Digital Commons Network^™

Critical Period For Weed Control: The Concept And Data Analysis, Stevan Z. Knezevic, Sean P. Evans, Erin E. Blankenship, Rene C. Van Acker, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

The critical period for weed control (CPWC) is a period in the crop growth cycle during which weeds must be controlled to prevent yield losses. Knowing the CPWC is useful in making decisions on the need for and timing of weed control and in achieving efficient herbicide use from both biological and economic perspectives. An increase in the use of herbicide-tolerant crops, especially soybean resistant to glyphosate, has stimulated interest in the concept of CPWC. Recently, several studies examined this concept in glyphosate-resistant corn and soybean across the midwestern United States. However, these studies presented various methods for data analysis …

Growth Response Of Velvetleaf To Three Postemergence Herbicides, Cheryl A. Murphy, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Knowledge of how reduction in the rate of herbicide application or rotation of their mode of action influences weed growth will provide insight into how successful these practices will be in an integrated weed management program. Field experiments were conducted in 1996 and 1997 to quantify velvetleaf growth response to three postemergence herbicides, each with a different mode of action. A monoculture of velvetleaf was treated with halosulfuron, dicamba, and flumiclorac at 0, 0.10, 0.25, 0.50, 0.75, and 1.0 X the labeled rate for weed control in corn. Percent plant mortality increased with rate of application; the greatest mortality occurred …

Genetic Analysis Of Feed Quality And Seed Weight Of Sorghum Inbred Lines And Hybrids Using Analytical Methods And Nirs, C. Hicks, M. R. Tuinstra, Jeffrey F. Pedersen, F. E. Dowell, K. D. Kofoid

Department of Agronomy and Horticulture: Faculty Publications

Eight lines of grain sorghum and their F1 hybrids were evaluated for contents of crude protein (CP), fat (FAT), and starch (STA); protein digestibility (PD); and in vitro dry matter disappearance (IVDMD). The effect of seed weight (SW) on these traits and the potential use of near infrared reflectance spectroscopy (NIRS) to predict them also were investigated. The male lines included three normal-seeded lines (TX2737, TX435, and P954063) and two largeseeded lines (PL-1 and Eastin1). The female lines included commonU.S. seed parent lines (Wheatland, Redlan, and SA3042). The lines and their hybrids were grown under dryland conditions at Kansas State …

Combinatorial Control Of Yeast Fet4 Gene Expression By Iron, Zinc, And Oxygen, Brian M. Waters, David J. Eide

Department of Agronomy and Horticulture: Faculty Publications

Acquisition of metals such as iron, copper, and zinc by the yeast Saccharomyces cerevisiae is tightly regulated. High affinity uptake systems are induced under metal-limiting conditions to maintain an adequate supply of these essential nutrients. Low affinity uptake systems function when their substrates are in greater supply. The FET₄ gene encodes a low affinity iron and copper uptake transporter. FET₄ expression is regulated by several environmental factors. In this report, we describe the molecular mechanisms underlying this regulation. First, we found that FET₄ expression is induced in iron-limited cells by the Aft1 iron-responsive transcriptional activator. Second, FET …

A Physically Based Two-Dimensional Infiltration Model For Furrow Irrigation, Christopher J. Skonard, Derrel L. Martin

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

A two-dimensional physically based infiltration model was developed for furrow
irrigation. Infiltration was simulated using the Green-Ampt infiltration method. The Green-Ampt infiltration parameters are available from numerous sources, unlike the Kostiakov infiltration parameters. Simulation tests showed the two-dimensional model capable of estimating cumulative infiltration volume within 8% compared to simulated infiltration using the finite element model, Hydrus-2D. Application of the two-dimensional model in a surface irrigation advance model allows irrigation performance parameters to be predicted without extensive soil experiments.

