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Measuring Shrubland Vegetational Structure Using Avian Habitats As An Example, Douglas A. James Jan 1992

Measuring Shrubland Vegetational Structure Using Avian Habitats As An Example, Douglas A. James

Journal of the Arkansas Academy of Science

Vegetational sampling of avian habitats stresses the use of methods primarily designed for forest birds. This paper describes a technique for sampling vegetational structure in uneven patchy habitats such as shrublands. Using the method, avian habitats in old field shrublands of northwestern Arkansas were analyzed.


Biological Vectors For The Dispersal Of Colletotrichum Gloeosporioides, X. B. Yang, D. O. Tebeest, E. L. Moore Jan 1992

Biological Vectors For The Dispersal Of Colletotrichum Gloeosporioides, X. B. Yang, D. O. Tebeest, E. L. Moore

Journal of the Arkansas Academy of Science

Green treefrogs (Hyla cinerea) and grasshoppers (Melanoplus differentialis and Conocephalus fasciatus) commonly observed in Arkansas rice fields, are dispersal vectors for Colletotrichum gloeosporioides f. sp. aeschynomens, a causal agent of anthracnose of northern jointvetch. Treefrogs and grasshoppers captured from rice or soybean fields with diseased northern jointvetch were placed in containers in contact with healthy northern jointvetch plants. An average of 90% of northern jointvetch plants was infected by the pathogen with up to 10 lesions per plant using treefrog vectors. Experiments were done in the greenhouse on frog dispersal by monitoring disease development from a point source in closed …


New Records Of Vertebrates In Southwestern Arkansas, C. Renn Tumlison, Mark R. Karnes, Mark E. Clark Jan 1992

New Records Of Vertebrates In Southwestern Arkansas, C. Renn Tumlison, Mark R. Karnes, Mark E. Clark

Journal of the Arkansas Academy of Science

No abstract provided.


Key To Subject Areas, Stephen L. Wood, Donald E. Bright Jr. Jan 1992

Key To Subject Areas, Stephen L. Wood, Donald E. Bright Jr.

Great Basin Naturalist Memoirs

No abstract provided.


A Biosystematic Study Of Panus Conchatus (Basidiomycetes; Agaricales), James Edward Johnson Jan 1992

A Biosystematic Study Of Panus Conchatus (Basidiomycetes; Agaricales), James Edward Johnson

Masters Theses

As part of a biosystematic study of Panus conchatus (Bull.: Fr.) Fr., North American and European herbarium specimens from the Field Museum and the University of Michigan were examined and a description of the taxon prepared. Tissue and single spore isolates were obtained from basidiocarps collected in Illinois. Single and polyspore isolates were obtained from a collection made in Switzerland by R. H. Petersen. Culture mat analyses were completed on several media and the taxonomic value of cultural characters assessed. Based on this study, the identification of somatic cultures by cultural characteristics is unlikely. Single spore isolates from the Illinois …


Evaluation Of Puccinia Convolvuli (Pers.) Cast. As A Biological Control Of Calystegia Sepium (L.) R. Br., Jonathan C. Beener Jan 1992

Evaluation Of Puccinia Convolvuli (Pers.) Cast. As A Biological Control Of Calystegia Sepium (L.) R. Br., Jonathan C. Beener

Masters Theses

A rapid detached leaf assay technique was developed to test various pathogens for biological control of hedge bindweed (Calystegia sepium). Detached leaves with complete petiole were excised, surface sterilized in 70% ethanol, washed with sterile distilled water, and placed in sterile petri plates with sterile filter paper moistened with 5ml sterile distilled water. Media, leaf size, temperature and light duration were then tested for conditions that would optimize maximal leaf longevity. The best conditions derived were: 12/12 hrs. light, dark, period, 30°C, sterile distilled water medium and leaves of any size. Twenty-five isolates recovered from bindweed lesions were grown on …


