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2006

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Articles 2731 - 2760 of 3150

Full-Text Articles in Life Sciences

Sentinel Nematodes Of Land-Use Change And Restoration In Tallgrass Prairie, T. C. Todd, T. O. Powers, P.G. Mullin Jan 2006

Sentinel Nematodes Of Land-Use Change And Restoration In Tallgrass Prairie, T. C. Todd, T. O. Powers, P.G. Mullin

Department of Plant Pathology: Faculty Publications

Changes in land use and the associated changes in land cover are recognized as the most important component of human-induced global change. Much attention has been focused on deforestation, but grasslands are among the most endangered ecosystems on Earth. The North American tallgrass prairie is a dramatic example, exhibiting a greater than 95% decline in historical area. Renewed interest in prairie conservation and restoration has highlighted the need for ecological indicators of disturbance and recovery in native systems, including the below ground component. The tallgrass prairie differs from the agricultural systems that have replaced it in having greater diversity and …

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First Report Of Leaf Spot Of Smooth Bromegrass Caused By Pithomyces Chartarum In Nebraska, C. Eken, C. C. Jochum, G. Y. Yuen Jan 2006

First Report Of Leaf Spot Of Smooth Bromegrass Caused By Pithomyces Chartarum In Nebraska, C. Eken, C. C. Jochum, G. Y. Yuen

Department of Plant Pathology: Faculty Publications

Smooth bromegrass (Bromus inermis Leyss.) is the most common perennial grass species cultivated for forage in North America. During late fall of 2004, smooth bromegrass plants in Lincoln, NE were observed to have brown lesions on leaf midveins that were several centimeters long. Symptomatic leaves were surface disinfested for 1 min in 2% NaOCl and incubated at 25°C on potato dextrose agar (PDA) and water agar. The fungus, Pithomyces chartarum (Berk. & Curt) Ellis, was isolated consistently and identified on the basis of morphological characteristics (1). Colonies were effused and black on PDA. Conidiophores measured 3.5 to 8 …

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Bioinformatics-Enabled Identification Of The Hrpl Regulon And Type Iii Secretion System Effector Proteins Of Pseudomonas Syringae Pv. Phaseolicola 1448a, Monica Vencato, Fang Tian, James R. Alfano, C. Robin Buell, Samuel Cartinhour, Genevieve A. Declerck, David S. Guttman, John Stavrinides, Vinita Joardar, Magdalen Lindeberg, Philip A. Bronstein, John W. Mansfield, Christopher R. Myers, Alan Collmer, David J. Schneider Jan 2006

Bioinformatics-Enabled Identification Of The Hrpl Regulon And Type Iii Secretion System Effector Proteins Of Pseudomonas Syringae Pv. Phaseolicola 1448a, Monica Vencato, Fang Tian, James R. Alfano, C. Robin Buell, Samuel Cartinhour, Genevieve A. Declerck, David S. Guttman, John Stavrinides, Vinita Joardar, Magdalen Lindeberg, Philip A. Bronstein, John W. Mansfield, Christopher R. Myers, Alan Collmer, David J. Schneider

Department of Plant Pathology: Faculty Publications

The ability of Pseudomonas syringae pv. phaseolicola to cause halo blight of bean is dependent on its ability to translocate effector proteins into host cells via the hypersensitive response and pathogenicity (Hrp) type III secretion system (T3SS). To identify genes encoding type III effectors and other potential virulence factors that are regulated by the HrpL alternative sigma factor, we used a hidden Markov model, weight matrix model, and type III targeting-associated patterns to search the genome of P. syringae pv. phaseolicola 1448A, which recently was sequenced to completion. We identified 44 high-probability putative Hrp promoters upstream of genes encoding the …

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Regulation Of Hyphal Morphogenesis And The Dna Damage Response By The Aspergillus Nidulans Atm Homolog Atma, Iran Malavazi, Camile P. Semighini, Marcia Regina Von Zeska Kress, Steven D. Harris, Gustavo H. Goldman Jan 2006

