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The P23 Protein Of Citrus Tristeza Virus Controls Asymmetrical Rna Accumulation, Satyanarayana Tatineni, Siddarame Gowda, Maria A. Ayllon, Maria R. Albiach-Marti, Shailaja Rabindran, William O. Dawson Jan 2002

The P23 Protein Of Citrus Tristeza Virus Controls Asymmetrical Rna Accumulation, Satyanarayana Tatineni, Siddarame Gowda, Maria A. Ayllon, Maria R. Albiach-Marti, Shailaja Rabindran, William O. Dawson

Department of Plant Pathology: Faculty Publications

Citrus tristeza virus (CTV), a member of the Closteroviridae, has a 19.3-kb positive-stranded RNA genome that is organized into 12 open reading frames (ORFs) with the 10 3' genes expressed via a nested set of nine or ten 3'-coterminal subgenomic mRNAs (sgRNAs). Relatively large amounts of negative-stranded RNAs complementary to both genomic and sgRNAs accumulate in infected cells. As is characteristic of RNA viruses, wild-type CTV produced more positive than negative strands, with the plus-to-minus ratios of genomic and sgRNAs estimated at 10 to 20:1 and 40 to 50:1, respectively. However, a mutant with all of the 3' genes …

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Segregation Of Spermatozoa Within Sperm Storage Tubules Of Fowl And Turkey Hens, L. M. King, J. P. Brillard, M. R. Bakst, A. M. Donoghue Jan 2002

Segregation Of Spermatozoa Within Sperm Storage Tubules Of Fowl And Turkey Hens, L. M. King, J. P. Brillard, M. R. Bakst, A. M. Donoghue

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

In avian species, spermatozoa reside in the oviduct for prolonged periods in specialized structures known as sperm storage tubules, but little is known about the relative distribution of spermatozoa in these tubules after successive inseminations by different males. The staining efficacies of various fluorescent dyes for fowl and turkey spermatozoa were evaluated to investigate one proposed mechanism of sperm competition. Hens were then inseminated at different intervals with stained and unstained spermatozoa to observe the spatial distribution of spermatozoa within the storage tubules. Several novel fluorescent lipophilic tracers that successfully stain mammalian spermatozoa either did not stain fowl or turkey …

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Corn Yield Potential And Optimal Soil Productivity In Irrigated Corn/Soybean Systems, Achim R. Dobermann, Timothy J. Arkebauer, Kenneth G. Cassman, Rhae A. Drijber, J. Lindquist, S. Madhaven, John P. Markwell, Lenis Alton Nelson, James E. Specht, Daniel T. Walters, Haishun Yang, Brigid Amos, Darren L. Binder, C. Murphy, Gregory J. Teichmeier Jan 2002

Corn Yield Potential And Optimal Soil Productivity In Irrigated Corn/Soybean Systems, Achim R. Dobermann, Timothy J. Arkebauer, Kenneth G. Cassman, Rhae A. Drijber, J. Lindquist, S. Madhaven, John P. Markwell, Lenis Alton Nelson, James E. Specht, Daniel T. Walters, Haishun Yang, Brigid Amos, Darren L. Binder, C. Murphy, Gregory J. Teichmeier

Department of Agronomy and Horticulture: Faculty Publications

In 1999, an interdisciplinary research team at the University of Nebraska established a field experiment to (1) quantify and understand the yield potential of corn and soybean under irrigated conditions, (2) identify efficient crop management practices to achieve yields that approach potential levels, and (3) determine the energy use efficiency, global warming and soil C-sequestration potential of intensively managed corn systems. The experiment compares systems that represent different levels of management intensity expressed as combinations of crop rotation (continuous corn, corn-soybean), plant density (low, medium, high) and nutrient management (recommended best management vs. intensive management). Detailed measurements include soil nutrient …

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Crop Sequence And Nitrogen Fertilization Effects On Soil Properties In The Western Corn Belt, M. A. Liebig, Gary E. Varvel, John W. Doran, Brian J. Wienhold Jan 2002