Heat Curing Of Soy Protein Films At Selected Temperatures And Pressures, Ki Myong Kim, Curtis Weller, Milford Hanna, Aristippos Gennadios

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Vacuum and temperature effects on moisture content, water vapor permeability (WVP), color (L, a, b, and DE), tensile strength (TS), elongation (E), and total soluble matter (TSM) of soy protein isolate (SPI) films were examined. SPI films were cured at 60, 72.5, or 85 °C and at 101.3, 81.32, or 61.32 kPa for 24 h. As a result of heat-curing moisture content, WVP, E, and TSM decreased, and total color difference and TS increased. Pressure, individually and interactively with temperature, significantly affected film moisture content, TS, and TSM.

Manure As Carbon Source For Soil Improvement And Crop Production: Site-Specific Application, Bahman Eghball, Daniel Ginting, Charles A. Shapiro, James S. Schepers, Christopher J. Bauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Manure, a renewable resource, is an excellent source of nutrients that can be substituted for synthetic types of fertilizers. The C in manure can enhance the physical and chemical properties of soils, especially infertile soils, as these soils typically contain low levels of organic matter and nutrients. The objective of this study was to evaluate the effects of C and nutrients in manure on soil C dynamics and crop production. The treatments included applications of site-specific manure (SSM), uniform manure (UM), uniform commercial fertilizer, and a no treatment check. Field strips 40 ft (16 corn rows) wide and 2200 ft …

Impact Of Manure Application On Phosphorus Runoff And Soil Erosion, Daniel T. Walters, C. Gossin, Gregory J. Teichmeier, Galen E. Erickson

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Phosphorus (P) losses from agricultural land is a serious environmental issue because of the impact of P on freshwater eutrophication (McDowell, et al., 2001). The movement of P from soil to surface water is impacted by P input to soil and manure management practices that impact P transport processes. Twenty-one natural runoff plots were established to monitor the effect of time and method of composted beef feedlot manure application and feed P input on net losses of bio-available P and sediment in surface runoff. Reducing feed P inputs resulted in a 33% reduction in manure P content. Runoff losses of …

Cognition As An Independent Variable: Virtual Ecology, Alan C. Kamil, Alan B. Bond

Papers in Behavior in Biological Sciences

On close examination, human cultural artifacts bear the unmistakable impress of the structure of the human mind: our tools, habitations. and methods of communication have been molded to suit the strengths and limitations of the human cognitive system (Nosman 1988). It has not commonly been emphasized. however. that similar shaping processes have taken place over the course of biological evolution in response to the cognitive features of other, nonhuman species (Bonner 1980; von Frisch 1974).
Cognitive influences are particularly evident in the modifications of color patterns and behavior of prey species that take advantage of biases and constraints in the …

‘Neuroecologists’ Are Not Made Of Straw, Robert R. Hampton, Susan D. Healy, Sara J. Shettleworth, Alan Kamil

Papers in Behavior in Biological Sciences

In the October issue of Trends in Cognitive Sciences, Bolhuis and Macphail criticized the functional/evolutionary approach to the neural mechanisms of learning and memory, and concluded that the approach is ‘often misleading and might provide us with the wrong answers’ [1]. Their critique touches on a number of interesting issues, and provides a useful prompt to examine the role of an adaptationist approach to the study of cognition. In their effort to stimulate discussion, however, Bolhuis and Macphail have overstated positions they attribute to ‘neuroecologists’.

Spatial And Social Cognition In Corvids: An Evolutionary Approach, Russell P. Balda, Alan Kamil

Papers in Behavior in Biological Sciences

The central research questions that have guided our studies since 1981 combine issues and techniques from both comparative psychology and avian ecology. Most of our questions originate from the cognitive implications of extensive field studies on the natural history, ecology, and behavior of seed-caching corvids. Because our questions have evolved as our studies progressed, we have chosen to give a historical perspective outlining the progression of our ideas and questions.

