BULLETIN 250

PENNSYLVANIA

FLOWER GROWERS

APRIL, 1972

AReal Winner!: Miss Pennsylvania Flower Queen enhances the awards she presented to Allied Florist participants in the Philadelphia Flower Show. The gold plaques went to retailers Marty Carroll Florists,Albrecht's Flowers, Parkway Flowers, Scott Florists and Andrew Strang Florists for their exhibits. The cupheld by Queen Nancy Liggitt went to Ray Morris, Parkway Flowers, for "originating, chairing and commentating 'Fun With Flowers'," Allied's popular daily demonstrations.

ALLIED FLORISTS OF DELAWARE

VALLEY PROMOTE FLOWERS AT

PHILADELPHIA FLOWER SHOW

PRETTY PRESENTER FOB A PERFECT PERFORMANCE - Nancy Liggitt, Miss Pennsylvania Flower Queen, helps Robert M. Cullers, Executive Director. Allied Florists of Delaware Valley, present Ray Morris a trophy for his unique and popidar performances at Allied'sfour times daily demonstrations at the Philadelphia Flower Show. "Farmer Ray" is wearingone of the costumes he used during his "Fun With Flowers" demonstrations, which attractedover 10,000 viewers during the eight-day show.

Allied Florists of Delaware Valleywas one of the bulwarks at the MarchPhiladelphia Flower and GardenShow, the East Coast's largest flowerevent.

"Art Reflects Nature" was the apropos theme of Allied's large 45' x 10'exhibit. Designed by Harold Cook,Cook's Florists, Runnemede, N. J., theexhibit featured a collection of art byarea artists—with the theme of eachillustration matched in flower arrangements.

For the first time in years, individual retailer exhibits were broughtback into the Show. Each of the fiveAllied retailer exhibits was awardeda bronze medal from the Pennsylvania Horticultural Scoiety, as well asa gold plaque from Allied.

The calibre of the Allied-sponsored,retailer's 8' x 10' exhibits was reflec

ted in the response from the Show's111,000 visitors. Letters and phonecalls were received by the participants: Marty Carroll Florists, Parkway Flowers, Scott Florists and Andrew Strang Flowers, all of Philadelphia, and Albrecht's Flowers, Nar-berth, Pa.

The third element of Allied's participation consisted of a popular fourtimes daily demonstration presentedby Ray Morris, Parkway Flowers. liewas awarded a trophy for his superbperformance. Iiis entertaining demonstrations, "Fun With Flowers," attracted a standing room only audiencefor each of the 28 shows, reachingmore than 10,000 people during theeight-day Flower Show.

On hand to present the Alliedawards was 19-year-old Nancy Liggitt,named Miss Pennsylvania FlowerQueen last fall.

INTERCOLLEGIATE

FLOWER JUDGING

CONTEST-1972

Petek B. Pfahl

The thirty-first annual National Intercollegiate Flower Judging Contestfor 1972 was held at San Luis Obispo,California. It is sponsored jointly bythe Society of American Florists andPi Alpha Xi (National Honorary Floriculture Fraternity).

The Perm State Team placed sixthout of ten teams with WashingtonState University placing first.

Ted Palpant was fifth out of thirtycontestants. The rest of the Perm Stateteam consisted of Joan Bowman, TomMaezko and Ed Falk as alternate.The team was coached by Peter B.Pfahl.

While in California the team visitedSan Francisco, Los Angeles, HearstCastle as well as several orchid, roseand palm growers.

The 1973 contest will he held atNorth Carolina State University.

PENNSYLVANIA

FLOWER GROWERS

BULLETIN 250

APRIL, 1972

OFFICERS

PRESIDENT MARTIN P. GOIIXGohn's Greenhouses

Willow Grove. Pa. 19090

V. PRESIDENT J. ROBEHT OGLEVEEOglevee Floral Co.

Connellsville, Pa.