Regulation Of Hyphal Morphogenesis And The Dna Damage Response By The Aspergillus Nidulans Atm Homolog Atma, Iran Malavazi, Camile P. Semighini, Marcia Regina Von Zeska Kress, Steven D. Harris, Gustavo H. Goldman

Department of Plant Pathology: Faculty Publications

Ataxia telangiectasia (A-T) is an inherited disorder characterized by progressive loss of motor function and susceptibility to cancer. The most prominent clinical feature observed in A-T patients is the degeneration of Purkinje motor neurons. Numerous studies have emphasized the role of the affected gene product, ATM, in the regulation of the DNA damage response. However, in Purkinje cells, the bulk of ATM localizes to the cytoplasm and may play a role in vesicle trafficking. The nature of this function, and its involvement in the pathology underlying A-T, remain unknown. Here we characterize the homolog of ATM (AtmA) in the filamentous …

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Effect Of Nitrogen Addition On The Comparative Productivity Of Corn And Velvetleaf (Abutilon Theophrasti), Darren C. Barker, Stevan Z. Knezevic, Alex R. Martin, Daniel T. Walters, John L. Lindquist Jan 2006

Effect Of Nitrogen Addition On The Comparative Productivity Of Corn And Velvetleaf (Abutilon Theophrasti), Darren C. Barker, Stevan Z. Knezevic, Alex R. Martin, Daniel T. Walters, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Weeds that respond more to nitrogen fertilizer than crops may be more competitive under high nitrogen (N) conditions. Therefore, understanding the effects of nitrogen on crop and weed growth and competition is critical. Field experiments were conducted at two locations in 1999 and 2000 to determine the influence of varying levels of N addition on corn and velvetleaf height, leaf area, biomass accumulation, and yield. Nitrogen addition increased corn and velvetleaf height by a maximum of 15 and 68%, respectively. N addition increased corn and velvetleaf maximum leaf area index (LAI) by up to 51 and 90%. Corn and velvetleaf …

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Interference Effects In The Memory For Serially Presented Locations In Clark’S Nutcrackers, Nucifraga Columbiana, Jody L. Lewis, Alan C. Kamil Jan 2006

Interference Effects In The Memory For Serially Presented Locations In Clark’S Nutcrackers, Nucifraga Columbiana, Jody L. Lewis, Alan C. Kamil

Papers in Behavior in Biological Sciences

The authors tested the spatial memory of serially presented locations in Clark’s nutcrackers (Nucifraga columbiana). Birds were serially presented with locations in an open room. The authors buried a seed in a sand-filled cup at each location and then tested nutcrackers for their memory for each location in the list by using the cluster method. For each item in the list, the authors opened a cluster of 6 holes. Accuracy was measured by how many tries were required for the bird to find the correct location within each cluster. In Experiments 1 and 2, the authors presented 2 …

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Selective Attention, Priming, And Foraging Behavior, Alan Kamil, Alan B. Bond Jan 2006

Selective Attention, Priming, And Foraging Behavior, Alan Kamil, Alan B. Bond

Papers in Behavior in Biological Sciences

Animals selectively filter and transform their sensory input, increasing the accuracy with which some stimuli are detected and effectively ignoring others. This filtering process, collectively referred to as “selective attention,” takes place at a variety of different levels in the nervous system. It was described in considerable detail by William James over a century ago (James, 1890/1950) and has been a principal focus of research in cognitive psychology for nearly 50 years (Parasuraman & Davies, 1984; Pashler, 1998; Richards, 1998). Investigations of selective attention have also been central to the study of animal cognition, where the process of attention has …

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S-Adenosylmethionine Stabilizes Cystathionine Β-Synthase And Modulates Redox Capacity, Anna Prudova, Zachary Bauman, Aaron Braun, Victor Vitvitsky, Shelly C. Lu, Ruma Banerjee Jan 2006

