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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

An economic evaluation of the effectiveness of the Texas Pecan Checkoff Program

Moore, Eli Del 15 May 2009 (has links)
The Texas Pecan Board was established in 1998 to administer the Texas Pecan Checkoff Program and is financed through a one-half cent per pound assessment on grower pecan sales. The Board spends the assessment collections on a variety of advertising campaigns in an attempt to expand demand for Texas pecans, both improved and native varieties, and increase the welfare of Texas pecan growers. This study presents an evaluation of the economic effectiveness of the Texas Pecan Checkoff Program in expanding sales of Texas pecans. First, the effects of Texas Pecan Board promotion on sales of all Texas pecans are determined using the ordinary least squares estimator (OLS) followed by a test for differential effects of Texas Pecan Board promotion on sales of improved and native Texas pecan varieties using the seemingly unrelated regression. The analysis indicates that the Texas Pecan Checkoff Program has effectively increased sales of improved varieties of Texas pecans, but has had no impact on sales of native varieties of Texas pecans. A benefit-cost analysis determines that the additional sales revenues generated is relatively large compared to the dollar value spent on promotion indicating that the Texas pecan promotion program has been financially successful.
22

The quantification of blackmargined aphid (Monellia caryella (Fitch)) honeydew production in pecan (Carya illinoinensis (Koch)) in Texas

Honaker, Jessica Marie 15 May 2009 (has links)
Field studies of the blackmargined aphid, Monellia caryella (Fitch), were conducted on three cultivars, ‘Cheyenne’, ‘Kiowa’, and ‘Pawnee’, of pecan, Carya illinoinensis (Koch). Aphid density and natural enemy (lacewings, ladybird beetles, and spiders) densities were determined biweekly by direct inspection of 160 leaves per variety during the 2005 and 2006 growing seasons. Honeydew deposition was measured biweekly using water sensitive cards. Aphid phenologies were similar among cultivars; however, ‘Cheyenne’ supported higher densities of aphids than either ‘Kiowa’ or ‘Pawnee’. Honeydew production correlated positively with aphid density. Honeydew produced per aphid differed only between ‘Cheyenne’ and ‘Pawnee’ in 2006; natural enemies per aphid varied in significance during both seasons. Natural enemy densities increased during initial stages of outbreak on all cultivars in 2006. The asymptote reached on ‘Cheyenne’ had a lower natural enemy to aphid ratio than that on the other cultivars, indicating that the functional response of natural enemies to increased aphid densities was exhausted sooner on ‘Cheyenne than on other cultivars’. Honeydew appears to be an attractant for natural enemies and cost-benefit calculations were made to quantify the loss of photosynthates to aphids for each cultivar versus the gain in natural enemies that occurred. ‘Cheyenne’ was the least efficient of the three cultivars in the utilization of this defense mechanism. The energy drain per hectare attributable by adult aphid feeding was, 761,197 – 900,312kcal, 266,397 – 237,709kcal, and 138,790 – 134,223kcal for ‘Cheyenne’, ‘Kiowa’, and ‘Pawnee’, respectively. Calculated nut-loss equivalents were 14 – 16kg for ‘Cheyenne’, 4 – 5kg for ‘Kiowa’, and 2kg for ‘Pawnee’.
23

An economic evaluation of the effectiveness of the Texas Pecan Checkoff Program

Moore, Eli Del 15 May 2009 (has links)
The Texas Pecan Board was established in 1998 to administer the Texas Pecan Checkoff Program and is financed through a one-half cent per pound assessment on grower pecan sales. The Board spends the assessment collections on a variety of advertising campaigns in an attempt to expand demand for Texas pecans, both improved and native varieties, and increase the welfare of Texas pecan growers. This study presents an evaluation of the economic effectiveness of the Texas Pecan Checkoff Program in expanding sales of Texas pecans. First, the effects of Texas Pecan Board promotion on sales of all Texas pecans are determined using the ordinary least squares estimator (OLS) followed by a test for differential effects of Texas Pecan Board promotion on sales of improved and native Texas pecan varieties using the seemingly unrelated regression. The analysis indicates that the Texas Pecan Checkoff Program has effectively increased sales of improved varieties of Texas pecans, but has had no impact on sales of native varieties of Texas pecans. A benefit-cost analysis determines that the additional sales revenues generated is relatively large compared to the dollar value spent on promotion indicating that the Texas pecan promotion program has been financially successful.
24

The quantification of blackmargined aphid (Monellia caryella (Fitch)) honeydew production in pecan (Carya illinoinensis (Koch)) in Texas