Crop Sequence And Nitrogen Fertilization Effects On Soil Properties In The Western Corn Belt, M. A. Liebig, Gary E. Varvel, John W. Doran, Brian J. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Understanding long-term management effects on soil properties is necessary to determine the relative sustainability of cropping systems. Soil physical, chemical, and biological properties were measured in a long-term cropping system study in the Western Corn Belt. Properties were evaluated after 16 yr in four crop sequences [continuous corn (Zea mays L.) (CC), corn–soybean [Glycine max. (L.)] (C–SB), corn–oat (Avena sativa L.) + clover (80% sweet clover [Melilotus officinalis L.] and 20% red clover [Trifolium pratense L.])–grain sorghum [(Sorghum bicolor (L.) Moench)–soybean (C–OCL–SG– SB), and corn–soybean-grain sorghum–oat + clover (C–SB–SG– OCL)] each at three …

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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 Jan 2002

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 …

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Growth Response Of Velvetleaf To Three Postemergence Herbicides, Cheryl A. Murphy, John L. Lindquist Jan 2002

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 …

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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 Jan 2002

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 …

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Combinatorial Control Of Yeast Fet4 Gene Expression By Iron, Zinc, And Oxygen, Brian M. Waters, David J. Eide Jan 2002

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 …

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Kinetic Properties Of Bifunctional 6-Phosphofructo-2-Kinase/Fructose-2,6-Bisphosphatase From Spinach Leaves, Jennifer E. Markham, Nicholas J. Kruger Jan 2002

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 …

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Clone Size Of Andropogon Gerardii Vitman (Big Bluestem) At Konza Prairie, Kansas, Kathleen H. Keeler, Charles F. Williams, Linda S. Vescio Jan 2002

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.

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In Vitro Mutation Induction By Gamma Irradiation For The Improvement Of A Triploid Banana Pisang Berangan (Aaa), Shadia Aldelgadir Mohamed Rayis Jan 2002

In Vitro Mutation Induction By Gamma Irradiation For The Improvement Of A Triploid Banana Pisang Berangan (Aaa), Shadia Aldelgadir Mohamed Rayis

Student Works (2000-2009)

Tissue culture and induced mutation techniques were used to generate variation for the improvement of Pisang Bcrangan cv. 'Intan' (AAA). Best field perform ing banana in vitroplants were multiplied and evaluated for better field performance, which included improved agronomic traits such as earliness in fruiting, short plant stature, high yielding capacity with desirable fruit quality and tolerance to Fusarium wilt. A suitable micropropagation medium for Pisang Berangan was established through modification of MS basic medium, which resulted in significant increase in shoot multiplication. Shoot-tip meristems of Pisang Berangan were then irradiated at 20, 30, 40 and 60 Gy to induce …

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Repellency Of Ir3535, Kbr3023, Para-Menthane-3,8-Diol, And Deet To Black Salt Marsh Mosquitoes (Diptera: Culicidae) In The Everglades National Park, Donald R. Barnard, Ulrich R. Bernier, Kenneth H. Posey, Rui-De Xue Jan 2002

Repellency Of Ir3535, Kbr3023, Para-Menthane-3,8-Diol, And Deet To Black Salt Marsh Mosquitoes (Diptera: Culicidae) In The Everglades National Park, Donald R. Barnard, Ulrich R. Bernier, Kenneth H. Posey, Rui-De Xue

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

IR3535, KBR3023, para-menthane-3,8-diol (PMD), and deet were evaluated in controlled studies with human subjects (n = 5) for repellency to black salt marsh mosquitoes (Ochlerotatus taeniorhynchus Wiedemann), in the Everglades National Park, FL. In tests of 6-h duration, with an average mosquito biting pressure on exposed forearm skin of 19.5 (±13.7) bites per minute, the mean percent repellencies (SE) for IR3535, KBR3023, PMD, and deet was 88.6 (3.2), 97.5 (1.7), 89.2 (2.9), and 94.8 (2.5), respectively. Mean complete protection times (SE) for IR3535, KBR3023, PMD, and deet were 3.0 (1.0), 5.4 (0.6), 3.8 (1.4), and 5.6 (0.5) h, …

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Electrical Conductivity Monitoring Of Soil Condition And Available N With Animal Manure And A Cover Crop, R. A. Eigenberg, John W. Doran, John A. Nienaber, Richard B. Ferguson, B. L. Woodbury Jan 2002

