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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.
61

1989 Tall Fescue Variety Trial

Mancino, C. F., Kopec, D. M., Ralowicz, A. E., Maricic, A., Nelson, D. January 1989 (has links)
Tall fescue is a very heat and drought tolerant, cool season turf, which can remain green throughout the year in the arid Southwest. Data are lacking on the performance of tall fescue varieties in this location. Sixty-five tall fescue entries were established in November 1987 and their performance as a home-lawn turf rated for quality, color, density, percent ground cover, pest incidence and water use. All varieties performed very well during the first seven months of 1989, but a decline in August quality was observed during summer monsoons mainly due to the incidence of large brown patch (Rhizoctonia solani L.) and record-setting high temperatures. Turf still showed signs of stress by mid-September. Turfgrass irrigation water use from 1 January to 23 September totalled 43.3 inches (1100.5 mm) and averaged 63 % of predicted evapotranspiration.
62

Irrigation of Turfgrass with Secondary Municipal Sewage Effluent: Soil and Turf Aspects

Hayes, A. R., Mancino, C. F., Forden, W. Y., Kopec, D. M., Pepper, I. L. January 1989 (has links)
This field experiment evaluated the use of secondary municipal sewage effluent for irrigation of two turfgrass species. In April 1987 common bermudagrass (Cynodon dactylon L. Pers.) was seeded to a gravelly sandy loans soil and maintained under fairway conditions. Perennial ryegrass (Loliman perenne L.) was overseeded in the fall to maintain an actively growing turf. Plots were irrigated identically with either effluent or potable water. Soil and irrigation water samples were collected periodically and analyzed for pH, electrical conductivity (EC), sodium (Na), calcium + magnesium (Ca +Mg), bicarbonates (HCO₃), nitrogen (N), phosphorus (P) and potassium (K). Effluent water was found to contain a higher sodium absorption ratio (SAR), EC and greater concentrations of all the above elements with the exception of pH. Effluent irrigation lead to significantly lower seed germination and resulted in higher EC, Na, nitrate- nitrogen (NO₃-N), P and K concentrations in soils. Turf quality was assessed by visual evaluation under four N fertilization rates in each irrigation regime. Established effluent irrigated turf did not show signs of osmotic stress with a 15-20% leaching fraction and responded to the nutrient content of this water during periods of higher irrigation rates. However, no single fertilization rate or irrigation regime consistently produced a superior turf quality. Secondary municipal sewage effluent was used successfully for turf irrigation but the greater EC, Na and nutrient content of the water need to be considered by the turf professional making management decisions.
63

Influence of pH 11 Water on Termiticide Degradation in Arizona

Baker, Paul B. 09 1900 (has links)
Termites continue to be Arizona’s number one urban pest. Factors that influence the persistence of termiticides are constantly under investigation. High pH has been identified as a potential concern for persistence in termiticides. I studied the influence of pH 11 water on five termiticides applied to commercial ABC fill 10 months post-treatment. In general, the addition of pH 11 water had little influence on termiticide persistence under Arizona conditions. Initially plots treated with Ph 11 water had higher residues than those that did not receive the treated water; over time these differences diminished.
64

An Update on Termiticide Degradation in Arizona Soil

Baker, Paul B. 09 1900 (has links)
Termiticide applications are the standard practice in the pest control industry to protect structures from the invasion of termites. However, information related to termiticide persistence is lacking. In 2 field trials, soil residues analysis were carried out to determine degradation among existing and candidate termiticides in 3 different chemical classes. Plots were established to simulate industry standards for the application of termiticides. Study 1 termiticides tested were Dragnet FT (permethrin, 0.5% and 0.25%;), Prevail FT (cypermethrin, 0.25%;), Biflex FT (bifenthrin, 0.06%;), Fury TC (zeta-cypermethrin, 0.125%;) Premise 75 (imidacloprid, 0.05%,), Dursban TC (chlorpyrifos, 1% and 0.75%) and the untreated check. In Study 2 termiticides tested were DeltaGard SC (deltamethrin 0.075%, 0.125% and 0.25%); Dragnet FT (permethrin 0.5%;)and the untreated checks. In study 1, in general, all termiticides showed more degradation in the exposed plots than those covered by the concrete slab. In the exposed plots, specifically in the 4th year, four of the eight treatments had no residues In comparison, the covered plots had only 1 treatment, with no residues. In general the pyrethroids of permethrin at 0.25% and 0.5% along with bifenthrin at 0.06% held up longer than the organophosphate chlorpyrifos or imidacloprid the chloronicotinyl compound. Study 2, after one year, the exposed plots showed a slightly greater degradation than the covered plots. However, due to plot-to-plot variation no conclusions can be drawn from the data, other than the permethrin plots showed less than 40% remaining in any plot.
65

