we selected Diorhabda elongata Brullé deserticola Chen as the top candidate biological control agent …

Biology Of Diorhabda Elongata Deserticola (Coleoptera: Chrysomelidae), An Asian Leaf Beetle For Biological Control Of Saltcedars (Tamarix Spp.) In The United States, Phil A. Lewis, C. Jack Deloach, Allen E. Knutson, James L. Tracy, Thomas O. Robbins

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Adults and larvae of Diorhabda elongata Brullé subspecies deserticola Chen feed on the foliage of saltcedars (Tamarix spp.). All three instars are black, the 2nd with an indistinct, and the 3rd with a distinct yellowish lateral stripe; full-grown larvae reach ca. 9mm in length and pupate in cells in litter on the ground or a few cm below the soil surface. Adults are yellowish with two dark brown stripes on each elytron. Duration of the egg averaged 5 days, 1st instar 4.9 days, 2nd instar 4.8 days, 3rd instar 7.4 days, prepupa 4.8 days, and pupa 7.1 days at …

Large Summer Population Of Multicolored Asian Lady Beetle In North Dakota, Louis S. Hesler

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The multicolored Asian lady beetle (Harmonia axyridis), hereafter MALB, is a Palearctic species that established relatively recently in eastern (Chapin and Brou 1991) and western North America (Dreistadt et a1. 1995). Populations of MALB have expanded throughout eastern North America (McCorquodale 1998) and among western coastal states (LaMana and Miller 1996). MALB was discovered in North Dakota in September 2000 (Fauske et a1. 2003). It currently is known from seven counties in eastern and northern North Dakota, based on one to two specimens per county (Fauske et al. 2003). MALB also has been found in South Dakota and …

Reduction Of High Soil Test Phosphorus By Corn And Soybean Varieties, Bahman Eghball, J.F. Shanahan, Gary E. Varvel, John Gilley

Department of Agronomy and Horticulture: Faculty Publications

Soils with high levels of P can contribute to excess P in runoff and subsequently pollute the surface water. Excess P in the soil can be removed from the system by harvesting crops. The objectives of this study were to evaluate corn (Zea mays L.) P removal effects on soil P reduction, and to evaluate various corn hybrids and soybean [Glycine max (L.) Merr.] varieties for differences in grain P concentration and P removal. Soil with varying P levels as a result of annual or biennial beef cattle (Bos taurus) feedlot manure or compost appli- enough …

Detecting Stress In Glasshouse Plants Using Color Infrared Imagery: A Potential New Application For Remote Sensing, Kenneth R. Summy, Christopher R. Little, Ruben A. Mazariegos, James H. Everitt, M. R. Davis, J. V. French, A. W. Scott Jr.

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

English: Studies were conducted to evaluate the effectiveness of color infrared (CIR) film for detecting physiological stress in plants located within glasshouse structures. Spectroradiometer measurements obtained within and outside of a structure constructed of polycarbonate plastic indicated no significant attenuation or disruption of visible and near-infrared radiation entering the structure. CIR photographs of cucumber seedlings (Cucumis sativus) obtained within the greenhouse were comparable in quality to those obtained outside the structure, and clearly distinguished between foliage of healthy plants and those subjected to a moderate level of nitrogen stress. In CIR imagery of a trifoliate orange tree (Poncirus trifoliata (L.) …

Effects Of Western Corn Belt Cropping Systems On Agroecosystem Functions, Mark Liebig, Gary E. Varvel

Department of Agronomy and Horticulture: Faculty Publications

Agricultural sustainability is enhanced by management practices that optimize the performance of multiple agroecosystem functions. The performance of western Corn Belt cropping systems was evaluated based on four agroecosystem functions: food production, raw materials production, nutrient cycling, and greenhouse gas regulation. A simple multiattribute ranking procedure was used to quantify agroecosystem performance using data from a long-term cropping systems experiment near Mead, NE. Treatments included in the procedure were continuous corn (Zea mays L.) (CC), corn–soybean [Glycine max (L.) Merr.] (C–SB), corn–oat (Avena sativa L.) _ clover [80% sweet clover (Melilotus officinalis L.) and 20% red …

An Overview Of Aircraft Remote Sensing In Integrated Pest Management, James H. Everitt, Kenneth R. Summy, D. E. Escobar, M. R. Davis

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

English: This paper presents four exemplary applications of aerial photography and videography, global positioning system (GPS), and geographic information system (GIS) technologies for detecting, monitoring, and mapping insect infestations in agriculture, forestry, and rangeland areas. Applications demonstrated include detecting and mapping: (1) citrus blackfly (Aleurocanthus woglumi Ashby) infestations in citrus orchards; (2) silverleaf whitefly (Bemisia argentifolii Bellows and Perring) infestations in cotton; (3) harvester ant (Pogonomyrmex barbatus F. Smith) infestations on rangelands; and (4) western pine beetle (Dendroctonus brevicomis LeConte) infestations in a forested area. The integration of a GPS with the video imagery permitted latitude and longitude coordinates of …

Cissus Sicyoides C. Linnaeus (Vitaceae), A Potential Exotic Pest In The Lower Rio Grande Valley, Texas, J. V. French, Robert I. Lonard, James H. Everitt

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

English:Cissus sicyoides C. Linnaeus, a perennial vine native to tropical Mexico, Central America, and the Caribbean, has recently been rediscovered in the Lower Rio Grande Valley,Texas. A dense population of this exotic species has been located in a brushy area along a canal network and in two adjacent citrus groves near Weslaco. This species produces a dense mantle that covers other vegetation, appears to be invasive, and may pose a potential weed problem in citrus in the Lower Rio Grande Valley.

Spanish: Cissus sicyoides C. Linnaeus, una enredadera perene nativa de los trópicos de México, América Central y el Caribe, …

Pioneering Biotechnological Works On Hordeum Vulgare L. Cvs Performed In Collaboration With The İstanbul University Biology Department And The Tübi̇tak Research Institute For Genetic Engineering And Biotechnology, Nermi̇n Gözükirmizi

Turkish Journal of Botany

Hordeum vulgare L. (barley) is an important cereal crop and is also an excellent model organism for biochemists, physiologists, geneticists and molecular biologists. H. vulgare cvs. have been used as a model system for almost 30 years at the Biology Department of İstanbul University, İstanbul-Turkey. The first studies on experimental mutagenesis were followed by tissue culture, gene transfers, DNA marker applications and finally DNA arrays which, progressed further after the 1990 when collaboration was established with the Plant Biotechnology group at the TÜBİTAK Research Institute for Genetic Engineering and Biotechnology in Gebze, Kocaeli-Turkey. This review article outlines the results of …

Studies On Rice Transformation And The Use Of Transformed Plants [Electronic Resource], Qiming Shao

LSU Doctoral Dissertations

This research was conducted to enhance utilization of the Liberty herbicide resistance transgene in rice. Non-lethal methods to determine the sensitivity of transgenic rice plants to hygromycin B and Liberty were developed, tested and used in this research. Four homozygous transformed plants were selected to make reciprocal crosses with their non-transformed parent cultivars Taipei 309 and Nipponbare. Their resistances to Liberty and hygromycin B were controlled by the closely linked single dominant genes bar and hpt. Some non-resistant phenotypes in the F2 populations were due to gene silencing. The bar gene in some of these plants were allelic and some …