TREASURER AND EXECUTIVESECRETARY ... HOWARD G. KRUPP

P.O. Box 247. Chalfont, Pa. 18914

EDITOR JOHN W. MASTALERZ907 Glenn Circle SouthSlate College, Pa. 16801

CHEMICAL SOAKS FOR PREVENTION

OF GROWTH OF PATHOGENIC

ORGANISMS ON CLAY AND PLASTIC POTS

Lester P. Nichols and Mildred H. Jodon1

In some greenhouse operations itis necessary to reuse clay or plasticpots. If a crop affected with a fungusor bacterial disease has been growingin these pots, the threat of the nextcrop becoming affected with the samedisease is great. The pathogenic fungior bacteria may grow into the poresof clay pots or may be in soil particlesclinging to plastic pots. When thesepots are refilled with soil and the newcrop is planted, serious disease outbreaks may result. Steaming clay potsis very effective in killing any pathogens in or on clay pots. However,some growers do not have facilitiesfor steaming. In addition, many plasticpots may melt if subjected to a temperature high enough to kill the pathogens. Disinfestant soaks may be usedif steam is not available or if plasticpots are involved.

Formaldehyde is very effective ineliminating pathogens from pots but ithas an offensive odor, the solution isirritating to the hands of workers, andthe fumes may be toxic to workers andare phytotoxic to plants. Walton (1)compared the effectiveness of Cloroxand L-F 10 with formaldehyde againstThielaviopsis basicola, Rhizoctonia so-lani, Fusarium oxysporum f. sp. lyco-persici. Verticillium albo-atrum andPythium sp. He found that Clorox didnot eliminate Fusarium but did eliminate the other fungi at a concentration of 1.05& L-F 10 at a concentration of 0.43% controlled all fungi in a10 minute soak and at a concentrationof 0.22% gave complete control in a 60minute soak. Formaldehyde also givescomplete control.

1 Professor and Research Aide, respectively,Department of Plant Pathology, ThePennsylvania State University, UniversityPark, Pennsylvania 16802.

Clorox has one of the disadvantagesof formaldehyde in that it may irritatethe hands of workers. In addition anew solution must be made up ratheroften as it breaks down and becomesineffective after a short time. L-F 10may be irritating to the hands of theworkers. If run through spray rigs forlarge scale disinfestation of benchesor floors, it may form an insolublegummy residue which fouls the working parts of the sprayer. In addition,

at higher concentrations, it may leavea gummy residue on clay or plasticpots.

Experimental MethodsIn order to find more effective dis

infestant soaks for use on clay andplastic pots, the following test wascarried out. The chemicals listed inTable 1 were compared with the effectiveness of formaldehyde. Pieces ofclay pot about % to % of an inch

(Continued on page 6)

Table 1

DISINFESTANTS USED

MATERIAL CONCENTRATION

1. L-F 10 (potassium ricinolate, o-benzyl-p-chlorophenol) 3 oz/5 gal (1:200)

2. Clorox (5.25% sodium hypochlorite) 10% (1:9)

3 Roccal (10% alkyldimelthyl-benzyldimethylammoniumchloride)

1 oz/2 gal. (1:25000)

4 Proctor & Gamble Experimental Disinfectant PG-141 1 oz/gal

5. Proctor & Gamble Experimental Disinfectant PG-142 1 oz/gal

6. Bromodine (40% alkyl (12) (ethycyclomidinium) 1 oz/gal (1:400)3-hydroxyl, 3-ethyl sodium alcoholate, 2-methylsodium carboxytate-tridecylopolyoxethylene ethanol-iodine complex, 20% triethanolamine sulfonatetridecylpolyoxyethylene ethanol-bromine complex.)

7. Hyamine 2389 (50% methyldodecylbenzyl trimethylammonium chloride and methyl-dodecylxylene bis(trimethylammonium chloride).

8. Consan 20 (9% dimethyl benzylammonium chlorides,9% dimethyl ethylbenzylammonium chlorides, 2%dimethyl benzylammonium chlorides.)

9. Formaldehyde 37%

10. Lysol 16.5% soap, 2.8% O-phenyl-phenol, 2.7% o-benzyl-p-chlorophenol, 1.8% alcohol, 1.5% xylenols, 0.9%isopropyl alcohol, 0.9% tetrasodium ethylenediaminetetra-acetate.

