Abstract:
The invention relates to a method of improving turfgrass quality comprising applying an effective amount of a composition containing a phthalocyanine to the turfgrass in the substantial absence of phosphorous acid, monoalkyl esters of phosphorous acid, or salts thereof.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to methods of improving turfgrass quality and relieving stress on turfgrass and to compositions suitable therefor.  
         [0002]     U.S. Pat. No. 5,599,804 describes a method of combating fungi and enhancing turf quality in turfgrass by applying in specific ratios certain phthalocyanines in combination with phosphorous acid or an alkaline earth metal salt thereof or with certain monoester salts of phosphorous acid. U.S. Pat. No. 5,643,852 describes a method of enhancing turf quality in turfgrass by applying in specific ratios certain phthalocyanines in combination with (i) phosphorous acid or an alkaline earth metal salt thereof or certain monoester salts of phosphorous acid and (ii) certain ethylene bisdithiocarbamate contact fungicides. U.S. Pat. No. 5,336,661 describes a method of treating bentgrass and enhancing turf quality by applying in specific ratios (i) certain monoester salts of phosphorous acid and (ii) a metallic ethylene bisdithiocarbamate contact fungicide. This patent also describes a specific composition containing a combination of aluminum tris(O-ethylphosphonate) (fosetyl-al) and a manganese-zinc ethylene bisdithiocarbamate complex (mancozeb) used in a form (i.e., FORE fungicide) believed to have contained an unknown amount of the phthalocyanine compound Pigment Blue 15.  
         [0003]     It has now unexpectedly been found that the quality of turfgrass can be improved by applying certain phthalocyanines in the substantial absence of the additional components mentioned above.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention provides a method of improving turfgrass quality comprising applying an effective amount of a composition containing a phthalocyanine to the turfgrass, with the proviso that the composition does not include an effective amount of phosphorous acid or a salt thereof or of monoalkyl esters of phosphorous acid or salts thereof and preferably also does not include metallic ethylene bisdithiocarbamate contact fungicides or other fungicides.  
         [0005]     The present invention further provides a composition for improving turfgrass consisting essentially of an effective amount of a turfgrass-improving amount of a phthalocyanine, at least one dispersant acceptable for use in turfgrass, at least one carrier acceptable for use in turfgrass, and, optionally, water. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]      FIG. 1  illustrates the effect of phthalocyanine and fungicide applications on Penncross creeping bentgrass turf quality at high temperature treatment.  
         [0007]      FIG. 2  illustrates the effect of phthalocyanine and fungicide applications on net photosynthetic rate of Penncross creeping bentgrass at high temperature treatment.  
         [0008]      FIG. 3  illustrates the effect of phthalocyanine and fungicide applications on chlorophyll content of Penncross creeping bentgrass at high temperature treatment.  
         [0009]      FIG. 4  illustrates the effect of phthalocyanine and fungicide applications on chlorophyll photochemical efficiency of Penncross creeping bentgrass at high temperature treatment.  
         [0010]      FIG. 5  illustrates the effect of phthalocyanine and fungicide applications on carotenoids content of Penncross creeping bentgrass at high temperature treatment.  
         [0011]      FIG. 6  illustrates the effect of phthalocyanine and fungicide applications on shoot growth rate in height of Penncross creeping bentgrass at high temperature treatment.  
         [0012]      FIG. 7  illustrates the effect of phthalocyanine and fungicide applications on root and canopy shoot biomass of Penncross creeping bentgrass at high temperature treatment.  
         [0013]      FIG. 8  illustrates the effect of phthalocyanine and fungicide applications on root mortality of Penncross creeping bentgrass at high temperature treatment.  
         [0014]      FIG. 9  illustrates the effect of phthalocyanine and fungicide application on tiller density of Penncross creeping bentgrass at high temperature treatment. In the figures by the term “Pigment” is meant Pigment Blue 15.  
         [0015]      FIG. 10  illustrates the effect of phthalocyanine application on Penncross creeping bentgrass color.  
