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SC-0051 and SC-0774 are two experimental herbicides of undisclosed chemistry. A three year field study was conducted to evaluate SC-0051 and SC-0774 for weed control in conventional and no-till corn in Virginia. SC-0051 applied preemergence or postemergence, controlled common lambs-quarters (Chenopodium album L.), common ragweed (Ambrosia artemisiifolia L.) horseweed (Conyza canadensis (L.) Cronq.), common chickweed (Stellaria media (L.) Vill. and was safe to corn. SC-0051 did not control smooth pigweed (Amaranthus hybridus L.) or giant foxtail (Setaria faberi Herrm.). SC-0774 effectively controlled the rye (Secale cereale) cover crop and large crabgrass (Digitaria sanguinalis (L. Scop.) but did not control broadleaf weeds or giant foxtail. SC-0774 also caused considerable but temporary corn injury when applied at rates above 1.1 kg/ha. Combinations of SC-0051 and atrazine provided broad spectrum weed control and yields comparable to atrazine plus metolachlor. Field and laboratory studies were conducted to evaluate the effect of soil pH on the soil mobility of SC-0051 and SC-0774 in sandy loam soils. SC-0774 was applied to soils amended to high and low pH and samples were collected by depth throughout the growing season. A method was developed for extracting and quantifying SC-0774 from collected soil samples. Large crabgrass was also used as a bioindicator species for qualitative detection of SC-0774 residues. These studies showed that SC-0774 was significantly more mobile in high pH soil than in low pH soil. Also, the decreased mobility of SC-0774 at low soil pH lead to decreased corn injury but it increased the soil residual activity of this herbicide. Soil column studies with SC-0774 and SC-0051 showed that the soil mobility of both herbicides increased with increasing soil pH. These herbicides cause reductions in chlorophyll and carotenoid levels in susceptible species resulting in a bleached appearance. The mechanism of this bleaching action is not known. Studies were conducted which examined the effect of SC-0051 on the pigment content and quantity in the susceptible species soybean. High performance liquid chromatography was used to separate, quantify, and identify pigments present in extracts of bleached tissues. The bleaching herbicide norflurazon was also examined for comparison purposes. SC-0051 and norflurazon inhibited the biosynthesis of carotenoids while causing an accumulation of the carotene precursor phytoene and an additional, unidentified pigment that appears to be structurally related to phytoene. This indicates that SC-0051, like norflurazon, inhibits carotenoid formation by blocking the desaturation of phytoene to phytofluene. The uptake and translocation of ¹⁴C-SC-0051 into tolerant corn and susceptible soybean seedlings was examined under growth chamber conditions to investigate the basis for the selectivity of this herbicide. Herbicide uptake was similar in both species but the susceptible soybean translocated a higher percentage of the ¹⁴C-SC-0051 to the growing point of new tissues than did the tolerant corn. It is proposed that differential translocation plays a role in the crop selectivity of the herbicide SC-0051. / Ph. D.