10A. Nolvasan Solution (2% 1, 1i-hexamethlylenebis[5-(p-chlorophenyl) biguanide] diacetate)

11. Check—Distilled Water

1 oz/3 gal

Vi oz/2 gal

1 pt/6 gal

lVi oz/gal

1 oz/gal

Promote Floriculture Research

at Penn State

CONTRIBUTE TO

DILLON RESEARCH FUND

IN 1972

Allburn Florist, Inc., ErieAmerican Horticultural Supply Co., New York, N.Y.Charles A. Bortmas Greenhouses, ButlerBrighton By-Products Co., Inc., New BrightonByer Bros., Inc., ChanibersburgCalifornia-Florida Plant Corp., Stuart, FloridaL. B. Coddington Co., Murray Hill, New JerseyGeorge Didden Greenhouses, Inc., HatfieldDietz Florist, McKees RocksJ. L. Dillon, Inc., BloomsburgDillon Floral Products, Inc., BloomsburgDrayer Florist & Greenhouse, ReynoldsvillePaul Ecke, Inc., Encinitas, CaliforniaEdwards' Flowers, Inc., TamaquaBard Eichelberger, NeffsvilleEmerick's Greenhouse, New BrightonRaymond A. Fleck, Inc., SouthamptonFloral Acres, Inc., Delray Beach, FloridaL. Edward Folk Florist, Inc., BloomsburgE. C. Geiger, HarleysvillcGeorge's Flowers, CarlisleGerman Seeds, Inc., SmethportGraber the Florist, Highland Falls, New YorkGraham Florist, BradfordLouis Hahn & Son, Inc., PittsburghJoseph Harris Co., Inc., Rochester, New YorkPeter Hellberg Company, ChalfontThe John Henry Company, Lansing, MichiganJoseph H. Hill Company, Richmond, IndianaJames A. Himes, Friedl-Elverson Pottery Co., New BrightonF. C. Hinkel & Bro., Inc., PittsburghHoliday Gardens, Inc., RutledgeKasardas' Greenhouses, WyomingHerman Lederer Sons, ParkerfordLinn C. Lengenecker, ManheimJohn H. Marx, MendenhallMcCurio Florist Co., Inc., PittsburghHenry F. Michell Co., King of Prussia

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Miller's Wholesale Florist, AltoonaClinton F. A. Miller, Geo. J. Ball, Inc., CoopersburgNevill's Flowers, MontoursvilleOelschig's Nursery, Inc., Savannah, GeorgiaOglevee Floral Co., ConnellsvilleMartha Orient, PittsburghGeo. W. Park Seed Co., Inc., Greenwood, S.C.Pennsylvania Perlite Corporation, Lehigh ValleyPeterson's Greenhouse, SpringdaleL. K. Philips & Sons, Florists, OxfordJohn J. Pranulis Greenhouses, ButlerDonald S. Pratt, AvondaleS. Russell Prizer, ParkerfordProper's Greenhouses, BradfordNiels Rasmussen, ChristianaReiniger Bros., Inc., HatboroF. O. Rinker & Sons, Inc., BloomsburgRoyer's Flower Shop, LebanonRydal Flower Gardens, RydalSawyer & Johnson, Inc., BethlehemOtto A. Schmidt, Florist, Fox Chase, PhiladelphiaGustav H. Schroeder, Newtown SquareBernard R. Sherman Agency, LancasterClaymore C. Sieck, Baltimore, MarylandGene Smith Florist & Greenhouses, WilliamsportX. S. Smith, Inc., Red Bank, New JerseyStoney Ledge Greenhouse, IrwinSyracuse Pottery, Inc., Syracuse, New YorkJoseph Thomas Florist of Creensburg, JeannetteW. W. Thomson Co., West Hartford, ConnecticutVosters Nurseries & Creenhouses, Inc., SecaneE. B. Walton & Sons, Kennett SquareFrank P. Walton, Kennett SquareWeiland Greenhouses, New CastleChas. M. Wernig's Sons, YorkWinandy Greenhouse Construction, Inc., Richmond, IndianaZelienople Greenhouse Co., Zelienople

1971 ROSE FUNGICIDE TRIALSLester P. Nichols, Paul E. Nelson, and Alvan Donnan1

During the 1971 season, severalfungicides were separately evaluatedin replicated, randomized trials forthe control of black spot (Diplocarponrosae) and powdery mildew (Sphae-rotheca pannosa) of rose. The cultivarScarlet Knight was used for the blackspot trial and the cultivar ChristianDior for the powdery mildew trial.The trials were conducted in cooperation with Longwood Gardens of Kennett Square, Pennsylvania in theLongwood Gardens nursery. The roseplants for the trials were provided bythe Conard-Pyle Company of WestGrove, Pennsylvania.

