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Influence Of Previous Liming, N And P Fertilization Of An Oxisol On Grain Yield In Navy Beans, H. O. Mongi, A. P. Uriyo Jul 1975

Influence Of Previous Liming, N And P Fertilization Of An Oxisol On Grain Yield In Navy Beans, H. O. Mongi, A. P. Uriyo

Tanzania Journal of Science

A field study was initiated towards the end of the 1973 rain season to assess some residual effects of lime, N and P applications to a moderately acid Oxisol (initial pH 5.6; LR 10 tons/ha) on grain yield in navy beans, Phaseolus vulgaris L., grown soon following maize silage. The Oxisol was a sandy clay loam (35:13:52). The design was a split-plot, confounded factorial with 4 levels of lime at 0, 7.5, 10.0 and 12.5 tons agricultural lime/ha; N at 0, 100, 200 and 300 kg N/ha as ammonium sulphate; and P at 0, 40, 80 and 120 kg P/ha …


A Preliminary Survey Of The Vascular Flora Of Upper Tygarts Creek, Carter County, Kentucky, William Michael Huffaker Jul 1975

A Preliminary Survey Of The Vascular Flora Of Upper Tygarts Creek, Carter County, Kentucky, William Michael Huffaker

Morehead State Theses and Dissertations

A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by William Michael Huffaker on July 23, 1975.


Two New Species Of The Genus Cycadeoidea From The Lower Cretaceous Of Utah, H. Blaine Furniss Jul 1975

Two New Species Of The Genus Cycadeoidea From The Lower Cretaceous Of Utah, H. Blaine Furniss

Theses and Dissertations

Cyadeoidea medullara and C. cleavelandii, two new species of the genus Cycadeoidea, have been recovered from the Lower Cretaceous Cedar Mountain Formation of Utah. They have been described in histologic detail and relationships with similar species are set forth. Monoecism and pollination mechanisms have been discussed in connection with C. medullara. This data contributes to our knowledge of the diverse composition of Lower Cretaceous floras in Utah.


A Paleocene Flora From The Fort Union Formation Near Baggs, Carbon County, Wyoming, John L. Roth Jul 1975

A Paleocene Flora From The Fort Union Formation Near Baggs, Carbon County, Wyoming, John L. Roth

Theses and Dissertations

A well-preserved Paleocene flora of 39 species from the Fort Union Formation near Baggs, Carbon County, Wyoming has been studied. This is the first study of the plant megafossils in this area. The most abundant species collected are: Carya antiquorum Platanus nobilis, Cercidiphyllum arcticum and Platanus raynoldsi. Together they represent 74% of the flora. The flora has been dated as Upper Middle Torrejonian. This report is also the first paleoecological study of any North American Paleocene flora. Two methods were used to determine the paleoclimatic conditions of the flora. The first was an analysis of leaf margin characteristics, comparing them …


Bulletin No. 21: Energy Conservation On The Home Grounds: The Role Of Naturalistic Landscaping, William A. Niering, Richard H. Goodwin Jul 1975

Bulletin No. 21: Energy Conservation On The Home Grounds: The Role Of Naturalistic Landscaping, William A. Niering, Richard H. Goodwin

Bulletins

No abstract provided.


The Subfamily Leeuwenhoekinae In The Neotropics (Acarina: Trombiculidae), Jack T. Reed, James M. Brennan Jul 1975

The Subfamily Leeuwenhoekinae In The Neotropics (Acarina: Trombiculidae), Jack T. Reed, James M. Brennan

Brigham Young University Science Bulletin, Biological Series

Neotropical representatives of the subfamily Leeuwenhoekinae are reviewed. The genus Odontacarus comprises 66 percent of the chiggers examined, and 82 percent of this genus were identified as O. tubercularis (Brennan). The following genera are redescribed: Albeckia Veracammen-Grandjean and Watkins, Leeuwenhoekia Oudemans, Odontacarus Ewing, Sasacarus Brennan and Jones, Wagenaaria Brennan, and Whartonia Ewing. New taxa are: Odontacarus comosus comosus, O. c. novemsetus, O. dienteslargus, O. pugnosus, O. schoenesetosus, O. sunnianae, O. tiptoni, O. tuberculohirsutus, O. vanderhammeni, O. vergrandi, Sasacarus furmani panamensis, and Whartonia angulascuta. Odontacarus fieldi Brennan and Jones, 1961, and O. cayolargoensis Brennan, 1959, are synonymized under O. tubercularis Brennan, …


End Matter, Vol. 20 No. 1 Jul 1975

End Matter, Vol. 20 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


A List Of Venezuela Chiggers, Particularly Of Small Mammalian Hosts (Acarina: Trombiculidae), James M. Brennan, Jack T. Reed Jul 1975

A List Of Venezuela Chiggers, Particularly Of Small Mammalian Hosts (Acarina: Trombiculidae), James M. Brennan, Jack T. Reed

Brigham Young University Science Bulletin, Biological Series

Detailed or summarized records of 136 species in 38 genera with a key to the latter are provided. Of 86 described forms, 49 are new for Venezuela; the remaining undescribed taxa are coded for purposes of this report. A classified host-parasite list is appended.