         [0016]      FIGS. 11 and 12  illustrate the effect of phthalocyanine and fungicide applications on the color of Penncross creeping bentgrass. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]     Suitable phthalocyanines for use according to the invention include metal-free phthalocyanines or metal-containing phthalocyanines. The metals of metal-containing phthalocyanines are typically transition metals such as copper, silver, gold, zinc, cadmium, mercury, scandium, yittrium, lanthanum, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium, iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel, palladium, and platinum. Copper, nickel, cobalt, iron, and zinc phthalocyanines are preferred, with copper phthalocyanines being particularly preferred.  
         [0018]     Suitable substituted phthalocyanines may be substituted from 1 to 4 times on each isoindole group independently. Examples of suitable substituents for the isoindole groups of phthalocyanine dyes include but are not limited to halogen, unsubstituted or substituted lower alkyl, lower alkoxy, alkylamino, alkylthio, ammonium, sulfonato, sulfonato alkyl, sulfate, phosphate, phosphonate, and carboxylate. The ionic or ionizable substituents can have as counterions the alkali metals, preferably lithium, sodium, or potassium, the alkaline earth metals, preferably beryllium, magnesium, calcium, strontium, and barium, and various ammonium ions. By the terms lower alkyl and lower alkoxy are generally meant alkyl groups of from 1 to 6 carbon atoms and alkoxy groups of from 1 to 6 carbon atoms.  
         [0019]     Suitable phthalocyanines are commercially available and include but are not limited to Pigment Blue 16, Vat Blue 29, Pigment Blue 15, Heliogen Green GG, Ingrain Blue 14, Ingrain Blue 5, Ingrain Blue 1, Pigment Green 37, and Pigment Green 7. In one preferred embodiment, the phthalocyanine is Pigment Blue 15, also known as phthalocyanine blue.  
         [0020]     The compositions used according to the invention do not include effective amounts of phosphorous acid, monoalkyl esters of phosphorous acid, or salts thereof. Examples of such compounds to be excluded or substantially excluded are (i) compounds of the formula [HP(OR)O 2 ) − ] n  M n+  in which R is C 2 -C 4  alkyl, M is an alkali metal, alkaline earth, or aluminum atom, and n is an integer of from 1 to 3 equal to the valence of M, or (ii) phosphorous acid or alkaline earth metal salts thereof.  
         [0021]     Other compounds are also preferably excluded or substantially excluded from the present invention. For example, in one preferred embodiment, the compositions and methods of the invention do not include effective amounts of (i) phosphorous acid, monoalkyl esters of phosphorous acid, or salts thereof and (ii) metallic ethylene bisdithiocarbamate contact fungicides, especially manganese ethylene bisdithiocarbamate or manganese-zinc ethylene bisdithiocarbamate. In a second preferred embodiment, the compositions and methods of the invention do not include effective amounts of (i) phosphorous acid, monoalkyl esters of phosphorous acid, or salts thereof, (ii) the metallic ethylene bisdithiocarbamate contact fungicides mentioned above, and (iii) one or more other fungicides, particularly those selected from the group consisting of basic salts or hydroxides of copper (e.g., the oxychloride or oxysulphate), (tetrahydro)phthalimides (e.g., captan, captafol, or folpel), methyl(butylcarbamoyl)-2-benzimidazolecarbamate (benomyl), thiophanates such as dimethyl(1,2-phenylene)bis(iminocarbonothioyl)bis(carbamate) (thiophanate-methyl), tetrachloroisophthalonitrile (chlorothalonil), 3-(3,5-dichlorophenyl)-N-(1-methylethyl)-2,4-dioxo-1-imidazolidinecarboxamide(iprodione), 1-[2-(2,4-dichlorophenyl) 4 -propyl-1,3-dioxolan-2-yl methyl-1H-1,2,4-triazole (propiconazole), 1-(4-chlorophenoxy)-3,3-dimethyl-1(1H-1,2,4-triazol-1-yl)-2-butanone (triadimafon), 2-hydroxy-1,3,2-dioxaphospholanes, and β-hydroxy ethyl phosphites. In a third preferred embodiment, the compositions of the invention do not include effective amounts of the components (i) and (iii) mentioned above.  