Each plot consisted of 5 plants andeach treatment was replicated 6 times,so that 30 plants were involved ineach treatment. There were 8 treatments, including the control treatment, for the evaluation of fungicidesfor black spot control and 8 treatments, including the control treatment, for the evaluation of fungicidesfor powdery mildew control.

Fungicides to be evaluated (Table1) were applied as sprays on a weeklyschedule beginning June 22 and ending September 28, 1971. The sprayswere applied with a six nozzle "Cornell" spray gun. The sprayer used wasa portable, gasoline-powered spray rigset to operate at 200 pounds pressure.It was designed so that a 10 gallonplastic container holding the properdilution of each fungicide under testcould be placed on a platform on thesprayer and the fungicide be adequately agitated while the spray wasapplied.

In the powdeiy mildew trial MillerNu-Film 17, a residue extender, wasadded to each treatment at each sprayapplication. In the black spot trial theMiller Nu-Film 17 material was ad

ded to treatments 1, 2, 3, 5, 6 and 7

1 Professor of Plant Pathology Extension,Professor of Plant Pathology and Graduate Student, respectively. The Department of Plant Pathology, The Pennsylvania State University, University Park,Pennsylvania.

Table 1. Materials, Rates of Application for The Pennsylvania State University—LongwoodGardens Rose Spray Trials—1971

Powdery Mildew

Treat No. Material 100 Gals.

1.

2.

3.

4.

5.6.

7.

Acti-dione PM 0.027% WPPhaltan 2.6 FlowablePhaltan 75% WPEL273 7.2% EC

Benlate 50% WPMallincrodt MF-508Cela W524 20% ECCheck

6 ml. of Miller Nu-Film 17 added totreatments 1 through 7.

3 lbs., 2 oz.lib.lib.355 ml.8 oz.

8 oz.

293 ml.

Black Spot

Treat No.

1. Fore 80% WP

2. Phaltan 2.6 Flowable3. Phaltan 75% WP

4. "Phaltan 75% WP5. Benlate 50% WP

6. Daconil 2787 75% WP

7. Cela W 524 20% EC

8. Check—Sprayed with water

V/> lbs.1 lb.1 lb.

8 oz.

8 oz.

6 ml, of Miller Nu-Film 17 added to treatments 1,2, 3, 5, 6, &7"6 ml. of Dupont Spreader-Sticker added to treatment 4.

at each application. Dupont Spreader-Sticker was added to treatment 4 ateach application instead of the Miller-Nu-Film 17 material. The controlplots in the black spot trials weresprayed with water at each spray application. To avoid severe defoliationby black spot in the powdeiy mildewtrial, Fore, a maneb fungicide, wassprayed on the entire powdery mildew trial each time a spray application was made starting June 22. Thisapplication was made after each ofthe powdery mildew materials wereapplied and had dried.

On August 18, September 14 andOctober 7, visual estimates of the percent foliage exhibiting black spotsymptoms and the percent defoliationdue to black spot were made. At thesame time visual estimates of the percent foliage and flower buds showingpowdeiy mildew symptoms weremade for each plant under test. In

— 5 —

the index used, 0 =0 — 0.9% defoliation or infection; 1.0 = 1 — 10% defoliation or infection; 2.0 = 11 —20% defoliation or infection; 2.0 = 21— 30% defoliation or infection; and10.0 = 91 — 100% defoliation or infection. Results of the evaluations forblack spot are given in Table 2 andfor powdery mildew in Table 3.

