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Macroscopic And Microscopic Responses Of Gossypium Hirsutum L. To Hydrogen Fluoride Fumigation, Dan Timmermann Jr., Howard G. Applegate, E. Mark Engleman Jan 1970

Macroscopic And Microscopic Responses Of Gossypium Hirsutum L. To Hydrogen Fluoride Fumigation, Dan Timmermann Jr., Howard G. Applegate, E. Mark Engleman

Journal of the Arkansas Academy of Science

No abstract provided.


Impact Of Resistance To Pesticides On Cotton Insect Problems In Arkansas, Charles Lincoln, Jacob R. Phillips Jan 1970

Impact Of Resistance To Pesticides On Cotton Insect Problems In Arkansas, Charles Lincoln, Jacob R. Phillips

Journal of the Arkansas Academy of Science

No abstract provided.


Progress In Research On Noxious Weeds, Geoffrey A. Pearce Jan 1970

Progress In Research On Noxious Weeds, Geoffrey A. Pearce

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

RESEARCH on noxious weeds has enabled the development of many practical methods for the control of these weeds.

Where the recommended treatments have been accepted by farmers, large scale operations have reduced the areas infested and stopped spread into new paddocks.


Establishing Pastures Under Wheat Crops, M L. Poole, J. W. Gartrell, D. A. N. Nicholas Jan 1970

Establishing Pastures Under Wheat Crops, M L. Poole, J. W. Gartrell, D. A. N. Nicholas

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

RECENT surveys indicate that in the medium and high rainfall cereal and sheep areas as much as half the new pasture sown is sown with a crop.

In the drier wheatbelt areas the figure is 20 to 30 per cent.


Chemical Thinning Controls Biennial Bearing In Apples, J E L Cripps Jan 1970

Chemical Thinning Controls Biennial Bearing In Apples, J E L Cripps

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

Department of Agriculture experiments have shown that biennial bearing of apples can be controlled by chemical thinning, but both winter and spring weather conditions must be taken into account when the need for spraying is assessed.

BIENNIAL BEARING is a regular cycle in which each heavy crop of fruit is followed by a light crop, or, in extreme cases, no crop at all.


Identification Of Seeds Of Undesirable Weeds, J R. Peirce Jan 1970

Identification Of Seeds Of Undesirable Weeds, J R. Peirce

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

PREVENTING the introduction of weeds to a farm is a far cheaper proposition compared to the expensive and laborious process of eradicating a well established infestation.

Unfortunately most weeds establish themselves as plants before they are identified, the main reason being farmers are often unable to recognise weeds in the seed stage.


The Making Of A New Pasture Variety, Department Of Agriculture, Western Australia Jan 1970

The Making Of A New Pasture Variety, Department Of Agriculture, Western Australia

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

FARMERS who attend field days at Department of Agriculture research stations are reasonably familiar with the procedure for producing a new cereal variety. It involves a painstaking and tedious process of crossing, followed by many years of segregation, selection and testing for yield, disease resistance, and other characters.

Although there are many pitfalls, the procedure for the creation of a new cereal variety is at least fairly well systematised.

Until recently the making of a new pasture variety was far from a systematic undertaking.


Protein Synthesis During Fungal Spore Germination. Iv. Transfer Ribonucleic Acid From Germinated And Ungerminated Spores, James L. Van Etten, R. Kent Koski, Mahmoud El-Olemy Dec 1969

Protein Synthesis During Fungal Spore Germination. Iv. Transfer Ribonucleic Acid From Germinated And Ungerminated Spores, James L. Van Etten, R. Kent Koski, Mahmoud El-Olemy

Department of Plant Pathology: Faculty Publications

Transfer ribonucleic acid (tRNA) fractions isolated from germinated and ungerminated spores of Botryodiplodia theobromae and Rhizopus stolonifer had acceptor activity for all 20 amino acids commonly found in protein, when tested with an enzyme fraction from germinated spores. Accordingly, it is unlikely that the absence of tRNA for a particular amino acid limits protein synthesis in fungal spores.


