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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.
71

The Golf Industry in Arizona: An Economic Summary

Wade, James C., Barkley, David January 1989 (has links)
In 1987, 191 golf facilities in Arizona were surveyed to determine the employment, income, revenues, and expenditures generated by the state's golf course industry. The direct plus indirect employment and income benefits are estimated to be 12,400 jobs and $155 million in wages, respectively.
72

Winter Turf Performance Trials

Kopec, David M., Mancino, Charles F., Ralowicz, Andrew E., Petty, Michael J., Olson, Mark, Moharram, Hisham N. January 1989 (has links)
Overseeding trials were conducted to evaluate the turf-type fitness of cool season grasses for use in the desert when bermudagrass is dormant. Perennial ryegrass, fine fescues, rough stalk bluegrasses and creeping bentgrasses were tested for turfgrass quality, color, percent ground cover and uniformity under a close mowing (3/8 inch) regime. Entries varied significantly from each other once seasonal hard frosts did not recur after January. Certain entries had better turf performance under hot (late spring) conditions. Both commercially available and experimental germplasm were evaluated.
73

Turfgrass Evaluations of Curly Mequitegrass, Hilaria belangeri (Steud.) Nash.

Ralowicz, A. E., Mancino, C. F., Maricic, A., Nelson, D., Kopec, D. M. January 1989 (has links)
Curly mesquitegrass, Hilaria belangeri, is being evaluated for utilization as a desert turf. Experiments were conducted on plant material collected throughout Arizona to: (a) quantify the natural variation in turfgrass qualities in this species; (b) evaluate the field performance of selected plant material to fertilizing and mowing practices; and (c) assess the effects of planting date and seeding rate on seedling establishment. Thirty-four percent of the rated plant material displayed low growing height while 26.9 % of the plant material had short leaf length. Thirty-five and 23.5 % of the rated plant material had acceptable or better than acceptable color ratings and fine leaf width, respectively. In another experiment, nitrogen had no significant effect on plant color, however, increasing nitrogen increased percent ground cover. Percent ground cover also increased as the height of cut increased. Substantial variation was observed in the number of stolons per plant, and high stolon numbers were not associated with high nitrogen levels. Planting time had a significant influence on seedling establishment. Seeding rates also differed significantly in the number of seedlings established per m².
74

Germination of Lehman Lovegrass and Black Grama Under Controlled Environment Conditions

Kopec, D. M., Scott, R., Munda, B. D., Pater, M. J., Mancino, C. F., Ralowicz, A. E. January 1989 (has links)
Mechanical scarification greatly improved the germination of Lehmann Lovegrass seed. Depending on the type and duration of scarification, seed gemzination can be improved from 10 %-12% germination (untreated seed) to over 90% (60-second scarification in a commercial seed scarifier). Black grama is sensitive to both dehulling and dehulling followed by scarification. Unhulled black grama seed should be used for field plantings.
75

Characterization of Amino Acids and Carbohydrates Found in Whitefly Honeydew As the First Step Toward Bioloical Control

Byrne, D. N., Miller, W. B., Stanghellini, M. E. January 1989 (has links)
A Florida strain of sweet potato whitefly, Bemisia tabaci (Gennadius), was found to have an expanded range which includes several new food crops. To determine why, we examined how it processes plant nutrients. The amino acid and carbohydrate content of phloem sap of poinsettia and pumpkin and of honeydew produced by the Florida strain and a strain from Arizona feeding on both plants were analyzed. Poinsettia phloem sap contained 15 amino acids; 14 of these were in pumpkin phloem sap. Almost all the same amino acids were in the honeydews produced by the two strains on the two hosts. Approximately half of the amino acids found in the honeydew were at concentrations which were significantly lower than concentrations in the phloem sap. Honeydew from both hosts contain six additional amino acids. The major one was glutamine which may be used to expel nitrogen. Carbohydrates in phloem sap and honeydew were common transport sugars, like sucrose. Both honeydews contained trehalulose, a disaccharide not previously associated with insects. Both strains processed phloem sap and honeydew from both plants in the same manner, but the Florida strain produced significantly larger quantities of honeydew; it is therefore assumed to process more phloem sap. Since this strain has access to more phloem sap it also has access to more of the amino acids which are in short supply in the phloem sap of some plants allowing it to broaden its range.
76

Vegetative Propogation of Mexican Redbud, Larchleaf Goldenweed, Littleleaf Ash, and Evergreen Sumac by Stem Cuttings

Tipton, J. L. January 1989 (has links)
Effect of cutting age (weeks after budbreak) and IBA concentration on percent rooting of Mexican redbud, larchleaf goldenweed, littleleaf ash, and evergreen sumac were investigated. Maximum predicted percent rooting was 88% for cuttings of Mexican redbud taken 4 weeks after budbreak and treated with 21 gliter⁻¹ IBA, 99% for cuttings of larchleaf goldenweed taken 6 weeks after budbreak and treated with 16 gliter⁻¹ IBA, 86% for cuttings of littleleaf ash taken 16 weeks after budbreak and treated with 17 gliter⁻¹ IBA, and 24% for cuttings of evergreen sumac taken 16 weeks after budbreak and treated with 5 gliter⁻¹ IBA.
77