Rabd, A Dictyostelium Rab14-Related Gtpase, Regulates Phagocytosis And Homotypic Phagosome And Lysosome Fusion, Ed Harris, James Cardelli

Department of Biochemistry: Faculty Publications

RabD, a Dictyostelium Rab14-related GTPase, localizes in the endo-lysosomal pathway and contractile vacuole system of membranes. Cell lines expressing dominant-negative RabD were defective in endocytosis, endosomal membrane flow and homotypic lysosome fusion. In support of a role for RabD in fusion, cells overexpressing constitutively active RabD^Q67L accumulated enlarged hydrolase-rich acidic vesicles ringed with GFP-RabD, consistent with RabD directly regulating lysosome fusion. To determine whether RabD also regulated phagocytosis and/or homotypic phagosome fusion (a process stimulated by many intracellular pathogens), cells overexpressing dominant-active (RabD^Q67L) or dominant-negative (Rab^N121I) RabD were analyzed microscopically and biochemically. The rate of …

Selenoprotein R Is A Zinc-Containing Stereo-Specific Methionine Sulfoxide Reductase, Gregory V. Kryukov, R. Abhilash Kumar, Ahmet Koc, Zhaohul Sun, Vadim N. Gladyshev

Department of Biochemistry: Faculty Publications

Selenoprotein R (SelR) is a mammalian selenocysteine-containing protein with no known function. Here we report that cysteine homologs of SelR are present in all organisms except certain parasites and hyperthermophiles, and this pattern of occurrence closely matches that of only one protein, peptide methionine sulfoxide reductase (MsrA). Moreover, in several genomes, SelR and MsrA genes are fused or clustered, and their expression patterns suggest a role of both proteins in protection against oxidative stress. Consistent with these computational screens, growth of Saccharomyces cerevisiae SelR and MsrA mutant strains was inhibited, and the strain lacking both genes could not grow, in …

Kinetic Properties Of Bifunctional 6-Phosphofructo-2-Kinase/Fructose-2,6-Bisphosphatase From Spinach Leaves, Jennifer E. Markham, Nicholas J. Kruger

Department of Biochemistry: Faculty Publications

A cDNA encoding 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase was isolated from a Spinacia oleracea leaf library and used to ex­press a recombinant enzyme in Escherichia coli and Spodoptera frugiperda cells. The insoluble protein expressed in E. coli was purified and used to raise antibodies. Western blot analysis of a protein extract from spinach leaf showed a single band of 90.8 kDa. Soluble protein was purified to homogeneity from S. frugiperda cells infected with recombinant baculovirus harboring the isolated cDNA. The soluble protein had a molecular mass of 320 kDa, estimated by gel filtration chromatography, and a subunit size of 90.8 kDa. The purified pro­tein …

Identification And Analysis Of A Conserved Immunoglobulin E-Binding Epitope In Soybean G1a And G2a And Peanut Ara H 3 Glycinins, Ping Ziang, Tom A. Beardslee, Michael G. Zeece, John P. Markwell, Gautam Sarath

Gautam Sarath Publications

To identify conserved immunoglobulin E (IgE)-binding epitopes among legume glycinins, we utilized recombinant soybean G2a and G2a-derived polypeptide fragments.

Purification And Characterization Of Acylation Stimulating Protein From Porcine Serum, Hong Zhang, Sheila K. Jacobi, Candace F. Toombs, Katherine H. Cianflone, Natalya Nersesian, Gautam Sarath, Jess L. Miner

Gautam Sarath Publications

A method for purifying acylation stimulating protein (ASP) from porcine serum is described. The mRNA encoding ASP was cloned by reverse transcriptase-polymerase chain reaction which predicted a 76 residue peptide. Based on this sequence, we generated antisera to a C-terminal peptide (ASP_1–20) which aided ASP purification. Identity of the purified protein was verified by N-terminal sequencing. The molecular mass of porcine ASP is 8926. Porcine ASP stimulated esterification of fatty acid into triacylglycerol in cultured human cells with potency similar to that of human ASP (twofold at 5 μM). Based on this evidence that ASP exists in porcine …