         [0022]     The compositions used according to the invention preferably consists essentially of an effective amount of a phthalocyanine (preferably phthalocyanine blue) and more preferably consist of an effective amount of a phthalocyanine (preferably phthalocyanine blue), at least one dispersant, at least one carrier, and, optionally, water. The compositions may in one embodiment contain the phthalocyanine and water with no carrier. The compositions of the invention may consist essentially of a phthalocyanine compound and water. The compositions may also consist of a phthalocyanine compound and water.  
         [0023]     The compositions according to the instant invention generally contain from about 0.5 to about 95% of phthalocyanine by weight, preferably from 1% to 50%, more preferably from 2% to 35%. The remainder of the composition up to 100% comprises a carrier as well as various optional additives such as those hereafter indicated.  
         [0024]     By “carrier”, there is meant herein an organic or inorganic material, which can be natural or synthetic, and which is associated with the phthalocyanine and facilitates its application to the locus to be treated. This carrier is thus generally inert and should be agriculturally acceptable, especially on the contemplated or treated turfgrass. The carrier can be solid (e.g., clay, silicates, silica, resins, wax, fertilizers, and the like) or liquid (e.g., water, alcohols, ketones, oil solvents, saturated or unsaturated hydrocarbons, chlorinated hydrocarbons, liquefied petroleum gas, and the like).  
         [0025]     Among the many optional additives suitable for use in compositions of the invention include surfactants and other ingredients, such as dispersants, stickers, antifoam agents, antifreezing agents, dyestuffs, thickeners, adhesives, protective colloids, penetrating agents, stabilizing agents, sequestering agents, antiflocculating agents, corrosion inhibitors, pigments (other than those contemplated as an active ingredient for purposes of the invention), and polymers.  
         [0026]     More generally, the compositions of the invention can include all kinds of solid or liquid additives which are known in the art of crop protection and horticultural pest control treatments.  
         [0027]     The surfactants can be of the emulsifying or wetting type and can be ionic or non-ionic. Possible surfactants are salts of polyacrylic or lignosulfonic acids; salts of phenolsulfonic or naphthalenesulfonic acids; polycondensates of ethylene oxide with fatty alcohols or fatty acids or fatty amines or substituted phenols (particularly alkylphenols or arylphenols); ester-salts of sulfosuccinic acids; taurine derivatives, such as alkyl taurates; phosphoric esters; or esters of alcohols or polyoxyethylated phenols. When the spraying vehicle is water, the use of at least one surfactant is generally required because the active ingredients are not water-soluble.  
         [0028]     Dusting powders, granulates, solution, emulsifiable concentrates, emulsions, suspended concentrates and aerosols are also contemplated within the invention. The wettable powders according to the invention can be prepared in such a way that they contain from 1% to 95% by weight of the active material, and they normally contain, in addition to a solid support, from 0 to 5% by weight of a wetting agent, from 3 to 10% by weight of a dispersant and, when necessary, from 0 to 10% by weight of one or more stabilizers and/or other additives, such as penetration agents, adhesives or anti-clumping agents, colorants, etc. The compositions according to the invention can contain other ingredients, for example protective colloids, adhesives or thickeners, thixotropic agents, stabilizers or sequestrants, as well as other active materials known to have pesticidal properties, especially certain fungicides, acaricides, and insecticides.  