S-Adenosylmethionine Stabilizes Cystathionine Β-Synthase And Modulates Redox Capacity, Anna Prudova, Zachary Bauman, Aaron Braun, Victor Vitvitsky, Shelly C. Lu, Ruma Banerjee

Department of Biochemistry: Faculty Publications

The transsulfuration pathway converts homocysteine to cysteine and represents the metabolic link between antioxidant and methylation metabolism. The first and committing step in this pathway is catalyzed by cystathionine β-synthase (CBS), which is subject to complex regulation, including allosteric activation by the methyl donor, S-adenosylmethionine (AdoMet). In this study, we demonstrate that methionine restriction leads to a >10-fold decrease in CBS protein levels, and pulse proteolysis studies reveal that binding of AdoMet stabilizes the protein against degradation by ≈12 kcal/mol. These observations predict that under pathological conditions where AdoMet levels are diminished, CBS, and therefore glutathione levels, will be reduced. …

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Microsatellite Genotyping To Distinguish Colonies And Intraspecies Genetic Variation In The Eastern Subterranean Termite, Reticulitermes Flavipes (Isoptera: Rhinotermitidae), Timothy J. Husen, Shripat T. Kamble, Julie M. Stone Jan 2006

Microsatellite Genotyping To Distinguish Colonies And Intraspecies Genetic Variation In The Eastern Subterranean Termite, Reticulitermes Flavipes (Isoptera: Rhinotermitidae), Timothy J. Husen, Shripat T. Kamble, Julie M. Stone

Department of Biochemistry: Faculty Publications

Microsatellite markers and fingerprinting techniques have demonstrated great potential for assessing colony affiliation in Reticulitermes species. This study utilized microsatellite allele fingerprints and examined variation at eight micro satellite loci within five different R. flavipes collection sites in each of Lancaster and Madison counties in Nebraska. In the termite populations from Lancaster County, five of the eight microsatellite loci (Rf 1-3, Rf 3-1, Rf 5-1 0, Rf 6-1, and Rf 24-2) provided informative genotypic variability allowing colony distinction. DNA sequence data at locus Rf24-2 also provided conclusive evidence that populations sampled were distinct colonies. Five micro satellite loci (Rf 3-1, …

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Sex-Specific Expression Of Alternative Transcripts In Drosophila, Lauren Mcintyre, Lisa Bono, Anne Genissel, Rick Westerman, Damion Junk, Marina Telonis-Scott, Lawrence G. Harshman, Marta Wayne, Artyom Kopp, Sergey V. Nuzhdin Jan 2006

Sex-Specific Expression Of Alternative Transcripts In Drosophila, Lauren Mcintyre, Lisa Bono, Anne Genissel, Rick Westerman, Damion Junk, Marina Telonis-Scott, Lawrence G. Harshman, Marta Wayne, Artyom Kopp, Sergey V. Nuzhdin

School of Biological Sciences: Faculty Publications

Background: Many genes produce multiple transcripts due to alternative splicing or utilization of alternative transcription initiation/termination sites. This 'transcriptome expansion' is thought to increase phenotypic complexity by allowing a single locus to produce several functionally distinct proteins. However, sex, genetic and developmental variation in the representation of alternative transcripts has never been examined systematically. Here, we describe a genome-wide analysis of sex-specific expression of alternative transcripts in Drosophila melanogaster.