Honaker, Jessica Marie 10 October 2008 (has links)
Field studies of the blackmargined aphid, Monellia caryella (Fitch), were conducted on three cultivars, 'Cheyenne', 'Kiowa', and 'Pawnee', of pecan, Carya illinoinensis (Koch). Aphid density and natural enemy (lacewings, ladybird beetles, and spiders) densities were determined biweekly by direct inspection of 160 leaves per variety during the 2005 and 2006 growing seasons. Honeydew deposition was measured biweekly using water sensitive cards. Aphid phenologies were similar among cultivars; however, 'Cheyenne' supported higher densities of aphids than either 'Kiowa' or 'Pawnee'. Honeydew production correlated positively with aphid density. Honeydew produced per aphid differed only between 'Cheyenne' and 'Pawnee' in 2006; natural enemies per aphid varied in significance during both seasons. Natural enemy densities increased during initial stages of outbreak on all cultivars in 2006. The asymptote reached on 'Cheyenne' had a lower natural enemy to aphid ratio than that on the other cultivars, indicating that the functional response of natural enemies to increased aphid densities was exhausted sooner on 'Cheyenne than on other cultivars'. Honeydew appears to be an attractant for natural enemies and cost-benefit calculations were made to quantify the loss of photosynthates to aphids for each cultivar versus the gain in natural enemies that occurred. 'Cheyenne' was the least efficient of the three cultivars in the utilization of this defense mechanism. The energy drain per hectare attributable by adult aphid feeding was, 761,197 - 900,312kcal, 266,397 - 237,709kcal, and 138,790 - 134,223kcal for 'Cheyenne' , 'Kiowa', and 'Pawnee', respectively. Calculated nut-loss equivalents were 14 - 16kg for 'Cheyenne', 4 - 5kg for 'Kiowa', and 2kg for 'Pawnee'.
25

Chemical composition of select pecan [Carya illinoinensis (Wangenh.) K. Koch] varieties and antigenic stability of pecan proteins

Venkatachalam, Mahesh. Sathe, Shridhar K. January 2004 (has links)
Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Dr. Shridhar K. Sathe, Florida State University, College of Human Sciences, Dept. of Nutrition, Food and Exercise Sciences. Title and description from dissertation home page (viewed Sept. 23, 2004). Includes bibliographical references.
26

A Quantitative and Qualitative Bacterial Analysis of Pecan Creek

Cook, Vernice 08 1900 (has links)
Since Pecan Creek receives sewage wastes from an obviously inadequate disposal system, it seemed possible that it could receive pathogenic bacteria. The fact that these might be present in numbers sufficient to cause epidemics, provided the proper natural vectors were present, stimulated an interest in and the pursuance of this study.
27

Use of Automated Sampler to Characterize Urban Stormwater Runoff in Pecan Creek

Appel, Patrick L. 12 1900 (has links)
The purpose of this study was to use the Global Water Stormwater Sampler SS201 to characterize the urban runoff in Pecan Creek. Location of the samplers was influenced by land use and ease of installation. Determination of the constituents for analysis was modeled after those used in the NPDES permit for seven cities within the Dallas/Ft.Worth metroplex. Some metals, notably cadmium and arsenic, exceeded the U.S. EPA's MCL's. Statistical analysis revealed first flush samples to be significantly more concentrated than composite samples. Minimum discharge loadings were found to be significantly lower than maximum discharge loadings. Additionally there were significant differences of specific constituents between station locations and storm events.
28

Foliar Applications of Boron to Pecan Trees Does Not Affect Fruit Set

Kilby, Michael W., Call, Robert 09 1900 (has links)
Boron was applied as a foliar spray to pecan trees in a pecan orchard located in Cochise County. Single or repeated application prior to pollination did not affect nutlet set. Leaf analysis indicated that the boron levels in all trees were in the sufficient range for optimum growth and production.
29

Influence of Nut Cluster Position on the Incidence of Viviparity for the Pecan Cultivars "Western Schley" and "Wichita"

Gibson, Richard, Kilby, Michael 09 1900 (has links)
Vivaparity, a significant quality- reducing condition found in pecans grown in warm, temperate climates, was evaluated by location of the pecan nut within the cluster in two varieties, "Wichita " and "Western Schley". Percentage vivaparity was not affected by position.
30

Revitalizing "Wichita" Pecan Productivity Through Corrective Pruning - First Year Results

Gibson, Richard, Kilby, Michael 09 1900 (has links)
A pruning study was established in stressed pecan trees to identify effective means of returning unproductive trees to full productivity. The study was comprised of two pruning systems and one untreated check. The number of nuts harvested from pruned trees was lower than that harvested from the unpruned trees, but the quality of the nuts from the pruned trees was improved when compared with the unpruned trees.

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