Electrical Conductivity Monitoring Of Soil Condition And Available N With Animal Manure And A Cover Crop, R. A. Eigenberg, John W. Doran, John A. Nienaber, Richard B. Ferguson, B. L. Woodbury

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

Development of sustainable agricultural management systems will depend, in part, on the ability to better use renewable resources, such as animal manure, and to synchronize the levels of soil available N with crop plant needs during the growing season. This study was conducted at the US Meat Animal Research Center in the central USA to determine whether differences in electromagnetic (EM) soil conductivity and available N levels over a growing season can be linked to feedlot manure/compost application and use of a green winter cover crop. A series of soil conductivity maps of a research cornfield were generated using global …

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Reductions In Grassland Species Evenness Increase Dicot Seedling Invasion And Spittle Bug Infestation, Brian J. Wilsey, H. Wayne Polley Jan 2002

Reductions In Grassland Species Evenness Increase Dicot Seedling Invasion And Spittle Bug Infestation, Brian J. Wilsey, H. Wayne Polley

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

Previous experiments that tested whether diverse plant communities have lower invasibility have all varied species richness. We experimentally varied evenness of four grassland species (three grasses and one forb) by planting a field experiment in Texas, and monitored the number of unplanted dicot and monocot species that invaded plots for two growing seasons. By varying evenness, we eliminated any sampling effect in our diversity treatment, because all plots contained the same plant species. Experimentally reducing evenness led to a greater number of dicot invaders, which emerged in plots throughout the growing season, but had less of an effect on monocot …

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Oviducal Sperm Storage In Turkeys: Spatial Distribution Of Sperm Within The Uterovaginal Junction Sperm-Storage Tubules, M. R. Bakst, Bryan T. Vinyard Jan 2002

Oviducal Sperm Storage In Turkeys: Spatial Distribution Of Sperm Within The Uterovaginal Junction Sperm-Storage Tubules, M. R. Bakst, Bryan T. Vinyard

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

The spatial distribution of sperm within the sperm storage tubules (SST) found in
the uterovaginal junction (UVJ) of the turkey is not known. In this study, we inseminated sperm stained with a fluorescent dye (Hoechst 33342) to determine their distribution in SST in the ventral, dorsal, and lateral regions of the proximal, middle, and distal regions of the UVJ. There was no preferential filling in the ventral-dorsal axis of the UVJ. In contrast, preferential filling of the SST was observed in the middle section of the UVJ. Here the individual SST were clearly longer and more pleomorphic than the SST …

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Physiology And Reproduction: Embryonic Development From First Cleavage Through Seventy-Two Hours Incubation In Two Strains Of Pekin Duck (Anas Platyrhynchos), V. Dupuy, B. Nersessian, M. R. Bakst Jan 2002

Physiology And Reproduction: Embryonic Development From First Cleavage Through Seventy-Two Hours Incubation In Two Strains Of Pekin Duck (Anas Platyrhynchos), V. Dupuy, B. Nersessian, M. R. Bakst

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

Embryonic mortality is a significant problem plaguing the commercial duck industry worldwide. Yet, an objective means to stage development of the duck embryo is lacking. Such a staging procedure, which is described in this study, is essential for the critical and reproducible assessment of embryo development. The morphological features associated with duck embryo development are very similar to those of the chicken, although the duck embryo develops more slowly. The staging scheme presented here provides objective morphological criteria describing the embryonic development of the duck.

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Beet Armyworm (Lepidoptera: Noctuidae) Host Plant Preferences For Oviposition, S. M. Greenberg, T. W. Sappington, T.-X. Liu Jan 2002

Beet Armyworm (Lepidoptera: Noctuidae) Host Plant Preferences For Oviposition, S. M. Greenberg, T. W. Sappington, T.-X. Liu

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

Beet armyworm, Spodoptera exigua (Hübner), oviposition preferences were determined on five host plants: cabbage (Brassica oleracea capitata L.), cotton (Gossypium hirsutum L.), bell pepper (Capsicum annuum L.), pigweed (Amaranthus retroflexus L.), and sunflower (Helianthus annuus L.) in no-choice, two-choice, and five-choice tests. Tests were conducted in the laboratory, greenhouse, and field cages. Oviposition preferences were compared on the basis of two measurements, the proportion of eggs laid on the plants to total that were deposited, and the oviposition preference index defined as [(number of eggs laid on the plant) - (number of eggs laid on …