Cotton (Gossypium hirsutum L.), is cultivated in the United States, primarily in regions characterized by long, hot summers to optimize plant growth. Virginia is the northernmost state where cotton is grown, with approximately 84,000 acres annually. The unique challenges of cultivating cotton in Virginia stems from its relatively short season due to its geographical location, lack of large contiguous acreage, and distinctive issues with pests. A significant pest of this region is the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), which emerged as a major threat to mid-Atlantic cotton during the late 2010s. L. lineolaris utilize a variety of wild and cultivated hosts to survive the winter months. The overwintering success and distribution of diapause survival L. lineolaris was measured on cover crops and weeds common in the Mid-Atlantic. Densities varied between weed and cultivated hosts, with L. lineolaris exhibiting increased survival in legumes compared to grains. Carbohydrate, lipid and protein levels were measured within diapausing and non-diapausing L. lineolaris specimens. Overwintering specimens usually had elevated level of carbohydrates and lipids, while containing decreased concentrations of protein. Nutrient quantification provided an effective tool in selecting for diapause status in L. lineolaris. Through the results from this study, an alternative method to dissection for determining diapause status in L. lineolaris has been identified. In the spring, movement of L. lineolaris throughout the landscape is highly dependent on host senesce. Flight analysis, behavioral assays and nutritional quantification assays on L. lineolaris populations from different weed hosts were performed to assess the flight capacity of specimens fed from different hosts. While weed hosts type provided populations with differing internal nutrient levels, sustained flight was not different between populations. When dispersal of L. lineolaris into cotton occurs, insecticide treatments following scouting are often necessary to prevent economic damage to the plant. Insecticide experiments were conducted aiming to assess the impact of different active ingredients on L. lineolaris, secondary pests, and natural enemy populations. Findings indicated that insecticides used to control L. lineolaris were successful at lowering pest populations and acephate was found to impact natural enemy populations. Plots applied with acephate experienced secondary pest outbreaks, highlighting the crucial role of natural enemies. / Doctor of Philosophy / Cotton is cultivated throughout the southern United States, extending up the east coast and into North Carolina and Virginia. Virginia poses unique challenges for cotton growers due to specific pest issues and need for region-specific research. The tarnished plant bug is a key pest of mid-summer cotton across this region. Overwintering studies were conducted to investigate host preferences on cover crop and weed hosts, as well as diapause survival and termination timing on cover crops. These studies revealed that hairy vetch and deadnettle species may harbor larger populations compared to other weed hosts, and that cover crops such as hairy vetch and crimson clove led to greater overwintering survival compared to grains. During diapause, metabolic changes occur that can lead to increased fat body to aid in overwintering survival. Diapausing and non-diapausing tarnished plant bugs were used in assays to quantify differences in the nutrients commonly found in this fat body. This study successfully found differences in carbohydrates, lipids and proteins levels between the diapausing and non-diapausing populations. This may allow for the identification of reproductive status of tarnished plant bugs based on nutrient levels. Flight capacity, activity levels and nutrient levels in tarnished plant bug populations taken from spring and summer weed hosts were investigated, with the objective to understand the ability of these populations to transition to cotton in the mid-summer. There were some indicators that flight initiation may be influenced by weed host, while all populations had similar flight potentials. Once in cotton, tarnished plant bugs are primarily treated with chemical insecticides which may produce unknown consequences to the system as a whole. Experiments were conducted to assess the impact of insecticides on non-target species within cotton were conducted in the field. Certain insecticides were identified to be harmful to non-target and potentially beneficial insect species, which contributed to outbreaks of other secondary pest species.

A computer simulation model written in PL/I of the flowering phenology of C. thoermeri and the seasonal population dynamics of R. conicus was constructed based on a synthesis of the literature, and on laboratory experiments which determined developmental periods, mortality for immature stages and the ovipositional pattern of R. conicus. The model successfully simulated the ovipositional pattern of R. conicus and the flowering phenology of C. thoermeri. Larval population dynamics of R. conicus, in the model however, did not fit the validation data. Though the model was temporally synchronized with the field data, the model results were one degree of magnitude less. The poor fit was attributed to sampling errors in the validation data. Studies of the overwintering mortalities of both organisms were performed. R. conicus was found to overwinter with lowest mortality on musk thistle rosettes; mortality was 73.6% in 1981, higher than previously reported but possibly more representative of field conditions. No overwintering mortality was observed for established rosettes of C. thoermeri. Studies of seed dispersal of C. thoermeri were performed to determine the percentage of seeds removed from the vicinity of the plant where they originated. Seed dispersal observed for different wind velocities demonstrated that less than 1% of seeds are blown further than 100m and most seeds are deposited within 50m of the release site. A Gaussian model of seed dispersal based on experimentally determined parameters and literature values corroborated these results. / Master of Science