Uncertainties In Sediment Quality Weight-Of-Evidence (Woe) Assessments, Graeme E. Batley, G. Allen Burton, Peter M. Chapman, Valery E. Forbes

Valery Forbes Publications

Uncertainties in sediment quality assessments are discussed in five categories: (1) sediment sampling, transport and storage; (2) sediment chemistry; (3) ecotoxicology; (4) benthic community structure; and (5) data uncertainties and QA/QC. Three major exposure routes are considered: whole sediments, and waters in sediment pores and at the sediment-water interface. If these uncertainties are not recognized and addressed in the assessment process, then erroneous conclusions may result. Recommendations are provided for addressing the identified uncertainties in each of the key areas. The purpose of this paper is to improve the reporting of sediment quality assessments.

‘Neuroecologists’ Are Not Made Of Straw, Robert Hampton, Susan Healy, Sara Shettleworth, Alan C. Kamil

School of Biological Sciences: Faculty Publications

In the October issue of Trends in Cognitive Sciences, Bolhuis and Macphail criticized the functional/evolutionary approach to the neural mechanisms of learning and memory, and concluded that the approach is ‘often misleading and might provide us with the wrong answers’ [1]. Their critique touches on a number of interesting issues, and provides a useful prompt to examine the role of an adaptationist approach to the study of cognition. In their effort to stimulate discussion, however, Bolhuis and Macphail have overstated positions they attribute to ‘neuroecologists’.

Population Growth Rate As A Basis For Ecological Risk Assessment Of Toxic Chemicals, Valery E. Forbes, Peter Calow

Valery Forbes Publications

Assessing the ecological risks of toxic chemicals is most often based on individual-level responses such as survival, reproduction or growth. Such an approach raises the following questions with regard to translating these measured effects into likely impacts on natural populations. (i) To what extent do individual-level variables underestimate or overestimate population-level responses? (ii) How do toxicant-caused changes in individual-level variables translate into changes in population dynamics for species with different life cycles? (iii) To what extent are these relationships complicated by population-density effects? These issues go to the heart of the ecological relevance of ecotoxicology and we have addressed them …

Active Formation Of Mixed-Species Grouse Leks: A Role For Predation In Lek Evolution?, Robert M. Gibson

School of Biological Sciences: Faculty Publications

Behavioural ecologists have interpreted avian leks as products of sexual selection, in which males display socially to increase their opportunities to mate. However, without invoking reproductive queuing or kin selection, this paradigm does not necessarily explain why many males that fail to mate participate in leks. An alternative solution, that males also aggregate to reduce predation, has previously lacked compelling support. We show that mixed-species leks, comprising two congeneric grouse, form when single males or small groups of one species, the greater prairie chicken Tympanuchus cupido, join leks of another, the sharp-tailed grouse T. phasianellus. We documented the …

Active Formation Of Mixed-Species Grouse Leks: A Role For Predation In Lek Evolution?, Robert M. Gibson, Andrea S. Aspbury, Leonard L. Mcdaniel

School of Biological Sciences: Faculty Publications

Behavioral ecologists have interpreted avian leks as products of sexual selection, in which males display socially to increase their opportunities to mate. However, without invoking reproductive queuing or kin selection, this paradigm does not necessarily explain why many males that fail to mate participate in leks. An alternative solution, that males also aggregate to reduce predation, has previously lacked compelling support. We show that mixed-species leks, comprising two congeneric grouse, form when single males or small groups of one species, the greater prairie chicken Tympanuchus cupido, join leks of another, the sharp-tailed grouse T. phasianellus. We documented the …

Clone Size Of Andropogon Gerardii Vitman (Big Bluestem) At Konza Prairie, Kansas, Kathleen H. Keeler, Charles F. Williams, Linda S. Vescio

School of Biological Sciences: Faculty Publications

Clone size of plants of Andropogon gerardii from Konza Prairie Biological Station, Manhattan, Kansas was estimated from spatial patterns of genetic variation, using proteins detected by starch gel electrophoresis and DNA content (ploidy) measured by flow cytometry. Unique multi-locus protein banding patterns and differences in ploidy were used to exclude plants as members of the same clone. Individual clones averaged about 2 m in diameter and areas of prairie of 100 m² were calculated to contain an average of 31.8 genetic individuals.