Results: We compared transcript profiles in males and females from eight Drosophila lines (OregonR and 2b, and 6 RIL) using a newly designed 60-mer oligonucleotide microarray that allows us …

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Spillover Of Agriculturally Subsidized Predators As A Potential Threat To Native Insect Herbivores In Fragmented Landscapes, Tatyana A. Rand, Svata M. Louda Jan 2006

Spillover Of Agriculturally Subsidized Predators As A Potential Threat To Native Insect Herbivores In Fragmented Landscapes, Tatyana A. Rand, Svata M. Louda

School of Biological Sciences: Faculty Publications

Habitat loss and fragmentation can have strong negative impacts on populations of some native species. Spillover of generalist natural enemies from the surrounding landscape matrix is one mechanism potentially generating such effects, yet this has been rarely studied in insects. We examined the influence of habitat conversion to agriculture on the abundance and potential effects of predatory coccinellid beetles on native insect herbivores within 12 grassland remnants in central Nebraska (U.S.A.). Results of sweep sampling revealed that coccinellids were three to six times more abundant at native grassland sites embedded within cropland- dominated landscapes compared with control sites in grassland-dominated …

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The Pea Aphid, Acyrthosiphon Pisum: An Emerging Genomic Model System For Ecological, Developmental, And Evolutionary Studies, Jennifer A. Brisson, David L. Stern Jan 2006

The Pea Aphid, Acyrthosiphon Pisum: An Emerging Genomic Model System For Ecological, Developmental, And Evolutionary Studies, Jennifer A. Brisson, David L. Stern

School of Biological Sciences: Faculty Publications

Aphids display an abundance of adaptations that are not easily studied in existing model systems. Here we review the biology of a new genomic model system, the pea aphid, Acyrthosiphon pisum. We then discuss several phenomena that are particularly accessible to study in the pea aphid: the developmental genetic basis of polyphenisms, aphid–bacterial symbioses, the genetics of adaptation and mechanisms of virus transmission. The pea aphid can be maintained in the laboratory and natural populations can be studied in the field. These properties allow controlled experiments to be performed on problems of direct relevance to natural aphid populations. Combined …

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Assembly Of The Eastern North American Herpetofauna: New Evidence From Lizards And Frogs, J. Robert Macy, James A. Schulte Ii, Jared L. Strasburg, Jennifer A. Brisson, Allan Larson, Natalia B. Ananjeva, Yuezhao Wang, James F. Parham, Theodore J. Papenfuss Jan 2006

Assembly Of The Eastern North American Herpetofauna: New Evidence From Lizards And Frogs, J. Robert Macy, James A. Schulte Ii, Jared L. Strasburg, Jennifer A. Brisson, Allan Larson, Natalia B. Ananjeva, Yuezhao Wang, James F. Parham, Theodore J. Papenfuss

School of Biological Sciences: Faculty Publications

Darwin first recognized the importance of episodic intercontinental dispersal in the establishment of worldwide biotic diversity. Faunal exchange across the Bering Land Bridge is a major example of such dispersal. Here, we demonstrate with mitochondrial DNA evidence that three independent dispersal events from Asia to North America are the source for almost all lizard taxa found in continental eastern North America. Two other dispersal events across Beringia account for observed diversity among North American ranid frogs, one of the most species-rich groups of frogs in eastern North America. The contribution of faunal elements from Asia via dispersal across Beringia is …

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Anatomy And Physiology Of Giant Neurons In The Antenniform Leg Of The Amblypygid Phrynus Marginemaculatus, A. J. Spence, Eileen Hebets Jan 2006

Anatomy And Physiology Of Giant Neurons In The Antenniform Leg Of The Amblypygid Phrynus Marginemaculatus, A. J. Spence, Eileen Hebets

Eileen Hebets Publications

Amblypygids have modified front legs that are not used for locomotion, but rather to probe the environment in the manner of antennae. These elongate, motile sense organs are referred to as antenniform legs. We have found remarkable replication in structure and function of giant neurons in the antenniform leg of the amblypygid Phrynus marginemaculatus C.L. Koch 1841 when compared with other amblypygids. These neurons have such large diameter axons (several μm) that their action potentials can be recorded outside the cuticle. Their cell bodies are found in the periphery, in the distal-most segments of the antenniform leg, centimeters away from …