In the black spot trial, Daconil 2787gave the best control of black spotfollowed by Cela W 524 and Phaltan75% WP with the Nu-Film 17 andwith the Dupont Spreader-Sticker.Fore and the Phaltan 2.6 flowableboth gave good control. Benlate wasonly slightly better than the un-sprayed check.

In the powdeiy mildew trial, EL273 gave the best control followed byBenlate and Cela W 524. None of theother materials gave acceptable control.

(Continued on back page)

CHEMICAL SOAKS FOR POTS-

(Continued from page 1)

square were placed into flasks containing a vermiculite V-8 juice medium and sterilized. The medium wasthen inoculated with one of the following plant pathogens: Pythium sp.,Rhizoctonia solani, Cylindrocladiumscoparium, Verticillium albo-atrum,Thiehviopsis basicola, Fusarium oxy-sporum f. sp. dianihi, and Xanthomo-nas pehrgonii. After 3 weeks the claypieces were rinsed in running tapwater to remove the particles of thegrowth medium. Eight washed piecesfrom each of the inoculated flaskswere then soaked in solutions of thetest materials for 10 minutes and eightpieces were soaked in the test materials for 30 minutes. The test materials and the concentrations usedare listed in Table 1. These concentrations are the normal rates suggested by the manufacturers on the

labels or in the case of Clorox or formaldehyde, concentrations normallyused in plant propagation areas or inthe laboratory lot disinfestant purposes. In this and subsequent tests,pieces soaked in distilled water wereused to check on the growth of thetest organisms. At the end of the soakperiod the pieces were drained andfour pieces from each treatment wereplaced on potato dextrose agar incovered petri dishes and incubated atroom temperature for 12 days. Duringthis time observations were made onthe presence or absence of growth ofthe test organism on the agar surrounding the pieces. Normal growthof all organisms was found on all control plates. If no growth was foundaround any of the four clay piecesafter 12 days then that particular material was rated as being effective in

TABLE 2

Effectiveness of Disinfestant Soaks on Test Organisms Grown on ClayPot Fragments (Test No. 1).

TEST ORGANISM

Material

1. L-F 10

2. Clorox

3. Roccal

4. PG-141

5. PG-142

6. Bromodine

7. Hyamine 2389

8. Consan 20

9. Formaldehyde

10A. Nolvasan Sol

10

30

10

30

10

30

10

30

10

30

10

30

10

30

10

30

10

30

10

30

E — — — — E EE _____ E

E ______

E ______

E ______

E _____ E

E ______

E ______

E E E E — E EE E E E E E E

IE = Effective — no growth of organisms on any clay piece2— = Not effective — growth of organism on one or more clay pieces

— 6 —

controlling the growth of that particular test organism. If growth wasfound around one or more pieces,then the material was rated as beingineffective. The results of this test areshown in Table 2.

ResultsIn this test it was found that the

only disinfestant effective against allseven of the test organisms was formaldehyde. With the exception ofRhizoctonia, it was effective againstall the organisms at both the 10 andthe 30 minute soaks. Clorox was effective against Xanthomonas and Thiehviopsis at both soak times, whilePG-141, PG-142, and Consan 20 wereall effective against Xanthomonas atboth times.

To determine if stronger concentrations of the materials and/or longersoak times would improve the performance of the test chemicals the testwas repeated using the chemicals atthe concentration recommended onthe label(X), twice the recommendedstrength (2X), and four times therecommended strength (4X). Soaktimes were 10, 30, and 60 minutes. Inthis test Lysol was substituted for theNolvasan Sol material. The results ofthis test are shown in Table 3. As inthe first test it was found that theonly disinfestant effective against allseven of the test organisms was formaldehyde.

Using the same test organisms andprocedures, the preceding test wasrepeated using pieces of plastic potabout one half to three quarters of aninch square. All of the disinfestantsexcept PG-141 and PG-142 were used.The results of this test are given inTable 4. As in the clay pot test it wasfound that formaldehyde was the onlymaterial effective against all the testorganisms.