Seed Propagation of Cordia boissieri and Cordia parvifolia

Schuch, Ursula K., Davison, Elizabeth, Kelly, Jack 09 1900 (has links)
Cordia boissieri and Cordia parvifolia are plants commonly used in landscapes in the Southwest. Although they are available in the nursery trade, Cordia species are recalcitrant to germinate from seeds. The objective of the study was to determine a reliable propagation protocol for each species. Germination percentages for Cordia boissieri of 70 to 100% were obtained when seeds were stratified under warm conditions before germination. However, with prolonged storage seeds lose viability and age of the seed and seed storage conditions need further investigation. Seeds of Cordia parvifolia collected from local sources had low viability and did not germinate in response to several different seed treatments.
66

Comparison of Two Rates and Two Formulations of Imazaquin for Control of Purple Nutsedge

Kopec, David M., Jensen, D. P., Gilbert, Jeffrey J. 09 1900 (has links)
Purple nutsedge (Cyperus rotundus) is a major warm season weed in turfgrass, landscape and agricultural settings. It’s long term persistence is achieved in part by (1) the production of tubers with numerous growing points (2) the ability to produce multiple plants from basal bulbuls at the soil level and (3) the tolerance to defoliation and/or soil cultivation. In turf, purple nutsedge can tolerate almost any mowing regime, and is competitive (in it's growth habit) with turfgrasses. Imazaquin (IMAGE) herbicide has been commercially available in the turfgrass market for almost 12 years for use in warm season turfgrasses for the control of purple nutsedge. Research conducted in the late 1980's at the University of Arizona showed that Image (EC formulation) provided adequate control of purple nutsedge when (1) multiple applications were applied 25 days apart (2) at the 0.50 lb. ai./a rate. In this scenario 98% nutsedge control was achieved (on 100 % nutsedge plots, mowed weekly at 2.5 inches). Repeat applications were still necessary after regrowth (presumably from growing points from underground nutlets). These results were achieved using the 1.5 EC (emulsifiable concentrate formulation). A new test was conducted in 1999, evaluating both the 1.5 EC and 70 DG (dispersible granule) formulations applied at two rates (0.375 lb. ai./a. and 0.50 lb. ai./a). Mean percent weed control on the three evaluation dates of August 17, August 29 and September 16 ranged from 25% to 32%, 50% to 68% and 55% to 75%, respectively. These dates represent the time intervals of 18 DAT/1, 30 DAT/1 and 17 DAT/2. On all three evaluations dates (where measured), the degree of injury, color and percent nutsedge infestation level was significant for the overall "treatment" effect at P=0.05, or less. (Tables 1,2). Actual percent weed control (based on the mean of control plots) was significant on August 29 (30 DAT/1) and on September 16 (17 DAT/2:47 DAT/1). Maximum weed control of 75% was achieved by the EC @ 0.50 lbs. ai./a. at 17 days after the second application. Percent weed control for the DG @ 0.50 lbs. ai./a. was greatest (61%) at that time also.
67

Response of Poa annua to Post-Emergence Application of Sulfentrazone Herbicide

Kopec, David M., Gilbert, Jeffrey J. 09 1900 (has links)
Poa annua (annual bluegrass) is a major weed problem in winter turfs. It is a cosmopolitan and well adapted weed in most turfgrass settings. Cultural management programs to control or eliminate Poa annua are either limited or unsuccessful. Sulfentrazone herbicide was applied to perennial ryegrass turf (as overseeded bermudagrass) which had high levels of Poa annua infestation (45%-75%) at 0.125, 0.250 and 0.375 lb. AI/A. There was essentially a limited response of Poa annua to Sulfentrazone at these rates when applied on March 7, 1997. EMBARK LITE (Mefluidide) was applied once at 0.125 lb. AI/A and caused some initial discoloration to the turf at 10 DAT. At 25 DAT percent control of Poa annua (seed heads) reached 90% or greater which declined to 58% on April 15 (40 DAT). Turfgrass color was enhanced from the single application of Mefluidide at 25 and 40 DAT on golf course rough turf maintained at a mowing height of 1.50 inches. Sulfentrazone exhibited minimal or no effect on Poa annua when applied as a post emergence treatment.
68

