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Internal Water Potential Of An Engelmann Spruce Stand In Relation To Soil And Atmospheric Factors, Richard L. Meyn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary objective of this study was to determine the degree of correlation between internal water potential of Engelmann spruce trees and selected environmental factors. The secondary objective of the study was to determine the effect of summer precipitation, both in meadow and forested sites, on the soil drying cycle.

Four study plots (each roughly 154 square meters) under spruce cover and two study plots (100 square meters) in a small meadow were established. At each spruce plot, a thermocouple psychrometer was installed at one meter above the ground on the north side of three selected, mature Engelmann spruce trees. …

Autecological Life History Studies Of Two Geraniums, Geranium Richardsonii And Geranium Nervosum, Becky Lee Green

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two perennial species of wild geranium (Geranium nervosum Rydb. and G. richardsonii Fisch, and Trautv, [Geraniaceae]) which grow throughout the mountainous regions of western North America were studied to determine the factors influencing the life stage development and distribution of these plants. Attempts were also made to provide some information to assist in the taxonomy of this genus.

Geranium richardsonii is found in wet meadows and along streambanks throughout its distribution. Geranium nervosum frequents rocky hillsides and drier meadows throughout its range.

Seeds of G. nervosum had 65%, germination in the stratification pretreatment. Geranium richardsonii seeds required scarification to …

Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In seasons of above normal precipitation, populations of annual weedy species increase in great abundance in semi-arid desert plant communities. These increases in biomass tie up a considerable portion of the available nitrogen of such ecosystems and may depress subsequent annual grass germination.

A big sagebrush-annual bromegrass plant community was irrigated to simulate a spring growth period of abundant precipitation amenable to annual bromegras s productivity. Productivity and nitrogen content parameters were monitored throughout the spring and summer to evaluate the short and potential long term effects of this seasonal increase in "precipitation".

Irrigation increased annual bromegrass productivity almost 50 …

Field Measurements Of Photosynthesis And Leaf Growth Rates Of Three Alpine Plant Species, Douglas A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaf photosynthetic measurements using a portable ¹⁴Co₂ field system were carried out and correlative leaf relative growth rates, RGR, were determined at different leaf positions of three alpine plant species throughout the growing season. Initially there was a period of high leaf RGR associated with a period of increasing photosynthetic activity. Following this stage was a long period of no net change in length of the living leaf. During this period, photosynthetic activity generally increased to a maximum level and then decreased steadily. The final ontogenetic stage was a period of negative leaf RGR denoting leaf senescence which …

Formation And Control Of Chlorophyll, Solanine Alkaloids, And Sprouts Of Potato (Solanum Tuberosum L.) Tubers And Carbonyl Compound Of Tomato (Lycopersicon Esculentum Mill.) Fruits, S. J. Jadhav

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Part I. Formation and control of chlorophyll, solanine alkaloids, and sprouts of potato (Solanum tuberosum L.) tubers

Incorporation of radioactive carbon from acetic acid-2-¹⁴C (sodium salt), β-hydroxy-β-methylglutaric acid (HMG)-3-¹⁴C, L-leucine-U-¹⁴C, L-alanine-U-¹⁴C, and D-glucose-U-¹⁴C into the predominant glycosidic steroidal alkaloids, ⍺-solanine and ⍺-chaconine of potato sprouts was 4.88, 9.0, 15, 24, and 20 times less than that of mevalonic acid (MVA)=2-¹⁴C (DBED salt), respectively. The efficiency ratio revealed that β-hydroxy-β-methylglutaric acid (HMG)-3-¹⁴C was incorporated via acetate or acetoacetate. The distribution of radioactivity originated from D-glucose-U-^{14 …}

Cytogenetic Effects Of Vitavax Fungicide On Secale Cereale On Allium Cepa, Jack Ernest Staub

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of Vitavax fungicide (2,3-dihydro-5-carboxanilido-6-methyl-1,4-oxathiin) on meiotic chromosomes of rye (Secale cereale) and mitotic chromosomes of onion (Allium cepa) and rye were observed.

The principal aberrations recorded in pollen mother cells of rye were: 1-4 univalents at metaphase I; sticky bridges at telophase I; and micronuclei and misshapen nuclei at the quartet stage.

The principal aberrations recorded in root tip mitoses in onion and rye were: chromosome fragmentation, disintegration, clumping, aggregation and inhibition of mitosis.

All meiotic phases were significantly affected by 1,000, 5,000,10,000, 33,300, 66,600 ppm Vitavax at the 48, 72, and 96 hour …

Temperature Effect On Leaf Water Potential Measurements, Rex J. Prosser

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Silver foil psychrometers were used to monitor water potential in different portions of maize leaves which were subjected to temperature gradients. The psychrometers were preliminarily calibrated over standard NaCI solutions at temperatures ranging from 5°C to 45°C in an aluminum plate apparatus designed to provide uniform temperatures within each psychrometer even while overall temperature was changing. Based on the calibrations, empirical temperature correction equations were derived and used to correct psychrometer readings at different temperatures to equivalent values at 25°C. Temperatures on a single maize leaf were varied by placing the long leaf through an insulated box with several compartments …

The Effect Of The Herbicide Glyphosate On The Growth Of Selenastrum Capricornutum, Judith Susan Eisen

Undergraduate Honors Capstone Projects

The herbicide glyphosate (MON-0139), an isopropylamine salt of N- (phosphonemethyl)glycine, was tested to determine its effects on the growth of the fresh water green alga Selenastrum capricornutum. Experiments were carried out to determine algicidal, algistatic, and inhibitory concentrations of the compound.

Concentrations from 5 ppm to 1000 ppm were inhibitory to the growth of the alga, but the effects were algistatic, rather than algicidal. At concentrations from 0.1 ppm to 1.0 ppm the growth of the alga was stimulated by the presence of the herbicide, while at concentrations from 0.001 ppm to 0.05 ppm the effects of the herbicide were …