In both the clay pot test and theplastic pot test it was found that insome cases a particular disinfestantwould be effective against an organism at a low concentration or timeand then not be effective at a higherconcentration or time. It is felt thatthis was due in part to the fact thatwhen the pieces were rinsed beforethe dip in the disinfestant, smallpieces of the vermiculite media clungto the pieces. Resistant forms of thefungi such as clamydospores or scle-

Sf^^

TABLE 3

Effectiveness of Disinfestant Soaks on Test Organisms Grown on Clay Pot Fragments (Test No. 2)

ORGANISM — Xanthomonas pelargoniiTIME

10 min. 30 min. 60 min.MATERIAL X* 2X 4X X 2X 4X X 2X 4X

1. L-F 10 ——. — , — E E2. Clorox E E E E E E E E E3. Roccal — E — E E4. PG-141 — E E — E — — E E5. PG-142 E E E E E E E E E6. Bromodine — — — — E E E7. Hyamine 2389 E8. Consan 20 — E E — E E — E E9. Formaldehyde E E E E E E E E E

JO. Lysol — — —— E — E

ORGANISM — • Ftisarium

TIME

10 min. 30 min. 60 min.

MATERIAL X 2X 4X X 2X 4X X 2X 4X

1. L-F 10 E — — E2. Clorox — — — — — — — — —3. Roccal — — — ___ — — _4. PG-1415. PG-142 — __E6. Bromodine — — — — — — — — —7. Hyamine 2389 ___ ___ ___8. Consan 20 — — — — — — — — —

9. Formaldehyde — — E EEE EEE10. Lysol ___ ___ — EE

MATERIAL

ORGANISM — VerticilliumTIME

10 min. 30 min.X 2X 4X X 2X 4X

60 min.

X 2X 4X

ORGANISM — RhizoctoniaTIME

10 min. 30 min. 60 min.MATERIAL X 2X 4X X 2X 4X X 2X 4X

1. L-F 10 — — E — — E E E E2. Clorox ___ _EE EEE3. Roccal — — — — — — — — —4. PG-1415. PG-142

6. Bromodine — — — — — — =— — —7. Hyamine 2389 ___ ___ ___8. Consan 20 — — — — — — — — —

9. Formaldehyde EEE EEE EEE10. Lysol __e — EE EEE

MATERIAL

ORGANISM — PythiumTIME

10 min. 30 min.X 2X 4X X 2X 4X

60 min.X 2X 4X

1. L-F 10 _

2. Clorox EEE EEE EEE3. Roccal — — — — — — — — —4. PG-141 __E — EEE5. PG-142 ___ E — E __E6. Bromodine — — — — — — • — — —7. Hyamine 2389 — — — — — — — _8. Consan 20 — — — — — _

9. Formaldehyde EEE E E E E E E10. Lysol — — — — — — — — E

MATERIAL

ORGANISM — ThiehviopsisTIME

10 min. 30 min.X 2X 4X X 2X 4X

60 min.X 2X 4X

1. L-F 10 E E 1. L-F 102. Clorox 2. Clorox3. Roccal 3> Roccal4. PG-141 4. PG.1415. PG-142 5 pg-1426. Bromodine 6< Bromodine7. Hyamine 2389 7. Hyamine 23898. Consan 20 ___EE g Consan 2Q9. Formaldehyde -EE EEE EEE 9. Formaldehyde

10- Lyso1 — EE 10. Lysol

— E

— E

EEE

EEE— — E

E E —

— E

EEE E E

E E

— E

E E

E

E

E

E

E

E

E

E

E

E

E

ORGANISM — CyUndrocladiumTIME

10 min. 30 min.MATERIAL X 2X 4X X 2X 4X

60 min.

X 2X 4X

1. L-F 10 —2. Clorox ___ __e EEE3. Roccal — — —4. PG-141 —5. PG-1426. Bromodine — — —7. Hyamine 2389 — — —8. Consan 20 — — —9. Formaldehyde E — E EEE EEE

10. Lysol — — — E E

'X = recommended concentration given in table 1.

— 7 —

rotia may have been carried in thesesmall pieces and the disinfestant didnot inhibit their growth.