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Premature Induction Of An Immunosuppressive Regulatory T Cell Response During Acute Simian Immunodeficiency Virus Infection, Jacob D. Estes, Qingsheng Li, Matthew R. Reynolds, Stephen W. Wietgrefe, Lijie Duan, Timothy Schacker, Louis J. Picker, David I. Watkins, Jeffrey D. Lifson, Cavan Reilly, John V. Carlis, Ashley T. Haase Jan 2006

Premature Induction Of An Immunosuppressive Regulatory T Cell Response During Acute Simian Immunodeficiency Virus Infection, Jacob D. Estes, Qingsheng Li, Matthew R. Reynolds, Stephen W. Wietgrefe, Lijie Duan, Timothy Schacker, Louis J. Picker, David I. Watkins, Jeffrey D. Lifson, Cavan Reilly, John V. Carlis, Ashley T. Haase

Qingsheng Li Publications

Here we report the results of an investigation into the possibility that one mechanism responsible for the establishment of persistent human immunodeficiency virus infection is an early regulatory T (Treg) cell response that blunts virus- specific responses. Using the simian immunodeficiency virus (SIV)–infected rhesus macaque model, we show that, indeed, viral replication and immune activation in lymphatic tissue drive a premature immunosuppressive response, with dramatic increases in the frequencies of CD4+CD25+FOXP3+ Treg cells, transforming growth factor–β1+ cells, interleukin–10+ cells, and indoleamine 2,3-dioxygenase+CD3+ cells.When we compared SIV infection with rhesus cytomegalovirus (RhCMV) …

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Parelaphostrongylus Odocoilei In Columbia Black-Tailed Deer From Oregon, Jack A. Mortenson, Arthur Abrams, Benjamin M. Rosenthal, Detiger Dunams, Eric P. Hoberg, Robert J. Bildfell, Richard L. Green Jan 2006

Parelaphostrongylus Odocoilei In Columbia Black-Tailed Deer From Oregon, Jack A. Mortenson, Arthur Abrams, Benjamin M. Rosenthal, Detiger Dunams, Eric P. Hoberg, Robert J. Bildfell, Richard L. Green

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Documenting the occurrence of Parelaphostrongylus odocoilei has historically relied on the morphological examination of adult worms collected from the skeletal muscle of definitive hosts, including deer. Recent advances in the knowledge of protostrongylid genetic sequences now permit larvae to be identified. Dorsal-spined larvae (DSLs) collected in 2003–2004 from the lung and feces of six Columbian black-tailed deer (Odocoileus hemionus columbianus) from Oregon were characterized genetically. The sequences from unknown DSLs were compared to those from morphologically validated adults and larvae of P. odocoilei at both the second internal transcribed spacer (ITS-2) of ribosomal DNA and the mitochondrial cytochrome …

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Heuermann Recognition Luncheon, John Owens Jan 2006

Heuermann Recognition Luncheon, John Owens

John Owens: Speeches and Appearances

No abstract provided.

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Dinsdale Family Luncheon, John Owens Jan 2006

Dinsdale Family Luncheon, John Owens

John Owens: Speeches and Appearances

Today we celebrate and honor the 2006 recipients of the Dinsdale Family Faculty Awards, made possible by the generosity of the Dinsdale family.

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The Sedimentary Environment Below Earth’S Polar Ice Cap As A Microbial Habitat, David C. Smith, Stephanie Forschner-Dancause, David C. Rowley, Steven D'Hondt Jan 2006

The Sedimentary Environment Below Earth’S Polar Ice Cap As A Microbial Habitat, David C. Smith, Stephanie Forschner-Dancause, David C. Rowley, Steven D'Hondt

Graduate School of Oceanography Faculty Publications

University of Rhode Island faculty participated in drilling of the polar ice cap to study microbial diversity and adaptation to subsurface life under conditions that may mimic extraterrestrial subsurface conditions.