Bionomics Of Insects Associated With Corn In The Nebraska Sandhills, J. L. Wedberg, J. B. Campbell, T. J. Helms Jul 1975

Bionomics Of Insects Associated With Corn In The Nebraska Sandhills, J. L. Wedberg, J. B. Campbell, T. J. Helms

Nebraska Agricultural Experiment Station: Historical Research Bulletins

Investigations were conducted in the Nebraska Sandhills to determine the impact of transition from grassland to irrigated corn on selected insect species, to identify indigenous species that may be economically important to corn production, and to provide a point of reference for future development of pest management programs for irrigated corn.


Measurement Of Transpiration In Pinus Teada L. And Liquidambar Styraciflua L. In A Closed Environment Growth Chamber Using Tritiated Water, Jean K. Czoch Jul 1975

Measurement Of Transpiration In Pinus Teada L. And Liquidambar Styraciflua L. In A Closed Environment Growth Chamber Using Tritiated Water, Jean K. Czoch

Biological Sciences Theses & Dissertations

Transpiration rates of loblolly pine (Pinus taeda L.) and sweetgum (Liguidambar styraciflua L.) were measured at two different water vapor pressure deficits (V.P.D.) in a controlled environment growth chamber using tritiated water as a tracer. The trees were maintained in a sealed plant bed containing a hydroponic nutrient solution. Samples of leaves, chamber air, spiked nutrient and control solutions were assayed for activity using liquid scintillation techniques. The transpiration rate of sweetgum (4.95 ml/hr/gm) was found to be 5 times greater than that of loblolly pine (1.03 ml/hr/gm) at the lower V.P.D. and 8 times greater at …


Front Matter, Vol. 20 No. 1 Jul 1975

Front Matter, Vol. 20 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Leaf Freckles And Wilt Of Corn Incited By Corynebacterium Nebraskense Schuster, Hoff, Mandel, Lazar, 1972, M. L. Schuster May 1975

Leaf Freckles And Wilt Of Corn Incited By Corynebacterium Nebraskense Schuster, Hoff, Mandel, Lazar, 1972, M. L. Schuster

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The new bacterial disease Leaf Freckles and Wilt (LFW) of corn (Zea mays L.) was first observed in 1969 on two farms in southcentral Nebraska. Since then it has spread to other areas in the state. LFW is a serious disease on farms in six Nebraska counties (Clay, Custer, Dawson, Furnas, Hall and Phelps) and has been found in isolated cases in at least 28 other counties. In 1971 LFW was found in a seedcorn field in western Iowa, in 1973 in two Kansas counties, and in 1974 in South Dakota and Colorado. Because of its explosive nature, several …


Structure & Composition Of A Climax Forest System In Boone County, Kentucky, Michael Held May 1975

Structure & Composition Of A Climax Forest System In Boone County, Kentucky, Michael Held

Masters Theses & Specialist Projects

The structure and composition of a 52 hectare mature mesic hardwood forest in Boone County, Kentucky was studied during 1973-74. Acer saccharum was the dominant tree species of the entire forest, with Fraxinus americana as the subdominant. In the understory vegetation, Acer and Fraxinus were among the dominant genera, thus this forest system can be described as being at the climax stage of development. A previously cleared area in the forest was also analyzed. It was found that the dominant tree species of the canopy were also dominant in the genera of the understory in the disturbed area, indicating a …


Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson May 1975

Gas Exchange And Water Relations Of Two Alpine And Two Arctic Tundra Plant Species, Douglas Allan Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Although water stress is an important selective force in many environments, it is not commonly considered to be of particular importance in tundra areas. Even though large portions of tundra may have an abundance of water, other more exposed areas may become quite dry. This microsite variability with respect to moisture stress was reflected in soil water potential measurements obtained from an alpine tundra area on Niwot Ridge in Colorado. Even though soil water potentials were consistently above -5 bars in a relatively low lying Deschampsia meadow, soil water potentials from an exposed fellfield area were often as low as …


The Effect Of Environment And Cultural Practices On The Cold Hardiness Of Peach Wood, Larry A. Sagers May 1975

The Effect Of Environment And Cultural Practices On The Cold Hardiness Of Peach Wood, Larry A. Sagers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were conducted to better understand the effect of temperature, photoperiod, cultural practices, and growth regulators on the hardening and dehardening of peach tree wood.