Response of Tall Fescue Turf to Applications of Sulfentrazone

Kopec, David M., Gilbert, Jeffrey J. 09 1900 (has links)
Applications of sulfentrazone were applied to 2.75" mowed tall fescue under hot-humid desert conditions to assess post application response. A uniform decrease in color occurred shortly after application at the 0.375 lb. AI/A rate. The effect was short lived and tended to be minimal in split application treatments. Leaf cupping/twisting was exacerbated from applications of sulfentrazone, especially at the 0.375 lb. AI/A rate. At 0.125 and 0.250 lb. AI/ rates, the leaf cupping was much less noticeable. Percent plot showing the leaf cupping symptoms was also rate dependent and generally ranked with degree of effect. Leaf cupping dissipated rapidly after 14 days after treatment. Color changes were minor, while leaf cupping was the more noticeable symptom response on tall fescue from applications of sulfentrazone.
78

Response of Perennial Ryegrass under Desert Conditions to Applications of Sulfentrazone Herbicide

Kopec, David M., Gilbert, Jeffrey J. 09 1900 (has links)
Sulfentrazone was applied to perennial ryegrass turf as single applications at 0.125, 0.250 and 0.375 lb. AI/A, and split application combinations of 0.125/0.125, 0.250/0.250 and 0.375/0.125 AI/A. Respective treatments were applied on June 28 and July 31, 1996. Sulfentrazone caused a decrease in turfgrass color, which was most noticeable at the 0.375 lb. AI/A rate. Decreases in color were generally dependent on application rate. Sulfentrazone caused a slight "pocking" of the turf, which resulted from leaf twisting/cupping. This injury was most evident at seven days after the first application. There was no foliar burning or uneven discoloration however. The turf exhibited a lesser amount of discoloration and injury following the second (split) application.
79

Response of Common Bermudagrass Turf to Applications of Sulfentrazone

Kopec, David M., Gilbert, Jeffrey J. 09 1900 (has links)
Sulfentrazone was applied in single applications at the rates of 0.125, 0.250 and 0.375 lbs. AI/A, and after 30 days in split rate combinations of 0.125/0.125, 0.250/0.250 and 0.125/0.375 lbs. AI/A. Turfgrass color scores were slightly diminished form sulfentrazone characterized by a lighter uniform color change on mowed common bermudagrass. The response was generally rate dependent. Imazaquin caused a light green turf to develop while halsulfuron had no effect. After the first application was made, sulfentrazone treated turfs exhibited leaf twisting/cupping effects at 3 and 7 days after treatment. The degree of effect was also rate dependent. To the lay person, twisting was noticeable only for a short time at the 0.375 lb. AI/A rate. At two weeks after treatment, there was a trace amount of leaf sheath necrosis at the base (older leaves) of common bermudagrass stolons. This was negligible and short lived. At the rates tested in this initial preliminary test, it appears that common bermudagrass seems to be tolerant of sulfentrazone.
80

Response of Tall Fescue to R.P.-EXP31130A and R.P.-EXP31598A

Kopec, David M., Gilbert, Jeffrey J., Kerr, Darren E. 09 1900 (has links)
EXP31130A and EXP31598A were applied as repeat applications on June 5 and July 23, 1997 to tall fescue turf maintained at 3.0 inches. Application rates were 0.18 and 0.36 lbs. AI/A (31130A) and 7.0 and 14.0 fl. oz/prod/A (31598A). Each treatment was applied with and without Sequestrene 338 iron chelate, at the rate of 0.1 oz/m ². Untreated and iron-only controls were included in the test. Neither herbicide compound (either with of without iron) caused discoloration, leaf tip burn, sheath necrosis, or blotchy colored turf at the rates and timing applications performed here for low maintenance tall fescue under desert summer conditions. EXP31598A herbicide, when applied without iron to tall fescue turf, exhibited acceptable levels of turfgrass color at all times when applied at the 7 ounce/prod./acre rate. EXP31598A herbicide, when applied without iron to tall fescue turf, exhibited a lighter, but acceptable color turf, when applied at the 14 ounce/prod./acre rate. When iron was added, the 14 ounce/prod./acre rate of EXP31598A produced in general, a slightly darker turf than the same compound at the 7.0 ounce/prod./acre rate. Improved turf color resulted from the addition of iron at 0.1 ounce/m ² for tall fescue treated with EXP31130A. This occurred more so for turf treated at the low rate (0.18 lb. AI/A) than for turf treated at the high rate (0.36 lb. AI/A). The addition of iron to EXP31130A did not increase overall quality at either application rate of the herbicide. When iron was added (0.1 ounce/m ²), turfgrass quality was improved for EXP31598A, especially at the high application rate of 14 ounce/prod./acre.

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