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Soil Electrical Conductivity Classification: A Basis For Site-Specific Management In Semiarid Cropping Systems, Cinthia K. Johnson, David A. Mortensen, Brian J. Wienhold, John F. Shanahan, John W. Doran Jan 2002

Soil Electrical Conductivity Classification: A Basis For Site-Specific Management In Semiarid Cropping Systems, Cinthia K. Johnson, David A. Mortensen, Brian J. Wienhold, John F. Shanahan, John W. Doran

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

Site specific management (SSM) has the potential to improve both economic and ecological outcomes in agriculture. Effective SSM requires strong and temporally consistent relationships between identified management zones, underlying soil physical, chemical and biological parameters defining yield potential, and crop yield. In a farm-scale (250 ha) experiment in semiarid northeastern Colorado, each of eight 31-ha fields was individually mapped for soil apparent electrical conductivity (ECa) and classified into four management zones (ranges of ECa). Soil analyses revealed a strong negative relationship between ECa zones and soil parameters associated with innate fertility (P ≤ 0.06). …

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Starter Fertilizer Effects On Soybean Grain Yield And Quality, S.L. Osborne, W.E Riedell, J.L. Pikul Jr Jan 2002

Starter Fertilizer Effects On Soybean Grain Yield And Quality, S.L. Osborne, W.E Riedell, J.L. Pikul Jr

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

Fertilizing soybeans (Glycine max (L.) Merrill) is not an entirely new concept; for a number of years, scientists have investigated the effect of nitrogen (N) fertilizer on yield and quality of soybeans. The objective of this research was to investigate the effect of starter fertilizer N rates and sources on soybean yield, protein, and oil content in the cool soils of the Northern Great Plains. A field experiment was established within a two-year corn (Zea mays L.) soybean rotation. Using a split-plot design with four replications. Whole plots were no-till (NT) and conventional tillage (CT) and the split …

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Tillage And Beef Cattle Manure Effects On Soil Nitrogen In A Dryland Rotation, R. C. Schwartz, R.L. Baumhardt, T.H. Dao Jan 2002

Tillage And Beef Cattle Manure Effects On Soil Nitrogen In A Dryland Rotation, R. C. Schwartz, R.L. Baumhardt, T.H. Dao

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

Minimum tillage practices used in dryland cropping systems that reduce soil water evaporation and erosion may also decrease efficiency of manure nutrient utilization. We initiated a study in 1997 to investigate the effects of surface-applied stockpiled and composted beef cattle (Bos taurus) manure on soil N and sorghum [Sorghum bicolor (L.) Moench] and wheat (Triticum aestivum L.) yields and N-uptake within a wheat-sorghum-fallow dryland crop rotation. Paired terraces with no-tillage (NT) and stubble-mulch tillage (ST) systems were main plots of a single rotation phase. Stockpiled manure, composted manure, or commercial fertilizer (urea + ammonium phosphate) were …

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Development Of Hydrotaea Aenescens (Diptera: Muscidae) In Manure Of Unweaned Dairy Calves And Lactating Cows, Jerome Hogsette, Robert Farkas, Reginald Coler Jan 2002

Development Of Hydrotaea Aenescens (Diptera: Muscidae) In Manure Of Unweaned Dairy Calves And Lactating Cows, Jerome Hogsette, Robert Farkas, Reginald Coler

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

In laboratory studies performed in the United States and Hungary, the dump fly Hydrotaea aenescens (Wiedemann) was reared successfully in manure of 1- to 8-wk-old dairy calves, and in manure from adult lactating dairy cows. Survival in manure collected from 1-wk-old calves was poor (7.2%), better in manure collected from 2- and 3-wk-old calves (53.5%), and best in manure collected from 4- to 8-wk-old calves (71.4%). Survival in cow manure was slightly lower (47.4%) than that in calf manure. Reasons for different rates of development in the United States and in Hungary, and by calf age are discussed as are …

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Thermal Death Kinetics And Heatingrate Effects For Fifth-Instar Cydia Pomonella (L.) (Lepidoptera: Tortricidae), S. Wang, J. N. Ikediala, J. Tang, J. D. Hansen Jan 2002

