• 1988 Tall Fescue Variety Trial

      Mancino, C. F.; Kopec, D. M.; Salo, L.; Bermudez, R.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
    • 1989 Tall Fescue Variety Trial

      Mancino, C. F.; Kopec, D. M.; Ralowicz, A. E.; Maricic, A.; Nelson, D.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      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.
    • Activity of Imazaquin for Purple Nutsedge Suppression Using Various Application Techniques

      Kopec, D. M.; Heathman, E. S.; Mancino, C. F.; Moharram, H. N.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      An experiment was devised to evaluate application technique, and elucidate the plant response (herbicidal activity) of imazaquin herbicide on single plants of purple nutsedge. Herbicide treated plants showed increased filleting and stunting 31 days after treatment. Soil treatments tended to increase herbicidal response. Imazaquin activity was minimized when the herbicide was not irrigated into the soil. Soil applied-imazaquin postponed the emergence of shoots from viable nutlets, but did not prevent emergence altogether.
    • Air-layering as a Method of Asexual Propagation of Mesquite

      Hagen, R. H.; Palzkill, D. A.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      Three 12-year-old Prosopis chilensis were successfully layered in spring and late summer. The best rooting occurred with 1 cm stems treated with either 5,000 or 15,000 ppm IBA. Air-layers treated with IBA had a higher rooting rate and better root quality than untreated air-layers.
    • Assessment of Application Rate and Formulation of Imazaquin Herbicide on Purple Nutsedge Suppression

      Kopec, D. M.; Heathman, E. S.; Mancino, C. F.; Moharram, H. N.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      A field test was implemented at Paradise Valley Country Club to investigate the effect of two rates of imazaquin (Image) herbicide (0.38 and 0.50 lbs ai /a) in both the granular (G) and emulsifiable concentrate formulation on purple nutsedge and common bermudagrass in a mixed stand (85 ± 20% nutsedge).
    • Branch Induction with Cytokinin to Improve Appearance and Increase Cutting Production of Jojoba

      Ravetta, D.; Palzkill, D. A.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      Treatment of jojoba plants with foliar sprays of benzyladenine (BA) alone, or in combination with gibberellin(4+7) (GA(4+7)) fatly increased branching frequency compared to untreated control plants and to plants from which all shoot tips were removed (pinched). Use of BA by itself resulted in an adverse reduction in intemode elongation. This was overcome in treatments which included GA(4+7) Use of GA(4+7) by itself resulted in reduced branching and abnormal shoot elongation. Pruning (pinching) of all shoot tips resulted in a slight increase in branching over untreated plants, but it had much less effect on branching than did treatments with BA. Results were very similar on two different clones tested.
    • 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.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      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.
    • Chemical Growth Retardant Effects on Easter Lilies

      Bailey, D. A.; Miller, W. B.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      Plants of Lilium longiflontm Thunb. 'Nellie White' recei,yed the following treatments during forcing: 1) control; 2-3) gne or two sprays of 50 mg-liter ancymidol 4-9) one or two sprays of 5, la, or 15 mg-liter XE-1019; or 10) one spray of 20 mg-liter XE-1019. All growth retardant treatments reduced plant height compared to controls. Plant height decreased linearly with increasing concentration of XE-1019 for both one- and two-spray treatments. High concentrations of XE-1019 delayed anthesis; ancymidol treatments did not. Individual corolla length was not affected by treatments. Treatments did not affect daughter bulb depletion or new daughter bulb growth. Total leaf area and leaf dry weight decreased as XE-1019 concentration increased; ancymidol treatments did not affect leaf area, but did reduce leaf dry weight. Leaf total soluble carbohydrate decreased with increasing concentration of XE-1019.
    • Chemical Height Control of Florists' Hydrangeas