Greenhouses were constructed to control temperatures to which peach trees were exposed. It was noted that hardening and dehardening usually followed the temperature fluctuation fairly closely. However, trees exposed to temperatures above 60 F (15.6 C) became hardy to 0 F (-17.8 C).

A photoperiodic response in regard to an increase or decrease in hardiness was not definitely observed in peach wood. Extended photoperiod did not produce any significant effect on hardiness. Defoliation, bloom date, …


Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz May 1975

Factors Influencing Germination And Seedling Survival Of Several Varieties Of Astragalus Lentiginosus Dougl., Paul Ziemkiewicz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Astragalus lentiginosus, which consists of 36 varieties, is one of the principal locoweeds of western North America. The objectives of this study included identification of some of the major factors affecting germination of the seed and survival of the newly established seedlings for several of these varieties.

The seeds of the varieties studied exhibited two mechanisms for dormancy. One is a seed coat that is impermeable to water, and the other is a water-leachable inhibitor. The presence or absence of low-intensity incandescent light (in 14-hour day lengths) had no effect on germination. Of three temperature regimes studied, the regime …


Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray May 1975

Nutritional Quality And Herbage Production Of Intermediate Wheatgrass (Agropyron Intermedium [Host] Beauv.) When Infested With Black Grass Bugs (Labops Hesperius Uhler), Alan M. Gray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two intermediate wheatgrass seedings with different levels of grass bug infestation were evaluated for herbage production, seedhead production, percent dry matter, crude protein, and cell contents. Study sites were located at different elevations on mountain summer ranges in northern (Site I) and central (Site II) Utah. Study plots at Site I and Site II were infested with 113 and 210 bugs per sweep, respectively. Herbage production appeared to be reduced in early spring on the site with the higher infestation; however, no effect on season-long herbage production could be detected on either site. Seedhead production on infested plots was reduced …


Plant Light Responses Under Snow, Steven G. Richardson May 1975

Plant Light Responses Under Snow, Steven G. Richardson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several montane plant species and one alpine species were observed to grow under snow, and the seeds of 19 species germinated under snow. The spectral irradiance of light penetrating up to 198 cm of snow was measured with a device employing a photomultiplier tube and a series of interference filters. In deep snow, the measured peak in transmission was near 500 nm, but in older, more shallow snow the peak was at 550 nm. On two occasions measurements were made both before and after sunrise. There was a shift in the spectra toward the longer wavelengths as the sun rose …


Folate Content Of Bacillus Subtilis, David Nelson Hintze Apr 1975

Folate Content Of Bacillus Subtilis, David Nelson Hintze

Theses and Dissertations

Bacillus subtilis can synthesize deoxythymidylate via either of two pathways. The working hypothesis is that the two reactions are very similar, differing only with respect to specificity for the type of folate required as substrate. The folates from B. subtilis were isolated and were determined by gel chromatography to be derivatives of pteroyltriglutamate and pteroyldiglutamate. Kav values for the two folate species are reported. Conjugase treatment revealed no other highly conjugated folates present. It was also observed that mutants deficient in one or the other of the two pathways grow at the same rate as wild-type cells under conditions allowing …


Diatom Phytoplankton And Periphyton Studies Of The Headwaters Of Henrys Fork Of The Snake River, Island Park, Idaho, Richard L. Clark Apr 1975

Diatom Phytoplankton And Periphyton Studies Of The Headwaters Of Henrys Fork Of The Snake River, Island Park, Idaho, Richard L. Clark

Theses and Dissertations

An ecological baseline study of the diatom flora was conducted on the headwaters of Henrys Fork of the Snake River, Idaho. The diatom flora of this spring fed drainage basin consisted of both phytoplankton and periphyton. Thirty-nine genera, two hundred forty-four species, eighty-two additional varieties, and seven additional forms were identified from these waters. Species of Melosira, Stephanodiscus, Fragilaria, Synedra, and Asterionella were found in the plankton of Henrys Lake and Island Park Reservoir. Diatoma, Fragilaria, Synedra, Eunotia, Achnanthes, Navicula, Pinnularia, Gomphonema, Cymbella, Nitzschia, and Surirella were the important genera present in the periphyton.