Stability Of Mrna In The Hyperthermophilic Archaeon Sulfolobus Solfataricus, Elisabetta Bini, Vidula Dikshit, Kristi Dirksen, Melissa Drozda, Paul H. Blum

School of Biological Sciences: Faculty Publications

Archaea-like bacteria are prokaryotes but, in contrast, use eukaryotic-like systems for key aspects of DNA, RNA, and protein metabolism. mRNA is typically unstable in bacteria and stable in eukaryotes, but little information is available about mRNA half-lives in archaea. Because archaea are generally insensitive to antibiotics, examination of mRNA stability in the hyperthermophile, Sulfolobus solfataricus, required the identification of transcription inhibitors for half-life determinations. An improved lacS promoter-dependent in vitro transcription system was used to assess inhibitor action. Efficient inhibitors were distinguished as blocking both lacSp transcription in vitro and the incorporation of ³H-uracil into bulk RNA in …

Life History Response Of Mediterranean Fruit Flies To Dietary Restriction, James R. Carey, Pablo Liedo, Lawrence G. Harshman, Ying Zhang, Hans-Georg Müller, Linda Partridge, Jane-Ling Wang

Lawrence G. Harshman Publications

The purpose of this study was to investigate medfly longevity and reproduction across a broad spectrum of diet restriction using a protocol similar to those applied in most rodent studies. Age-specific reproduction and age of death were monitored for 1,200 adult males and 1,200 females, each individually maintained on one of 12 diets from ad libitum to 30% of ad libitum. Diet was provided in a fixed volume of solution that was fully consumed each day, ensuring control of total nutrient consumption for every fly. Contrary to expectation and precedence, increased longevity was not observed at any level of …

Relating The Unique Sensory System Of Amblypygids To The Ecology And Behavior Of Phrynus Parvulus From Costa Rica (Arachnida, Amblypygi), Eileen Hebets

Eileen Hebets Publications

Abstract: While the unique sensory system and neuroanatomy of amblypygids suggest that olfaction is important in their lives, to date no behavioral data exist to support this suggestion. To gain insight into amblypygid ecology and behavior, an individual mark–recapture study was conducted on the Costa Rican amblypygid Phrynus parvulus. Within two 50 by 25 m plots, the distribution and movement patterns of individual amblypygids were recorded for over 2 months. A total of 88 adult individuals (60 males and 28 females) were marked, with an average 51% resighted. Females were resighted more frequently than males (75% females, 40% males). …

Food Pulses Increase Longevity And Induce Cyclical Egg Production In Mediterranean Fruit Flies, James R. Carey, Pablo Liedo, Lawrence G. Harshman, X. Liu, Hans-Georg Müller, Linda Partridge, Jane-Ling Wang

Lawrence G. Harshman Publications

1. Inasmuch as virtually all studies on mortality and reproduction in insects are conducted under conditions in which food availability is constant, little is known about the demographic response of insects to variable food environments. For example, it is not known if and to what extent the life expectancy of insects subjected to shortages of high-quality food will increase and/or whether this increase is associated with major decreases in lifetime reproduction.