         [0029]     The present invention can be practiced with all turfgrasses, including cool season turfgrasses and warm season turfgrasses. Examples of cool season turfgrasses are bluegrasses ( Poa  spp.), such as Kentucky bluegrass ( Poa pratensis  L.), rough bluegrass ( Poa trivialis  L.), Canada bluegrass ( Poa compressa  L.), annual bluegrass ( Poa annua  L.), upland bluegrass ( Poa glaucantha  Gaudin), wood bluegrass ( Poa nemoralis  L.), and bulbous bluegrass ( Poa bulbosa  L.); the bentgrasses and redtop ( Agrostis  spp.), such as creeping bentgrass ( Agrostis palustris  Huds.), colonial bentgrass ( Agrostis tenuis  Sibth.), velvet bentgrass ( Agrostis canina  L.), South German Mixed Bentgrass ( Agrostis  spp. including  Agrostis tenius  Sibth.,  Agrostis canina  L., and  Agrostis palustris  Huds.), and redtop ( Agrostis alba  L.); the fescues ( Festucu  spp.), such as red fescue ( Festuca rubra  L. spp.  rubra ), creeping fescue ( Festuca rubra  L.), chewings fescue ( Festuca rubra commutata  Gaud.), sheep fescue ( Festuca ovina  L.), hard fescue ( Festuca longifolia  Thuill.), hair fescue ( Festucu capillata  Lam.), tall fescue ( Festuca arundinacea  Schreb.), meadow fescue ( Festuca elanor  L.); the ryegrasses ( Lolium  spp.), such as annual ryegrass ( Lolium multiflorum  Lam.), perennial ryegrass ( Lolium perenne  L.), italian ryegrass ( Lolium multiflorum  Lam.); and the wheatgrasses ( Agropyron  spp.), such as fairway wheatgrass ( Agropyron cristatum  (L.) Gaertn.), crested wheatgrass ( Agropyron desertorum  (Fisch.) Schult.), and western wheatgrass ( Agropyron smithii  Rydb.). Other cool season turfgrasses include beachgrass ( Ammophila breviligulata  Fern.), smooth bromegrass ( Bromus inermis  Leyss.), cattails such as Timothy ( Phleum pratense  L.), sand cattail ( Phleum subulatum  L.), orchardgrass ( Dactylis glomerata  L.), weeping alkaligrass ( Puccinellia distans  (L.) Parl.) and crested dog&#39;s-tail ( Cynosurus cristatus  L.).  
         [0030]     Examples of warm season turfgrasses include Bermudagrass ( Cynodon  spp. L. C. Rich), zoysiagrass ( Zoysia  spp. Willd.), St. Augustine grass ( Stenotaphrum secundatum  Walt Kuntze), centipedegrass ( Eremochloa ophiuroides  Munro Hack.), carpetgrass ( Axonopus affinis  Chase), Bahia grass ( Paspalum notatum  Flugge), Kikuyugrass ( Pennisetum clandestinum  Hochst. ex Chiov.), buffalo grass ( Buchloe dactyloids  (Nutt.) Engelm.), Blue gramma ( Bouteloua gracilis  (H.B.K.) Lag. ex Griffiths), seashore  paspalum  ( Paspalum vaginatum  Swartz) and sideoats grama ( Bouteloua curtipendula  (Michx. Torr.). Cool season turfgrasses are generally preferred for treatment according to the invention. More preferred is bluegrass, bentgrass and redtop, fescue, and ryegrass. Bentgrass is most preferred.  
         [0031]     In general the rate of application at the locus is from 0.001 to 10 kilograms of phthalocyanine per hectare (kg/ha), preferably from 0.01 to 2 kg/ha, more preferably from 0.1 to 1 kg/ha, most preferably from 0.2 to 0.8 kg/ha. The compositions of the invention are applied by known methods.  
         [0032]     The following examples further illustrate details for the method and compositions of this invention. The invention, which is set forth in the foregoing disclosure, is not to be limited either in spirit or scope by these examples. Those skilled in the art will readily understand that known variations of the conditions of the following procedures can be used.  
       EXAMPLES  
     Example 1  
       [0033]     The following test methods were used to compare the effectiveness of phthalocyanine compositions according to the invention with known compositions. The following compositions were used in the experiments: Pigment Blue 15, also known as copper phthalocyanine, was used alone. A mixture of Pigment Blue 15 and fosetyl-al was used as the commercially available product Chipco® Signature™ fungicide from Bayer Environmental Science, Montvale, N.J. The compound fosetyl-al was used as Chipco® Aliette® WDG fungicide available from Bayer Environmental Science, Montvale N.J.  