Spontaneous Tetraploid Melons, Perry E. Nugent, Dennis T. Ray Jan 1992

Spontaneous Tetraploid Melons, Perry E. Nugent, Dennis T. Ray

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

Since 1968, three spontaneous 4x melons (Cucumis melo L.) plants were discovered in our field or greenhouse plantings. Two were found in the cultivar Planters Jumbo and one in the virescent marker C879-52. Each of these 4x plants had rounded cotyledons, shorter internodes, thicker stems and leaves, more hairs, and smaller fruits, with larger stem and blossom scars, than their 2x counterparts. Also, their flowers, pollen grains, stomates, and seeds were larger. The discovery of a 4x virescent plant in 1987 allows easier germplasm transfer between ploidy levels. Morphological characteristics of 2x and 4x melons will allow identification without …


Effects Of Weaning On Concentrations Of Inhibin In Follicular Fluid And Plasma Of Sows, W. E. Trout, J. H. Killen, R. K. Christenson, B. D. Schanbacher, J. J. Ford Jan 1992

Effects Of Weaning On Concentrations Of Inhibin In Follicular Fluid And Plasma Of Sows, W. E. Trout, J. H. Killen, R. K. Christenson, B. D. Schanbacher, J. J. Ford

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

Changes in plasma and follicular fluid concentrations of inhibin were examined in sows after weaning at 28-32 days post partum. From 0 to 48 h after weaning, inhibin concentrations were 200-300times higher in follicular fluid from small ( < 4 mm) and medium-large( ≥4 mm) follicles than in ovarian venous plasma. Inhibin concentrations increased in follicular fluid from medium-large follicles at 24 and 48 h after weaning; concentrations in ovarian venous plasma were positively correlated with the number of medium-large follicles (r= 0·40)and with ovarian venous plasma concentrations of oestradiol (r= 0·61).Blood samples were collected for 30 days from sows (n=6) that exhibited oestrus within 5 days after weaning and from sows (n=5) that remained anoestrous for 11 days after weaning. Plasma inhibin concentrations rose in oestrous and anoestrous sows by 12 h and continued to rise for 60 h after weaning. Plasma inhibin concentrations rose further and were higher at 3·5-4·5days after weaning in oestrous sows than in sows that remained anoestrous. After oestrus, plasma inhibin concentrations declined. At weaning, plasma concentrations of follicle-stimulating hormone (FSH) were higher in sows that subsequently exhibited oestrus than in sows that remained anoestrous. After weaning, plasma concentrations of FSH declined in both groups, reached a nadir at 2·5days, and increased gradually in anoestrous sows; oestrous sows exhibited an FSH surge at oestrus. Plasma FSH returned to preweaning concentrations in both groups of sows at Days 7-8.The results demonstrated dynamic changes in plasma concentrations of FSH and inhibin in sows after weaning; an inverse relationship of these, with the exception during the preovulatory surge of FSH, typifies the porcine oestrous cycle.


Status Of Platanthera Praeclara Sheviak & Bowles (Western Prairie Fringed Orchid) In The Platte River Valley In Nebraska From Hamilton To Garden Counties, Tanya E. Bray, Barbara L. Wilson Jan 1992

Status Of Platanthera Praeclara Sheviak & Bowles (Western Prairie Fringed Orchid) In The Platte River Valley In Nebraska From Hamilton To Garden Counties, Tanya E. Bray, Barbara L. Wilson

Biology Faculty Publications

During June and July, 1991, a search for western prairie fringed orchid was conducted in the Platte River Valley in central and west-central Nebraska. No orchids were found in the 370 sites surveyed. Factors which may contribute to the scarcity of this orchid in the area surveyed include drought conditions in the previous three years; habitat alteration by draining, ditching, herbicide application, mowing for hay, crop cultivation and planting of non-native species for hay fields; invasion of the area by trees; and the presence of alkaline soils in some areas