Hatching Of Sod Webworm Eggs In Relation To Low Temperatures, E. A. Heinrichs, Ellis L. Matheny Dec 1969

Hatching Of Sod Webworm Eggs In Relation To Low Temperatures, E. A. Heinrichs, Ellis L. Matheny

Department of Entomology: Faculty Publications

Eggs of Chrysoteuchia topiaria (Zeller), Crambus pascuellus floridus (Zeller), and Pediasia trisecta (Walker) were exposed to temperatures of 25, 15, 10, 4, and –10°C. Only those of P. trisecta hatched after exposure to 4°C for 30 days, while none hatched after exposure to –10°C. Eggs of none of the species hatched after exposure to 4 and 10°C for 60 days. Pre-exposure and post-exposure conditioning had no significant effect on percent hatch of P. trisecta eggs, while length of exposure period had a significant effect.


Sweetclover Weevil Feeding Stimulants: Isolation And Identification Of Glucose, Fructose, And Sucrose, W. R. Akeson, H. J. Gorz, Francis A. Haskins Dec 1969

Sweetclover Weevil Feeding Stimulants: Isolation And Identification Of Glucose, Fructose, And Sucrose, W. R. Akeson, H. J. Gorz, Francis A. Haskins

Department of Agronomy and Horticulture: Faculty Publications

The water-soluble fraction of Melilotus leaves previously referred to as Stimulant A was further fractionated by preparative paper chromatography into three factors, each having a stimulatory effect on sweetclover weevil feeding. The three factors, designated Stimulant A1, A2, and A3, were identified as sucrose, glucose, and fructose, respectively, by co-chromatography with known sugars on cellulose-coated thin-layer plates. Silver nitrate, anisidine phthalate, and anthrone were employed as detection agents. The isolated compounds and corresponding reagent grade sugars were identical in chromatographic and chemical behavior, as well as in feeding stimulant activity. Sucrose stimulated the greatest …


Front Matter, Vol. 10 No. 4 Oct 1969

Front Matter, Vol. 10 No. 4

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


End Matter, Vol. 10 No. 4 Oct 1969

End Matter, Vol. 10 No. 4

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Nesting Ecology Of Raptorial Birds In Central Utah, Joseph R. Murphy, Franz J. Camenzind, Dwight G. Smith, J. Bradford Weston Oct 1969

Nesting Ecology Of Raptorial Birds In Central Utah, Joseph R. Murphy, Franz J. Camenzind, Dwight G. Smith, J. Bradford Weston

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Characterization Of Xanthomonas Phaseoli Bacteriophages, Anne K. Vidaver, Max L. Schuster Sep 1969

Characterization Of Xanthomonas Phaseoli Bacteriophages, Anne K. Vidaver, Max L. Schuster

Department of Plant Pathology: Faculty Publications

Ten bacteriophages for Xanthomonas phaseoli were characterized. On the basis of adsorption rates, latent period and burst size, plaque morphology, host range, efficiency of plating, ultrastructure, sensitivity to osmotic shock, streptomycin sensitivity, temperature effects on plating efficiency, and serology, the phages were separated into at least three groups. Some of the phages were infectious for Pseudomonas phaseolicola (four strains) and P. syringae (one strain) in a narrow temperature range. The taxonomic and ecological significance of this finding is discussed.