         [0034]     Seeds of “Penncross” creeping bentgrass were sown in polyvinyl chloride (PVC) tubes (10 cm in diameter and 20 cm in length) filled with coarse sand. Plants were kept in a growth chamber for 90 days before treatment stated to allow root and canopy establishment. The daily temperature in the growth chamber was 20/16° C., the photosynthetic photon flux density was 400 μmol m −2  s −1 , and the photoperiod was 12 hours/day. Turf was mowed twice weekly at 4 mm with scissors, irrigated every other day until there was free drainage from the bottom of tubes, and fertilized weekly with 40 ml full-strength Hoagland&#39;s nutrient solution (Hoagland and Amon, 1950). Insecticide was applied to kill whitefly when necessary.  
         [0035]     Two treatments were conducted in the experiment. A high temperature treatment was maintained at 35/30° C. (day/night temperatures) and an optimum temperature treatment of 20/16° C. was used as temperature control. Signature fungicide and Aliette fungicide were each applied to the foliage in each treatment biweekly at the rate of 4 oz./1000 sq. ft. (118 mL/92.9 m 2 ) for Signature fungicide and Aliette fungicide; and Pigment Blue 15 was applied to the foliage in each treatment biweekly at the rate of 6.92 g/1000 sq. ft. (92.9 m 2 ), in order to roughly approximate the amount of Pigment Blue 15 being applied in each plot. Water alone was used as a non-fungicide control. (Treatments were applied only to plants at high temperature and not to control plants.) When treatments started, half of plants were sprayed 4 weeks before the high temperature treatment (i.e., as a pretreatment) and half of plants were sprayed at the same time of high soil temperature started (i.e., no pretreatment). Each treatment had 5 replications.  
         [0036]     Measurements were made at 1 week after treatments were applied. Turf quality was visually rated at the scale from 0 to 9 according to the density, greenness, and uniformity of the grass, with 0 being the worst and 9 being the best.  
         [0037]     Canopy net photosynthetic rate was measured as described below using a Li-6400 portable photosynthesis system (available from LiCor, Lincoln, NB).u  
         [0038]     For determination of the biomass, samples of shoots and roots at the end of each experiment were cleaned and dried at 80° C. in an oven for 72 hours. The dry weight of shoots and roots were used to indicate biomass of shoots and roots.  
         [0039]     Chlorophyll and carotenoids were extracted by soaking 50 mg fresh shoots in 20 ml dimethyl sulfoxide (DMSO) in the dark for 72 h. Absorbance of each extractant at 663 nm, 645 nm, and 470 nm was used to determine chlorophyll content using the formula of Amon (1949) and carotenoids content using the formula of Lichtenthaler and Wellburn (1983) Canopy photochemical efficiency was estimated by measuring chlorophyll fluorescence (Fv/Fm) using plant photosynthesis efficiency analyzer (available from ADC Bioscientific Limited, Herts, England).  
         [0040]     Root mortality was measured using the method of Knievel (1973) with modification. Samples of 0.5 g clean fresh roots were incubated with 10 mL 0.6% 2,3,5-triphenyltetrazolium chloride (in 0.05 M phosphate buffer, pH 7.4) for 24 h in the dark at 30° C. Roots were then rinsed twice with deionized water. Formazan was extracted from roots twice with 95% ethanol at 70° C. for 4 hour. The combined extractant from the two extractions was adjusted to a final volume of 20 mL with 95% ethanol. Absorbance at 490 nm was used to determine root mortality.  
         [0000]     Test Results  
         [0000]     A. Turf Quality  
         [0041]      FIG. 1  illustrates the effect of fungicide application on Penncross creeping bentgrass turf quality at high temperature treatment. Data are shown as mean±sd. Arrow indicates the date of first fungicide application.  