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Infiltration And Short-Term Movement Of Nitrogen In A Silt-Loam Soil Typical Of Rice Cultivation In Arkansas, Lindsay M. Copenhaver, Mary C. Savin, David M. Miller, Peter J. Tomlinson, Kristofor R. Brye, Richard J. Norman Jan 2006

Infiltration And Short-Term Movement Of Nitrogen In A Silt-Loam Soil Typical Of Rice Cultivation In Arkansas, Lindsay M. Copenhaver, Mary C. Savin, David M. Miller, Peter J. Tomlinson, Kristofor R. Brye, Richard J. Norman

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Rice production in Arkansas is one of the top three crop commodities in terms of cash receipts. Researchers and farmers report that nitrogen (N) needs to be managed according to a variety of factors with two important ones being soil and fertilizer type. The objectives of this experiment were to determine: 1) the degree to which floodwater-incorporated N applied as urea or as ammonium sulfate infiltrates intact cores (7.2-cm dia., 10-cm depth) containing DeWitt silt-loam soil, and 2) the distribution of N during 12 h of ponding. Inorganic-N concentrations were analyzed at 2-cm depth intervals in cores following removal of …

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Effects Of Tank Mixes Of Mon 3539 And Selected Compounds In Roundupready Flex® Cotton – 2005, Jarrod Hardke, Gus Lorenz, Kyle Colwell, Craig Shelton Jan 2006

Effects Of Tank Mixes Of Mon 3539 And Selected Compounds In Roundupready Flex® Cotton – 2005, Jarrod Hardke, Gus Lorenz, Kyle Colwell, Craig Shelton

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Field experiments were conducted in 2005 to evaluate potential weed control interactions when MON 3539 (glyphosate) was applied with several insecticides and a plant growth regulator to RoundupReady Flex® cotton. Applications were made at the 1-3 leaf stage, the 6-8 node stage, and at the 12-14 node stage. Different combinations of tank mixes were used in each of the three applications. In the first application, all plots received the same treatment: MON 3539 at a rate of 0.75 lb ae/a. A second application was made to evaluate crop injury. Only the MON 3539 + Dimate (dimethoate) mixture significantly increased crop …

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Study Of Metals In Leached Soils Of A Municipal Dumpsite In Tampico, Tamaulipas, Mexico: Preliminary Results, P. F. Rodríguez-Espinosa, D. Chazaro Mendoza, J. A. Montes De Oca, G. Sánchez Torres E., Alejandro Fierro-Cabo Jan 2006

Study Of Metals In Leached Soils Of A Municipal Dumpsite In Tampico, Tamaulipas, Mexico: Preliminary Results, P. F. Rodríguez-Espinosa, D. Chazaro Mendoza, J. A. Montes De Oca, G. Sánchez Torres E., Alejandro Fierro-Cabo

School of Earth, Environmental, & Marine Sciences Faculty Publications

The Zapote dumpsite measures 420000 m 2 and is 28 years old; an estimated 2.5 millions tons of waste have accumulated on the site (household waste, clinical waste, commercial waste). The thickness of the waste is 3 to 9 meters. Since operations began, no control regulations have existed on the residues received. The Zapote dumpsite is located within a salt-marsh between a system of channels and river lagoons of brackish water, located in a tropical sedimentary environment in the urban zone of Tampico, Tamaulipas, Mexico. Recently, the Zapote has been closed and work is presently underway in its rehabilitation since …

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Foraging Behavior And Success Of Herons And Egrets In Natural And Artificial Wetlands, Henry Dewayne Mincey Jan 2006

Foraging Behavior And Success Of Herons And Egrets In Natural And Artificial Wetlands, Henry Dewayne Mincey