Morphology And Development Of The Flowers Of Boottia Cordata, Ottelia Alismoides, And Their Synthetic Hybrid (Hydrocharitaceae), Robert B. Kaul Sep 1969

Morphology And Development Of The Flowers Of Boottia Cordata, Ottelia Alismoides, And Their Synthetic Hybrid (Hydrocharitaceae), Robert B. Kaul

School of Biological Sciences: Faculty Publications

The inferior ovary of Boottia cordata, Ottelia alismoides, and their hybrid is appendicular in nature, the carpels are congenitally only slightly connate, and they are unsealed. All floral organs except the sepals originate from common primordia in the female and bisexual flowers. A flat residual floral apex is present. There is a vestigial superior ovary of three ontogeneticallv fused carpels in the male flower of Boottia cordata. The hybrid is intermediate in many characteristics and has partially fertile stamens and staminodia. The sequence of development in all flowers is acropetal. These plants appear to be related to …


The Effect Of Two Growth Retardant Chemicals, Cycocel And B-Nine, On Certain Nitrogeneous Components In Barley Seedlings, Linda Kinser Aug 1969

The Effect Of Two Growth Retardant Chemicals, Cycocel And B-Nine, On Certain Nitrogeneous Components In Barley Seedlings, Linda Kinser

Masters Theses & Specialist Projects

Certain chemicals are known to inhibit growth in many plant species. These chemicals possess a common trait, the ability to inhibit stem elongation by suppressing the activity of the subapical meristematic region (11). These growth retardants have been extensively studied during the past several years in an effort to determine the biochemical mechanism responsible for reduction in plant height. The characteristic effect of these chemical retardants on the growth pattern has been described as producing plants with shorter, thicker stems and broader, darker green leaves. Tolbert, however, noted that although plants treated with the plant growth retardant, Cycocel, (2-chloroethyltrimethlammoniumchloride) and …


An Investigation Of A Mycorrhizal Association On Opuntia Polyacantha, R. Craig Stutz Aug 1969

An Investigation Of A Mycorrhizal Association On Opuntia Polyacantha, R. Craig Stutz

Theses and Dissertations

Roots of Opuntia, polyacantha Haw. from Juab County, Utah were found to be nodulated. An anatomical study of the nodulated roots showed them to be ectotrophic mycorrhizae. Fusarium poae (Peck) Wollenweaver was found associated with the nodules both as an epiphyte and an endophyte. However, reinfection with this organism failed to induce subsequent nodulation. Under certain conditions the roots of o. polyacantha are able to overcome the mycorrhizal infection and elongate. It is not uncommon for several branch roots to originate from a single nodule. It is suggested that the fungus-root association found in o. polyacantha represents an early stage …


The Effects Of Herbicides On Three Soil Inhabiting Blue Green Algal Species, Lee C. Darlington Aug 1969

The Effects Of Herbicides On Three Soil Inhabiting Blue Green Algal Species, Lee C. Darlington

All Master's Theses

The object of this study was to examine the effects of varying concentrations of 2, 4-D, Dalapon, and Tordon on the growth of several nitrogen-fixing blue-green algal species obtained from soil samples and grown under culture conditions in the laboratory.


Ultrastructural Investigations Of Tilletia Caries Teliospores, James Vincent Allen Aug 1969

Ultrastructural Investigations Of Tilletia Caries Teliospores, James Vincent Allen

Theses and Dissertations

The purpose of this study was to investigate the ultrastructure of Tilletia caries teliospores. Specimens were prepared for viewing in the electron microscope by freeze-etching and thin-sectioning techniques. Thin-sectioning techniques gave excellent results with the teliospore walls and the lipid bodies within the teliospore but failed to adequately fix the membranes and internal organelle systems. Micrographs of Tilletia caries teliospores prepared using thin-sectioning show three major wall layers and two partition wall layers and abundant lipid bodies. The freeze-etch method of spore preparation proved superior to the thin-sectioning used in this study to reveal the internal organelle systems of the …


Surface Characteristics Of Conidia From Monosporous Cultures Of Penicillium Digitatum And Aspergillus Nidulans Var. Echinulatus, Raymond Kunito Fuji Aug 1969

Surface Characteristics Of Conidia From Monosporous Cultures Of Penicillium Digitatum And Aspergillus Nidulans Var. Echinulatus, Raymond Kunito Fuji