Studies were conducted to determine the distribution of s-triazine resistant biotypes of common lambsquarters (Chenopodium album L.) and smooth pigweed (Amaranthus hybridus L.) in Virginia. Collections of seed were made from suspected triazine-resistant biotypes of common lambsquarters and smooth pigweed from counties in Virginia which had reported having triazine resistance problems. Triazine resistance was confirmed by measuring chlorophyll fluorescence in the presence of atrazine. For further confirmation of triazine resistance in collected common lambsquarters and smooth pigweed biotypes, greenhouse testing of whole plants and a sinking leaf disc assay were performed. Cross-resistance to another s-triazine, as-triazine, and substituted urea herbicide was also determined for s-triazine-resistant biotypes. These studies have shown triazine- resistant smooth pigweed to be present in 19 counties and common lambsquarters to be present in 8 counties in Virginia. s-Triazine resistant biotypes were found to be resistant to another s-triazine and as-triazine herbicide, but were susceptible to the substituted urea herbicide. Additional studies were initiated to determine the effects of different temperature regimes on triazine-resistant and -susceptible biotypes of common lambsquarters and smooth pigweed from different geographical locations. These studies were conducted at the North Carolina State University Phytotron facility in controlled environment growth chambers. Triazine-resistant common lambsquarters biotypes from Virginia, Maryland, and Switzerland as well as a smooth pigweed biotype from Virginia were examined. Triazine-susceptible biotypes of common lambsquarters and smooth pigweed were included as controls. Shoot height, weight, chlorophyll a and b content, and whole leaf fatty acid content of common lambsquarters and smooth pigweed were determined at 18°/14° C, 26°/22° C, and 36°/26° C. Measurements of shoot height were made at 30 and 63 days after planting. The shoot weight, chlorophyll a and b content, and fatty acid content was determined from plants harvested at 63 days after planting. These data indicate common lambsquarters biotypes from different geographical regions exhibited a differential response to temperature. There was no difference between triazine-resistant and -susceptible biotypes in response to temperature. Differences were detected between triazine-resistant smooth pigweed biotypes which indicated that the susceptible biotypes were more vigorous as indicated by shoot height and weight at lower temperatures than triazine-resistant biotypes of smooth pigweed. / M.S.

The purpose of this investigation was to study the behavior during electrolysis of the waste from the ammonia recovery still of the Solvay Process. Data was obtained to show the effect on chlorate formation of the variables; temperature, concentration of electrolyte, and current concentration. In all the experimental runs, observations were made of the weight of calcium scale formed on the cathode surface end of the anode consumption. The temperature studies were made at 25°C, 45°C., and 60°C. The concentration studies were made with waste varying in composition from the concentration given by T.P. Hou ⁽¹²⁾ for the product of the ammonia recovery still to a concentration three times as great. The current concentration studies were made at current concentrations of 2, 4, and 6 amperes per liter. Three runs were made at 8 amperes per liter. / Master of Science

No / An ethnobiological field study on food plants and medicinal foods traditionally consumed in three Arbëresh (ethnic Albanian) communities in northern Lucania (southern Italy) document approximately 120 botanical taxa used for these purposes. Non-domesticated food vegetables (liakra), mostly gathered during the spring season, play a central role as traditional functional food. Quantitative ethnobotanical, ethnotaxonomical, ethnoecological, ethnogastronomical, and ethnopharmacological aspects related to gathering, processing, cooking and consumption of liakra are discussed. Unusual food species, such as Lycium europeaum, Centaurea calcitrapa, and a few spontaneous weedy Asteraceae and Brassicaceae species are locally used in the kitchen. Most of these are very poorly known phytochemically and phytopharmacologically. Moreover, an analysis of taste perception of the most commonly used botanical foods was conducted in the village of Ginestra. Arbëresh taste classification and indigenous criteria related to the perception of bitter taste in considering non-cultivated plants as food or medicine are discussed as well.