Thermal Death Kinetics And Heatingrate Effects For Fifth-Instar Cydia Pomonella (L.) (Lepidoptera: Tortricidae), S. Wang, J. N. Ikediala, J. Tang, J. D. Hansen

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

Thermal death kinetic parameters of fifth-instar codlingmoths (Cydia pomonella (L.)) and the effect of three heating rates (1°Cmin-1, 10°Cmin-1, and 18°Cmin-1) on larval mortality were determined by a heatingblock system. The insects were heated to four temperatures (46°C, 48°C, 50°C, and 52°C) held for predetermined periods followed by 24 h storage at 4°C before mortality evaluation. Thermal death kinetics for fifth-instar codlingmoths followed a 0.5th order of kinetic reaction. Minimum time required to achieve 100% mortality of a given population decreased with temperature in a semi-logarithmic manner. No larval survival was observed in …

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The Short Term Effects Of A Fire Fighting Foam And Fire Retardant On Selected Flora From Australia's Southwest, Andrew B. Kennedy Jan 2002

The Short Term Effects Of A Fire Fighting Foam And Fire Retardant On Selected Flora From Australia's Southwest, Andrew B. Kennedy

Theses : Honours

Chemical fire suppressants arc used extensively throughout Australia's Southwest to contain and suppress wildfires. Despite several studies being conducted into their effects on terrestrial vegetation in North America and Eastern Australia, where a variety of significant effects were found, no such investigation has been carried out in Australia's Southwest. This study examined the short-term effects of a fire fighting foam and fire retardant on selected flora from Australia's Southwest. Various concentrations of fire fighting foam and fire retardant were applied to seeds and seedlings of several native species. Native species were chosen for their high abundance and widespread distribution throughout …

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Invasion Of Indigenous Vegetation In South-Western Australia By Leptospermum Laevigatum (Gaertn.) F. Muell. (Myrtaceae), Anya Lam Jan 2002

Invasion Of Indigenous Vegetation In South-Western Australia By Leptospermum Laevigatum (Gaertn.) F. Muell. (Myrtaceae), Anya Lam

Theses : Honours

The current paradigm of biodiversity conservation requires the assessment of alien plant invaders, and their potential negative impacts on indigenous species and communities. Leptospermum laevigatum (Gaertn.) F. Muell. (Victorian tea tree/ Coast tea tree) is indigenous to eastern Australia. It has invaded ecosystems within its natural biogeographic range, within new ranges in Australia and overseas. The species is listed as a high priority weed in the Environmental Weed Strategy for Western Australia. However, the basis for its listing has been casual observation rather than focussed research. This study of L. laevigatum is unique in being the first to …

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Spatial And Temporal Patterns Of Eastern White Pine Regeneration In The Northwestern Ohio Oak Stand, Scott R. Abella, Neil W. Macdonald Jan 2002

Spatial And Temporal Patterns Of Eastern White Pine Regeneration In The Northwestern Ohio Oak Stand, Scott R. Abella, Neil W. Macdonald

Public Policy and Leadership Faculty Research

Eastern white pine (Pinus strobus L.) was often associated with oaks (Quercus spp.) on upland sites in presettlement forests of the upper Great Lakes region, but widespread logging and subsequent fires in the late 1800s converted these upland sites to fire-tolerant oak forests. Although white pine regeneration is occurring in these second-growth oak forests, white pine regeneration patterns in oak forests of the Great Lakes region are not well documented. We examined white pine regeneration in the southern Great Lakes region in an oak stand within the Oak Openings region of northwestern Ohio, where white pine plantations established in the …

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Creation Of Three Nutritional Mixes Based On Amaranth (Amaranthus Caudatus) And Other Andean Crops For School-Aged Children (Cochabamba-Bolivia), Sandra Carola Delgadillo Barriga Jan 2002

Creation Of Three Nutritional Mixes Based On Amaranth (Amaranthus Caudatus) And Other Andean Crops For School-Aged Children (Cochabamba-Bolivia), Sandra Carola Delgadillo Barriga