SummaryIt is apparent that since formalde

hyde is the only effective disinfestantagainst all of the test organisms andsince it does have several disadvantages the grower must decide 1)whether to use it and take precautions against toxic effects to workersand plants or 2) determine the organism or organisms likely to be a prob-

(Continued on page 8)

TABLE 4

Effectiveness of Disinfestant Soaks on Test Organisms Grown onPlastic Pot Fragments

ORGA NISM _ Xanthomontw pelargoniiTIME

ORGANISM — RhizoctoniaTIME

10 min. 30 min. 60 min. 10 min. 30 min. 60 min.MATERIAL Xi 2X 4X X 2X 4X X 2X 4X

E

MATERIAL X 2X 4X X 2X 4X X 2X 4X

1. L-F 10 1. L-F 10 — E E — E E2. Clorox EEE E E E E E E 2. Clorox EEE EEE EEE3. Roccal EEE E E E — E E 3. Roccal — E E E — — E — E4. PG-141 4. PG-1415. PG-142 5. PG-1426. Bromodine EEE E E E E E E 6. Bromodine — E — _ _ E EEE7. Hyamine 2389 EEE E E E E E E 7. Hyamine 2389 — E E EEE EEE8. Consan 20 EEE E E E E E E 8. Consan 20 E — E — E E EEE9. Formaldehyde — E E E E E E E E 9. Formaldehyde E — E EEE EEE

10. Lysol — E E E E E E E E 10. Lysol — E — EEE E — E

ORGANISM — • Fusarium ORGANISM - - PythiumTIME TIME

10 min. 30 min. 60 min. 10 min. 30 min. 60 min.MATERIAL X 2X 4X X 2X 4X X 2X 4X

1.

MATERIAL

L-F 10

X 2X 4X

E

X 2X 4X

_ _ E

X 2X 4X

1. L-F 10

2. Clorox 2. Clorox EEE EEE EEE3. Roccal E 34. PG-141 4. PG-1415. PG-142 5. PG-1426. Bromodine E E E — 6. Bromodine E — E E EEE7. Hyamine 2389 — — —

— E — — — — 7. Hyamine 2389 ^_ _ _ E — E8. Consan 20 E — E E E E E 8. Consan 20 E _ __ _ — — E9. Formaldehyde — E — E E E E E E 9. Formaldehyde EEE EEE EEE

10. Lysol E 10. Lysol

MATERIAL

ORGANISM — VerticilliumTIME

10 min. 30 min.X 2X 4X X 2X 4X

60 min.

X 2X 4X

1. L-F 102. Clorox — — — ___ __e3. Roccal — — — — — — — EE4. PG-141

5. PG-142

6. Bromodine — — — — — — EE —7. Hyamine 2389 ___ ___ ___8. Consan 20 ___ __E EEE9. Formaldehyde EEE EEE EEE

10. Lysol — — E — E — — E E

ORGANISM — CylindrochdiumTIME

10 min. 30 min.

MATERIAL X 2X 4X X 2X 4X60 min.

X 2X 4X

1. L-F 102. Clorox _E— __E — EE3. Roccal — — — — — — — — —4. PG-141

5. PG-1426. Bromodine — — — — — — — — —7. Hyamine 2389 ___ ___ ___8. Consan 20 — — — — — — — — —9. Formaldehyde _E— — EE — EE

10. Lysol — — — — — — — — —

IX = recommended concentration given in table 1.

MATERIAL

ORGANISM — ThiehviopsisTIME

10 min. 30 min.

X 2X 4X X 2X 4X60 min.

X 2X 4X

1. L-F 10

2. Clorox EEE E E E E E E

3. Roccal — — — — E — — E E

4. PG-141

5. PG-142

6. Bromodine E E E E E E E

7. Hyamine 2389 E

8. Corsan 20 E — E — E E — E E

9. Formaldehyde EEE E E E E E E

10. Lysol — — —— —

E—

E —

(Continued from page 7)

lem on the particular crop beinggrown and then select one of theother disinfestants shown to be effective against these organisms.

Literature Cited1. Walton, G. S. 1965. Chemical dips

for control of fungi on clay pots. (Abst.)Phytopathology 55:1081.

SEE THE LATEST ON PLANT DISEASES

FOR SUGGESTIONS ON TREATING POTSPage 12

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