         [0042]     The quality of plants at the control temperature was maintained at high level during the entire experimental period ( FIG. 1 ). Heat stress reduced turf quality beginning 2 weeks after high temperature. For the plants with pretreatment ( FIG. 1 ), turf quality was highest at the application of Pigment Blue 15, followed by application of Signature fungicide and Aliette fungicide, water application showing the lowest turf quality. For the plants without pretreatment ( FIG. 1B ), application of Pigment Blue 15 showed higher turf quality than applications of Signature fungicide, Aliette fungicide, and water. Plants with pretreatment showed higher turf quality than those plants without pretreatment (cf.  FIGS. 1A and 1B ).  
         [0000]     B. Net Photosynthetic Rate (Pn)  
         [0043]      FIG. 2  illustrates the effect of fungicide application on the net photosynthetic rate (Pn) of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd. The arrow indicates the date of first fungicide application.  
         [0044]     High temperature decreased canopy Pn beginning 4 weeks after heat stress ( FIGS. 2A and 2B ). For the plants with fungicide pretreatment, Pn was higher with application of Pigment Blue 15 and Signature fungicide than with application of Aliette fungicide and water ( FIG. 2A ). For the plants without pretreatment, Pn was highest at phthalocyanine application, lowest at water application, and intermediate with application of Signature fungicide and Aliette fungicide ( FIG. 2B ). Pn was higher for plants with pretreatment than for those without pretreatment ( FIGS. 2A and 2B ).  
         [0000]     C. Chlorophyll Content  
         [0045]      FIG. 3  illustrates the effect of fungicide application on the chlorophyll content of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd. The arrow indicates the date of first fungicide application.  
         [0046]     Chlorophyll content in the fresh weight basis increased at high temperature treatment ( FIGS. 3A  and B). For plants with pretreatment, chlorophyll content was highest with application of Signature fungicide and Pigment Blue 15, lowest at water application, and intermediate with application of Aliette fungicide ( FIG. 3A ). For plants without fungicide pretreatment, chlorophyll content was higher with application of Signature fungicide and Pigment Blue 15 than with application of Aliette fungicide ( FIG. 3B ). Chlorophyll content was higher for plants with pretreatment than for those without pretreatment ( FIGS. 3A and 3B ).  
         [0000]     D. Photochemical Efficiency (Fv/Fm Ratio)  
         [0047]      FIG. 4  illustrates the effect of fungicide application on the chlorophyll photochemical efficiency (Fv/Fm) of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd. The arrow indicates the date of first fungicide application.  
         [0048]     Photochemical efficiency (Fv/Fm) declined beginning 1 week after high temperature treatment ( FIGS. 4A and 4B ). For the plants with and without fungicide pretreatment, Fv/Fm was highest at application of Pigment Blue 15, followed by application of Signature fungicide, Aliette fungicide, and water. Fv/Fm was higher for the plants with pretreatment than for those without pretreatment.  
         [0000]     E. Carotenoids Content  
         [0049]      FIG. 5  illustrates the effect of fungicide application on the carotenoids content of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd. The arrow indicates the date of first fungicide application.  
         [0050]     Carotenoids content increased in high temperature treatment ( FIGS. 5A and 5B ). For the plants with or without pretreatment, carotenoids content was higher with application of Signature fungicide and Pigment Blue 15 than with application of Aliette fungicide and water ( FIG. 5A ). Carotenoids content was higher in plants with pretreatment than for those without pretreatment ( FIGS. 5A and 5B ).  
         [0000]     F. Shoot Growth Rate in Canopy Height  
         [0051]      FIG. 6  illustrates the effect of fungicide application on shoot growth rate in height of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd. The arrow indicates the date of first fungicide application.  
         [0052]     Shoot growth rate in canopy height increased in 2 weeks of high temperature treatment and then declined beginning 4 weeks after high temperature treatment in plants with and without pretreatment ( FIGS. 6A and 6B ). Shoot growth rate was higher with application of Signature fungicide and pigment than with application of Aliette fungicide and water for plants with and without pretreatment ( FIGS. 6A and 6B ). Growth rate was higher in plants with fungicide pretreatment than for those without pretreatment ( FIGS. 6A and 6B ).  
         [0000]     G. Final Root and Canopy Biomass  
         [0053]      FIG. 7  illustrates the effect of fungicide application on root and canopy shoot biomass of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd.  