Theses and Dissertations

In Bolivia we have three very valuable Andean grains: amaranth (Amaranthus caudatus), quinoa (Chenopodium quinua), and canihua (Chenopodium pallidicaule), which combined with cereals and legumes can become a complete and balanced food in order to combat the malnutrition that is so widespread in our region. In this study, various nutritional mixes were formulated, based on amaranth and other Andean crops, and the three best were chosen according to nutrition, palatability, and cost. They were: Andean Baby Food, Mixicereal, and Amaranth Cookie, which have an amino acid complement between 79% and 100% and give satisfactory amounts of protein, energy, and minerals …

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Gas Exchange And Yields Of Bt Resistant Maize (Zea Mays L.) With European Corn Borer (Ostrinia Nubilalis, Hubner) Infestation, Shad Mallady Jan 2002

Gas Exchange And Yields Of Bt Resistant Maize (Zea Mays L.) With European Corn Borer (Ostrinia Nubilalis, Hubner) Infestation, Shad Mallady

Masters Theses

Seed companies have transgenic maize (Zea mays L.) hybrids resistant to European corn borer (ECB) [Ostrinia nubilalis (Hübner)]. However, the impact of this Bt (Bacillus thuringiensis) gene on other plant processes is not understood. In 1997 and 1999, a study at Central Golden Harvest Research in Clinton, IL focused on how the Bt gene affects gas exchange and yields of maize with and without ECB infestation. Bt and non-Bt isogenic pairs were planted with or without nets and/or insecticides to eliminate natural infestation of ECB, and with or without manual infestation of ECB. Photosynthesis and transpiration …

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Reproductive Biology Of Stylisma Pickeringii (Convolvulaceae), An Endangered Plant Of Illinois Sand Prairies, Brent L. Todd Jan 2002

Reproductive Biology Of Stylisma Pickeringii (Convolvulaceae), An Endangered Plant Of Illinois Sand Prairies, Brent L. Todd

Masters Theses

The sand prairie is a unique ecosystem in the state of Illinois, being the habitat for many interesting plants and animals not found elsewhere in the state. One such plant is the state-endangered Stylisma pickeringii (Torr. ex M.A. Curtis) Gray var. pattersoni (Fern. & Schub.) Myint (Convolvulaceae), also known as Patterson's bindweed or Patterson's dawn flower. It currently is found in only three Illinois counties—Cass, Henderson, and Mason. Presently, two of the three populations of S. pickeringii are located on private lands. Very little information is known about the reproductive biology of S. pickeringii var. pattersoni. Thus, the purpose of …

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Isoetes Toximontana (Isoetaceae), A New Quillwort With Green Megaspores From The Northern Cape Of South Africa, Lytton John Musselman, J. P. Roux Jan 2002

Isoetes Toximontana (Isoetaceae), A New Quillwort With Green Megaspores From The Northern Cape Of South Africa, Lytton John Musselman, J. P. Roux

Biological Sciences Faculty Publications

Isoetes toximontana is only the second quillwort reported from the Northern Cape region in South Africa. It occurs in shallow water on the Gifberg. Megaspores are uniformly tuberculate on the proximal surface; their distal surfaces may have occasional rugi along with bullae. They are olive green when dry. Microspores are brown and aculeate. Preliminary field studies suggest that an unexpected diversity of quillworts is found in this region.

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The Use Of Aflp To Detect Genetic Differentiation Within And Among Populations Of Two Prairie Plant Species: Panicum Virgatum And Coreopsis Palmata, Christopher Andrew Hilker Jan 2002

The Use Of Aflp To Detect Genetic Differentiation Within And Among Populations Of Two Prairie Plant Species: Panicum Virgatum And Coreopsis Palmata, Christopher Andrew Hilker

Dissertations and Theses @ UNI

The degree of genetic diversity within any species is crucial to its survival with respect to environmental stresses and its ability to adapt. As native Iowa prairie plant populations continues to diminish, genetic diversity within the state becomes crucially important for restoration, reconstruction, and conservation efforts. This study seeks to determine the degree of genetic variation within native Iowa populations of Panicum virgatum (switchgrass) and Coreopsis palmata (prairie coreopsis, tickseed, prairie tickseed). Plants were obtained directly from the tallgrass prairie, from native seed plantings, and from greenhouse grown cultivated varieties (switchgrass). Amplified Fragment Length Polymorphisms (AFLP) provided genetic fingerprints of …

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