2. Therefore cohorts of 100 individual female medflies were subjected to different sets of conditions of protein availability (interspersed with sugar-only diets) including ad libitum sugar-only (no protein), ad …

A Comparative Study Of Geometric Rule Learning By Nutcrackers (Nucifraga Columbiana), Pigeons (Columba Livia), And Jackdaws (Corvus Monedula ), Juli E. Jones, Elena Antoniadis, Sara J. Shettleworth, Alan Kamil

Papers in Behavior in Biological Sciences

Three avian species, a seed-caching corvid (Clark’s nutcrackers; Nucifraga columbiana), a non-seed-caching corvid (jackdaws; Corvus monedula), and a non-seed-caching columbid (pigeons; Columba livia), were tested for ability to learn to find a goal halfway between 2 landmarks when distance between the landmarks varied during training. All 3 species learned, but jackdaws took much longer than either pigeons or nutcrackers. The nutcrackers searched more accurately than either pigeons or jackdaws. Both nutcrackers and pigeons showed good transfer to novel landmark arrays in which interlandmark distances were novel, but inconclusive results were obtained from jackdaws. Species differences in this …

Arabidopsis Disrupted In Sqd2 Encoding Sulfolipid Synthase Is Impaired In Phosphate-Limited Growth, Bin Yu, Changcheng Xu, Christoph Benning

Bin Yu Publications

The sulfolipid sulfoquinovosyldiacylglycerol is one of the three nonphosphorous glycolipids that provide the bulk of the structural lipids in photosynthetic membranes of seed plants. Unlike the galactolipids, sulfolipid is anionic at physiological pH because of its 6-deoxy-6-sulfonate-glucose (sulfoquinovose) head group. The biosynthesis of this lipid proceeds in two steps: first, the assembly of UDP-sulfoquinovose from UDP-glucose and sulfite, and second, the transfer of the sulfoquinovose moiety from UDP-sulfoquinovose to diacylglycerol. The first reaction is catalyzed by the SQD1 protein in Arabidopsis. Here we describe the identification of the SQD2 gene of Arabidopsis.We propose that this gene encodes the …

The Pgp1 Mutant Locus Of Arabidopsis Encodes A Phosphatidylglycerolphosphate Synthase With Impaired Activity, Changcheng Xu, Heiko Härtel, Hajime Wada, Miki Hagio, Bin Yu, Chris Eakin, Christoph Benning

Bin Yu Publications

Phosphatidylglycerol is a ubiquitous phospholipid that is also present in the photosynthetic membranes of plants. Multiple independent lines of evidence suggest that this lipid plays a critical role for the proper function of photosynthetic membranes and cold acclimation. In eukaryotes, different subcellular compartments are competent for the biosynthesis of phosphatidylglycerol. Details on the plant-specific pathways in different organelles are scarce. Here, we describe a phosphatidylglycerol biosynthesis-deficient mutant of Arabidopsis, pgp1. The overall content of phosphatidylglycerol is reduced by 30%. This mutant carries a point mutation in the CDP-alcohol phosphotransferase motif of the phosphatidylglycerolphosphate synthase (EC 2.7.8.5) isoform encoded by …

Ecology And Host Specificity Of Laelapine Mites (Acari: Laelapidae) Of Small Mammals In An Atlantic Forest Area Of Brazil, Fernanda Martins-Hatano, Donald Gettinger, Helena G. Bergallo

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Mesostigmaticm ites of the Laelapinae Berlese, 1892 (Acari:Laelapidae) are nidicolous arthropods that commonly occur in the fur of Neotropical small mammmals. In this 2-yr study, the laelapine acarofauna associated with the small mammal community in an area of Atlantic forest on Ilha Grande, Rio de Janeiro State, was examined, including observations on patterns of host specificity, mite dispersal, ecology, and food habits. A total of 1,347 laelapines was sampled from the pelage of 6 species of small mammals( Marmosops incanus, Nectomyss quamipes, Oryzomys russatus, Rhipidomys n. sp., Oxymycterus dasytrichus, and Trinomys dimidiatus), all of which occurred exclusively in …