Celebrating Garden Genius : A Handbook To Selected Gardens By Charles F. Gillette, Charles F. Gillette Forum, W. John Hayden, Sheila M. Hayden Jan 1992

Celebrating Garden Genius : A Handbook To Selected Gardens By Charles F. Gillette, Charles F. Gillette Forum, W. John Hayden, Sheila M. Hayden

Bookshelf

Celebrating Garden Genius : A Handbook to Selected Gardens by Charles F. Gillette was created as part of the 1992 Charles F. Gillette Forum at The Lewis Ginter Botanical Garden in Richmond, Virginia. W. John Hayden, Professor of Biology at the University of Richmond, and Sheila Hayden, Biology Research Associate at the University of Richmond, served as editors of the handbook.

_________________________________________

Charles F. Gillette
(1886-1969)

Arriving in Richmond on November 9, 1911 —a dull, damp, dreary day—Charles F. Gillette began his career in the Southeast as "clerk of the record" for landscape architect Warren Manning, who, working with architects …


Synopsis Of The Genus Tropisternus (Coleoptera Hydrophilidae) In Arkansas, George L. Harp Jan 1992

Synopsis Of The Genus Tropisternus (Coleoptera Hydrophilidae) In Arkansas, George L. Harp

Journal of the Arkansas Academy of Science

No abstract provided.


Australian Genetic Resources Of Trifolium And Ornithopus Species, Richard Snowball, Kevin Foster, Bill Collins Jan 1992

Australian Genetic Resources Of Trifolium And Ornithopus Species, Richard Snowball, Kevin Foster, Bill Collins

Journal of the Department of Agriculture, Western Australia, Series 4

The introduction of improved pasture legumes into the cereal growing areas of southern Australia changed the face of our agricultural systems.

Subterranean clover was the first pasture legume to have a major impact, and the first varieties were available commercially in the 1930s. Since then, many varieties have been released, leading to the most recent release of Denmark, Gou/bum and Leura in 1992.

The development of burr, barrel and murex medics also had an impact on the pasture production of less acid heavy soils. Yellow serradella is still being developed for the more acid sandy soils.

This development of improved …


New Leaf Rust Helps To Control Blackberry, Jonathon Dodd, Sandy Lloyd Jan 1992

New Leaf Rust Helps To Control Blackberry, Jonathon Dodd, Sandy Lloyd

Journal of the Department of Agriculture, Western Australia, Series 4

The release of spores of the blackbeny leaf rust in spring 1991 marked the second attempt in Western Australia at controlling weedy blackberries with a biological agent. The strain of rust now being used is expected to be more effective than the one released in the 1980s.

This article describes the techniques used for rearing and releasing the fungus and illustrates the effects of the rust on blackbeny.


Wood, Bark, And Pith Anatomy Of Old World Species Of Ephedra And Summary For The Genus, Sherwin Carlquist Jan 1992

Wood, Bark, And Pith Anatomy Of Old World Species Of Ephedra And Summary For The Genus, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Quantitative and qualitative data are presented for wood anatomy of 35 collections representing 22 Old World species of Ephedra; the survey of bark and pith anatomy is based on some of these species. Character-state ranges similar to those of the New World species are reported, although more numerous species show vessel absence in latewood. Little diminution in vessel diameter or density occurs in latewood of the eight species that are scandant or sprawling. Helical thickenings or sculpture occur in vessels of about a third of the Old World species, but these thickenings are clearly related to pits, often not …


Methyl Jasmonate Inhibition Of Root Growth And Induction Of A Leaf Protein Are Decreased In An Arabidopsis Thaliana Mutant, Paul E. Staswick, Wenpei Su, Stephen H. Howell Jan 1992

Methyl Jasmonate Inhibition Of Root Growth And Induction Of A Leaf Protein Are Decreased In An Arabidopsis Thaliana Mutant, Paul E. Staswick, Wenpei Su, Stephen H. Howell