      Bailey, D. A.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      XE-1019 (2 foliar sprays of 10, 2Q or 30 mg-liter⁻¹) was applied to plants of Hydrangea macrophylla Ser. 'Rose Supreme' during greenhouse forcing. Doses applied resulted in excessive reductions in shoot elongation and inflorescence diameters and delayed anthesis. Shoot growth was reduced with increasing XE-1019 concentration. Shoot length was reduced 46 %; stem dry weight was reduced 31 %; leaf area per shoot was reduced 44 %; inflorescence height was cut by 45 %; and inflorescence mass was reduced 48% with the 30 mg-liter⁻¹ XE-1019 treatment. Specific leaf weight increased with increased XE -1019 concentration (192% increase with the 30 mg-liter⁻¹ treatment) resulting in thicker leaves at anthesis. XE-1019 is an effective height control agent for florists' hydrangeas, and shows significant activity at very low (less than 0.2 mg a.i. per plant) doses.
    • Controlling Hybrid Lily Plant Height with Ancymicol and XE-1019

      Bailey, D. A.; Miller, W. B.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      Plants of Lilium speciosum hybrids '101' and '298' received one 125 ml soil drench containing 1-3) 0, 0.125, or 0.25 mg ai. ancymidol per pot; or 4-6) 0.05, 0.10, or 0.15 mg a.i. XE-1019 per pot. Ancymidol treatments were less effective in controlling plant height (11 % and 16 % reduction of control plant height) than were XE-1019 treatments (18 %, 26 %, and 34 % reduction of control plant height). Treatments did not affect days from planting to visible bud; days from planting to anthesis of the first flower per inflorescence; the total number of flowers per inflorescence reaching anthesis; or the number of aborting buds per inflorescence. The treatments investigated allowed for rapid production of plants having a commercially acceptable height without a reduction in flowering quality.
    • Correcting Iron Chlorosis in Pyracantha

      Doerge, T. A.; Gibson, R.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      The alkaline nature of most Arizona soils contributes to widespread iron deficiency in exotic ornamental plants, such as pyracantha. An experiment was conducted in 1987 to evaluate the effectiveness of two soil-applied iron fertilizers (FeEDDHA chelate and a jarosite-type iron silicate, Ironite\) and three rates of foliar- applied FeEDDHA in controlling iron chlorosis symptoms in established pyracantha vines. Soil-applied FeEDDHA was the most effective in reducing iron chlorosis symptoms, followed by the foliar chelate treatments. The iron silicate material had no significant effect on iron chloroses symptoms compared to the untreated control. Both soil and foliar applications of FeEDDHA chelate made in the fall can effectively control iron chlorosis symptoms in established pyracantha.
    • Determining Optimum Length of Bulb Cold Storage for Oriental Hybrid Lilies in Arizona

      Miller, W. B.; Bailey, D. A.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      Bulbs of three varieties of oriental hybrid lilies were stored at 4 °C for 6 to 12 weeks prior to greenhouse forcing at 18 °C night temperature. Increasing duration of storage reduced the number of days to shoot emergence, visible flower buck and anthesis for each variety. The number of days from planting to anthesis ranged from 70 to 102 and varied with cultivar and storage duration. Increasing durations of storage had no commercially significant effect on the number of flowers reaching anthesis, number of leaves or aborted flower buds. The varieties used in this study flower earlier than commercially established cultivars and may be successfully forced in Arizona for early spring holidays.
    • Effect of Salinity Stress on Development of Pythium Blight of Agrostis palustris

      Rasmussen, S. L.; Stanghellini, M. E.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      Salinity stress predisposed cultivar Penncross creeping bentgrass to cottony blight caused by Pythium aphanidennatum at two temperature regimes. At 25-32 C, complete necrosis of all inoculated plants occurred at electrical conductivity (Ec) levels from 4.3-7.1 ds/m in 2 days, whereas at Ec levels of 0.5-2.8 ds/m death occurred within 3 days. At 25-27 C, complete necrosis of all inoculated plants occurred at Ec levels from 4.3-7.1 ds /m within a period of 5 days; no death was observed in control or inoculated plants at an Ec level of 0.5 ds/m. Increased salinity levels apparently affected the bentgrass rather than P. aphanidermatum. Mycelia' growth rate of the fungus was increased only slightly by salinity levels up to 7.1 ds/m. Zoospore production of P. aphanidermatum and two other species of Pythium decreased with increasing salinity levels up to 7.1 ds/m; production was completely inhibited at 14.2 ds/m.
    • Effects of Gypsum on a Wastewater Irrigated Turfgrass Soil