College of Graduate Studies: Theses & Dissertations

The southeastern United States has approximately 13.2 million hectares of wetland habitat, but these sensitive areas are subject to loss and degradation from draining and development. The effects, both positive and negative, that manipulation of these wetlands have on wildlife is still under study. In particular, there is a need to know whether artificial (mitigated) wetlands can serve as an appropriate substitute for the loss of natural wetlands. Therefore, I quantified the foraging behavior of herons and egrets (species that are dependent on wetlands for food) in natural and artificial wetlands in southeastern coastal Georgia and southern coastal South Carolina. …

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The Winter Ecology Of The Piping Plover (Charadrius Melodus) In Coastal Georgia, Brandon Lennon Noel Jan 2006

The Winter Ecology Of The Piping Plover (Charadrius Melodus) In Coastal Georgia, Brandon Lennon Noel

College of Graduate Studies: Theses & Dissertations

Author's abstract: The Piping Plover (Charadrius melodus) is a federally listed species with three distinct breeding populations, including Great Plains (threatened), Great Lakes (endangered), and Atlantic Coast (threatened), all of which winter along the Atlnatic and Gulf coasts of the United States. I studied the winter ecology of the Piping Plovers on Little St. Simons Island (LSSI), Georgia, from 2003-2006, with emphasis on the conservation significance of this site for the endangered Great Lakes population. During 2003-2004 and 2004-2005, LSSI supported up to 100 Piping Plovers during peak migration, and approximately 40 birds wintered at this site. All populations had …

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Molecular Population Genetics Of The Atlantic Sand Fiddler Crab, Uca Pugilator, Along The Atlantic Coast, David A. Weese Jan 2006

Molecular Population Genetics Of The Atlantic Sand Fiddler Crab, Uca Pugilator, Along The Atlantic Coast, David A. Weese

College of Graduate Studies: Theses & Dissertations

Author's abstract: The Atlantic sand fiddler crab, Uca pugilator, is an extremely abundant fiddler crab found along the eastern and Gulf coast of the United States. Fiddler crabs have a life cycle with an obligatory planktonic larval phase of 30-90 days, which might be expected to lead to widespread larval dispersal and consequent genetic homogeneity over considerable distances. However a large amount of morphological and behavioral variation is found between northern and southern populations along the eastern coast. This study was undertaken to determine the population genetic structure of U. pugilator and to determine whether these differences may have a …

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Effects Of Dosages And Application Periods Of Edta On Morphological And Cytogenetic Characters Of Barley (Hordeum Vulgare L.) Seedlings, Ali̇ İrfan İlbaş, Yasemi̇n Eroğlu, Hali̇l Erhan Eroğlu Jan 2006

Effects Of Dosages And Application Periods Of Edta On Morphological And Cytogenetic Characters Of Barley (Hordeum Vulgare L.) Seedlings, Ali̇ İrfan İlbaş, Yasemi̇n Eroğlu, Hali̇l Erhan Eroğlu

Turkish Journal of Biology

Ethylenediaminetetraacetic acid (EDTA) has many applications in plant research in addition to other applications, such as chelation and medical therapy. The morphological and cytogenetic effects of EDTA on barley seedlings were investigated in the present study. Seeds of Hordeum vulgare L. were treated with different doses of EDTA (30, 60, 90, 120 and 150 mmol/l) and 2 different application periods (20 and 22 h). Except mitotic index, all of the measurements for the investigated characters were carried out on days 7 and 14. EDTA treatments affected germination rates in nearly all treatments. In general, EDTA treatments decreased the root, leaf …

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Biological Activities Of The Essential Oil And Methanol Extract Of Achillea Biebersteinii Afan. (Asteraceae), Özlem Bariş, Medi̇ne Güllüce, Fi̇kretti̇n Şahi̇n, Hakan Özer, Hamdullah Kiliç, Hakan Özkan, Münevver Sökmen, Tüli̇n Özbek Jan 2006

Biological Activities Of The Essential Oil And Methanol Extract Of Achillea Biebersteinii Afan. (Asteraceae), Özlem Bariş, Medi̇ne Güllüce, Fi̇kretti̇n Şahi̇n, Hakan Özer, Hamdullah Kiliç, Hakan Özkan, Münevver Sökmen, Tüli̇n Özbek