Theses and Dissertations

The purpose of this investigation was to evaluate the possible taxonomic significance of the "rodlet" patterns and spore wall configurations of conidia from monosporous cultures of Penicillium digitatum Saccardo and Aspergillus nidulans Eidam var. echinulatus Fennell & Raper. Freeze-etching the conidiospores from single spore isolates of these fungi revealed that spore wall patterns and configurations vary much too greatly to be of taxonomic importance on the strain and subspecies level. Environmental factors and genetic influences are discussed as possible mechanisms causing the variations of the spore wall configurations. A membrane-like structure that covers the "rodlet" patterns and which hinders spore …


A Study Of Conifer Invasion Into Meadows Surrounding Small Lakes And Ponds In The Trial Lake Region Of The Western Uinta Mountains, David Harvey Firmage Aug 1969

A Study Of Conifer Invasion Into Meadows Surrounding Small Lakes And Ponds In The Trial Lake Region Of The Western Uinta Mountains, David Harvey Firmage

Theses and Dissertations

The object of this study was to determine whether or not Lodgepole pine is successfully invading meadows near ponds in the western Uinta Mountains as a preliminary step to the invasion of the Spruce-Fir climax forest. Line transects were established at three sites near Trial Lake extending from forest to wet meadow. Along these transects the soil was studied to determine percent organic matter, pH, depth to mineral soil, and texture. Also the depth of the water table was measured and the topography plotted. The age and size of the trees along the transect was determined, and the extent of …


Phylogenetic Relationships Of Purshia Tridentata And Cowania Mexicana, Stewart C. Sanderson Aug 1969

Phylogenetic Relationships Of Purshia Tridentata And Cowania Mexicana, Stewart C. Sanderson

Theses and Dissertations

Because of the greatly increased supply of genetic variation which it provides, introgression is of great importance in determining both the rate and the direction of evolution. Hybridization between the genera Cowania and Purshia provides an excellent model for demonstrating the various products which might be expected from introgression. The present study is an attempt to further investigate phylogenetic relationships of Cowania mexicana and Purshia tridentata by use of cytological and biochemical techniques.


New Records And Species Of Neotropical Bark Beetles (Scolytidae: Coleoptera), Stephen L. Wood Jun 1969

New Records And Species Of Neotropical Bark Beetles (Scolytidae: Coleoptera), Stephen L. Wood

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Front Matter, Vol. 10 No. 3 Jun 1969

Front Matter, Vol. 10 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


End Matter, Vol. 10 No. 3 Jun 1969

End Matter, Vol. 10 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


End Matter, Vol. 10 No. 2 Jun 1969

End Matter, Vol. 10 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Front Matter, Vol. 10 No. 2 Jun 1969

Front Matter, Vol. 10 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


A Study Of The Weevil Tribe Celeuthetini Of The Solomon Islands (Coleoptera: Curculionidae), Vasco M. Tanner Jun 1969

A Study Of The Weevil Tribe Celeuthetini Of The Solomon Islands (Coleoptera: Curculionidae), Vasco M. Tanner

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Foliage Production And Consumption In An Oak Forest, David A. Boyce Jun 1969

Foliage Production And Consumption In An Oak Forest, David A. Boyce

Masters Theses

No abstract provided.


A Comparative Survey Of Soil Microfungi From Three Vegetation Types In Cedar Valley, Utah, Brent T. Wahlquist May 1969

A Comparative Survey Of Soil Microfungi From Three Vegetation Types In Cedar Valley, Utah, Brent T. Wahlquist

Theses and Dissertations

Microfungi were isolated from soil samples by the soil plate method. Soil samples were collected at depths of 0-1", 1-4", and 4-8" both between and beneath the canopy of the dominant vegetation in stands of greasewood, sagebrush, and pinyon-juniper. Salinity, pH, and percent organic matter were measured for each soil sample. A total of 148 strains of fungi representing 141 species and 46 genera were isolated and identified from these alkaline soils, Few strains, including some Aspergilli, occurred only in the more saline greasewood soils, while many strains, including several Penicillia, occurred in both sagebrush and piny-on-juniper soils but were …