      Mancino, C. F.; Kopec, D. M.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      Secondarily treated wastewater is used extensively in the southwestern United States for turfgrass irrigation, but deterioration in soil quality can occur from sodium (Na) delivered by this water. Application of gypsum (CaSO₄2H₂O) at 2 240 kg ha⁻¹ yr⁻¹ is often recommended to control the Na. Research to determine if this rate is effective on effluent -irrigated turfgrass sites is lacking. A 2-yr study was carried out on a golf course fairway (typic tomf7uvent soil) with a 10 yr history of effluent irrigation and elevated Na levels (800 mg kg⁻¹). Four rates of gypsum (0, 2 240, 4 480, and 8 960 kg ha⁻¹) were surface applied in November 1986 and 1987. Soil samples were collected every 3 months after treatment (MAT) and analyzed for Ca (total and water - soluble (WSCa)), Mg, K, Na, SO₄⁻²-S (S), pH, and electrical conductivity (EC). Results showed elevated WSCa and S levels 3 and 6 MAT in both years. The two highest rates resulted in elevated S levels 12 MAT. During both years, gypsum at the two higher rates decreased Na levels within 3 MAT. The lowest application rate did not reduce Na levels until 12 MAT in 1987 and its effects were not as great. Following the second annual application, the 2 240 kg ha⁻¹ rate was as effective as the higher rates in reducing Na levels 6 and 12 MAT. Total Ca levels were not affected by gypsum but Mg and K levels did decrease. In both years, a temporary increase in EC and decrease in pH occurred after gypsum treatment. It appears that gypsum at 2 240 kg ha⁻¹yr⁻¹ can be as effective as higher application rates in reducing Na in effluent-irrigated turf soil but only after two applications.
    • Effects of XE-1019 Spray Concentration of Chrysanthemums

      Bailey, D. A.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      Plants of Chrysanthemum moifolium Ramat. 'Ovaro' received 0, 10, 20, or 30 mg-liter ⁻¹ XE-1019 applied as a 204 ml-m⁻² foliar spray. Treatments did not affect time from start of short days to bloom or inflorescence height lunge. Inflorescence height and inflorescence display diameter both were reduced with increasing concentration of XE-1019.
    • Estimating Turfgrass Water Use with AZMET

      Brown, P.; Kopec, D.; Mancino, C.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      The Arizona Meteorological Network provides weather-based estimates of reference evapotranspiration (ETo) for much of southern, central and western Arizona. A simple 3-step procedure to convert ETo data into reliable estimates of turfgrass water use is described The procedure requires that AZMET ETo values be multiplied by a correction factor known as a crop coefficient (Kc). The selection of the Kc depends on the type and height of the turfgrass as well as desired turf quality. The procedure is well adapted for use on computers.
    • Ethylene-Induced Flower Bud Abortion in Easter Lily is Inhibited by Silver Thiosulfate

      Mason, Michael R.; Miller, William B.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      Flower bud abortion, or "blasting" was shown to be at least partially caused by treating plants with ethephon, a chemical that releases ethylene. In floricultural greenhouses, ethylene could accumulate to levels that could induce commercially significant levels of flower bud injury. Silver thiosulfate (STS) was shown to be a potent inhibitor of ethephon injury. STS at (1 to 2 mM) could be applied as early as the visible bud stage (approximately 5 to 6 weeks before flowering) without phytotoxic effects. Using current silver prices, the material cost for our treatment is less than 0.4 cents per plant. Based on these results, a preventative STS application could potentially reduce much of the flower bud abortion seen in commercial greenhouses.
    • Evaluation of Cold Storage for Unrooted Jojoba Cuttings

      Palzkill, D. A.; El-Serafy, M.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1988)
      Jojoba stem tip cuttings were stored under refrigerated conditions of 34° and 42°F for up to 2 months with no loss in rooting potential. Rooting percent for cuttings of two clones which were rooted with no prior storage was 64.8%. Rooting after 7, 14, 28 and 56 days of storage was 81.7, 72.9, 71.7 and 81.2 %, respectively.
    • 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.; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      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.
    • The Golf Industry in Arizona: An Economic Summary

      Wade, James C.; Barkley, David; Kopec, David M. (College of Agriculture, University of Arizona (Tucson, AZ), 1989)
      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.