Department of Agronomy and Horticulture: Faculty Publications

Jasmonic acid and its methyl ester, methyl jasmonate (MeJA), are plant signaling molecules that affect plant growth and gene expression. Primary root growth of wild-type Arabidopsis thaliana seedlings was inhibited 50% when seedlings were grown on agar medium containing 0.1 μM MeJA. An ethyl methanesulfonate mutant (jar1) with decreased sensitivity to MeJA inhibition of root elongation was isolated and characterized. Genetic data indicated the trait was recessive and controlled by a single Mendelian factor. MeJA induced polypeptides were detected in Arabidopsis leaves by antiserum to a MeJA-inducible vegetative storage protein from soybean. The induction of these proteins by …


New Diets For Production Of House Flies And Stable Flies (Diptera: Muscidae) In The Laboratory, Jerome Hogsette Jan 1992

New Diets For Production Of House Flies And Stable Flies (Diptera: Muscidae) In The Laboratory, Jerome Hogsette

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

A diet for rearing the house fly, Musca domestica (L.), was developed from feed constituents available on a year-round basis in Gainesville, FL. The diet, called the Gainesville House Fly Diet, performed as well or better than the Chemical Specialties Manufacturers' Association fly larval medium (CSMA) and can be mixed, bagged, and delivered by a local feed mill within 3 d. By adding pelleted peanut hulls 1:1 by volume, the house fly diet becomes suitable for rearing the stable fly, Stomoxys calcitrans (L.). Use of these diets and the economics involved are discussed further.


On The Trail Of The Native Budworm, Kevin Walden Jan 1992

On The Trail Of The Native Budworm, Kevin Walden

Journal of the Department of Agriculture, Western Australia, Series 4

Native budworm, the worst pest of lupins, is a bit of a uiill-o-the-unsp. Some years the native budworm moths go virtually unnoticed. In others, they appear in plague proportions without warning - in these years, the cost to growers in lost yield runs into millions of dollars.

If an early warning system can be developed to predict the extent of moth flights into lupin crops, and this seems possible, major crop losses could be averted.

The Department of Agriculture has started research to develop a system of predicting the size of spring flights of native budworm moth. We need to …


Clearwing Moths Are Key To Dock Control, Kingsley Fisher Jan 1992

Clearwing Moths Are Key To Dock Control, Kingsley Fisher

Journal of the Department of Agriculture, Western Australia, Series 4

Two clearwing moths imported from Morocco and France could be the key to controlling dock (Rumex pulcher) - one of the worst weeds of high rainfall pastures in southern Australia


Jasmonate, Genes, And Fragrant Signals, Paul E. Staswick Jan 1992

Jasmonate, Genes, And Fragrant Signals, Paul E. Staswick

Department of Agronomy and Horticulture: Faculty Publications

Although first recognized for its growth-inhibiting activity about 20 years ago, JA2 and its fragrant methyl ester MeJA (referred to here collectively as jasmonate) are receiving renewed interest as potentially important signaling molecules in plants. This is because jasmonate markedly increases the expression of specific plant genes, some of which are wound responsive. Similarities with fatty acid-derived stress signaling molecules in animals (1) make jasmonate of general biological interest.


Local Polyploid Variation In The Native Prairie Grass Andropogon Gerardii, Kathleen H. Keeler Jan 1992

Local Polyploid Variation In The Native Prairie Grass Andropogon Gerardii, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

The microscale distribution of polyploid variants of the dominant grass big bluestem (Andropogon gerardii) in virgin tallgrass prairie was mapped using flow cytometry. The correlation between DNA content and polyploidy allows the use of flow cytometry for nondestructive determination of polyploidy in intact plants. At Konza Prairie, local plots contained from 0 to 100% hexaploid cytotypes but most showed fine-scale mixing of the polyploid variants. The relationship of cytotype frequency to moisture availability or burning history was nonsignificant


Autoseparation Method For Harvesting House Fly (Diptera: Muscidae) Pupae Of Known Age, Jerome Hogsette Jan 1992