Drought Tolerance of Twenty one Saltgrass (Distichlis) Accessions Compared to Bermudagrass

Pessarakli, Mohammed, Marcum, K. B., Kopec, David M. 09 1900 (has links)
Fourteen (14) Arizona accessions and 7 Colorado accessions of Saltgrass (Distichlis spicata), collected from Arizona and Colorado and 1 Bermudagrass (Cynodon dactylon), cultivar Midiron (check), were studied in a greenhouse to evaluate their growth responses in terms of shoot dry weights and percentage of visual green under drought stress conditions. Plants were grown under normal (daily watering and weekly fertilizer application) for one year for complete establishment. Then, the plants were deprived from water for four months (January 5, 2001 - May 5, 2001). Plant clippings were harvested weekly, oven dried at 60 °C, and the dry weights were recorded. At each harvest, percentage of green cover were also estimated and recorded. After the last harvest, plants were re-watered to assess and compare the percent of recovery. Overall, the results (both shoot dry weights and the percent of the visual green) show that the A138 and A137 (Arizona accessions) were the best accessions and the C66 (Colorado accession) was the worst. Both the shoot dry weights and the percent of visual green cover decreased as the drought period progressed. In general, most of the saltgrass accessions were more tolerant to drought stress than the bermudagrass.
69

Control of Wild Celery in Low Maintenance Bermudagrass Turf.

Kopec, David M., Jensen, David M., Gilbert, Jeffrey J., Liddel, Steven B. 09 1900 (has links)
Herbicides applied for post-emergence control of wild parsley differed in turf injury and weed control. All products tested required multiple applications (21 days apart) to attain acceptable weed control levels. Weedone (2, 4-D) has the quickest, highest, and longest lasting amount of weed control. Weedone (2, 4-D) caused minimal injury to the common bermudagrass turf. Bromoxynil at the low rate of 2.0 lbs. ai/a caused minimal injury to the turf, but provided low levels of weed control. Bromoxynil at the high rate of 3.0 lbs. ai/a caused considerable injury to the turf and moderate to high weed control for about one month, followed by weed recovery. MCPP caused slight initial injury to common bermudagrass and moderate to good weed control (71%-92%) from 7 to 35 days after the second treatment. Weed control was slower to achieve than that of the Weedone treatments. Confront herbicide (trichlopyr and clopyralid) caused slight to moderate initial injury to the turf (more so at 2.0 than at 1.0 pint/product/acre) as well as noticeable necrosis and decreased color of the common bermudagrass up to 21 days after the second application. Confront at the 2.0 pint/acre rate reached weed control levels of 90%-97% at 21 and 35 days after the second application, respectively. At the low rate of 1.0 pint/acre, a maximum of 83% weed control was achieved at the close of the test. Quadmec (applied three weeks later at each respective application date than all other treatments) produced moderate necrosis in the bermudagrass after the initial application, which eventually recovered. However, the turfgrass color was lower in rank (lighter) than most other treatments and was similar to that of the untreated controls. Quadmec achieved 96% control by the close of the test on July 2, 1999 (14 days after the second application). All treatments include 0.5% v/v Silwet surfactant. When applied alone, Silwet produced a small level of weed control, which peaked at 36% at 14 days after the second treatment.
70

Evaluation of Timing Applications of Ethephon and Trinexepac-Ethyl for Seed Head Suppression of Poa annua

Kopec, David M., Gilbert, Jeffrey J., Pessarakli, Mohammed 09 1900 (has links)
Seed head production from Poa annua is problematic on winter turfs, whether they are overseeded or not. Flowering culms are unsightly, prevent a uniform surface, and insure a continuous crop of seeds for the future. A field test was conducted to evaluate the effects of PROXY and a PROXY/PRIMO PGR tank mix for seed head control. Treatments were applied on three different dates in order to evaluate the degree of response of treatments and help define treatment window applications for future programs. PROXY when applied alone at 5 ounces/product/M produced a maximum of 60% seed head control at 26 days after a single application on February 15, and 83% seed head control at 27 days after a single application on March 1. A tank mix of PROXY/PRIMO (5.0/0.25 ounces/product/M) generally produced greater seed head control than PROXY alone. The tank mix produced seed head control effects quicker, greater, and longer than PROXY alone. Seed head suppression and percent seed head control was greatest when products were applied initially on either February 15 or March 1, 2001. PROXY/PRIMO produced the darkest color turf when applied on either February 15 or March 1. At least three tank mixes seem to be needed, applied monthly to suppress/control seed heads throughout the winter/spring season.

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