An Assay Chamber For Quantitative Analysis Of Nitrogen Fixation Using Intact Plants, Thomas Adrie Leslie Apr 1975

An Assay Chamber For Quantitative Analysis Of Nitrogen Fixation Using Intact Plants, Thomas Adrie Leslie

Theses and Dissertations

A unique assay system for quantitative analysis of biological nitrogen fixation by intact plants has been constructed and successfully tested. With the system, it has been possible to detect acetylene reduction by intact legumes in situ under laboratory conditions. This assay method is designed to approximate field conditions and in spite of possible procedural errors in sampling, background noise of the gas chromatograph and ethylene contamination of the acetylene gas used in the assay, this method is sensitive ·enough to detect as little as 1 ppm enrichment of ethylene gas as a result of acetylene reduction by intact soybean plants. …


An Investigation Of The Ecology Of Subalpine Fir On The Markagunt Plateau In Southern Utah, Ronald Beatty Bolander Apr 1975

An Investigation Of The Ecology Of Subalpine Fir On The Markagunt Plateau In Southern Utah, Ronald Beatty Bolander

Theses and Dissertations

The ecology of subalpine fir relative to broom rust was investigated. Broom rust infections were most common in trees growing on limestone soils, and seldom occurred on trees growing on basalt soils. Even though plant moisture stress was consistently higher in the plants from limestone soils, the studies indicated that moisture stress is not the major factor causing infection. The amounts of available magnesium and phosphorus were much lower in the limestone soil. It is postulated that the higher plant moisture stress of subalpine fir growing on limestone soils may aggrevate the lack of nutrients and be a contributing factor …


James Valley Agricultural Research And Extension Center Annual Progress Report, 1975, Agricultural Experiment Station, Plant Science Department Mar 1975

James Valley Agricultural Research And Extension Center Annual Progress Report, 1975, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1975 progress report for the James Valley Agricultural Research and Extension Center. The reports in this document represent the research conducted at the Center during 1974. The report includes weather data, information on crop production, irrigation, performance and variety test, and fertilizer usage.


Jasminum Primulinum Hemsl. Ex Baker, Linda Rhea Mar 1975

Jasminum Primulinum Hemsl. Ex Baker, Linda Rhea

Specimens by Name

No abstract provided.


The Prairie Naturalist Volume 7, No.1. March 1975 Mar 1975

The Prairie Naturalist Volume 7, No.1. March 1975

The Prairie Naturalist

MIGRATION OF BIRDS IN NORTH DAKOTA DURING FAll 1974 ▪ J. T. Lokemoen & D. H. Johnson.

REPRODUCTION AND DEVELOPMENT OF FOUR MALLARD LINES ▪ R. J. Greenwood


Survival Factors Of Plant Pathogenic Bacteria, M. L. Schuster, D. P. Coyne Feb 1975

Survival Factors Of Plant Pathogenic Bacteria, M. L. Schuster, D. P. Coyne

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The research works discussed in this review were selected to provide a cross section of the phenomenon of survival of plant pathogenic bacteria.


An Iteration Formula For Finding Roots Of Equations, R. W. P. Masenge Jan 1975

An Iteration Formula For Finding Roots Of Equations, R. W. P. Masenge

Tanzania Journal of Science

We seek the roots of the equation f(x) = 0.


Phomopsis : The Causal Fungus Of Lupinosis, P Mcr Wood, A. G. P. Brown Jan 1975

Phomopsis : The Causal Fungus Of Lupinosis, P Mcr Wood, A. G. P. Brown

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

It is now well known that lupinosis of sheep and cattle follows ingestion of lupin stubble colonised by the fungus Phomopsis rossiana. The fungus infects green lupins but persists on the stubble and under certain conditions apparently produces a toxin which causes the disease.

As Phomopsis is now widespread on lupins in Western Australia its ecology has been studied in detail as a basis for possible control measures.

This article outlines what is known so far of the disease and its control.


Isoenzymes Of Datura Meteloides (Solanaceae). Developmental Patterns And Tissue Specificities, Ron L. Scogin Jan 1975

Isoenzymes Of Datura Meteloides (Solanaceae). Developmental Patterns And Tissue Specificities, Ron L. Scogin

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Abronia: Iii. Pericarp And Seed Coat Anatomy And Its Ecological Implications For Nine Species Of Abronia, Ruth C. Wilson Jan 1975

Abronia: Iii. Pericarp And Seed Coat Anatomy And Its Ecological Implications For Nine Species Of Abronia, Ruth C. Wilson

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.