Autoseparation Method For Harvesting House Fly (Diptera: Muscidae) Pupae Of Known Age, Jerome Hogsette

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

Postfeeding larvae of Musca domestica (L.) were allowed to crawl from the larval rearing medium into sand-filled collection containers to pupate. By separating postfeeding larvae and pupae from the sand at predetermined intervals, the approximate time of pupation and the pupal age could be determined. More postfeeding larvae were collected in fine, wet sand than in coarse, dryer sand. Whether or not the sand was tightly packed into collection containers was unimportant, and fly mortality was not increased by the sand-collection method. Uses for the system and implications of the results are discussed.


Comparison Of Restriction Fragment Length Polymorphisms In Chloroplast Dna Of Five Leafy Spurge (Euphorbia Spp.) Accessions, Scott Nissen, Robert A. Masters, Donald Lee, Martha Rowe Jan 1992

Comparison Of Restriction Fragment Length Polymorphisms In Chloroplast Dna Of Five Leafy Spurge (Euphorbia Spp.) Accessions, Scott Nissen, Robert A. Masters, Donald Lee, Martha Rowe

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

Chloroplast DNA (cpDNA) restriction fragment length polymorphisms (RFLPs) were analyzed to assess genetic variation and relatedness among selections of North American and Eurasian leafy spurge. Leafy spurge accessions from Nebraska, Montana, Russia, Italy, and Austria were evaluated. Total DNA was extracted from young leaves and digested with the restriction endonuclease, EcoRI. CpDNA fragment patterns were determined by Southern blot analysis using mung bean cpDNA probes. Colinearity between the mung bean and leafy spurge chloroplast genomes was indicated by the observation that common fragments were hybridized by adjacent probes. Minimum estimates of chloroplast genome size for the five leafy spurge …


Introduction (English, French, German, And Spanish), Stephen L. Wood, Donald E. Bright Jr. Jan 1992

Introduction (English, French, German, And Spanish), Stephen L. Wood, Donald E. Bright Jr.

Great Basin Naturalist Memoirs

No abstract provided.


Supplement To The 1987 Bibliography, Stephen L. Wood, Donald E. Bright Jr. Jan 1992

Supplement To The 1987 Bibliography, Stephen L. Wood, Donald E. Bright Jr.

Great Basin Naturalist Memoirs

No abstract provided.


Distribution Of Foraminifera And Pollen In Coastal Depositional Environments Of The Southern Delmarva Peninsula, Virginia, U.S.A., Han Jun Woo Jan 1992

Distribution Of Foraminifera And Pollen In Coastal Depositional Environments Of The Southern Delmarva Peninsula, Virginia, U.S.A., Han Jun Woo

OES Theses and Dissertations

The coastal zone of the southern Delmarva Peninsula exhibits a wide variety of barrier island system subenvironments. This study investigates whether 20 a priori subenvironments can be distinguished from each other on the basis of abiotic environmental variables, pollen assemblages, living foraminiferal populations, and total (living plus dead) foraminiferal assemblages.

The physical data collected from the coastal zone were subjected to canonical variate analysis which discriminated 83% of the stations in 19 groups. These groups were clustered into two internally overlapping sets which represented the inside and outside of the inlet.

Twenty-two pollen types were found in low-energy marsh and …


Distribution, Habitats, And Taxonomy Of Ruppia Maritima L. And R. Occidentalis S. Watson In Nebraska, Robert B. Kaul Jan 1992

Distribution, Habitats, And Taxonomy Of Ruppia Maritima L. And R. Occidentalis S. Watson In Nebraska, Robert B. Kaul