         [0054]     High temperature treatment decreased both roots and canopy biomass ( FIG. 7 ). Application of fungicide relieved the decline of roots and canopy biomass induced by heat stress ( FIG. 7 ). Both roots and canopy biomass were higher with application of Signature fungicide and Pigment Blue 15 than with application of Aliette fungicide and water for plants with and without fungicide pretreatment ( FIGS. 7A and 7B ). Plants with fungicide pretreatment had higher roots and canopy biomass than for those without pretreatment ( FIGS. 7A and 7B ).  
         [0000]     H. Root Mortality  
         [0055]      FIG. 8  illustrates the effect of fungicide application on root mortality of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd.  
         [0056]     Root mortality was increased by high temperature treatment ( FIG. 8 ). Fungicide application reduced the increase of root mortality. Application of Pigment Blue 15 produced lower root mortality than application of Signature fungicide and Aliette fungicide for plants with or without pretreatment ( FIG. 8 ). Root mortality was lower for plants with pretreatment than for those without pretreatment ( FIGS. 8A and 8B ).  
         [0000]     I. Tiller Density  
         [0057]      FIG. 9  illustrates the effect of fungicide application on tiller density of Penncross creeping bentgrass at high temperature treatment. Data are shown as mean±sd.  
         [0058]     High temperature decreased tiller density. Applications of Signature fungicide and Aliette fungicide inhibited the decrease of tiller density induced by heat stress. There was no significant difference among applications of Signature fungicide, Aliette fungicide, and Pigment Blue 15 ( FIG. 9 ).  
       Example 2  
       [0059]     Pigment Blue 15 was suspended in water and applied as a foliar spray to creeping bentgrass (variety Penncross) turf with a pressurized sprayer at a spray volume of 1.37 gallons of water per 1000 sq. ft. Pigment Blue 15 was applied at rates of 6.8, 13.9, and 20.4 grams per 1000 sq. ft. Each treatment was replicated 4 times. An untreated plot was included and was also replicated four times. The average color of the bentgrass was visually evaluated at 6 weeks after treatment.  FIG. 1  displays the results. Color was evaluated on a qualitative scale from 1-9, with 9 being the highest quality and 1 the lowest quality. The color ratings with Pigment Blue 15 treatments were significantly different than the untreated check based on analysis of variance.  FIG. 10  shows the results of the trial.  
       Example 3  
       [0060]     Fosetyl-Al (in the form of Aliette brand fungicide), Fosetyl-Al plus Pigment Blue 15 (in the form of Signature brand Aliette fungicide) and Pigment Blue 15 were suspended in water and applied as a foliar spray to creeping bentgrass (variety Penncross) turf with a pressurized sprayer at a spray volume of 1.37 gallons of water per 1000 sq. ft. Treatments were applied at the following rates per 1000 sq. ft:  
                                                           Aliette   4   oz           Signature   4   oz           Signature   8   oz           Pigment   6.8   g           Pigment   13.6   g                      
 
         [0061]     At 6 weeks after treatment, the color ratings were presented below. The color rating with Aliette and the untreated check were not significantly different. Pigment Blue 15 and Signature treatments were significantly different than the untreated check based on analysis of variance.  FIG. 11  shows the results.  
       Example 4  
       [0062]     The procedure of Example 2 was repeated using iprodione fungicide (in the form of 26 GT brand iprodione fungicide) at 4 oz/1000 sq. ft., iprodione at 4 oz/1000 sq. ft. plus Pigment Blue 15 at 6.8 g/1000 s sq. ft., iprodione at 4 oz/1000 sq. ft. plus Pigment Blue 15 at 13.6 g/1000 s sq. ft., and Pigment Blue 15 at 13.6 g/1000 sq. ft. At 6 weeks after treatment, the color ratings were as follows. Turf treated with iprodione was not significantly different than the untreated check. Turf treated with iprodione plus Pigment Blue 15 at both rates and Pigment Blue 15 alone were significantly greener than the untreated.  FIG. 12  shows the results.