Turkish Journal of Biology

The present work examined the in vitro antimicrobial and antioxidant activities of the essential oil and methanol extract from Achillea biebersteinii Afan. (Asteraceae). The essential oil exhibited antimicrobial activity against 8 bacteria, 14 fungi and the yeast C. albicans, whereas methanolic extract remained inactive. The antioxidative capacity of the samples was evaluated by using DPPH (2,2-diphenyl-1-picrylhydrazyl) and b-carotene/linoleic acid assays. In both assays, the extract showed better antioxidative capacity than the oil. The extract reduced the stable free radical DPPH with lower IC50 value (89.90 µg/ml) than the oil (8900 µg/ml). In the b-carotene/linoleic acid assay, the samples were not …

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Some Optimal Cultural Parameters For Gibberellic Acid Biosynthesis By Pseudomonas Sp., Şafak Karakoç, Ni̇lüfer Aksöz Jan 2006

Some Optimal Cultural Parameters For Gibberellic Acid Biosynthesis By Pseudomonas Sp., Şafak Karakoç, Ni̇lüfer Aksöz

Turkish Journal of Biology

The current study reports the optimal cultural parameters for GA3 production by Pseudomonas sp. isolated from wastes of processed olive affected by physiological conditions (incubation temperature, pH of the growth media, incubation period, and incubation conditions). The highest level of gibberellic acid (285.06 mg/l) production was obtained in nutrient broth when the bacteria culture was incubated at 30 °C for 72 h at pH 7 on rotary shaker and in the dark.

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Physical And Sensoric Attributes Of Flaxseed Flour Supplemented Cookies, Shahzad Hussain, Faqir Muhammad Anjum, Masood Sadiq Butt, Muhammad Issa Khan, Ali Asghar Jan 2006

Physical And Sensoric Attributes Of Flaxseed Flour Supplemented Cookies, Shahzad Hussain, Faqir Muhammad Anjum, Masood Sadiq Butt, Muhammad Issa Khan, Ali Asghar

Turkish Journal of Biology

Full fat flaxseed flour was supplemented with wheat flour @ 5, 10, 15, 20,25 and 30%. Cookies were prepared from composite flours. Cookies prepared without flaxseed flour were kept as control. The mean quality score of the cookies decreased with the increase in the level of the flaxseed flour supplementation. Colour and crispiness of the cookies showed a declining trend as compared to flavour and texture of cookies. Cookies containing 20% and lower level of the full fat flaxseed flour were acceptable in relation to their overall acceptability. Significant reduction in the spread factor of the cookies was observed. Addition …

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Colchicine-Induced Tetraploidy And Changes In Allele Frequencies In Colchicine-Treated Populations Of Diploids Assessed With Rapd Markers In Gossypium Arboreum L., Saeed Rauf, Iftikhar Ahmad Khan, Faroog Ahmad Khan Jan 2006

Colchicine-Induced Tetraploidy And Changes In Allele Frequencies In Colchicine-Treated Populations Of Diploids Assessed With Rapd Markers In Gossypium Arboreum L., Saeed Rauf, Iftikhar Ahmad Khan, Faroog Ahmad Khan

Turkish Journal of Biology

Two cultivars of cotton G. arboreum L. cv. FDH-228 and HK-113 were treated with colchicine solution (1%) with 3 methods of application. Colchicine application at the seedling stage on shoot apex was successful. Tetraploid plants of arboreum (4x = 2n = 52) had larger vegetative, reproductive parts, but less frequent stomata and higher optical density of DNA than their normal diploid counterparts (2n = 26). Results also showed that individuals that escaped the duplicating effects of colchicine although treated, presented significant point mutagenic effects. Randomly Amplified Polymorphic DNA markers were used to evaluate diversity and similarities in populations treated with …

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