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Specimens of Ruppia from all eleven Nebraska counties in which it is known fall into two groups: R. occidentalis in alkaline Sandhills waters and R. maritima in saline waters of the Platte River Valley and Lancaster County. Ruppia occidentalis is distinguished by its more robust size; redspotted leaves and stems; terete, entire, obtuse leaves; 4-8(9) carpels; and by two elliptic white spots on its endocarp, among other characteristics. Ruppia maritima is more delicate and unspotted; the leaves are oblate in section, sub-apically denticulate, and acute-acuminate; the carpels are 3 or 4, and the endocarp spots are nearly circular. Both species …


The Prairie Naturalist Volume 23, No. 4. December 1991 Dec 1991

The Prairie Naturalist Volume 23, No. 4. December 1991

The Prairie Naturalist

Paul B. Kannowski, Editor

Nikki R. Seabloom, Assistant Editor

Douglas H. Johnson, Book Review Editor

CONTENTS

KENTUCKY BLUEGRASS RESPONSE TO BURNING: INTERACTIONS BETWEEN FIRE AND SOIL MOISTURE ▪ G. W. Blankespoor and B. S. Bich

FORAGE PRODUCTION AND USE ON BIGHORN SHEEP WINTER RANGE

FOLLOWING SPRING BURNING IN GRASSLAND AND PONDEROSA PINE HABITATS ▪ T. G. Easterly and K. J. Jenkins

SHORT-TERM MORTALITY OF SMALLMOUTH BASS CAUGHT DURING A LIVE-RELEASE TOURNAMENT AT LAKE OAHE, SOUTH DAKOTA ▪ J. J. Jackson and D. W. Willis

CRAYFISH IN SAND LAKE NATIONAL WILDLIFE REFUGE ▪ C. D. Dieter

PIPING PLOVERS NEST ON DRY …


Viruses And Virus-Like Particles Of Eukaryotic Algae, James L. Van Etten, Leslie C. Lane, Russel H. Meints Dec 1991

Viruses And Virus-Like Particles Of Eukaryotic Algae, James L. Van Etten, Leslie C. Lane, Russel H. Meints

Department of Plant Pathology: Faculty Publications

TABLE OF CONTENTS:
INTRODUCTION
CHARACTERISTICS OF CHLORELLA SPECIES
General Properties of Chlorella Species
Symbiotic Chlorella Species
Chlorella Strains NC64A, Nla, Pbi, and SAG-241-80
DISCOVERY OF CHLORELLA VIRUSES
Initial Observations
Development of a Culturable System for PBCV-1
PROPERTIES OF CHLORELLA VIRUSES
General Characteristics of PBCV-1
Composition of PBCV-1
PBCV-1 Genome
Serology of PBCV-1
Additional Chlorella Strain NC64A Viruses
Viruses Infecting Chlorella Strain Pbi
REPLICATION OF PBCV-1
Attachment of PBCV-1 to Chlorella Strain NC64A
Intracellular Site of PBCV-1 Replication
Effect of PBCV-1 Infection on Host DNA, RNA, and Protein Syntheses
TRANSCRIPTION OF PBCV-1
VIRUSES ENCODE DNA METHYLTRANSFERASES AND DNA SITE-SPECIFIC (RESTRICTION) ENDONUCLEASES …


A Review Of Plant Introductions To The Kimberley 1955 To 1987, R Mccartney Nov 1991

A Review Of Plant Introductions To The Kimberley 1955 To 1987, R Mccartney

Grain and other field crops published reports

This report summarizes the work done by the Department of Agriculture, Western Australia, in the west and north Kimberley in introducing plant species during 1955-1987.

For the purposes of this repor1the following areas are defined thus:

• West Kimberley- lies between latitude 17°5 and 19°5 and longitude 121°E and 127°E, with an extension to the north of 1° between 121°E and I 24°20'E. The area is 118,000 km".

• North Kimberley - lies north of latitude 17°5 and between longitude 124°20'E and 127°30'E. The area is 85,000 km'.

• East Kimberley-lies north of latitude 19°5 and between longitude 127°30'E and …


Nebline, October 1991 Oct 1991

Nebline, October 1991

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Ag Update: Agricultural News & Events

Home Extension News

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