<p>Syftet med denna uppsats är att jämföra ett av Ozus tidigare verk stumfilmen A STORY OF FLOATING WEEDS (1934) med ett senare, färg- och ljudfilmen FLOATING WEEDS (1959). Hur skiljer sig dessa åt stilistiskt, vad förenar dem, vad följer t ex av närvaron av färg och ljud i den senare och avsaknaden av desamma i den tidigare filmen.</p><p>Analysen utgår från ett neoformalistiskt perspektiv och i en teoretisk genomgång redogörs för denna inriktnings begreppsapparat. Centrala begrepp häri är t ex främmandegörning, d v s av-naturaliseringen av den vardagliga perceptionen, stil, definierat som innefattande allt i verket, stilgrepp – det enskilda uttrycket isolerat, fabel, sujett, greppets funktion och bakomliggande motiv samt idén om den parametriska formen – verket som strukturerat efter en stilmässig dominant överordnad berättelsen.</p><p>Uppsatsen inkluderar även ett inledande kapitel vari tidigare forskning kring regissören redogörs för. Donald Richie är här en centralgestalt och uppsatsen pekar på den konflikt som kan skönjas mellan Richies traditionella budskapsorienterade perspektiv och neoformalismen.</p><p>Vidare diskuteras regissörens egensinniga stil och uppmärksamhet ägnas aspekter som t ex den lågt placerade kameran, rummet som ordnat kring 360 grader, det estetiskt motiverade rummet, mellan-liggande rum, hypermarkerade objekt, sujikai, rumsliga ankare, grafisk gestaltning och pillow-shots. Även budskapsorienterade tolkningar som återkommer i diskursen kring regissören ges utrymme, som idén om Mono no Aware, förnimmelsen om alltings förgänglighet och Mu, tomhet som närvaro.</p><p>I analysdelen studeras sedan olika sekvenser i båda verken utifrån dessa stilistiska aspekter. Slutsatsen blir att även om nya teknologier såsom färg och ljud ger upphov till nya grepp så ordnas dessa nya grepp i någon mån in i den befintliga logiken – in i dominanten. Den tydligaste skillnaden mellan verken utöver dessa tillkomna stilistiska aspekter finns i sujetten som antar en än mer episodisk struktur i den senare filmen.</p>

Syftet med denna uppsats är att jämföra ett av Ozus tidigare verk stumfilmen A STORY OF FLOATING WEEDS (1934) med ett senare, färg- och ljudfilmen FLOATING WEEDS (1959). Hur skiljer sig dessa åt stilistiskt, vad förenar dem, vad följer t ex av närvaron av färg och ljud i den senare och avsaknaden av desamma i den tidigare filmen. Analysen utgår från ett neoformalistiskt perspektiv och i en teoretisk genomgång redogörs för denna inriktnings begreppsapparat. Centrala begrepp häri är t ex främmandegörning, d v s av-naturaliseringen av den vardagliga perceptionen, stil, definierat som innefattande allt i verket, stilgrepp – det enskilda uttrycket isolerat, fabel, sujett, greppets funktion och bakomliggande motiv samt idén om den parametriska formen – verket som strukturerat efter en stilmässig dominant överordnad berättelsen. Uppsatsen inkluderar även ett inledande kapitel vari tidigare forskning kring regissören redogörs för. Donald Richie är här en centralgestalt och uppsatsen pekar på den konflikt som kan skönjas mellan Richies traditionella budskapsorienterade perspektiv och neoformalismen. Vidare diskuteras regissörens egensinniga stil och uppmärksamhet ägnas aspekter som t ex den lågt placerade kameran, rummet som ordnat kring 360 grader, det estetiskt motiverade rummet, mellan-liggande rum, hypermarkerade objekt, sujikai, rumsliga ankare, grafisk gestaltning och pillow-shots. Även budskapsorienterade tolkningar som återkommer i diskursen kring regissören ges utrymme, som idén om Mono no Aware, förnimmelsen om alltings förgänglighet och Mu, tomhet som närvaro. I analysdelen studeras sedan olika sekvenser i båda verken utifrån dessa stilistiska aspekter. Slutsatsen blir att även om nya teknologier såsom färg och ljud ger upphov till nya grepp så ordnas dessa nya grepp i någon mån in i den befintliga logiken – in i dominanten. Den tydligaste skillnaden mellan verken utöver dessa tillkomna stilistiska aspekter finns i sujetten som antar en än mer episodisk struktur i den senare filmen.

Thesis (Ph.D.)--Mississippi State University. Department of Biological Sciences. / Title from title screen. Includes bibliographical references.